Protein-losing enteropathy during highly active antiretroviral therapy in a patient with AIDS-related disseminated Mycobacterial avium complex infection

Protein-losing enteropathy caused by disseminated Mycobacterium avium complex infection in a patient receiving antiretroviral therapy: an autopsy case report

Background

Disseminated Mycobacterium avium complex infection is an important indicator of acquired immunodeficiency syndrome (AIDS) in patients with advanced human immunodeficiency virus (HIV) infection. Effective antiretroviral therapy has dramatically reduced the incidence of and mortality due to HIV infection, although drug resistance and poor medication adherence continue to increase the risk of disseminated M. avium complex infection. However, gastrointestinal lesions in cases of disseminated M. avium complex infection resulting in protein-losing enteropathy have been rarely discussed. Therefore, we present a case of protein-losing enteropathy caused by disseminated M. avium complex infection in a patient undergoing antiretroviral therapy.

Case presentation

A 29-year-old man was diagnosed with AIDS 4 years ago and was admitted for a 10-month history of refractory diarrhea and fever. Despite receiving antiretroviral therapy, the viral load remained elevated due to poor medication adherence. The patient was diagnosed with disseminated M. avium complex infection and started on antimycobacterial drugs 2 years before admission. However, the infection remained uncontrolled. The previous hospitalization 1 year before admission was due to hypoalbuminemia and refractory diarrhea. Upper gastrointestinal endoscopy revealed a diagnosis of protein-losing enteropathy caused by intestinal lymphangiectasia, and treatment with intravenous antimycobacterial drugs did not resolve his intestinal lymphangiectasia. The patient inevitably died of sepsis.

Conclusions

Clinical remission is difficult to achieve in patients with AIDS and protein-losing enteropathy caused by disseminated M. avium complex infection due to limited options of parenteral antiretroviral drugs. This report highlights the importance of identifying alternative treatments (such as an injectable formulation) for patients who do not respond to antiretroviral therapy due to protein-losing enteropathy with disseminated M. avium complex infection.

Patterns of Mycobacterium avium-intracellulare complex infection in duodenal endoscopic biopsies in HIV/AIDS patients

Mycobacterium avium-intracellulare complex (MAIC) is a nontuberculous opportunistic infection in immunocompromised patients. Involvement of the gastrointestinal tract (GIT) is usually part of a disseminated disease in AIDS patients with a low CD4 count, however with standard antiretroviral therapy (ART), a localized presentation is more likely. It can affect any part of the GIT, mostly the duodenum and typically as patches. Incomplete or refractory ART for HIV-strains, therapy-related side effects, noncompliant or incomplete treatment to previous MAIC infections, superimposed complications and comorbid opportunistic infections may result in atypical clinical, endoscopic and histopathologic manifestations. We performed a retrospective review study retrieving cases of MAIC in duodenal endoscopic biopsy. We found five cases of MAIC in HIV/AIDS patients. They were males with an average age of 40-years. They showed different histopathologic features, variable patterns of MAIC-histiocytic infiltrates, and varying intensity of intracellular acid-fast positive bacilli. Enterocytes vacuolization and transepithelial elimination were also observed. Three cases were associated with cytomegalovirus and cryptococcal infections. A case was complicated by lymphangiectasia-associated protein-losing enteropathy. Initially, three cases were morphologically missed. Ziehl-Neelsen stain helped reach the correct diagnosis. Pathologists have an important role in patients' management by guiding clinicians to the correct diagnosis. Pathologists should be aware of these different histopathologic manifestations, their potential pitfalls, look for certain helpful clues complemented with multiple levels and special stains. In particular, AFB stains are mandatory in all mucosal biopsy specimens from HIV/AIDS patients regardless of their appearances.

Endoscopic and imaging findings in protein-losing enteropathy

OBJECTIVES

Protein-losing enteropathy (PLE) is often difficult to diagnose. We evaluated the diagnostic yields of underlying diseases of PLE among esophagogastroduodenoscopy, colonoscopy, fluoroscopic conventional enteroclysis (FCE), videocapsule endoscopy (VCE), and double-balloon enteroscopy (DBE) and prognosis after treatment.

METHODS

Between June 2003 and August 2010, 25 consecutive patients with PLE confirmed by fecal α1-antitrypsin clearance (n=18) and technetium 99m human serum albumin scintigraphy (n=19) were enrolled, investigated, and treated.

RESULTS

Of 25 patients, 4 (16%) with intestinal lymphangiectasia secondary to macroglobulinemia (n=1), amyloidosis (n=2), and strongyloidiasis (n=1) were diagnosed at preceding esophagogastroduodenoscopy or colonoscopy, and 7 (32%) with primary intestinal lymphangiectasia and chronic nonspecific multiple ulcers unrelated to nonsteroidal anti-inflammatory drugs of the small intestine were newly diagnosed at FCE or VCE. Other 11 (44%) patients with primary intestinal lymphangiectasia, small-bowel tumors, amyloidosis, chronic nonspecific multiple ulcers unrelated to nonsteroidal anti-inflammatory drugs of the small intestine, Crohn's disease, and small-bowel ulcers due to polyarteritis nodosa were diagnosed only at DBE with biopsy. Three patients with primary intestinal lymphangiectasia, cirrhosis after living donor liver transplantation, and congestive heart failure were not diagnosed at any small-bowel examination. The overall diagnostic yield of FCE, VCE, and DBE was 62% (8/13), 83% (14/17), and 88% (22/25), respectively. Eight patients (32%) died of underlying disorders regardless of medical treatment over the follow-up period.

CONCLUSIONS

DBE with pathologic findings of biopsy specimens was useful for the differential diagnosis of PLE. Noninvasive VCE might be preferable and useful for screening and follow up of PLE without stricture. Prognosis of a subgroup of PLE was poor regardless of treatment.