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Legionella pneumophila Outer Membrane Vesicles: Isolation and Analysis of Their Pro-inflammatory Potential on Macrophages
08:34

Legionella pneumophila Outer Membrane Vesicles: Isolation and Analysis of Their Pro-inflammatory Potential on Macrophages

Published on: February 22, 2017

Legionella micdadei infection presenting as severe secretory diarrhea and a solitary pulmonary mass

Boris I Medarov1, Anita K Siddiqui, Tahir Mughal

  • 1Department of Pulmonary and Critical Care Medicine, Long Island Jewish Medical Center, New Hyde Park, New York 11040, USA.

Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America
|March 23, 2004
PubMed

Insights

Legionella micdadei pneumonia can cause severe, life-threatening diarrhea, a rare complication. Prompt treatment of this Legionella infection also led to the resolution of a pulmonary nodule.

Area of Science:

  • Infectious Diseases
  • Pulmonology
  • Gastroenterology

Background:

  • Legionella micdadei accounts for 60% of non-pneumophila Legionella infections.
  • Diarrhea is a common legionellosis symptom, but severe cases are infrequent.
  • Pulmonary nodules can occur with L. micdadei infections.

Observation:

  • A patient presented with profound secretory diarrhea (up to 8 L/day).
  • The diarrhea was secondary to culture-proven Legionella micdadei pneumonia.
  • A 3-cm pulmonary nodule was identified in the patient.

Findings:

  • Successful treatment of L. micdadei pneumonia resolved the severe diarrhea.
  • The pulmonary nodule completely disappeared following treatment for Legionella infection.
  • This case highlights a rare but severe gastrointestinal manifestation of L. micdadei.

Implications:

  • Clinicians should consider Legionella micdadei in patients with severe diarrhea and pneumonia.
  • Early diagnosis and treatment of L. micdadei infection are crucial for favorable outcomes.
  • The resolution of pulmonary nodules post-treatment supports L. micdadei as a cause.

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