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Opportunistic pneumonia: a clinicopathological study of five cases caused by an unidentified acid-fast bacterium

B H Rogers, G R Donowitz, G K Walker

    The New England Journal of Medicine
    |November 1, 1979
    PubMed

    Insights

    Opportunistic pulmonary infections caused by acid-fast bacilli were observed in five immunocompromised patients. These cases presented uniquely, mimicking other lung conditions and responding poorly to standard treatments.

    Area of Science:

    • Infectious Diseases
    • Pulmonology
    • Microbiology

    Background:

    • Opportunistic infections pose significant risks in immunocompromised individuals.
    • Acid-fast bacilli (AFB) are typically associated with tuberculosis, but can cause other infections.
    • High-dose corticosteroid therapy can impair immune function, increasing susceptibility to infections.

    Purpose of the Study:

    • To describe five cases of unusual pulmonary infections caused by acid-fast bacilli.
    • To highlight the unique clinical and pathological features of these infections.
    • To investigate the potential role of corticosteroid therapy in these cases.

    Main Methods:

    • Case series analysis of five patients with pulmonary infections.
    • Review of clinical presentations, treatment regimens, and patient histories.
    • Histopathological examination of lung biopsy or autopsy samples.
    • Microbiological cultures using routine bacterial, fungal, and mycobacterial media.

    Main Results:

    • Five patients presented with opportunistic pulmonary infections due to acid-fast bacilli.
    • Clinical presentations mimicked septic pulmonary emboli or bacterial pneumonia.
    • Infection was linked to high-dose corticosteroid therapy for renal-transplant rejection or lymphoma.
    • Histopathology revealed acute suppurative pneumonia with intracellular AFB, lacking granulomas or caseous necrosis.
    • The organism did not grow on standard culture media.

    Conclusions:

    • Acid-fast bacilli can cause unusual suppurative pneumonia in immunocompromised patients.
    • High-dose corticosteroid therapy appears to be a significant risk factor.
    • The unidentified AFB organism may represent a novel pathogen causing severe lung infections.

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