colitis

Definition : Colitis is an inflammation of the colon.

Images

 Pseudomembranous Colitis, Colectomy Specimen by Ed Euthman

 ipilimumab-induced colitis

• https://twitter.com/GIPathologyURMC/status/715943975526522880

Lesional patterns

 acute colitis

• congestive colitis
• common acute colitis
• pseudomembranous colitis
• hemorrhagic colitis

 active colitis

• focal active colitis
• diffuse active colitis

 chronic colitis

• lymphocytic colitis (microscopical colitis )
• granulomatous colitis
• eosinophilic colitis
• GVHD-like colitis (7832281)

Etiology

 colorectal infections : infectious colitis / infective colitis
 collagenous colitis
 allergic colitis
 eosinophilic colitis
 obstrucive colitis
 diversion colitis
 diverticular disease-associated chronic colitis
 diffuse colitis cystica profunda
 pseudomembranous collagenous colitis

 idiopathic inflammatory colitis

• Crohn colitis
• ulcerative colitis

 acute radiation colitis
 ischemic colitis
 colitis of Behcet’s syndrome
 chronic granulomatous disease (colitis in chronic granulomatous disease)
 drug-induced colitis

• ipilimumab-induced colitis
  • https://twitter.com/GIPathologyURMC/status/715943975526522880

Variants

 focal colitis

• focal active colitis

 diffuse colitis

• pancolitis

References

 Biopsy diagnosis of colitis: possibilities and pitfalls. Tsang P, Rotterdam H. Am J Surg Pathol. 1999 Apr;23(4):423-30. PMID: 10199471

 Ulcerative colitis: patterns of involvement in colorectal biopsies and changes with time. Kleer CG, Appelman HD. Am J Surg Pathol. 1998 Aug;22(8):983-9. PMID: 9706978