Assume if no other information is available – S aureus

Sexually active – Neisseria gonorrhoeae (rare), septic arthritis more common

Sickle cell disease – Salmonella and S aureus

Prosthetic joint replacement – S aureus and S epidermidis

Vertebral involvement – S aureus, Mycobacterium tuberculosis (Pott disease)

Cat and dog bite – Pasteurella multocida

IV drug abuse – S aureus; also Pseudomonas, Candida

Elevated CRP and ESR common but nonspecific.Radiographs are insensitive early but can be useful in chronic osteomyelitis. MRI is best for detecting acute infection and detailing anatomic involvement.