Description

• Invasion of joints by microorganisms; often as part of a systemic infection/disease
• Curable type of arthritis
• System(s) affected: musculoskeletal
• Synonym(s): fungal arthritis; mycobacterial arthritis; subacute bacterial arthritis

Epidemiology

• 1–3% of patients with tuberculosis (TB) infections (1)
• 10–30% of extrapulmonary TB presents with musculoskeletal involvement.
• Predominant age: all ages
• Predominant gender
  • Male > female (Brucella and Mycobacterium)
  • Female > male (fungal)

Prevalence
1 in 3 million in the general population

Pediatric Considerations
Infrequent in pediatric population

Etiology and Pathophysiology

• Hematogenous invasion is most common.
• Contiguous spread
• Direct penetration via trauma
• Fungal infections may disseminate from primary pulmonary involvement, particularly in immunocompromised hosts.
• Direct contact with or consumption of infected animal products

Risk Factors

• HIV/AIDS
• Concurrent extra-articular infection
• Chronic inflammatory arthritis (e.g., rheumatoid arthritis [RA])
• Trauma, especially penetrating
• Prosthetic joint(s)
• Prior antibiotic, corticosteroid, or immunosuppressive therapy
• Serious chronic systemic illness (e.g., diabetes mellitus, liver disease, malignancy, primary immunodeficiency)
• Defective phagocytosis (e.g., chronic granulomatous disease)
• Injection drug use
• Exposure to specific infectious agents (e.g., brucellosis, unpasteurized milk, farmers, butchers, veterinarians)
• Gardening (sporotrichosis)
• Aquatic exposure (e.g., fish hook puncture and Mycobacterium marinum)

Commonly Associated Conditions

• Systemic infection
• Immunodeficiency/immunosuppression (e.g., from HIV/AIDS, lymphoma, transplantation, medications)
• Poncet disease (reactive arthritis associated with TB)