HIV diarrhea

Background

  • Chronic diarrhea (over 28 days), can be presenting symptom of AIDS
  • Less common after introduction of HAART

Clinical Presentation

  • Ascertain whether small bowel vs large bowel diarrhea
    • Small Bowel
      • Diarrhea watery and copius
      • May have weight loss
      • Bloating, gas, cramping
      • Vit B12 deficient if terminal illeum involved
    • Large Bowel
      • Frequent small volume, possibly painful stools
      • Hematochezia - Consider opportunistic pathogens, also consider classic hemorrhagic bacteria (e. coli O157, campylobacter, shigella, salmonella, Yersinia)
  • Weight loss is concerning for infiltrative disease, opportunistic infx
  • Receptive anal sex - consider local HSV infx, Gonorrhea, Chamlydia, Entamoeba

Differential Diagnosis

CD4>200

  • Consider routine pathogens causing Diarrhea
    • Viruses (norovirus, rotavirus, adenoviruses, astrovirus, etc.)
    • Bacteria (salmonella, campylobacter, shigella, enterotoxigenic E. coli, C. difficile, etc.)
    • Protozoa (cryptosporidium, giardia, cyclospora, entamoeba, etc.)
  • Side effect of nelfinavir and ritonavir
  • Kaposi
  • Cryptosporidium parvum (brief course of illness) - severe watery diarrhea
  • C. diff if abx exposed

CD4<200

  • Microsporidium
  • Cryptosporidium
  • Lymphoma
  • Enteroaggregative Escherichia coli (EAEC) (can also affect immunocompetent children)
  • HIV can directly infiltrate bowel wall leading to diarrhea

CD4 <100

  • Cryptosporidium parvum (chronic course of illness)
  • M. tuberculosis (disseminated disease increasingly likely <100)
  • Mycobacterium avium complex (MAC) - infiltration of bowel assoc with malabsorption
  • Histoplasma
  • Cryptococcus
  • CMV
  • Isospora

Diagnosis

  • Many workups will be non diagnostic
  • Start with stool WBCs, cultures, Ova and Parasites x3, C. Diff toxin
  • Acid fast smear to assess for Cryptosporidium, Isospora, and Cyclospora
  • CD4<100 - Microsporidium more likely, test with Trichrome staining
  • Blood cultures with fungal / acid fast if disseminated disease a concern
  • Endoscopy
    • Indicated if w/u is negative and severely immunocompromised
    • Small bowel bx to look for MAC, lymphoma, or microsporidiosis
    • Guaic postive stools and weight loss, consider Kaposi Sarcoma of bowel, dx with colonoscopy
  • Imaging
    • Generally not helpful, but could be indicated if severe tenderness, peritonitis, concern for biliary pathology, obstructing lesions.

Management

Disposition

  • If near normal CD4 and symptoms consistent with small bowel disease (copius, watery), may be managed as outpatient if no other admission indication

See Also

References


UpToDate: "Evaluation of the HIV-infected patient with diarrhea"