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Rat bite fever as a presenting illness in a patient with AIDS

R Chean1, D A Stefanski, I J Woolley

  • 1Department of Infectious Diseases, Monash Medical Centre, 246 Clayton Rd., Clayton, VIC, 3168, Australia. royale168@hotmail.com

Infection
|August 31, 2011
PubMed

Insights

This study reports the first case of septic arthritis caused by rat bite fever in a patient with newly diagnosed human immunodeficiency virus (HIV). Molecular methods confirmed the rare bacterial infection, highlighting their importance in diagnosing culture-negative cases.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Molecular Diagnostics

Background:

  • Septic arthritis in human immunodeficiency virus (HIV)-infected individuals often presents diagnostic challenges due to culture-negative results.
  • The etiology of culture-negative septic arthritis in this population remains poorly understood.
  • Advancements in molecular techniques offer potential solutions for identifying pathogens in sterile site infections.

Observation:

  • A case of septic arthritis was observed in a patient recently diagnosed with HIV.
  • The patient presented with symptoms suggestive of septic arthritis, but initial cultures were negative.
  • The infection was ultimately attributed to Streptobacillus moniliformis, the causative agent of rat bite fever.

Findings:

  • 16S rRNA sequence analysis definitively identified Streptobacillus moniliformis as the pathogen responsible for the septic arthritis.
  • This represents the first documented instance of septic arthritis caused by this bacterium in a patient with HIV.
  • Molecular confirmation was crucial in establishing the diagnosis due to the failure of traditional culture methods.

Implications:

  • This case underscores the utility of molecular diagnostic methods, such as 16S rRNA sequencing, in identifying fastidious or unculturable organisms in culture-negative infections.
  • It expands the known spectrum of infectious agents associated with septic arthritis in HIV-positive individuals.
  • Further research into the role of rat bite fever in HIV-associated joint infections may be warranted.

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