[Encephalitis without pneumonia caused by Legionella bozemanii]

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Tractable Mammalian Cell Infections with Protozoan-primed Bacteria
13:54

Tractable Mammalian Cell Infections with Protozoan-primed Bacteria

Published on: April 2, 2013

I Potasman1, A Liberson, M Schwartz

  • 1Dept. of Neurology, Haifa City Medical Center, Technion Faculty of Medicine.

Harefuah
|February 15, 1990
PubMed

Insights

Legionnaire disease (LD) can mimic viral encephalitis, even without pneumonia. Early diagnosis is key, as patients can recover fully.

Area of Science:

  • Infectious Diseases
  • Neurology
  • Clinical Medicine

Background:

  • Legionnaire disease (LD) typically presents as pneumonia with systemic symptoms.
  • Neurologic manifestations in LD usually occur with or after fever onset.
  • Pneumonia-preceding neurological symptoms are rare in LD.

Observation:

  • Three patients with LD presented with severe viral encephalitis symptoms but no pneumonia.
  • High serum IgG and IgM antibody titers against Legionella species were observed.
  • Cerebrospinal fluid analysis showed a positive reaction only against L. bozemanii.

Findings:

  • Legionella bozemanii infection can manifest as encephalitis without concurrent pneumonia.
  • LD should be considered in the differential diagnosis of severe viral encephalitis.
  • Prompt diagnosis and treatment led to full recovery without sequelae in these cases.

Implications:

  • Broadens the differential diagnosis for encephalitis presentations.
  • Highlights the importance of considering atypical infectious causes for neurological syndromes.
  • Suggests specific serological and CSF testing for Legionella in encephalitis cases.

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