Unusual manifestations of histoplasmosis

George Richard Thompson1, Charles Edward LaValle, E Dale Everett

  • 1Department of Internal Medicine, Division of Infectious Diseases, University of Missouri, Columbia, Missouri, USA.

Insights

This study details six rare Histoplasma capsulatum infections, highlighting unusual presentations like meningitis and immune reconstitution syndrome. These findings expand understanding of this fungal infection's diverse clinical manifestations.

Area of Science:

  • Mycology
  • Infectious Diseases
  • Clinical Medicine

Background:

  • Histoplasma capsulatum is an endemic fungus causing histoplasmosis.
  • Typical histoplasmosis presentations are well-documented, but rare manifestations require further investigation.

Purpose of the Study:

  • To report and characterize uncommon clinical presentations of Histoplasma capsulatum infection.
  • To expand the understanding of the spectrum of histoplasmosis manifestations.

Main Methods:

  • Retrospective case series analysis.
  • Review of clinical data for six patients with Histoplasma capsulatum infection.
  • Detailed description of clinical findings, diagnostic methods, and treatment outcomes.

Main Results:

  • Six cases of Histoplasma capsulatum infection with unusual or previously unreported manifestations were identified.
  • Presentations included meningitis, immune reconstitution syndrome, relapsing pericarditis, and scleroconjunctivitis.
  • These cases demonstrate the diverse and sometimes unexpected ways H. capsulatum can affect various organ systems.

Conclusions:

  • Histoplasma capsulatum can present with a wider range of clinical manifestations than commonly recognized.
  • Clinicians should consider H. capsulatum in the differential diagnosis of unexplained meningitis, inflammatory syndromes, and ocular infections, especially in endemic areas.
  • Further research is needed to elucidate the mechanisms behind these rare presentations and optimize management strategies.

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