What is the approach to diagnosing and treating abdominal pain in a patient with Human Immunodeficiency Virus (HIV) infection?

Diagnosis and Treatment of Abdominal Pain in HIV Patients

In HIV patients presenting with abdominal pain, obtain a contrast-enhanced CT scan as your primary imaging modality, as clinical signs and basic imaging are unreliable in this population, and measure CD4 count and viral load to stratify risk for complications. 1

Initial Diagnostic Approach

Clinical Assessment Limitations

• Clinical signs, symptoms, and laboratory tests are unreliable in HIV patients with abdominal pain—the degree of immunocompromise directly correlates with decreased reliability of physical examination findings. 1
• Fever, leukocytosis, and peritoneal signs may be mild or completely absent, especially in severely immunocompromised patients, making traditional surgical assessment inadequate. 1
• Plain radiographs and ultrasound lack sufficient sensitivity and specificity for definitive diagnosis in this population. 1

Mandatory Imaging and Laboratory Workup

• Obtain contrast-enhanced CT scan liberally as the most reliable diagnostic test for intra-abdominal disease in HIV patients, given the high mortality if surgical disease is missed. 1
• Measure CD4 count and viral load in all HIV patients with acute abdominal pain to predict postoperative complication rates and guide management decisions. 1
• Order complete blood count, serum electrolytes, liver function tests, coagulation studies, and C-reactive protein. 1
• Test for Clostridioides difficile and its toxin in any patient presenting with diarrhea, with or without acute abdomen. 1

HIV-Specific Diagnostic Considerations

• Always consider surgical diseases specifically associated with HIV, including abdominal tuberculosis and Mycobacterium avium complex infections, in your differential diagnosis. 1
• The most common causes of abdominal pain vary by location: right upper quadrant pain is most often sclerosing cholangitis (requiring ERCP for diagnosis), while diffuse abdominal pain with diarrhea frequently indicates cytomegalovirus colitis. 2
• CMV colitis should be suspected when chronic diarrhea is accompanied by abdominal pain; perform colonoscopy with biopsies of the right colon where histopathological changes are most evident. 3
• Consider CMV-related immune reconstitution inflammatory syndrome (IRIS) in patients who develop abdominal pain shortly after ART initiation, as intestinal perforations can occur without prodromal gastrointestinal symptoms. 4

Risk Stratification Based on Immune Status

CD4 Count as Prognostic Indicator

• HIV patients with CD4 count >200 cells/mm³ have mortality and morbidity rates similar to the general population and can be managed with standard surgical approaches. 1
• Worse perioperative outcomes occur in patients with lower CD4 counts and higher viral loads, requiring heightened vigilance for complications. 1
• HIV infection itself should not alter therapeutic decisions or prognostic counseling, as most preoperative prognostic factors mirror those of the general population. 1

Treatment Approach

Medical Management

• Continue antiretroviral therapy orally as long as possible when surgery is indicated, and resume it as soon as possible postoperatively. 1
• Treat neutropenic enterocolitis and typhlitis nonoperatively with broad-spectrum antibiotics and bowel rest; reserve emergency surgery only for perforation or ischemia. 1
• Use a damage control approach in severely sick immunocompromised patients with physiological derangement. 1

Surgical Indications

• Laparotomy is rarely necessary in HIV patients with abdominal pain, as most cases are due to infectious diarrhea, ileus, or organomegaly rather than true surgical emergencies. 5
• Operate emergently for documented perforation, ischemia, or uncontrolled bleeding. 1, 5
• For CMV-related intestinal perforations, early surgical intervention with partial resection and repair is lifesaving, though mortality remains high. 4

Common Pitfalls and Caveats

• Do not rely on absence of fever or peritoneal signs to rule out surgical disease—these findings are frequently absent in immunocompromised patients. 1
• Do not delay CT imaging in favor of ultrasound or plain films, as the higher mortality from missed surgical disease justifies liberal use of contrast-enhanced CT. 1
• Be aware that CMV colitis can present with marked colon wall thickening simulating pseudotumoral masses on CT scan. 3
• In patients with controlled chronic pain who report new abdominal pain, investigate thoroughly as this may represent a new acute process requiring different management. 1, 6
• Consider neoplasia (Kaposi's sarcoma, lymphoma, Burkitt's lymphoma) in the differential, as it accounts for a significant proportion of abdominal pain in HIV patients. 2, 5