cytomegalovirus colitis; CMV colitis

Etiology

• cytomegalovirus infection in patients with HIV1 infection/AIDS
  • generally due to reactivation of latent virus
• complication of refractory ulcerative colitis

Epidemiology

• CMV is the most common opportunistic pathogen causing colitis

Pathology

• colonic ulcerative lesions with intranuclear inclusions
• clean-based colonic ulcers

Clinical manifestations

• tenesmus, proctitis, abdominal pain, frequent small volume bowel movements
• bloody diarrhea in patients with refractory ulcerative colitis

Laboratory

• CD4 count < 50-100/uL
• a negative cytomegalovirus IgG in serum renders CMV colitis unlikely*

* CMV colitis is generally due to reactivation of latent virus

Diagnostic procedures

• colonoscopy
• sigmoidoscopy with biopsy for refractory ulcerative colitis
• ophthalmoscopy for CMV retinitis in patients with HIV1 infection & cytomegalovius infection

Differential diagnosis

• cryptosporidiosis: large volume watery diarrhea
• giardiasis: large volume watery diarrhea
• Mycobacterium avium complex:
  • fever, diarrhea (see HIV1-associated diarrhea)
  • no tenesmus, proctitis, ulcers
  • elevated alkaline phosphatase in serum
  • CD4 count < 50/uL
• ulcerative colitis:
  • rare in AIDS patients
  • disease may be more quiescent in HIV1 patients with CD4 count < 50/uL
• Kaposi sarcoma: submucosal hemorrhagic lesions, rarely symptomatic

Treatment:

• ganciclovir (see Cytomegalovirus)

More general terms

• diarrhea in patients with AIDS
• cytomegalovirus (CMV, human herpesvirus 5, HHV5)