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.

Chylous ascites, anti-interferon-gamma autoantibody, and angioimmunoblastic T-cell lymphoma: a rare but intriguing connection over Mycobacterium avium.

We report a case of non-AIDS (acquired immunodeficiency syndrome), non-CAPD (Continuous Ambulatory Peritoneal Dialysis), non-cirrhotic, Mycobacterium avium peritonitis, which is a rare form of mycobacterial infection. A 66-year-old Japanese man who had been treated previously for angioimmunoblastic T-cell lymphoma (AITL), had developed disseminated M. avium infection. Antimycobacterial regimen improved his symptoms; however, following an interruption in treatment, he developed chylous ascites. The patient died of uncontrolled peritonitis despite intensive treatment. Anti-interferon-γ autoantibody was positive, and AITL was presumed to be involved in autoantibody production. A rare coexistence of chylous ascites, autoantibody, and AITL taught us an intriguing lesson on the pathogenesis of M. avium infection. Particularly, we conclude that treatment strategies for M. avium infection should aim to restore immunity.

Rituximab Restores IFN-γ-STAT1 Function and Ameliorates Disseminated Mycobacterium avium Infection in a Patient with Anti-Interferon-γ Autoantibody.

A 67-year-old Japanese female with back pain and severe cachexia visited our hospital. The diagnosis was disseminated Mycobacterium avium complex infection (dMAC) with multiple bone involvement. Anti-mycobacterial chemotherapy was started, but fever persisted and dislocation of cervical vertebrae has made her bedridden. Because anti-interferon (IFN)-γ autoantibody was positive, four doses of rituximab 375 mg/m2, every 7 day, were administered. Soon after treatment, progression of osteolytic lesions and wasting has stopped. We proved that rituximab has recovered IFN-γ signaling as shown by IFN-γ-induced STAT1 phosphorylation. It can be a promising option for dMAC cases with anti-IFN-γ autoantibody.

Epidural intracranial abscesses and multiple bone metastases caused by disseminated Mycobacterium avium complex infection: illustrative case.

BACKGROUND: Mycobacterium avium complex (MAC) generally causes localized pulmonary infections in immunocompromised hosts, but rarely in other organs and tissues, which is called disseminated MAC infection. OBSERVATIONS: The authors herein present a 48-year-old male patient with disseminated MAC infectious lesions in the lungs and on the cranial, vertebral, femoral, and pelvic bones, a normal CD4 count, and immunopositivity for the interferon-ɤ (IFN-ɤ) neutralization antibody. Cranial lesions were multiple osteolytic lesions associated with abscesses in the cranial bones. The patient initially received conservative treatment with multiple antibiotics; however, cranial lesions worsened. Therefore, multiple cranial lesions were removed via osteoplastic craniectomy and the postoperative course was uneventful. Pathological findings revealed MAC infection. The patient was discharged without recurrence or complications. LESSONS: Multiple cranial MAC dissemination with immunopositivity for the IFN-ɤ antibody is rare. The authors herein present the clinical course of a rare surgical case of MAC dissemination with a literature review.