Diarrea en pacientes con hiv

Diarrhea in Patients Infected with HIV P re s e n t i n g t o t h e Emergency Department
George W. Beatty,
KEYWORDS  Diarrhea  Gastrointestinal manifestations  Opportunistic infections
MD, MPH

Diarrhea is an exceedingly common complaint in patients with human immunodeficiency virus (HIV) infection, and the severity of symptoms ranges from mild, selflimiting diarrhea to debilitatingdisease that can result in malnutrition, volume loss, and shock. Up to 40% of patients with HIV infection report at least one episode of diarrhea in a given month, and approximately one quarter of patients experience chronic diarrhea at some point.1 The prevalence of diarrhea increases with decreasing CD4 counts. More than 50% of patients with a CD4 count less than 50 cells/mm3 will experience at leastone episode of diarrhea each year, and in some areas this number will approach 100%. Approximately one-half of patients hospitalized with complications of HIV infection report diarrhea. Diarrhea has been shown to be an independent predictor of death in this population.2
CLINICAL FEATURES AND DIAGNOSIS

A useful initial approach to evaluating diarrhea in an individual infected with HIV is todistinguish between acute and chronic diarrhea, and between small and large bowel involvement (Table 1 and Boxes 1 and 2). Particular consideration should also be given to the stage of HIV disease, current medications, and sexual history, as these factors help determine likely pathogens. Evaluating the degree of systemic illness is essential to assessing the need for hospital admission. Acutediarrhea is defined as the presence of 3 or more loose or watery stools per day for 3 days to 2 weeks. Diarrhea is defined as persistent if it has been present between 2 and 4 weeks, and is considered chronic when present for 4 weeks or

Department of Medicine, University of California San Francisco, Building 80, Ward 84, 995 Potrero Avenue, San Francisco, CA 94110, USA E-mail address:gbeatty@php.ucsf.edu Emerg Med Clin N Am 28 (2010) 299–310 doi:10.1016/j.emc.2010.01.003 0733-8627/10/$ – see front matter ª 2010 Elsevier Inc. All rights reserved. emed.theclinics.com

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Table 1 Small versus large bowel diarrhea Symptoms  Large volume  Watery stool  Upper abdominal cramps  Bloating  Gas  Weight loss  Malnutrition  Dehydration  Small volumes  Frequent bowel movements Mucoid or bloody stool  Tenesmus  Lower abdominal cramps Common Pathogens  Salmonellaa  E coli  Viral (eg, rotavirus)  Giardia  MAC  Cryptosporidiuma  Microsporidiuma  Malabsorption  Yersinia  Campylobactera  Shigella  C difficile  CMV  Enteroinvasive E coli  Entamoeba histolytica  Gonorrhea

Small bowel

Large bowel

a

May involve both small and large bowel, buttypically presents as listed.

more. Pathogens infecting the small bowel affect the secretory and nutritional absorptive functions of the gastrointestinal tract, and typically present with large volumes of watery stool, often accompanied by cramps, bloating, and abdominal gas. If the diarrhea is severe or prolonged, dehydration, malnutrition, and weight loss may manifest. Large bowel involvementprimarily affects water resorptive capacity and typically causes frequent, small-volume diarrhea that may be bloody or mucoid and is often accompanied by pain. In general, diarrheal symptoms are nonspecific in patients infected with HIV, as they are in the host without HIV infection.3 Patients with bacterial diarrhea often, although not invariably, present with associated crampy abdominal pain.4 Thelack of associated abdominal pain or other symptoms should suggest viral acute gastroenteritis (AGE) or medication side effects. In patients with the large-volume watery diarrhea characteristic of small bowel infections, volume loss may result in dizziness, syncope, pallor, electrolyte imbalances (hypokalemia, hyponatremia), and acute renal insufficiency. Signs of invasive or systemic involvement...