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
    • Diarrhea watery and copious
    • May have weight loss
    • Bloating, gas, cramping
    • Vitamin B12 deficiency 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 infection
• Receptive anal sex - consider local HSV, Gonorrhea, chlamydia, entamoeba

Differential Diagnosis

CD4 200-500

• Consider routine pathogens causing Diarrhea
  • Viruses (Norovirus, Rotavirus, Adenovirus, Astrovirus, etc.)
  • Bacteria (Salmonella, Campylobacter, Shigella, Enterotoxigenic E. coli, C. diff, 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. diff 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

• HIV neurologic complications
  • Toxoplasmosis
  • Cryptococcosis
  • AIDS Dementia
  • Seizures in patients with HIV-AIDS
  • Primary CNS lymphoma
• HIV pulmonary complications
  • Pneumocystis jirovecii pneumonia (PCP)
  • Tuberculosis (TB)
  • CMV pneumonia
• Ophthalmologic complications
  • CMV Retinitis
  • Herpes Zoster Ophthalmicus
• Other
  • AIDS fever of unknown origin
  • Immune reconstitution inflammatory syndrome
  • HIV diarrhea
  • Esophageal candidiasis
  • Kaposi's sarcoma
  • Pruritic papular eruption of HIV
  • Hairy oral leukoplakia
• HAART medication side effects
  • HAART-induced lactic acidosis
  • Neuropyschiatric effects
  • Hepatic toxicity
  • Renal toxicity
  • Steven-Johnson's
  • Cytopenias
  • GI symptoms
  • Endocrine abnormalities

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
  • Guaiac positive 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 repletion
• 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

• HIV - AIDS (Main)
• Diarrhea

References

• UpToDate: "Evaluation of the HIV-infected patient with diarrhea"
• https://www.aids.gov/hiv-aids-basics/staying-healthy-with-hiv-aids/potential-related-health-problems/opportunistic-infections/