An Extraordinary Case of Prosthetic Joint Infection by Listeria monocytogenes and Histoplasma capsulatum

Area of Science:

• Infectious Diseases
• Microbiology
• Orthopedic Surgery

Background:

• Prosthetic joint infections (PJIs) are significant complications following hip and knee arthroplasty.
• Gram-positive bacteria are the most frequent cause of PJIs, with fungal and atypical bacterial infections being less common.

Observation:

• A case of late PJI in an immunocompromised patient with a history of right knee arthroplasty is presented.
• Synovial fluid cultures identified a co-infection with *Listeria monocytogenes* and *Histoplasma capsulatum*.

Findings:

• This co-infection represents an extraordinary and unique etiology for prosthetic joint infections.
• Both *Listeria monocytogenes* and *Histoplasma capsulatum* have the capacity to form biofilms, complicating treatment.
• A two-stage exchange surgery combined with antimicrobial therapy is the recommended treatment approach.

Implications:

• Clinicians must maintain vigilance for unusual pathogens in PJI cases, especially in immunocompromised individuals.
• The presence of specific risk factors and host conditions should prompt consideration of less common etiologies.
• Effective management requires a thorough understanding of the pathogens involved and their biofilm-forming capabilities.