Septic arthritis

Background

Microbiology

• Gonococcal: Neisseria gonorrhoeae, more common in young, sexually active adults
• Non-gonococcal bacterial:
  • Staphylococcus aureus, in immunocompetent and immunocompromised people as well as those at risk for Staphylococcus aureus bacteremia
  • Group B streptococci, more common in poorly-controlled diabetes
  • Streptococcus pneumoniae, more common in patients with hyposplenia
  • Enterobacteriaceae, especially if GI illness, or immunocompromised patients and those who inject drugs
  • Pseudomonas species, more common in diabetes, immunocompromised, trauma, or water exposures
  • Aeromonas species, more common after exposure to brackish water
  • Salmonella species, especially in patients with sickle cell disease or HIV
  • Eikenella corrodens and Peptostreptococcus species, especially if recent bite or other oral flora contamination
  • Pasteurella multocida, after cat bite
  • Capnocytophaga species, after dog bite
  • Mycoplasma hominis, with postpartum septic arthritis, recent genitourinary tract manipulation, and immunocompromise
• Other:
  • Mycobacterium tuberculosis and non-tuberculous mycobacteria (especially Mycobacterium chelonae and Mycobacterium fortuitum
  • Fungal infections including Candida species, Blastomyces dermatitidis, Cryptococcus species, Coccidioides immitis, and Sporothrix schenckii
  • Viral infections including HIV, hepatitis B virus, hepatitis C virus, parvovirus B19, and alphaviruses including chikungunya virus