ACUTE ABDOMEN AND HIV/AIDS
General Considerations for GI complaints: - specific disorders often correlate with degree of immunosuppression - in advanced HIV infection, GI symptoms are usually part of systemic infection - multiple infections are common - failure to diagnose a specific cause is relatively common (in 1 study, a specific diagnosis was made premortem in only 59% of pts with abdominal pain) Evaluation of Abd pain: - Epidemiology: Abdominal pain is frequent complaint • 50% of pts develop GI manifestations during course of disease • 15% experience severe abdominal pain - these pts have an increased mortality rate - Usually, abdominal pain is directly related to HIV and its consequences (but of course common causes that occur in the general population must also be considered) - history: important for localizing pain • quality and associated symptoms should be sought - PE: • fever is sensitive sign but not very specific • orthostatics are important • w/ severe infectious diarrhea may have diffusely tender abdomen • rectal exam is very important Diagnosis: duration and severity of symptoms dictate urgency of evaluation • labs - do not always have increased WBC • CT should be used early in evaluation • may detect disease not suspected clinically (ex. gallbladder or colonic wall thickening, focal hepatic lesions, biliary duct dilation, pancreatic infiltration, abdominal adenopathy, peritoneal thickening) Causes of Acute Abdomen: (see table 1) - abdominal symptoms usually represent medical illnesses that can be treated conservatively, but at times these pts can be dramatically ill - can be very difficult to identify acute symptoms, especially in patients with chronic symptoms and w/ prior lab abnormalities 1) Intestinal Perforation: - most often due to CMV infection - most common sites include terminal ileum and colon - mechanism: mucosal vasculitis → ulceration → perforation - Colonic perforation results in pneumoperitoneum in over 90% of immunocompromised patients due to their inability to localize infection 317
- diagnosis: intranuclear inclusion bodies on biopsy of sites of perforation - treatment: appropriate surgical management depending on site of perforation - has a grave prognosis - less common causes: lymphoma, Kaposi’s sarcoma, or severe ilieocolitis from mycobacterium avium intracellular (MAI) infection 2) Intestinal Obstruction: - most likely AIDs related (young age group, and especially when no prior surgery) - causes: lymphoma (gastric outlet obstruction or SBO), SBO due to mycobacterial disease, intussusception from Kaposi’s sarcoma, and an Ogilvie-like syndrome progressing to toxic megacolon due to CMV infection 3) Peritonitis and Ascites: - Peritonitis may result from a perforated viscus or from infectious (eg. MTb, CMV, toxo, and crypto) or unclear etiology without perforation - must be able to mount an inflammatory response to develop - in pts with ascites, paracentesis is a safe procedure and often leads to diagnosis 4) Pancreatitis: - common finding in HIV pts (has been described in 4.7% of hospitalized pts with HIV) - usually complication of medications rather than from HIV infection - gallstone pancreatitis is unusual - most commonly implicated meds are pentamidine and dideoxynosine (ddI) - presentation is similar to non-HIV pts but generally more severe - death is usually due to hypoglycemia in these pts 5) Cholecystitis: - presents w/ fever and RUQ pain - usually acalculus - common etiologies: CMV and crypto - gallbladder perforation has been seen in several documented cases - can also have sclerosing cholangitis and papillary stenosis 6) Acute Appendicitis: - occurs due to classic occlusion of appendiceal orfice by a fecalith but can also be due to occlusion from Kaposi’s sarcoma or acute CMV infection - it has been reported that 30% of cases are due to AID’s related conditions - present with characteristic localizing RLQ pain - may be increased rate of perforation, gangrenous appendicitis, and initial appendiceal abscesses among these pts but unclear in literature
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7) GI bleeding: - rarely been reported - surgery required when medical measures to control bleeding have failed Enterocolitis: - most common cause of abdominal pain - multiple causes including bacteria (such as C-diff, shigella, salmonella, campylobacter, and yersinia), viruses (such as CMV, HSV, or HIV itself), and protozoa (such as cryptosporidium, microsporidium, ameobiasis, giardia, isospora) - C-diff- associated diarrhea is common in pts receiving abx (esp. clindamycin, ampicillin, and cephalosporins) - Salmonella is most frequent enteric bacterial pathogen associated with immunosuppression - hx: most useful for determining portion of GI tract that is involved - those with prolonged symptoms often develop diffuse abdominal pain, as well as fever and orthostasis, and can appear to have an acute abdomen - PE: non specific findings - diagnosis: stool exams (culture for enteric bacterial pathogens, C-diff toxin assay, ova and parasites, and an acid-fast smear to look for cryptosporidium, isospora, and cyclospora), blood cx due to high incidence of bacteremia • can do sigmoidoscopy with biopsy of abnormal appearing mucosa or randomly and/or colonoscopy • CT scan can also be useful Surgery: - indications: worsening abdominal tenderness or deteriorating clinical course - intraop: accurate identification and definitive surgical management important • creation of stoma rather than 1º anastomoses (leaks poorly tolerated) - one study: morbitiy = 50%, mortalilty = 38% • concluded that should not exclude from operation when needed References: 1) Bizer LS, Pettorino R, Ashikari A, Emergency abdominal operations in the patient with acquired immunodeficiency syndrome. J Am Coll Surg 1995 Feb;180(2):205-9 2) Katz, MH., French, DM. AIDS and the Acute Abdomen. Emerg Med Clin North Am 1989 Aug; 7(3): 575-89 3) Parenche, F, Cernushi, M, Antinori, S, et al. Severe abdominal pain in patients with AIDS: Frequency, clinical aspects, causes, and outcome. Scand J Gastroentolo 1994; 29:511 4) Scott-Conner, CEH., Fabrega, AJ. Gastrointestinal problems in the immunocompromised host, A review for surgeons. Surg Endosc. 10, 959 (1996) 5) Sharpstone, D, Gazzard, B. Gasrtointestinal manifestations of HIV infection. Lancet 1996; 348:379 6) Sabistan. Textbook of Surgery. W.B. Saunders company, Philadephia. 2001.
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Table 1 Common Abd pain syndromes Enterocolitis Etiologic agents in AIDS pts Cryptosporidium, entamoeba, giardia, isospora Shigella, slamonella, cambylobacter, yersinia, CMV, HSV, HIV CMV, KS, lymphoma, cryptosporidium, Candida MTb, CMV, histoplasmosis, toxoplasmosis, cryptosporidium, lymphoma See causes of perforation KS, lymphoma, MAC, intussesception secondary to infectious enteritis CMV, KS, shigella, salmonella, Cryptosporidium, histoplasmosis CMV, cryptosporidium CMV, cryptosporidium
Perforation Peritonitis Primary Secondary Obstruction GI bleeding Cholecystitis Sclerosing cholangitis and Papillary stenosis
Bethany Slater, MSSM IV May 8, 2003
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