HIV diarrhea

Background

  • Chronic diarrhea (over 28 days); can be presenting symptom of AIDS
  • Less common after introduction of HAART
  • Acute diarrhea common with normal and low CD4

HIV Associated Diseases by CD4 Level

CD4 Count Stage Diseases
>500 Early disease Similar to non-immunocompromised patients (Consider HAART medication side-effects)
200-500 Intermediate disease Kaposi's sarcoma, Candida, bacterial respiratory infections
<200 Late disease PCP, central line infection, MAC, TB, CMV, drug fever, sinusitis, endocarditis, lymphoma, histoplasmosis, cryptococcus, PML
<100 Very late disease Cryptococcus, Cryptosporidium, Toxoplasmosis
<50 Final Stage CMV retinitis, MAC

Clinical Features

  • Ascertain whether small bowel vs large bowel diarrhea
    • Small Bowel
    • 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 infection
  • Receptive anal sex - consider local HSV, Gonorrhea, chlamlydia, entamoeba

Differential Diagnosis

CD4 200-500

  • Consider routine pathogens causing Diarrhea
    • Viruses (Norovirus, Rotavirus, Adenoviruses, Astrovirus, etc.)
    • Bacteria (Salmonella, Campylobacter, Shigella, Enterotoxigenic E. coli, C. dif, etc.)
    • Protozoa (Cryptosporidium, Giardia, Cyclospora, Entamoeba, etc.)
  • Side effect of nelfinavir and ritonavir
  • Kaposi Sarcoma
  • Cryptosporidium parvum (brief course of illness) - severe watery diarrhea
  • C. dif if antibiotic exposed

CD4<200

  • Microsporidium
  • Cryptosporidium
  • Histoplasma
  • 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)
  • Cryptococcus
  • Isospora

CD4 <50

  • Mycobacterium avium complex (MAC) - infiltration of bowel associated with malabsorption
  • CMV

HIV associated conditions

Evaluation

  • Many workups will be non diagnostic
  • Start with stool WBCs, cultures, Ova and Parasites x3, C. Dif 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 workup is negative and severely immunocompromised
    • Small bowel biopsy to look for MAC, lymphoma, or Microsporidiosis
    • Guaic postive stools and weight loss: consider Kaposi Sarcoma of bowel, diagnosis with colonoscopy
  • Imaging
    • Generally not helpful, but could be indicated if severe tenderness, peritonitis, concern for biliary pathology, obstructing lesions.

Management

  • Electrolyte and volume replacement
  • Early consultation of HIV service
  • Nutrition replacement in chronic small bowel disease
  • HAART
  • Generally, avoid starting antibiotics unless have specific target
  • Antimotility agents
    • loperamide
    • crofelemer (blocks chloride secretion and approved for HIV diarrhea) 125mg po bid

Disposition

  • If near normal CD4 and symptoms consistent with small bowel disease (copious, watery), may be managed as outpatient if no other admission indication
  • Severe dehydration, electrolyte abnormalities, malnutrition, fever, and hemorrhagic diarrhea all may require admission or at minimum very close HIV follow up

See Also

References

  1. Gutteridge, David L MD, MPH, Egan, Daniel J. MD. The HIV-Infected Adult Patient in The Emergency Department: The Changing Landscape of the Disease. Emergency Medicine Practice: An Evidence-Based Approach to Emergency Medicine. Vol 18, Num 2. Feb 2016.