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Tractable Mammalian Cell Infections with Protozoan-primed Bacteria
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Tractable Mammalian Cell Infections with Protozoan-primed Bacteria

Published on: April 2, 2013

The compromised host and Legionnaires' disease

L D Saravolatz, K H Burch, E Fisher

    Annals of Internal Medicine
    |April 1, 1979
    PubMed

    Insights

    Legionnaires' disease in immunosuppressed patients can be severe, leading to necrotizing pneumonia. Intravenous erythromycin showed good response, with rifampin aiding further improvement in some cases.

    Area of Science:

    • Infectious Diseases
    • Pulmonology
    • Immunology

    Background:

    • Legionnaires' disease bacterium can cause severe pneumonia, particularly in immunocompromised individuals.
    • Immunosuppression in patients was linked to underlying illnesses, corticosteroid therapy, and other immunosuppressive agents.

    Purpose of the Study:

    • To describe the clinical presentation, diagnosis, and treatment outcomes of Legionnaires' disease in immunosuppressed patients.

    Main Methods:

    • Diagnosis involved culture of lung tissue and bronchial washings, direct fluorescent antibody staining, and serologic testing.
    • Treatment efficacy was assessed for oral and intravenous erythromycin, with and without rifampin.

    Main Results:

    • Eight immunosuppressed patients were diagnosed with Legionnaires' disease over seven months.
    • Clinical presentation mimicked other bacterial pneumonias in compromised hosts.
    • Two patients developed necrotizing pneumonia with abscess formation and respiratory failure.
    • Oral erythromycin was ineffective; intravenous erythromycin yielded good responses in six patients.
    • Two patients improved further with the addition of rifampin.

    Conclusions:

    • Legionnaires' disease can be severe in immunocompromised hosts.
    • Prompt diagnosis via open lung biopsy and specialized microbiologic tests is crucial.
    • Intravenous erythromycin is a viable treatment, and rifampin may offer additional benefit.

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