Researcher Profile

Researcher Profile

Walter Koltun, MD

Walter Koltun, MD

Peter and Marshia Carlino Chair in Inflammatory Bowel Disease, Department of Surgery
Chief, Division of Colon and Rectal Surgery
Disease Teams:
Gastrointestinal Cancer

Research Interests

  • Crohn Disease
  • Inflammatory Bowel Diseases
  • Ulcerative Colitis
  • Therapeutics
  • Genes
  • Colonic Pouches
  • Single Nucleotide Polymorphism
  • Neoplasms
  • Diverticulitis
  • Colectomy
  • Colitis
  • Colon

Recent Publications


Gonzalez-Lopez, E, Kawasawa-Imamura, Y, Zhang, L, Huang, X, Koltun, W, Coates, M & Vrana, K 2019, 'A single nucleotide polymorphism in dopamine beta hydroxylase (rs6271(C>T)) is over-represented in inflammatory bowel disease patients and reduces circulating enzyme', PloS one, vol. 14, no. 2, e0210175.
Denson, LA, Curran, M, McGovern, DPB, Koltun, W, Duerr, RH, Kim, SC, Sartor, RB, Sylvester, FA, Abraham, C, de Zoeten, EF, Siegel, CA, Burns, RM, Dobes, AM, Shtraizent, N, Honig, G, Heller, CA, Hurtado-Lorenzo, A & Cho, JH 2019, 'Challenges in IBD Research: Precision Medicine', Inflammatory bowel diseases, vol. 25, no. 2, pp. S31-S39.
Gorrepati, VS, Stuart, A, Deiling, S, Koltun, W, Tinsley, A, Williams, E & Coates, M 2019, 'Response to the letter to the editor from dai et al, regarding "smoking and the risk of pouchitis in ulcerative colitis patients with ileal pouch anal anastomosis"', Inflammatory bowel diseases, vol. 25, no. 4, pp. E43.
Matthews, SM, Eshelman, MA, Berg, A, Koltun, W & Yochum, G 2019, 'The Crohn’s disease associated SNP rs6651252 impacts MYC gene expression in human colonic epithelial cells' PloS one, vol. 14, no. 2, e0212850.


Koltun, W 2018, '3D Modeling of the Anorectum in Fistulous Crohn's Disease: Long Overdue', Annals of Surgery, vol. 267, no. 6, pp. e108.
Schieffer, KM, Kline, BP, Harris, LR, Deiling, S, Koltun, W & Yochum, G 2018, 'A differential host response to viral infection defines a subset of earlier-onset diverticulitis patients' Journal of Gastrointestinal and Liver Diseases, vol. 27, no. 3, pp. 249-255.
Gorrepati, VS, Yadav, S, Stuart, A, Koltun, W, Messaris, E, Williams, E & Coates, M 2018, 'Anxiety, depression, and inflammation after restorative proctocolectomy', International Journal of Colorectal Disease, vol. 33, no. 11, pp. 1601-1606.
Gonzalez-Lopez, E, Imamura, Y, Walter, V, Zhang, L, Koltun, W, Huang, X, Vrana, K & Coates, M 2018, 'Homozygosity for the SCN10A polymorphism rs6795970 is associated with hypoalgesic inflammatory bowel disease phenotype', Frontiers in Medicine, vol. 5, no. NOV, 324.
Proksell, SS, Greer, JB, Theisen, BK, Davis, PL, Rosh, JR, Keljo, DJ, Goyal, A, Shah, SA, Brand, MH, Herfarth, HH, Cross, RK, Siegel, CA, Koltun, W, Isaacs, KL & Regueiro, MD 2018, 'IBD LIVE Case Series: Case 9: Do Race and Extraintestinal Manifestations Affect Treatment of Severe Crohn's Colitis?', Inflammatory bowel diseases, vol. 24, no. 4, pp. 698-713.
Kline, BP, Schieffer, KM, Choi, CS, Connelly, T, Chen, J, Harris, L, Deiling, S, Yochum, G & Koltun, W 2018, 'Multifocal Versus Conventional Unifocal Diverticulitis: A Comparison of Clinical and Transcriptomic Characteristics', Digestive Diseases and Sciences.
Schieffer, KM, Kline, BP, Yochum, G & Koltun, W 2018, 'Pathophysiology of diverticular disease', Expert Review of Gastroenterology and Hepatology, vol. 12, no. 7, pp. 683-692.
Lightner, AL, McKenna, NP, Tse, CS, Hyman, N, Smith, R, Ovsepyan, G, Fleshner, P, Crowell, K, Koltun, W, Ferrante, M, D'Hoore, A, Lauwers, N, Verstockt, B, Spinelli, A, DiCandido, F, Raffals, LE, Mathis, KL & Loftus, EV 2018, 'Postoperative outcomes in Ustekinumab- treated patients undergoing abdominal operations for Crohn's disease', Journal of Crohn's and Colitis, vol. 12, no. 4, pp. 402-407.
Stokes, AL, Kulaylat, AN, Rocourt, D, Hollenbeak, CS, Koltun, W & Falaiye, T 2018, 'Rates and trends for inpatient surgeries in pediatric Crohn's disease in the United States from 2003 to 2012', Journal of Pediatric Surgery, vol. 53, no. 7, pp. 1334-1338.
Gorrepati, VS, Stuart, A, Deiling, S, Koltun, W, Tinsley, A, Williams, E & Coates, M 2018, 'Smoking and the Risk of Pouchitis in Ulcerative Colitis Patients with Ileal Pouch-Anal Anastomosis', Inflammatory bowel diseases, vol. 24, no. 9, pp. 2027-2032.
Crowell, KT, Tinsley, A, Williams, E, Coates, M, Bobb, A, Koltun, W & Messaris, E 2018, 'Vedolizumab as a rescue therapy for patients with medically refractory Crohn's disease', Colorectal Disease.


Kulaylat, AS, Kulaylat, AN, Schaefer, EW, Tinsley, A, Williams, E, Koltun, W, Hollenbeak, CS & Messaris, E 2017, 'Association of preoperative anti-tumor necrosis factor therapy with adverse postoperative outcomes in patients undergoing abdominal surgery for ulcerative colitis', JAMA Surgery, vol. 152, no. 8, pp. e171538.
Koltun, W 2017, 'Better together: improved care of the IBD patient using the multi-disciplinary IBD center', Expert Review of Gastroenterology and Hepatology, vol. 11, no. 6, pp. 491-493.
Crowell, KT, Julian, K, Katzman, M, Berg, A, Tinsley, A, Williams, E, Koltun, W & Messaris, E 2017, 'Compliance with Clostridium difficile treatment guidelines: Effect on patient outcomes', Epidemiology and Infection, vol. 145, no. 11, pp. 2185-2192.
Schieffer, KM, Poritz, L, Yochum, G & Koltun, W 2017, 'Development of a total colectomy and ileorectal anastomosis rat model to evaluate colonic metaplasia', Journal of Surgical Research, vol. 218, pp. 217-225.
Wrafter, PF, Connelly, TM, Khan, JSA, Lucey, BC, Berg, A, Koltun, W & Joyce, WP 2017, 'Diverticular disease is associated with benign intra-abdominal cystic disease', Expert Review of Gastroenterology and Hepatology, vol. 11, no. 5, pp. 487-490.
Connelly, TM, Choi, CS, Berg, A, Harris, L, Coble, J & Koltun, W 2017, 'Diverticulitis and Crohn's disease have distinct but overlapping tumor necrosis superfamily 15 haplotypes', Journal of Surgical Research, vol. 214, pp. 262-269.
Click, BH, Greer, JB, Regueiro, MD, Hartman, DJ, Davis, PL, Siegel, CA, Herfarth, HH, Rosh, JR, Shah, SA, Koltun, W, Binion, DG, Baidoo, L & Szigethy, E 2017, 'IBD LIVE Series - Case 7: The Brain-Gut Connection and the Importance of Integrated Care in IBD', Inflammatory Bowel Diseases, vol. 23, no. 5, pp. 681-694.
Iskandar, H, Greer, JB, Krasinskas, AM, Tinsley, A, Koltun, W, Siegel, CA, Levy, LC, Herfarth, HH, Farraye, FA, Binion, DG, Rosh, JR, Keljo, DJ, Isaacs, KL & Regueiro, MD 2017, 'IBD LIVE Series - Case 8: Treatment Options for Refractory Esophageal Crohn's Disease and Hidradenitis Suppurativa', Inflammatory bowel diseases, vol. 23, no. 10, pp. 1667-1677.
Coble, JL, Yue, F, Salameh, TJ, Harris, LR, Deiling, S, Ruggiero, FM, Eshelman, MA, Yochum, GS, Koltun, WA, Gerhard, GS & Broach, JR 2017, 'Identification of a rare LAMB4 variant associated with familial diverticulitis through exome sequencing', Human Molecular Genetics, vol. 26, no. 16, ddx204, pp. 3212-3220.
Lightner, AL, Pemberton, JH, Dozois, EJ, Larson, DW, Cima, RR, Mathis, KL, Pardi, DS, Andrew, RE, Koltun, W, Sagar, P & Hahnloser, D 2017, 'In Brief', Current Problems in Surgery, vol. 54, no. 4, pp. 163-166.
Stokes, AL, Tice, S, Follett, S, Paskey, D, Abraham, L, Bealer, C, Keister, H, Koltun, W & Puleo, F 2017, 'Institution of a preoperative stoma education group class decreases rate of peristomal complications in new stoma patients', Journal of Wound, Ostomy and Continence Nursing, vol. 44, no. 4, pp. 363-367.
Schieffer, KM, Wright, JR, Harris, LR, Deiling, S, Yang, Z, Lamendellab, R, Yochum, G & Koltun, W 2017, 'NOD2 genetic variants predispose one of two familial adenomatous polyposis siblings to pouchitis through microbiome dysbiosis' Journal of Crohn's and Colitis, vol. 11, no. 11, pp. 1393-1397.
Schieffer, KM, Choi, CS, Emrich, S, Harris, L, Deiling, S, Karamchandani, D, Salzberg, A, Imamura, Y, Yochum, G & Koltun, W 2017, 'RNA-seq implicates deregulation of the immune system in the pathogenesis of diverticulitis', American Journal of Physiology - Gastrointestinal and Liver Physiology, vol. 313, no. 3, pp. G277-G284.
Schieffer, KM, Bruffy, SM, Rauscher, R, Koltun, W, Yochum, G & Gallagher, CJ 2017, 'Reduced total serum bilirubin levels are associated with ulcerative colitis', PloS one, vol. 12, no. 6, e0179267.
Schieffer, KM, Sabey, K, Wright, JR, Toole, DR, Drucker, R, Tokarev, V, Harris, LR, Deiling, S, Eshelman, MA, Hegarty, JP, Yochum, G, Koltun, W, Lamendella, R & Stewart, D 2017, 'The Microbial Ecosystem Distinguishes Chronically Diseased Tissue from Adjacent Tissue in the Sigmoid Colon of Chronic, Recurrent Diverticulitis Patients', Scientific reports, vol. 7, no. 1, 8467.
Lightner, AL, Pemberton, JH, Dozois, EJ, Larson, DW, Cima, RR, Mathis, KL, Pardi, DS, Andrew, RE, Koltun, W, Sagar, P & Hahnloser, D 2017, 'The surgical management of inflammatory bowel disease', Current Problems in Surgery, vol. 54, no. 4, pp. 172-250.


Choi, CS, Berg, A, Sangster, W, Schieffer, KM, Harris, LR, Deiling, SM & Koltun, W 2016, 'Combined Medical and Surgical Approach Improves Healing of Septic Perianal Crohn's Disease', Journal of the American College of Surgeons, vol. 223, no. 3, pp. 506-514.e1.
Choi, CS, Koltun, W & Hollenbeak, CS 2016, 'Higher mortality in surgically managed diverticulitis is associated with Asian Ethnicity and right-sided disease', Diseases of the Colon and Rectum, vol. 59, no. 3, pp. 216-223.
Sangster, W, Berg, A, Choi, CS, Connelly, TM, Chesnut, CH, Koltun, W & Stewart, D 2016, 'Outcomes of early ileocolectomy after percutaneous drainage for perforated ileocolic Crohn's disease', American Journal of Surgery, vol. 212, no. 4, pp. 728-734.
Schieffer, KM, Williams, E, Yochum, G & Koltun, W 2016, 'Review article: the pathogenesis of pouchitis', Alimentary Pharmacology and Therapeutics, vol. 44, no. 8, pp. 817-835.


Koltun, W 2015, 'Diverticulosis and colon cancer: In reply to prasad and colleagues', Journal of the American College of Surgeons, vol. 220, no. 1.
Connelly, TM, Berg, A, Iii, LH, Brinton, D, Deiling, S & Koltun, W 2015, 'Genetic determinants associated with early age of diagnosis of IBD', Diseases of the colon and rectum, vol. 58, no. 3, pp. 321-327.
Sangster, W, Kulaylat, AN, Stewart, D, Schubart, JR, Koltun, W & Messaris, E 2015, 'Hernia incidence following single-site vs standard laparoscopic colorectal surgery', Colorectal Disease, vol. 17, no. 3, pp. 250-256.
Le, PN, Greer, JB, Oikonomou, I, Schraut, WH, Siegel, CA, Cross, RK, Holubar, SD, Tinsley, A, Koltun, W, Binion, DG & Regueiro, MD 2015, 'IBD LIVE case series-case 2: Previous cancer in a patient with Crohn's disease: Is it appropriate to use biologics and immunosuppressants for IBD treatment?', Inflammatory Bowel Diseases, vol. 21, no. 6, pp. 1401-1406.
Connelly, TM & Koltun, W 2015, Molecular and genetic factors 2 in crohn's disease. in Crohn's Disease: Basic Principles. Springer International Publishing, pp. 15-33.
McAllister, BP, Williams, E, Yoo, LJ, Tinsley, A, Koltun, W, Ardell, CM, Follett, SB & Paskey, DM 2015, 'Refractory peristomal pyoderma gangrenosum successfully treated with intravenous immunoglobulin: A case report', American Journal of Gastroenterology, vol. 110, no. 12, pp. 1739-1740.
Connelly, TM, Berg, A, Harris, LR, Tappouni, R, Brinton, D, Deiling, S & Koltun, W 2015, 'Surgical diverticulitis is not associated with defects in the expression of wound healing genes' International Journal of Colorectal Disease, vol. 30, no. 9, pp. 1247-1254.
Wilson, MZ, Connelly, TM, Tinsley, A, Hollenbeak, CS, Koltun, W & Messaris, E 2015, 'Ulcerative colitis is associated with an increased risk of venous thromboembolism in the postoperative period: The results of a matched cohort analysis', Annals of Surgery, vol. 261, no. 6, pp. 1160-1166.

Clinical Trials Search

Children (age < 18 years)
Adults (age >= 18 years)