guo hou loo, farhana raduan, zunaidah abu samah and nik ritza kosai .  (2026).  prevalence and longitudinal development of sarcopenic obesity in an asian obese population: a large bioelectrical impedance analysis study.  - frontiers in nutrition.  1 - 8. 

su teng lau, guo hou loo, shue hong kong, norlaila mustafa, nik ritza kosai.  (2026).  metabolic bariatric surgery versus medical therapy for type 2 diabetes: a 5-year real-world cost and remission analysis.  - obesity surgery.  3777 - 3784. 

wei lun tan, guo hou loo, guhan muthkumaran, nik ritza kosai.  (2026).  long-term weight loss and metabolic outcomes after bariatric surgery in a large asian cohort: a real-world cohort study.  - obesity surgery.  3736 - 3744. 

mohd afiq zulkifli, loo guo hou, nik ritza kosai nik mahmood.  (2026).  tore offers a second chance forbariatric patients.  - lifestyle-bernama.  . 

guo hou loo, meng xian chan, zhun shen tan and nik ritza kosai.  (2026).  giant paraumbilical hernia causing gastric outlet obstruction in a young man with class iii obesity: a case report and literature review.  - frontiers in surgery.  1 - 11. 

loo guo hou, nik ritza kosai nik mahmood, farhana raduan, zunaidah abu samah.  (2026).  kajian pakar dan penyelidik ukm dedahkan bahaya obesiti sarkopenik.  - malaysia gazzette.  . 

jo ann andoy galvan, guo hou loo, nik ritza kosai, chai hong yeong, karuthan chinna, rusli nordin, kenneth kwing-chin lee, norlaila mustafa.  (2026).  long-term clinical outcomes and cost-effectiveness of bariatric surgery for type 2 diabetes in malaysia: a 10-year retrospective cohort study.  - journal of multidisciplinary healthcare.  1 - 12. 

guo hou loo, nik aisyah kosai, val michael villareal, guhan muthukumaran and nik ritza nik mahmood .  (2026).  case report: three contrasting presentations of acute oesophageal necrosis and the determinants of outcome.  - frontiers in medicine.  1 - 11. 

wei lun tan, guo hou loo, guhan muthkumaran, nik ritza kosai.  (2026).  long-term weight loss and metabolic outcomes after bariatric surgery in a large asian cohort: a real-world cohort study.  - international congress of medicine and health 2026.  . 

amir abd hamid, loo guo hou, nik ritza kosai, farhana raduan, zunaidah abd samah.  (2026).  obesiti sarkopenik jejas kualiti hidup dalam 'senyap'.  - harian metro.  . 

natasia nicole deser, hans alexander mahendran, guo hou loo and nik ritza kosai.  (2026).  prehabilitative parenteral nutrition and surgery-related muscle loss in patients undergoing major upper gastrointestinal surgery: a single-centre observational cohort study.  - frontiers in nutrition.  1 - 10. 

dr. mariyam nahuza, dr loo gou hoo, associate professor dato dr nik ritza kosai.  (2026).  transoral outlet reduction (tore) for late complications of roux-en-y gastric bypass a case series of weight recidivism & dumping syndrome.  - sabah surgical conference 2026 with mugis.  . 

wei lun tan, guo hou loo, guhan muthkumaran, nik ritza kosai .  (2026).  long term weight loss and metabolic outcomes after bariatric surgery in a large asian cohort: a real-world cohort study .  - sabah surgical conference 2026 with mugis .  . 

su teng lau, guo hou loo, nik ritza kosai .  (2026).  metabolic bariatric surgery versus medical therapy for type 2 diabetes: a 5-year real-world cost and remission analysis .  - sabah surgical conference 2026 with mugis (ssc26-mugis).  . 

mohd saufee al firdaus mohd ismail, guo hou loo, guhan muthkumanan, nik ritza kosai.  (2026).  topical emla cream as adjunct analgesia in postoperative pain control for open inguinal hernioplasty under local anesthesia: a pilot double-blind randomized controlled trial.  - world journal of surgery.  369 - 375. 

nik ritza kosai nik mahmood.  (2025).  belon telan allurion jadi pilihan.  - harian metro.  . 

rafe'aton md. ali, nik ritza kosai nik mahmood, loo guo hou.  (2025).  allurion ballon: a medical innovation to treat obesity without surgery.  - fokus bernama.  . 

nik ritza kosai nik mahmood.  (2025).  kaedah belon bantu atasi masalah obesiti.  - berita harian.  . 

richelle huey bing chua, guo hou loo, nani hl, guhan muthkumaran, nik ritza kosai.  (2025).  bariatric surgery as an adjunctive treatment for failed back surgery syndrome: a case report highlighting a multidisciplinary approach.  - cureus.  1 - 6. 

solomon raj vasudayan, guo hou loo, guhan muthkumaran, nik ritza kosai .  (2025).  gastric perforation secondary to a hyperinflated intragastric balloon: a case report and management approach.  - cureus.  1 - 7. 

nik ritza kosai nik mahmood, kok wei hao, lee chong chearn, azmi baharudin, deborah chew chia hsin, nor azmin aziz, norlela sukor.  (2025).  hctm pioneers endoscopic sleeve gastroplasty in fight against obesity.  - malaysiakini.  . 

nik ritza kosai nik mahmood.  (2025).  bariatrik bukan jalan pintas untuk cantik.  - sinar harian.  . 

halina md. noor, nik ritza kosai nik mahmood.  (2025).  rawatan obesiti tanpa pembedahan, parut.  - utusan malaysia.  . 

fauziyah ashraf, guo hou loo, khairul anwar abdul rahman, wan izzah wan jaffar, guhan muthkumaran, nik ritza kosai.  (2025).  sister mary joseph’s nodule revealing occult breast cancer: a rare metastatic manifestation.  - surgery case reports.  1 - 5. 

theeran kaur gill, guo hou loo, guhan muthkumaran, nik ritza kosai.  (2025).  posterior membranous tracheal injury during mckeown oesophagectomy. a case report with literature review..  - frontiers in oncology.  1 - 6. 

mardiana mardan, wei keat ooi, arif hameed sultan, guo hou loo, nik ritza kosai.  (2025).  delayed strangulated hiatal hernia post-gastrectomy masquerading as diaphragmatic hernia: a diagnostic pitfall.  - cureus .  1 - 9. 

solomon raj vasudayan, guo hou loo, mogaraj sellapan, geok chin tan, nik ritza kosai.  (2025).  small bowel volvulus secondary to meckel’s diverticulum with meso-diverticular band: a case report and literature review.  - cureus.  1 - 5. 

soon li wei, nik ritza kosai nik mahmood, norlela sukor.  (2025).  esg: a breakthrough option for weight loss, say hctm experts.  - bfokus.  . 

muhamad zulhilmi akmal zainuddin, jemaima che hamzah, nik ritza kosai nik mahmood, cheng teck chee, mae-lynn catherine bastion.  (2025).  nutritional optic neuropathy: bariatric surgery gone wrong.  - cureus.  1 - 12. 

wan izzah wan jaffar, guo hou loo, fazarina mohammed, deborah chia hsin chew, guhan muthkumaran and nik ritza kosai.  (2025).  case report: rare case of signet ring gastric adenocarcinoma with rectal metastasis.  - frontiers in oncology.  1 - 6. 

firdaus che ani, guo hou loo, richelle huey bing chua, kok-yong chin, nik ritza kosai.  (2025).  integrating cruroplasty with laparoscopic sleeve gastrectomy: a strategy to mitigate gerd symptoms in obese patients. a randomized control trial.  - langenbeck's archives of surgery.  1 - 7. 

wan ahmad atarmizi, nik ritza kosai nik mahmood.  (2025).  why bariatric surgery is classified as a treatment for disease, not an easy way out.  - sinar daily.  . 

nik ritza kosai, jeffrey bronks, loo guo hou.  (2025).  scalable solutions for mid-tier obesity: revisiting the role of igbs.  - omnihealth practice.  . 

mang ning ong, guo hou loo, guhan muthkumaran, suria hayati md pauzi, nik ritza kosai.  (2024).  incarcerated incisional hernia: an unusual presentation of metastatic endometrial carcinoma.  - cureus.  1 - 9. 

amrit manik nasta, ramen goel, rishi singhal, luc lemmens, sarfaraz baig, yosuke seki, arun prasad, sonja chiappetta, mohammad kermansaravi, marc vertruyen, beniamino pascotto, juan santiago azagra, waleed al-khyatt, gennaro martines, diva y villao, leandro revello, marco rioseco, francesco martini, arnaud liagre, gildas juglard, giovanni dapri, monika a proczko-stepaniak, adel k abou-mrad, hosam m elghadban, christine stier, jasper l van herck, safwan abdulrahman taha, ozan sen, bruno dillemans, stijn van hoef, mathieu vandeputte, sofie viskens, paolo gentileschi, raj palaniappan, nasser sakran, thomas h shin, ali aminian, matteo uccelli, stefano olmi, giovanni c cesana, marco anselmino, nicolas p a debergh, daniel gärtner, wah yang, digvijay s bedi, kamal mahawar, haidar abdalah, hytham hamid, rajesh gianchandani-moorjani, vincenzo bottino, alfonso bosco, errichetta napolitano, ravikrishna mamidanna, brij madhok, débora acín-gándara, manuel medina-garcía, sajith kumar, rajneesh bankenahally, yasmin sarfaraz, heather fry, tom wiggins, krishnamohan yarlagadda, anna popp, tadeja pintar, francesk mulita, georgios-ioannis verras, michail vailas, george skroubis, manish khaitan, giovanni lezoche, urs pfefferkorn, shahab shahabi, amir davarpanah, cunchuan wang, zhiyong dong, amador garcia ruiz de gordejuela, ramón vilallonga, Óscar gonzález, piotr major, piotr zarzycki, justyna rymarowicz, yannick nijs, jaydeep palep, randeep wadhawan, deepa kizhakke veetil, carlos esquivel, manuel garcía, fernando martinez lascano, maría muriel, josé foscarini, fajer nassour, kazunori kasama, agustin duro, sang hyun kim, aatif inam, sharad sharma, radwan kassir, manuel aceves avalos, saeed alsareii, miljana vladimirov, michela campanelli, domenico benavoli, emanuela bianciardi, juan carlos sebastián-tomás, ramón trullenque-juan, josé Ángel díez-ares, octávio viveiros, rui ribeiro, muzaffer al, ahmet gökhan, nikhilesh krishna, bassel haj, ramy gfely, jabra arraf, abdallah omari, ali awad, pranoy gupt, jacques himpens, jonathan super, vasileios charalampakis, markos daskalakis, mohamed sahloul, spyridon kapoulas, arab rawashdeh, kareem sillah, govindan raghuraman, ana garcia navarro, nr kosai, mohd firdaus che ani.  (2024).  30-day morbidity and mortality of revisional bariatric surgery – an international multi-centre collaborative (broad) study.  - obesity research & clinical practice.  195 - 200. 

farah marzuki, loo guo hou, nik farhan nik fuad, nik ritza kosai.  (2024).  haemorrhagic shock after iatrogenic deep circumflex iliac artery injury during paracentesis: a rare lethal complication.  - cureus.  1-5. 

loo guo hou, guhan muthkumaran, nik ritza kosai.  (2024).  unusual presentation of incarcerated true parahiatal hernia: management of a rare clinical entity.  - cureus.  1-6. 

wei soon pang, guo hou loo, guo jeng tan, mardiana mardan, reynu rajan, & nik ritza kosai.  (2024).  comparative evaluation of early diabetic outcomes in southeast asian patients with type 2 diabetes mellitus undergoing roux-en-y gastric bypass (rygb) verssus sleeve gastrectomy (lsg).  - scientific reports.  1-7. 

jun sen chuah, jih huei tan, mohamad adam bujang, koon khee chan, nik ritza kosai.  (2024).  transcutaneous electric nerve stimulation of acupuncture points improves tolerance in adults undergoing diagnostic upper gastrointestinal endoscopy - a single center, double-blinded, randomized controlled trial.  - surgical endoscopy.  3279 - 3287. 

rajdave s. sadu singh, guo h. loo, guhan muthkumaran, sekkapan t. sambanthan, nik ritza kosai.  (2024).  proximal margin involvement following total gastrectomy for seiwert iii adenocarcinoma: a management dilemma.  - cureus journal of medical science.  1 - 7. 

nik ritza kosai, aishath azna ali, ryan ghita, guhan muthkumaran, ismail ali, guo hou loo, firdaus hayati.  (2024).  one-year outcomes in a supervised program of swallowable intragastric balloon—analysis of 486 patients in a high-volume bariatric centre in malaysia.  - obesity surgery.  3366 - 3371. 

nik ritza kosai nik mahmood.  (2024).  allurion announces publication of new data demonstrating continued weight loss at one year on the allurion program .  - bussiness wire.  . 

rajdave s, gh loo, m. guhan, kosai nr.  (2024).  proximal margin involvement following total gastrectomy for seiwert iii adenocarcinoma; a management dilemma.  - 10th asia-pacific gastroesophageal cancer congress.  . 

fauziyah ashraf, loo guo hou, khairul anwar abdul rahman, wan izzah wan jaffar, guhan muthkumaran, nik ritza kosai.  (2024).  sister mary joseph’s nodule as a metastatic presentation in breast carcinoma.  - international surgical week 2024.  . 

tarmizi z, gh loo, guhan m, azna a, nr kosai.  (2024).  unveiling the mystery of the black oesophagus.  - international surgical week 2024.  . 

nur fatin najlaa mohd nasir; norlia abdullah; nik ritza nik kosai; fuad ismail.  (2024).  atropine for pseudoptyalism secondary to para-oesophageal lymph node metastases from a breast carcinoma: a case report.  - international surgical week.  . 

nik ritza kosai; sou jing kim; firdaus che ani; guhan muthukumanan.  (2024).  ‘performing the unthinkable’ endoscopic retrieval of a retained nasogastric tube using an olympus loop cutter following a thoracoscopic ivor lewis esophagectomy. a case report and review of the literature..  - international surgical week.  . 

nik ritza kosai; guhan muthukumanan; ismail ahmed ali.  (2024).  palliative options in advanced oesophageal cancer: a case report and review of the literature.  - international surgical week.  . 

khairul anwar bin abdul rahman; sarah liyana binti mohd hisham; loo guo hou; wan izzah wan jaafar; fauziyah ashraf; azna ali; guhan muthukumaran; nik ritza kosai.  (2024).  revision laparoscopic mini- gastric bypass and removal of gastric band.  - international surgical week.  . 

nur fatin najlaa mohd nasir; guhan muthkumaran; ismail ahmed ali; nik ritza kosai; aishath azna ali; rozilah ishak; suria hayati md pauzi.  (2024).  xanthogranulomatous inflammation (xgi) of the terminal ileum, caecum, and appendix mimicked as appendicular mass: a case report and literature review.  - international surgical week.  . 

asif sukri, alfizah hanafiah, nik ritza kossai, mohamad aznan shuhaili, mustafa mohammed taher, raja affendi raja ali.  (2024).  perbandingan pengekspresan antigen kluster pembezaan dalam subjenis tumor dan darah periferi pesakit kanser gaster .  - sains malaysiana.  3253 - 3262. 

rajdave singh sadu singh, guo hou loo, guhan muthkumaran, aishath azna ali, nik ritza kosai.  (2024).  reversal of roux-en-y gastric bypass to normal anatomy in a severely malnourished patient after metabolic bariatric surgery.  - cureus.  1 - 5. 

loo guo hoo, nadia nafsha baharudin, mohamed arif hameed sultan, reynu rajan, nik ritza kosai, lizawati rasul hamidi.  (2023).  adult idiopathic hypertrophic pyloric stenosis presenting with gastroduodenal intussusception: a rare case report.  - turkish journal of surgery.  377-382. 

alfizah hanafiah, asif sukri, nik ritza kosai, mohamad aznan shuhaili, mustafa mohammed taher & raja affendi raja ali.  (2023).  immunophenotyping of gastritis, gastric ulcer and gastric cancer using a cluster of differentiation (cd) antibody microarray.  - sains malaysiana.  187-197. 

mohamed arif hameed sultan, muhamad hud muhamad zin, firdaus hayati, zulkifli md zainuddin, nik ritza kosai, reynu rajan, zainal adwin zainal abidin, dayang corieza febriany.  (2023).  improvement in erectile dysfunction among male obese patient, following bariatric surgery in hospital canselor tuanku muhriz (hukm).  - obesity surgery.  1506-1518. 

mohamed arif hameed sultan, nik ritza kosai, reynu rajan, mustafa taher, aznan shuhaili, dayang corieza febriany.  (2023).  malignant melanoma of oesophagus: a rare entity.  - gazi medical journal.  82-85. 

nik ritza kosai nik mahmood.  (2023).  how a balloon can help obese persons lose weight.  - the star.  1-7. 

nik ritza kosai nik mahmood.  (2023).  kitakurang-obesity management programme that helps malaysians live healthier, happier and fuller lives.  - kl happening events.  1-3. 

david eng yeow gan, nik ritza kosai nik mahmood, jitt aun chuah, firdaus hayati.  (2023).  performance and diagnostic accuracy of scoring systems in adult patients with suspected appendicitis.  - lagenbeck's archives of surgery.  1-9. 

norlaila mustafa, aznida firzah abdul aziz, nik ritza kosai nik mahmood,norasyikin a wahab,zahara abdul manaf, arimi fitri mat ludin, joyce hong soo synn, mohd helmy mokhtar.  (2023).  cpg management of obesity (2nd edition).  - .  1-122. 

global surgery, globalsurg collaborative, mustafa mohammed taher, nik ritza kosai, dayang nita abdul aziz, reynu rajan.  (2023).  use of telemedicine for postdischarge assessment of the surgical wound: international cohort study, and systematic review with meta-analysis.  - annals of surgery.  1331-1347. 

nik ritza kosai nik mahmood.  (2023).  the business station (bfm).  - what do intragastric balloons offer in obesity management?.  . 

nik ritza kosai.  (2023).  alternatif turunkan berat badan: kaedah bariatrik, belon intragastrik bantu kawal obesiti.  - berita harian.  25. 

nur izreena ismail, khairul najmi muhammad nawawi, deborah chew chia hsin, kok wei hao, nik ritza kosai nik mahmood, gary lee chong chearn, zhiqin wong, azmi mohd tamil, hazel joseph, raja affendi raja ali.  (2023).  probiotic containing lactobacillus reuteri dsm 17648 as an adjunct treatment for helicobacter pylori infection: a randomized, double- blind, placebo- controlled trial.  - helicobacter.  1-11. 

lee qz, nik ritza k, mohd firdaus ca, muhammad m.  (2023).  the impact of laparoscopic intraperitoneal instillation of ropivacaine in enhancing respiratory recovery and reducing acute postoperative pain in laparoscopic sleeve gastrectomy: a double-blinded randomised control; relieve trial.  - obesity surgery.  3141-3146. 

nik ritza kosai nik mahmooh.  (2023).  pembedahan bariatrik rawat obes sahaja.  - metro ahad.  3. 

mohd haidir roslan, mohd asyiq raffali, shawal faizal mohamad, nik ritza kosai nik mahmood, hamat hamdi che hassan.  (2023).  cardiac and metabolic effects of bariatric surgery among obese patients in a malaysian tertiary hospital: a 6-month prospective cohort study.  - journal of the asean federation of endocrine societies.  1-7. 

mza zainuddin, j che hamzah, nr kosai, tc cheng, bastion mlc.  (2023).  nutritional optic neuropathy - bariatric surgery gone wrong.  - 12th conjoint ophthalmology scientific conference.  1-2. 

asif sukri, alfizah hanafiah, nik ritza kosai.  (2023).  cd54, cd55 and cd71 regulate interleukin-8 secretion of helicobacter pylori-infected gastric epithelial cells in strain-dependent manner.  - simposium biologi kebangsaan 2023.  1. 

hajar rubihah dzaraly, syarifah noor nazihah sayed masri, khairulamir zainuddin, nik ritza kosai nik mahmood, maryam budiman, azarinah izaham.  (2023).  the effect of moderate versus deep neuromuscular blockade on the surgical rating scale in laparoscopic sleeve gastrectomy in a malaysian tertiary university hospital: a randomised clinical trial.  - malaysian journal of anaesthesiology.  118-133. 

m. hairulhazuan h, st sambanthan, nr kosai.  (2023).  extensive small bowel ulcers with overt haemorrhage secondary to nsaid usage, a case report.  - british journal of surgical science.  104 - 107. 

wah-kheong chan, soek-siam tan, siew-pheng chan, yeong-yeh lee, hoi-poh tee, sanjiv m., khean-lee goh, anis safura ramli, feisul m., nik ritza k. dan raja affendi ra.  (2022).  malaysian society of gastroenterology and hepatology consensus statement on metabolic dysfunction-associated fatty liver disease.  - gastroenterology and hepatology.  795-811. 

nik ritza kosai, raja affendi raja ali.  (2022).  global multi-stakeholder endorsement of the mafld definition.  - the lancet gastroenterology and hepatology.  388-390. 

mohanraj t, nik ritza kosai.  (2022).  predictors associated with morbidity of ureteral stent related symptoms (srs) in patients with in-dwelling ureteric stents in hospital serdang.  - assessment of dissertation defense day.  21. 

david gan, nik ritza kosai.  (2022).  performance and diagnostic accuracy of scoring systems in patients with suspected adult appendicitis.  - assessment of dissertation defense day.  25. 

masayuki o, soo min a, yosuke s, wah y, simon kin hw, suthep u, jefrey m. h, manish k, nik ritza k, weu w, june l, reno r, thejana w, edward o.  (2022).  ten years of change in bariatric/metabolic surgery in the asia-pacific region with covid-19 pandemic: ifso-apc national reports 2021.  - obesity surgery.  2994-3004. 

asif sukri, alfizah hanafiah, nik ritza kosai, mustafa mohammed taher, ramelah mohamed.  (2022).  new insight on the role of helicobacter pylori caga in the expression of cell surface antigens with important biological functions in gastric carcinogenesis.  - helicobacter.  1-8. 

raymond zml, hans am, malaysian upper gastrointestinal surgical society (mugis), ng cb, low ky, sekkapan t, ngo cw, nik ritza kosai, reynu r, mohamad as, ahmad sudiman ms, ramesh g, azrina ab, mahadevan dt, vijaya sa, wan najmi wd, lim sy, kelvin v, moha.  (2022).  esophageal squamous cell carcinoma and adenocarcinoma in malaysia - pooled data from upper gastrointestinal centers in a multiethnic asian population.  - cancer epidemiology.  1-8. 

nik ritza kosai nik mahmood.  (2022).  'sentuhan emas' dr nik ritza kosai.  - harian metro.  1-7. 

asif sukri, alfizah hanafiah, and nik ritza kosai.  (2022).  the roles of immune cells in gastric cancer: anti-cancer or pro-cancer?.  - cancers.  1-14. 

nabilah hisham, alfizah hanafiah, tan geok chin, nik ritza kosai, muaatamarulain mustangin.  (2022).  detection of expressed pro-inflammatory cytokine interleukin-32 in gastric cancer patients from ukm medical centre (ukmmc) using immunohistochemistry (ihc).  - gut 2022.  1. 

nur izreena ismail, raja affendi raja ali, zhiqin wong, khairul najmi muhammad nawawi, wei hao kok, nik ritza kosai nik mahmood, chia hsin chew, chong chearn lee, azmi mohd tamil, hazel joseph.  (2022).  the effect of lactobacillus reuteri probiotic as an adjunct treatment for helicobacter pylori infection in adults.  - gut.  1. 

syarifah nafisah al-yahya, muhammad haffiz haslam mohamed akram, kasturi vijaya kumar, siti nor asyrah mat amin, noor alifah abdul malik, nor ain mohd zawawi, nik ritza kosai nik mahmood,norlaila mustafa, mawaddah azman, and marina mat baki.  (2022).  maximum phonation time normative values among malaysians and its relation to body mass index.  - journal of voice.  457-463. 

nik ritza kosai nik mahmood , muhammad maaya , lee qi zheng.  (2022).  the role of lntraperitoneal instillation of local anaesthesia (ropivacaine) for postoperative pain management in laparoscopic sleeve gastrectomy surgery (lsgs):rosle randomised controlled trial.  - assessment of dissertation defense day.  30. 

nik ritza kosai nik mahmood, hardip singh gendeh, mardiana mardan.  (2021).  managing diabetes through surgery.  - the health.  14-15. 

nik ritza kosai nik mahmood.  (2021).  what to know about obesity in malaysia.  - tatler malaysia.  1. 

abdul gafoor am, reynu r, kirubakaran m, vimal kv, nik ritza kosai nm, tikfu g, haron a.  (2021).  patient and procedure selection for bariatric and metabolic surgery in malaysia- the malaysian consensus.  - medical journal of malaysia.  229-232. 

asif sukri, alfizah hanafiah, nik ritza kosai, mustafa mohamed taher, isa mohamed rose.  (2021).  cluster of differentiation (cd) antigens as biomarkers for prognosis of different subtypes of gastric cancer: a preliminary study.  - precision health in industrial revolution 4.0 (ir 4.0): the technologies and health transformation.  20. 

anivat ai pun, loo guo hou, reynu rajan, nik ritza kosai, norlela sukor.  (2021).  laparoscopic sleeve gastrectomy vs roux-en-y gastric bypass in the remission of type 2 diabetes mellitus: early results from a bariatric centre in malaysia.  - journal of medical and surgical research.  886-894. 

zahra rashidbenam, mohd hafidzul jasman, guan hee tan, eng hong goh, xeng inn fam, christopher chee kong ho, zulkifli md zainuddin, reynu rajan, rizal abdul rani, fatimah mohd nor, mohamad aznan shuhaili, nik ritza kosai, farrah hani imran, min hwei ng.  (2021).  fabrication of adipose-derived stem cell-based self-assembled scaffold under hypoxia and mechanical stimulation for urethral tissue engineering.  - international journal of molecular sciences.  1-32. 

kavitha subramanian, low wy, lau pc, chin kf, chinna k, nik ritza kosai, mustafa taher, reynu r.  (2021).  changes in eating behaviours following bariatric surgery: a prospective study.  - journal of experimental biology and agricultural sciences.  101-109. 

ahmad adib bin mohd nasir, andrea yu-lin ban, syed zulkifli syed zakaria, nik ritza kosai nik mahmood and mohamed faisal abdul hamid.  (2021).  a single tertiary centre outlook on the short-term outcome of bariatric surgery in improving pulmonary parameters and sleep apnoea.  - proceedings of singapore healthcare.  91-98. 

mawaddah azman, ng sze yin, abdullah sani mohamed, marina mat baki, mustafa mohammed taher, nik ritza kosai.  (2021).  surgical versus conventional weight loss therapy for obstructive sleep apnea, a randomized controlled trial: quantitative and qualitative outcome.  - medical journal of malaysia.  23. 

dalilah diyana alfian sulai, theevashini k, nik ritza kosai nik mahmood.  (2021).  diagnostic challenge in silent metastatic invasive breast carcinoma: dysphagia as the only symptom.  - bmj case report.  1-3. 

muhamad hud muhamad zin, theevashini krishnasamy, nik ritza kosai.  (2021).  retro umbilical abscess mimicking infected urachal cyst: a rare presentation from migratory fish bone ingestion.  - gazi medical journal.  466-468. 

alfizah hanafiah, nabilah hisham, tan geok chin, muaatamarulain mustangin, nik ritza kosai nik mahmood.  (2021).  expression of interleukin-32 in gastric cancer patients in ukm medical centre (ukmmc).  - .  1-5. 

reynu rajan, mohammed sam-aan, nik ritza kosai, mohamad aznan shuhaili, tee sze chee, ajay venkateswaran, kamal mahawar.  (2020).  early outcome of bariatric surgery for the treatment of type 2 diabetes mellitus in super-obese malaysian population.  - journal of minimal access surgery.  47-53. 

asif sukri, alfizah hanafiah, noraziah mohamad zin, nik ritza kosai.  (2020).  epidemiology and role of helicobacter pylori virulence factors in gastric cancer carcinogenesis.  - apmis.  150-161. 

jimmy bys, jiafu j, sang uk, masanori t, guoxin li, hh kim, simon l, asim s, kyo ys, woo jh, nik ritza kosai, koji k, kazunari m, hiroshi y, takahiro k, peng cl, young wk, jaideeraj r, bee ct, hk yang, expel study group.  (2020).  extensive peritoneal lavage after curative gastrectomy for gastric cancer study (expel): an international multicenter randomized controlled trial.  - journal of clinical oncology.  279. 

loo guo hou, reynu rajan, azmi mohd tamil, nik ritza kosai.  (2020).  prevalence of obstructive sleep apnea in asian bariatric population: an underdiagnosed dilemma.  - surgery for obesity and related disease.  778-783. 

pei pei lee,theevashini krishnasamy, mustafa taher, nik ritza kosai nik mahmood.  (2020).  partially eroded gastric band after 13 years - endoscopic removal with emergency lithotripter device.  - surgical chronicles.  44-46. 

loo guo hoo, reynu rajan, mahadevan deva tata, nik ritza kosai.  (2020).  changes in the disease-specific quality of life following dor fundoplication. a multicentre cross-sectional study.  - annals of medicine and surgery.  252-255. 

sivesh kk., sheraz rm., pritam s., ewan ag., on behalf of oeasophagogastric anastomosis audit group.  (2020).  the influence of the sars-cov-2 pandemic on esophagogastric cancer services: an international survey of esophagogastric surgeons.  - diseases of the esophagus.  1-12. 

chua shiau ying, loo guo hou, azarinah izaham, reynu rajan, zuraidah che man, esa kamaruzaman, nik ritza kosai.  (2020).  non-invasive versus invasive blood pressure monitoring in patients during laparoscopic bariatric surgery: a prospective method-comparison study.  - journal of medical and surgical research.  778-791. 

nik ritza kosai nik mahmood, hardip singh gendeh, mardiana mardan.  (2020).  the health.  - obesity a serious risk factor in covid-19.  16-17. 

surita binti said, guo hou loo, nik ritza kosai, reynu rajan, rozita mohd, asrul abdul wahab, shamsul azhar shah.  (2020).  reduction in urinary chemokine (c-c motif) ligand 2 (ccl-2) after surgery-induced weight loss.  - scientific reports.  1-6. 

mohd hafidzul bin jasman;zulkifli bin md. zainuddin;goh eng hong;ng min hwei;fam xeng inn;tan guan hee;reynu a/p rajan;nik ritza kosai bin nik mahmood;mohamad aznan bin shuhaili;fatimah binti mohd nor.  (2020).  exploring the role of modified adipose derived stem cell-based self-assembled scaffold in the engineering of full thickness human urethra.  - .  . 

globalsurg collaborative; dayang nita abdul aziz, reynu rajan, mohammed taher, nik ritza kosai.  (2019).  pooled analysis of who surgical safety checklist use and mortality after emergency laparotomy.  - british journal of surgery.  103-112. 

sivaneswaran lechmiannandan, mayurran panirselvam, prema muninathan, narwani hussin, reynu rajan, hatta sidi, nik ritza kosai & c. rajkumar vinayak.  (2019).  resolution of female sexual dysfunction (fsd) among the obese multiethnic malaysian women now a reality with bariatric surgery: a prospective pilot study in malaysia.  - obesity surgery.  1571-1575. 

alfizah binti hanafiah;nik ritza kosai bin nik mahmood;raja affendi bin raja ali;mustafa mohammed taher;isa b mohamed rose.  (2019).  analysis of cluster of differentiation (cd) antigens in h. pylori-associated gastric cancer and non-gastric cancer.  - .  1-6. 

asif sukri, alfizah hanafiah, nik ritza kosai, mustafa mohamed taher, isa mohamed rose & ramelah mohamed.  (2019).  optimization of cryopreserved single cell suspension of gastric epithelial cells for successful dotscantm antibody microarray.  - sains malaysiana.  1105-1110. 

lai jun hai, loo guo hou, mohamad aznan shuhaili, nik ritza kosai.  (2019).  a novel alternative to suture passer for closure of fascial defect in laparoscopic ventral hernia repair: a case report.  - international journal of surgery case reports.  276-280. 

diana mellisa dualim, loo guo hou, reynu rajan. nik ritza kosai nik mahmood.  (2019).  jejunal gist: hunting down an unusual cause of gastrointestinal bleed using double balloon enteroscopy. a case report.  - international journal of surgery case report.  303-306. 

loo gou hou, reynu rajan, nik ritza kosai nik mahmood.  (2019).  staple-line post primary sleeve gastrectomy. a two patient case series and literature review.  - annals of medicine and surgery.  72-76. 

nadiah rosly, loo guo hou, mohamad aznan shuhaili, reynu rajan, nik ritza kosai.  (2019).  oesophageal perforation following transoesophageal echocardiography: a case report on successful conservative management.  - international journal of surgery case reports.  161-164. 

nik ritza kosai nik mahmood.  (2019).  cutting away obesity.  - the health.  14-15. 

globalsurg collaborative (nik ritza kosai, reynu rajan, mustafa mohamed taher, dayang nita abdul aziz).  (2019).  global variation in anastomosis and end colostomy formation following left-sided colorectal resection.  - bjs open.  403-414. 

loo guo hou, anusha prabakaran, reynu rajan, fatimah binti mohd nor, nik ritza kosai.  (2019).  concurrent bariatric surgery and surgical resection of massive localized lymphedema of the thigh. a case report..  - annals of medicine and surgery.  53-56. 

zahra rashidbenam, mohd hafidzul jasman, pezhman hafez, guan hee tan, eng hong goh, xeng inn fam, christopher chee kong ho, zulkifli md zainuddin, reynu rajan, fatimah mohd nor,mohamad aznan shuhaili, nik ritza kosai, farrah hani imran, min hwei ng.  (2019).  overview of urethral reconstruction by tissue engineering: current strategies, clinical status and future direction.  - tissue engineering and regenerative medicine.  365-384. 

fatin hanani mazri, suzana shahar, nik ritza kosai, mohd azahadi omar, nilsiswati ramilis & reynu rajan.  (2019).  a retrospective study of weight-loss predictors following bariatric surgery in malaysian patients with obesity.  - malaysian journal of nutrition.  423-433. 

juhanis fj, reynu r, mustafa mt, mohd aznan s, iman g, nik ritza k.  (2019).  internal hernia after roux en y gastric bypass: a paradigm shift of practice.  - surgical chronicles.  140-143. 

amir am, iman g, mustafa mt, nik ritza k.  (2019).  ebv-positive gastric carcinoma with lymphoid stroma: a novel variant gastric neoplasm predicting good patient's prognosis.  - surgical chronicles.  82-84. 

mustafa mohammed taher, nik ritza kosai, dayang nita abdul aziz, reynu rajan.  (2018).  surgical site infection after gastrointestinal surgery in high-income, middle-income and low-income countries: a prospective, international, multicentre cohort study.  - lancet infectious disease.  . 

m. azman, n. sze yin, m mat baki, a. sani, n.r. kosai.  (2018).  surgical versus conventional weight loss therapy for obstructive sleep apnea, a randomized controlled trial: quantitative and qualitative outcome.  - 9th isss international surgical sleep society meeting.  . 

reynu rajan, nik ritza kosai.  (2018).  history and progress of bariatric surgery in malaysia.  - obesity surgery.  . 

hassan s, kosai nr, reynu r, shuhaili ma, sutton pa, smith dc.  (2018).  extensive rectus sheath hematoma secondary to erroneous technique of anticoagulant injection.  - medicine & health.  291-295. 

chik ian, razman jarmin, affirul ariffin, hairol othman, zamri zuhdi, azlanudin azman, nik ritza kosai nik.  (2018).  a less invasive method of reducing the incidence of post-endoscopic retrograde cholangiopancreatography pancreatitis: intravenous diclofenac sodium versus placebo.  - asian journal of pharmaceutical and clinical research.  140-144. 

zahra rashidbenam, mohd hafidzul jasman, reynu rajan, fatimah mohd nor, guan hee tan, eng hong goh, xeng inn fam, christopher chee kong ho, mohamad aznan shuhaili, nik ritza kosai, zulkifli md zainuddin, min hwei ng.  (2018).  hypoxic preconditioning of adipose-derived mesencymal stem cells upregulates expression of extracellular matrix proteins.  - regenerative research.  . 

gendeh hs, taher mm, kosai nr, bs gendeh, muhammad ramzisham ar, das s.  (2018).  early buried bumper syndrome: bump it before you get buried.  - surgical chronicles.  . 

alfizah hanafiah, muhammad hafiz, asif sukri, raja affendi raja ali, nik ritza kosai, mohamad aznan shuhaili, mustafa mohammed taher.  (2018).  immunophenotyping of gastric cancers and non-gastric cancers using cluster of differentiation (cd) antibody microarray.  - 8th regional conference on molecular medicine in conjunction with 4th national conference for cancer research.  . 

kavitha subramaniam, wah-yun low, peng-choong lau, kin-fah chin, karuthan chinna, nik ritza kosai, mustafa mohammed taher, and reynu rajan.  (2018).  eating behaviour predicts weight loss six months after bariatric surgery: a longitudinal study.  - nutrients.  1-13. 

antimicrobial stewardship committee hctm ukm.  (2018).  hctm ppukm surgical prophylaxis guide 2018.  - .  73. 

globalsurg collaborative, dayang nita abdul aziz, mustafa mohamed, reynu rajan, nik ritza kosai..  (2018).  management and outcomes following surgery for gastrointestinal typhoid: an international, prospective, multicentre cohort study.  - world journal of surgery.  . 

hui ying khoo, kelvin voon, keat how teoh, shyang yee lim, premnath nagalingam, mohamad aznan shuhaili, reynu rajan, mustafa mohammed taher, nik ritza kosai.  (2018).  esophageal cancer in malaysia: the need for early detection.  - disease of the esophagus.  . 

globalsurg collaborative, nik ritza kosai, mustafa taher, reynu rajan.  (2018).  laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.  - surgical endoscopy.  . 

muhammad adi syazni, hardip singh gendeh, nik ritza kosai, mohd ramzisham abdul rahman, balwant singh gendeh, normala basiron, farrah hani imran.  (2017).  follicular thyroid cancer with sternal metastasis-challenges and outcomes.  - medical journal of malaysia.  80-82. 

nik kosai , anitha haniffa, razman jarmin, srijit das, reynu rajan, hanafiah harunarashid.  (2017).  paget-schroetter syndrome in 52-year-old male:an interesting case report.  - journal of krishna institute of medical sciences university.  104-106. 

nik ritza kosai nik mahmood.  (2017).  pembedahan bariatrik tangani diabetes.  - harian metro.  20. 

nik ritza kosai bin nik mahmood.  (2017).  surgery for diabetes?.  - the star.  9. 

reynu r, kosai nr.  (2017).  innovations in obesity and metabolic surgery:boon or bane?.  - medicine & health.  1-3. 

reynu r, neeraj k, kosai nr.  (2017).  single incision laparoscopic bariatric surgery:challenging the conventional.  - medicine and health.  143-149. 

gendeh hs, imran fh, kosai nr, gendeh bs, ramzisham ar, kelly eg.  (2017).  left facial tumour. what is it?.  - medicine and health.  154-155. 

nik ritza kosai.  (2017).  3rd international conference on advances in medical science 2017.  - adenocarcinoma of the gastro-oesophageal junction : the rise of a silent killer.  . 

zainal adwin zainal abidin, nik ritza kosai, mustafa mohd taher, iman ghoneim, mohd aznan shuhaili, nur yasmin yaacob, reynu rajan.  (2017).  a randomised controlled trial comparing the use of omega-3 polyunsaturated fatty acid supplements versus very low calorie dietary restriction in obese malaysian patients awaiting bariatric surgery.  - annals of laparoscopic and endoscopic surgery.  1-7. 

nik ritza kosai nik mahmood.  (2017).  bariatric surgery : timing.  - liver update 2017.  . 

ng chong beng, nik ritza kosai, lim shyang yee, srijit das, subasri a, reynu rajan.  (2017).  perianal ulcer and diabetes insipidus : a rare presentation of langerhans cell histiocytosis in an adult male.  - online journal of health and allied science.  1-3. 

zar chi thent, chiranjib chakraborty, pasuk mahakkanukrauh, nik ritza kosai nik mahmood, reynu rajan and srijit das.  (2017).  the molecular concept of atheromatous plaques.  - current drug targets.  1250-1258. 

tan han loong, ngiu chai soon, nik ritza kosai nik mahmood, jeevinesh naidu, rafiz abdul rani, nazefah abdul hamid, marjanu hikmah elias, isa mohamed rose, azmi tamil, norfilza m. mokhtar, raja affendi raja ali.  (2017).  serum pepsinogen and gastrin 17 as potential biomarkers for pre malignant lesions in the gastric corpus.  - biomedical reports.  460-468. 

ngo choon woon, nik ritza kosai, razman jarmin, mohd aznan shuhaili, mustafa mohd taher , reynu rajan.  (2017).  double trouble: cocurrent sigmoid volvulus and gastric volvulus in alzheimer`s disease.  - online journal of health and allied sciences.  . 

asif sukri, alfizah hanafiah, nik ritza kosai, mustafa mohamed taher and isa mohamed rose.  (2017).  distribution of gastric adenocarcinoma subtypes in different ethnicities in kuala lumpur, malaysia.  - malaysian journal of pathology.  235-242. 

dayang anita aa, gendeh hs, gendeh mk, kosai nr, mohd ramzisham ar, reynu r..  (2017).  the end of catheter dislodgement? three facile steps to secure a tunneled central venous catheter.  - medicine & health.  375-377. 

w. liew, y. y. wai, n. r. kosai, h. s. gendeh.  (2017).  tackers versus glue mesh fixation: an objective assessment of postoperative acute and chronic pain using inflammatory markers.  - hernia.  549-554. 

j h lai, ms aznan, r reynu, mm taher, h firdaus, nr kosai.  (2017).  non-umbilical metastasis of a pancreatic adenocarcinoma: case report and review of literature.  - surgical chronicles.  . 

hanafiah harunarashid, farrah-hani imran,, nik ritza kosai.  (2017).  chapter 17: skin incisions.  - at a glance series (oxford, england).  38-39. 

mohammed hamad, reynu rajan, nik kosai, paul suttol, srijit das, hanafiah harunarashid.  (2016).  retained fractured fragment of a central venous catheter: a minimally invasive approach to safe retrieval.  - ethiopian journal of health sciences.  85-88. 

asif sukri, alfizah hanafiah, nik ritza kosai, mustafa mohamed taher and isa mohamed rose.  (2016).  surface antigen profiling of helicobacter pylori-infected and -uninfected gastric cancer cells using antibody microarray.  - helicobacter.  417-427. 

a. bhangu, ......, nr kosai, m taher, r rajan.....globalsurg collaborative.  (2016).  mortality of emergency abdominal surgery in high-, middle- and low-income countries.  - british journal of surgery.  971-988. 

hl tan, cs ngiu, nr kosai, j naidu, r abdul rani, mh elias, nm mokhtar, na hamid, ra raja ali.  (2016).  the application of serum biomarkers to detect pre-malignant lesions in gastric corpus.  - annual scientific congredd of the malaysian society of gastroenterology and hepatology.  . 

m mohd sukri, a hanafiah, n nik mahmood, mmohamed taher, i mohamed rose, r mohamed.  (2016).  distribution of cd antigens in gastric adenocarcinoma cell line infected with different caga genotypes of helicobacter pylori strains.  - helicobacter.  115-116. 

n.r kosai , r reynu ,h.s gendeh, srijit das, m. lakdawala.  (2016).  concurrent mesh repair of a morgagni and umbilical hernia during a laparoscopic sleeve gastrectomy in a morbidly obese individual.  - journal of krishna institute of medical sciences university (jkimsu).  87-92. 

mohammed m hajhammad , reynu rajan, nik ritza kosai, badrulhisham bahadzor.  (2016).  transmesenteric small bowel herniation causing intestinal obstruction following laparoscopic transperitoneal nephrectomy.  - formosan journal of surgery.  161-164. 

hajhamad m, reynu r, nik ritza kosai, mustafa mt, othman h.  (2016).  successful conservative management of pancreatica-colonic fistula following videoscopis assisted retroperitoneal debridement of infected pancreatic necrosis.case report and review of literature..  - brunei darussalam journal of health.  108-113. 

nik ritza kosai, hardip singh gendeh, jing liang ho, yi rong chiew, mustafa mohamed taher, paul anthony sutton.  (2016).  laparoscopic totally transhiatal diverticulectomy of giant epiphrenic oesophageal diverticulum.  - eastern journal of medicine.  141-144. 

mohd firdaus, hardip singh gendeh, nik ritza kosai, farrah hani imran, ramzisham abdul rahman.  (2016).  an innovative technique for surgical positioning in head and neck surgery.  - medicine and health.  101-104. 

hardip singh gendeh, farrah hani imran, muhammad razif muhammad yunus, nik ritza kosai.  (2016).  a rare oro-maxillo-ocular facial cleft.  - journal of surgical academia.  55. 

hardip singh gendeh, farrah hani imran, nik ritza kosai, balwant singh gendeh, ramzisham abdul rahman, endah kelly.  (2016).  left facial tumour. what is it?.  - medicine and health.  319. 

hardip singh gendeh, bmbs, avinesh singh bhar, mbbs, manvin kaur gendeh, mbchb, hayati yaakup, mmed, balwant singh gendeh, famm, nik ritza kosai, frcs, ramzisham abdul rahman, ms.  (2016).  caring for the dying in a developing country, how prepared are we?.  - medical journal of malaysia.  259-263. 

jagwani a.v., reynu r., bin affirul a.c., mustafa m.t., kosai n.r..  (2016).  resolution of acanthosis nigricans following curative gastric carcinoma resection.  - clinica terapeutica.  99-100. 

dharmaraj b., kosai n.r., gendeh h., ramzisham a.r., das s..  (2016).  a prospective cohort study on quality of life after endoscopic thoracic sympathectomy for primary hyperhidrosis.  - clinica terapeutica.  67-71. 

reynu r, zainal za, kosai nr.  (2016).  pre-operative methods to reduce liver volume:a randomised controlled trial comparing the use of omega-3polyunsaturated fatty acid supplements vs vlcd restriction in patients awaiting bariatric surgery.  - obesity surgery.  122-123. 

reynu r, hisham ahk, kosai nr.  (2016).  concurrent minimally invasive repair of ventral hernia during laparoscopic sleeve gastrectomy : a prospective study.  - obesity surgery (ifso).  251. 

reynu r, hilal z, kosai nr.  (2016).  early effect of bariatric surgery on serum renin-aldosterone, blood pressure and weight: a prospective study in obese malaysian population.  - obesity surgery (ifso).  282-283. 

shabbir a, bc tai, lakdawala m, huang ck, praveen raj p, sby jimmy, eng a, lomanto d, cheng ak, rao j, rajan r, delko t, kosai n, k kasama, kow l, wei-jei lee.  (2016).  influence of asian ethnicity on weight loss 3 years following laparoscopic sleeve gastrectomy.  - obesity surgery (ifso).  349. 

mohd firdaus ca, reynu r, kosai nr.  (2016).  the effect of crura reinforcement on gastro-oesophageal reflux disease score following laparoscopic sleeve gastrectomy; a randomised controlled trial.  - obesity surgery (ifso).  550-551. 

elsa jr, reynu r, kosai nr.  (2016).  the effect of laparoscopic bariatric surgery on serum fibrinogen level : a prospective study in obese malaysian population.  - obesity surgery (ifso).  552-553. 

hardip singh gendeh, noor dina hashim, mohd razif mohammad yunus, balwant singh gendeh, nik ritza kosai.  (2016).  the sequelae of barium aspiration.  - anz journal of surgery.  . 

nr kosai, r reynu, at hizami, g tikfu.  (2015).  comparative study between laparoscopic sleeve gastrectomy and laparoscopic banded gastric plication in malaysia.  - obesity surgery (ifso).  324. 

r reynu, nr kosai, a haniffa.  (2015).  predicting diabetes remission following laparoscopic bariatric surgery in morbid obesity: a malaysian experience.  - obesity surgery (ifso).  323-324. 

r reynu, nr kosai, mt mustafa, lakdawala ma.  (2015).  concurrent laparoscopic mesh repair of a morgagni hernia, umbilical hernia and sleeve gastrectomy in a morbidly obese individual.  - obesity surgery (ifso).  322-323. 

nr kosai, r rajan, ej roslani, pa sutton, m mustafa, s das.  (2015).  laparoendoscopic transgastric enucleation of an awkwardly sited peri-cardial gastrointestinal stromal tumour (gist): a multi- modal approach.  - clinica terapeutica.  248-252. 

siow lr, naresh g, kosai n r, harrunarashid h, p a sutton, zainal aa.  (2015).  accuracy of handheld continous wave - doppler ultrasound in the assessment of varicose veins.  - journal of surgical academia.  16-28. 

nik ritza kosai.  (2015).  shifting the paradigm: from bariatric surgery to metabolic surgery.  - journal of surgical academia.  1-2. 

nik kosai, reynu rajan, srijit das.  (2015).  platelet changes in healthy male smokers.  - saudi medical journal.  1501. 

gendeh hs, kosai nr, belani lk, taher mm, reynu r, ramzisham ar.  (2015).  an abdominal mass: a case of jekyll and hyde?.  - medicine & health.  156-158. 

kosai nr, khan a, mustafa mt, zalizawati za, mohd firdaus ca, leong jh.  (2015).  a rare case of a gastro-peritoneal fistula following laparoscopic sleeve gastrectomy successfully treated with endoscopic stenting.  - medicine & health.  159-164. 

gendeh hs, kosai nr, belani lk, taher mm, reynu r, ramzisham ar.  (2015).  an abdominal mass: a case of jekyll and hyde.  - medicine & health.  156-158. 

shahril k, reynu r, kosai nr, bong jj , rozman z, yazmin y, mohd ramzisham ar.  (2015).  inferior vena cava tumour thrombectomy by novel endovascular approach.  - medicine & health.  151-155. 

reynu r, zairul ma, kosai nr, levin kb, das s.  (2015).  a rare presentation of caviar appendix in an amyand`s hernia.  - brunei international medical journal.  209-213. 

nik kosai, reynu rajan, srijit das.  (2015).  knowledge and attitude of nursing personnel towards depression in general hospitals: the korean perspective.  - journal of korean medical science.  209-1210. 

kosai n, gendeh h, norfaezan a, razman j, sutton p, das s.  (2015).  prolapsing gastric polyp causing intermittent gastric outlet obstruction.  - international surgery.  1148-1152. 

lks christopher, nr kosai, r reynu, kb levin, mm taher, pa sutton, n sukor, s das.  (2015).  effect of exercise on pulmonary function test in obese malaysian patients.  - la clinica terapeutica.  105-109. 

nr kosai, h amin-tai, hs gendeh, s salleh, r reynu, mm taher, pa sutton, s das.  (2015).  pregnant and serve acute abdominal pain: a surgical diagnostic dilemma.  - la clinica terapeutica.  110-113. 

christodoulidou m, kosai nr, rajan r, hassan s, das s, sutton pa, varghese j.  (2015).  does mesh augmentation of the hiatal repair with gore bio-a® improve symptomatic outcomes in laparoscopic fundoplication?.  - international medical journal of malaysia.  43-48. 

kosai nr, levin kb, reynu r, taher mm, ali rar, palaniappan s.  (2015).  snapshot quiz 15/1 (small bowel adenocarcinoma in crohn`s disease).  - british journal of surgery.  4-15. 

r reynu, nr kosai.  (2015).  predicting remission of type 2 diabetes mellitus following laparoscopic bariatric surgery in morbidly obese malaysians: a randomised controlled trial.  - 4th national & 1st mediterranean congress on surgery for morbid obesity and metabolic disorders.  . 

alfizah hanafiah, asif sukri, nik ritza kosai, mustafa mohamed taher, isa mohamed rose.  (2015).  distinct cd antigens expression in helicobacter pylori-infected and -uninfected gastric cancer patients.  - gut 2015: annual scientific congress of malaysian society of gastroenterology & hepatology.  . 

asif sukri, alfizah hanafiah, nik ritza kosai, mustafa mohamed taher, isa mohamed rose.  (2015).  cd antigen expression in helicobacter pylori-infected patients with chronic gastritis and gastric cancer.  - minggu penyelidikan perubatan & kesihatan ke-17.  . 

asif sukri, alfizah hanafiah, nik ritza kosai, mustafa mohamed taher, isa mohamed rose.  (2015).  distinct helicobacter pylori caga genotypes induced different immunopheotypic changes of cd antigens in gastric adenocarcinoma cell line.  - minggu penyelidikan perubatan & kesihatan ke-17.  . 

r rajan, lks christopher, nr kosai, l kesu balani, m mohammed taher, s das, pa sutton.  (2015).  improvement of pulmonary function following a structured exercise regime in obese population: a universuty hospital experience in malaysia.  - 46th world congress of surgery international society of surgery 40th rsct annual scientific congress.  . 

mm taher, nrk nik mahmood, aa wahidy, r rajan.  (2015).  stump appendicitis : diagnosis dilemma and technical challenge.  - 46th world congress of surgery international society of surgery 40th rsct annual scientific congress.  . 

elsa r, reynu r, kosai n r, yugasaravanan k.  (2015).  laparoscopic transgasrtic enucleation of a peri-cardial gastrointestinal stomal tumour (gist).  - annual scientific meeting college of surgeons academy of medicine of malaysia.  . 

r reynu, n r kosai, m t mustafa, k w chan.  (2015).  breast-esophagus syndrome: esophageal metastasis from invasive ductal carcinoma of breast.  - annual scientific meeting college of surgeon academy of medicine of malaysia.  . 

n r kosai, h s gendeh, m t mustafa, r reynu.  (2015).  an innovative method of managing early buried bumper syndrome.  - annual scientific meeting college of surgeon, academy of medicine of malaysia.  . 

a haniffa, r reynu, n r kosai.  (2015).  comparison between laparoscopic sleeve gastrectomy and laparoscopic roux-en-y gastric bypass in predicting the remission of type 2 diabetes mellitus in morbidly obese population.  - annual scientific meeting college of surgeon,academy of medicine of malaysia.  . 

a t hizami, r reynu, n r kosai, m t mustafa, g tikfu.  (2015).  laparoscopic sleeve gastrectomy versus laparoscopic banded gastric plication: a combined university hospital experience.  - college of surgeon, academy of medicine of malaysia.  . 

nik ritza kosai nik mahmood.  (2015).  surgery and endoscopic therapy as the new treatment option for metabolic syndrome and diabetes: a paradigm shift.  - 2nd international conference on advances in medical science (icams).  . 

n kosai, y yussra, p a sutton, h f shabbar, r razrim, t mustafa, a tamil, r reynu.  (2015).  the early outcomes of a randomized single blinded prospective study of laparoscopic inguinal hernia repair: tac fixation versus self adhesive mesh.  - 1st world conference on abdominal wall hernia surgery.  . 

divya vanoh, suzana shahar, nik ritza kosai nik mahmood.  (2015).  association between nutrient adequacy and psychosocial factors with overall rate of weight loss after bariatric surgery.  - asia pacific journal of clinical nutrition.  610-619. 

mm taher, nr kosai, gendeh hs.  (2014).  creative treatment of early buried bumper syndrome.  - annals of the royal college of surgeons.  621-622. 

r jarmin, z zuhdi, a azman, y yusoff, ac ariffin, nrn kosai, h othman, r rahim.  (2014).  early experience of the lateral approach for laparoscopic splenic preserving distal pancreatectomy.  - hpb ( journal of internation hepato-pancreatico-biliary association).  642. 

reynu r, kumar r, kosai n r, farizal f, shuhaili ma, razman j, shahizon amm.  (2014).  vein of galen malformation.  - medicine & health.  155-156. 

kosai nr , reynu r, abdikarim m, jasman mh, taher mm, idris ma, harunarashid h.  (2014).  multiple acute aortic dissection in a young adult.  - medicine & health.  143-149. 

razman jarmin, zamri zuhdi, hairol othman, yussra yusoff, affirul chairil ariffin, razrim rahim, azlanuddin azman, nik ritza nik kosai.  (2014).  the management of acute cholecystitis in pregnancy.  - hpb journal.  340. 

reynu r, kosai nr, aznan m, taher mm.  (2014).  uncommon presentation of a common aesthetic procedure: late infection of a ruptured silicone breast implant.  - medicine and health.  85-88. 

r.f. jailani, n.r. kosai, n.y. yaacob, r. jarmin, p. sutton, h. harunarrashid, j. murie, s. das.  (2014).  transarterial angioembolization versus surgery after failed endoscopic therapy for non-variceal upper gastrointestinal bleeding.  - la clinica terapeutica.  243-247. 

yin-ping wong, fazarina mohammed, nik ritza kosai, mustafa mohammed taher, nurismah md isa.  (2014).  a case of thyroid transcription factor-1 (ttf-1) positive primaryn euroendocrine carcinoma of oesophagus: a potential diagnostic caveat.  - malaysian journal of pathology.  86. 

nik ritza kosai, h. s. gendeh, m. noorharisman, paul anthony sutton, srijit das.  (2014).  a case of closed loop small bowel obstruction within a strangulated incisional hernia in association with an acute gastric volvulus.  - acta medica.  83-86. 

h anitha, y f lam, p a sutton, n r kosai, srijit das.  (2014).  refeeding syndrome: the danger of feeding a starving man.  - clinica terapeutica.  165(4):. 

m abdikarim, s shahari, m a idris, h hanafiah, n r kosai, s das.  (2014).  misdiagnosed infected aneurysm presenting as pyrexia of unknown origin (puo).  - clinica terapeutica.  165(4):143-145. 

thu, y; barakatun nisak, m; chin, y; gee, t; rohana, a; nik, r.  (2014).  comparison study between bariatric surgery and conventional treatment on nutritional status and quality of life among morbidly obese malaysian patients.  - obesity reviews.  15(S2):135. 

nr kosai, hs gendeh, mm taher, r reynu.  (2014).  a creative treatment to treating early buried bumper syndrome.  - msgh annual scientific congress & ecco educational workshop.  . 

nr kosai, hs gendeh, mm taher, pa sutton.  (2014).  laparoscopic totally transhiatal diverticulectomy of giant epiphrenic oesophageal diverticulum.  - agm & annual scientific meeting.  . 

nur afdzillah ar, gendeh h, zulkifli i, nik ritza kosai nm, sagap i.  (2014).  blatchford and rockall scores in predicting ugib severity in single tertiary centre, experience in 50 consecutive urgent ogds: a prospective observational study.  - agm & annual scientific meeting.  . 

sm rusli, mm taher, nr kosai.  (2014).  body mass index and obstructive sleep apnoea.  - agm & annual scientific meeting.  . 

arvind jagwani, nr kosai, mm taher.  (2014).  bariatric surgery on the outcome of hypertension.  - agm & annual scientific meeting.  . 

anitha h, kosai n.  (2014).  surgical treatment of type 2 diabetes mellitus.  - agm & annual scientific meeting.  . 

jh soh, mustafa taher, nik ritza kosai.  (2014).  prevalence of cardiac dysfunction among morbidly obese and metabolic syndrome patients.  - agm & annual scientific meeting.  . 

nr kosai, mm taher, kb levin, ct tang, yc lim.  (2014).  synchronous gastric carcinoma and pancreatic tumors.  - agm & annual scientific meeting.  . 

hs gendeh, nr kosai, sa watson, r kumari.  (2014).  cancer stem cells and chemoresistance in breast, prostate and colon cancer.  - agm & annual scientific meeting.  . 

nik ritza kosai.  (2014).  bariatric surgery in asia and malaysia.  - agm & annual scientific meeting.  . 

kosai nr.  (2013).  is bariatic surgery the cure for diabetes mellitus?.  - medicine and health.  52-54. 

nik ritza kosai nik mahmood.  (2013).  are we ready for bariatric surgery in treating patients with nafld? the debate: proponent.  - 10th liver update 2013 international conference.  . 

y yussra, h f shaba, n kosai.  (2013).  early outcome on randomized single blinded prospective study of laparoscopic inguinal hernia repair : tac fixation versus self adhesive mesh.  - annual general meeting & annual scientific meeting.  . 

nm nik kosai, m taher, c p ooi, z suehazlyn, s norlela, s norlaila, aw norasyikin, o ahmad marzuki, s mohammad arif, m azura dina, ws wan juani, k nor azmi.  (2013).  outcome of bariatric surgery following failed conservative weight management: the universiti kebangsaan malaysia medical centre experience.  - the 17th afes congress.  . 

cp ooi, nik kosai nm, m taher, z suehazlyn, s norlela, m norlaila, aw norasyikin, mohammad arif, o ahmad marzuki, ar anilah, m azura dina, ws wan juani, k nor azmi.  (2013).  comparing bariatric surgery versus non-surgical treatments experience in universiti kebangsaan malaysia medical centre.  - the 17th afes congress.  . 

ooi cp, suehazlyn z, nm nik kosai, m taher, aw norasyikin, s norlela, m norlaila, o ahmad marzuki, s mohammad arif, ar anilah, m azura dina, ws wan juani, k nor azmi.  (2013).  the multidisciplinary endocrine obesity clinic : the universiti kebangsaan malaysia medical centre experience with non-surgical weight loss management.  - the 17th asean federation of endocrine societies congress.  . 

nik ritza kosai nik mahmood.  (2013).  parietex progriptm self-fixating mesh in laparoscopic hernia repair.  - .  . 

nik ritza kosai nik mahmood.  (2013).  tingkatkan peluang untuk hidup.  - kompilasi majalah isihat & mingguan malaysia.  . 

nur hasyimah othman, dr nik ritza kosai nik mahmood.  (2013).  mengapa sakit perut?.  - isihat.  . 

rafidah rosli, nik ritza kosai.  (2013).  makanan masin rangsang serangan kanser esofagus.  - isihat.  . 

m.y. mohd rizal, n.r. kosai, p.a. sutton, z. rozman, j. razman, h. harunarashid, s. das.  (2013).  arterial embolization of a bleeding gastric dieulafoy lesion : a case report.  - clinica terapeutica.  25-27. 

yussra y, sutton pa, kosai nr, razman j, mishra rk, harunarashid h, das s.  (2013).  single incision laparoscopic surgery (sils) inguinal hernia repair - recent clinical experiences of this novel technique.  - clinica terapeutica.  425-428. 

s. farag, p sutton, k. s. leow, n. r. kosai, j razman, h. hanafiah, s. das.  (2013).  persistent mullerian duct syndrome: an interesting case report.  - la clinica terapeutica.  164(4):323-326. 

noorharisman, pa sutton, nik kosai, hanafiah harunarashid, srijit das, j razman.  (2012).  managing the challenges of crohn`s disease with a complex enterocutaneous fistula: an approach to reconstructive surgery.  - british journal of medical and health sciences.  1(1):89-98. 

j evans, n kosai, m onwudike, h harunarashid, s das, s shahari.  (2012).  the clinical and cost effectiveness of three day limb compression with coban following surgery on varicose veins.  - international medical journal.  19(4):337-338. 

noorharisman, pa sutton, nr kosai.  (2012).  managing the challenges of chron`s disease with complex enterocutaneous fistula: an approach to reconstructive surgery.  - annual scientific meeting of the malaysian society of gastroenterology and hepatology.  . 

my rizal, nr kosai, rozman, j razman, h hanafiah, srijit das.  (2012).  arterial embolization of a bleeding gastric dieulafoy lesion: a case report.  - annual scientific meeting of the malaysian sociaety of gastroenterology and hepatology 2012.  . 

fj ruhi, y yazmin, r razrim, z rozman, j razman, mr dzulkhairi, nr kosai.  (2012).  a comparison of transarterial angioembolization versus surgery after failed endoscopic therapy for non variceal upper gastrointestinal bleeding.  - annual scientific meeting of the malaysian society of gastroenterology and hepatology.  . 

noorharisman, pa sutton, nr kosai.  (2012).  a case of closed loop small bowel obstruction within a strangulated insional hernia and an associated with an acute gastric volvulus.  - annual scientific meeting of the malaysian society of gastroenterology and hepatology.  . 

fj ruhi, nr kosai, j razman.  (2012).  where is the portal vein?.  - msgh e-bulletin.  . 

noor hidayah shafiee, nik ritza kosai.  (2012).  bedah & buang perut: tingkatkan peluang untuk hidup.  - isihat.  . 

razman jarmin, azlanuddin azman, razrim rahim, nik ritza kosai and srijit das.  (2012).  a rare case of intussusception associated with metastasize small cell carcinoma of lung.  - acta medica iranica.  50(11):782-784. 

y yussra, nr kosai, r razrim, a azlan, j razman.  (2011).  early experience of the lateral approach for laparoscopic splenic preserving distal pancreatectomy.  - annual general meeting & annual scientific meeting.  . 

nor faezan ar, azlanudin a, razrim r, nr kosai.  (2011).  prolapse of gastric polyps causing intermittent, recurrent gastric outlet obstruction.  - annual scientific meeting of the malaysian society gastroenterology and hepatology.  . 

kosai nr, razrim r, varghese t.  (2011).  laparoscopic trans-abdominal pre-peritoneal (tapp) inguinal hernia repair using a novel self-adhesive mesh..  - college of surgeon annual scientific meeting.  .