Can bursae become infected?
The olecranon (adults) and prepatellar (children) bursae are the most common sites of septic bursitis. Most septic bursitis occurs in patients who repeatedly traumatize the skin in these areas (carpenters, laborers). Alcoholism, diabetes, and preexisting bursal disease are also risk factors. More than 50% also have a surrounding cellulitis and a few patients may get a noninflammatory sympathetic joint effusion of the underlying joint. Over 80% of septic bursitis is due to S. aureus . Blood cultures are rarely positive because the organisms get into the bursa by transcutaneous spread through skin abrasions. Patients usually have abrupt onset of pain, swelling, and erythema. Diagnosis is made by aspiration, Gram stain, and culture of bursal fluid. Bursal fluid cell counts are elevated but not as much as in septic joints. Antibiotics should be administered IV initially and the bursa aspirated repeatedly or incised and drained. This is especially important for febrile patients or those who are immunocompromised. After control of the infection, oral antibiotics are taken for an additional 2 to 3 weeks. Failure to respond is an indication for bursectomy.
