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Persistent culture-positive Legionella infection in an immunocompromised host

Katherine M A O'Reilly1, Marguerite A Urban, Timothy Barriero

  • 1Department of Medicine and Therapeutics, St. Vincent's University Hospital, Dublin, Ireland.

Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America
|April 22, 2005
PubMed

Insights

This case study highlights a prolonged Legionella infection in an immunocompromised patient. Despite persistent bacterial isolation, the patient achieved full recovery with appropriate antimicrobial therapy.

Area of Science:

  • Medical Microbiology
  • Infectious Diseases
  • Pulmonology

Background:

  • Legionella pneumophila is a significant pathogen causing both community-acquired and hospital-acquired pneumonia.
  • Immunocompromised individuals are at higher risk for severe Legionella infections.

Observation:

  • A case of severe pneumonia in an immunocompromised patient is presented.
  • Legionella species were consistently isolated from sputum cultures for 30 days.
  • The patient received antimicrobial treatment considered appropriate for Legionella.

Findings:

  • Despite persistent positive cultures, the patient showed clear clinical improvement in respiratory status.
  • Complete recovery was achieved following the course of treatment.

Implications:

  • This case underscores the importance of considering Legionella in severe pneumonia, even with prolonged positive cultures.
  • Clinical improvement can occur despite persistent microbiological evidence of infection.
  • Further research may be needed to understand the host-pathogen dynamics in immunocompromised individuals with Legionella infections.

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