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Histoplasmosis infection in patients with rheumatoid arthritis, 1998-2009

Timothy C Olson1, Tim Bongartz, Cynthia S Crowson

  • 1Department of Internal Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA.

BMC Infectious Diseases
|May 25, 2011
PubMed
Abstract

Insights

Rheumatoid arthritis patients on immunomodulatory drugs face a higher risk of histoplasmosis infections. Many cases were pulmonary and lacked typical symptoms, highlighting diagnostic challenges.

Area of Science:

  • Rheumatology
  • Infectious Diseases
  • Immunology

Background:

  • Patients with rheumatic diseases, such as rheumatoid arthritis (RA), have an elevated risk of infections.
  • This increased susceptibility is linked to both the underlying disease and its treatments.
  • Histoplasmosis is an uncommon infection reported in this patient population.

Purpose of the Study:

  • To investigate the characteristics of histoplasmosis infections in rheumatoid arthritis patients.
  • To analyze treatment outcomes and recurrence in RA patients with histoplasmosis.
  • To assess the clinical presentation of histoplasmosis in RA patients during the immunomodulatory therapy era.

Main Methods:

  • Retrospective medical record review of rheumatoid arthritis patients diagnosed with new histoplasmosis infections.
  • Study conducted at a single center (Mayo Clinic, Rochester, MN) between January 1, 1998, and January 30, 2009.
  • Inclusion criteria: diagnosis of RA, new histoplasmosis infection, and residency in an endemic region.

Main Results:

  • Twenty-six RA patients were diagnosed with histoplasmosis.
  • Most patients were on combination therapies, including anti-tumor necrosis factor (anti-TNF) agents, corticosteroids, and methotrexate.
  • The majority received prolonged treatment with itraconazole and/or amphotericin; two patients died from unrelated causes. One patient experienced recurrence after restarting anti-TNF therapy.

Conclusions:

  • This series represents the largest single-center cohort of RA patients with histoplasmosis in the era of immunomodulatory therapy.
  • Most affected patients had long-standing RA and were treated with multiple immunomodulatory agents.
  • Pulmonary histoplasmosis was most common, often presenting without typical signs and symptoms, posing diagnostic challenges.

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