Today we discussed diarrhea in the setting of HIV.
As a general rule, whenever faced with a new (or worsened) problem in the setting of a pre-existing disease, a useful dichotomy is whether this new problem is related or unrelated to the underlying disease. Pts with underlying HIV are still "entitled" to have the more common causes of diarrhea (or any other presentation)
Diarrhea, weight loss, malnutrition, and wasting was interestingly one of the first described syndromes of what came to be known as AIDS in 1985; it was initially called "slim disease" by African populations, as this Lancet article describes
Clinically significant diarrhea occurs in about 50% of HIV-infected patients in North America. The majority of these patients have an identifyable enteric pathogen if extensive enough workup is done. There is a small subset of HIV patients with "HIV enteropathy", in whom there is no identifyable pathogen. This is likely due to the effect of HIV itself and inflammation involving the GI lymphatic tissue.
Diarrhea may be more characteristic of small bowel pathology (post-prandial, voluminous, associated with weight loss and malnutrition) or large bowel pathology (frequent, small volume, with possible blood and mucous, tenesmus).
One way to approach the MANY opportunistic and other causes of diarrhea is by CD4 count:
Any CD4 count:
Bacterial: C. Diff, salmonella, shigella, campylobacter
Mycobacterial: M. TB
Parasitic: strongyloides, cyclospora, isospora, entamoeba histolytica, giardia lamblia
CD4 below 200: all of above and
Histoplasma capsulatum
Coccidioides
CD4 below 100: all of above and
Cryptosporidium (shown above)
Microsporum
Leishmaniasis
CD4 below 50: all of above and
MAI
Cryptococcus
CMV
Treatment is generally targeted at the identified pathogen. See Table 3 in below paper for details on specific agents for each of above.
Non-specific treatments include anti-diarrheals, low fat diet, nutritional support, and avoidance of lactose
Link:
Click here for a 2009 review from Gastroenterology on HIV and diarrhea (need journal access)
