Septic Bursitis
Last updated: October 31, 2014
ICD9 Code: Bursitis NOS 727.3; Prepatellar septic bursitis 726.65; olecranon septic bursitis 726.33
ICD10 Code: other Bursitis, unspecified M71.50; Prepatellar bursitis, unspecified M70.40; olecranon bursitis, unspecified M70.20
Definition: Septic bursitis is a bacterial infection of the bursal space, most commonly involving the olecranon and prepatellar areas.
Etiology: Most cases are caused by inoculation of skin flora into the bursal space by local trauma. Some occupations (e.g., carpet laying, roofing) may be predisposed to inflammatory or septic bursitis.
Pathology: Changes of acute and chronic inflammation in the bursa and adjacent tissues.
Demographics: Most series have a predominance of males, possibly because of occupational hazards. Normal individuals without underlying comorbid conditions can be affected.
Cardinal Findings: The classic presentation is an acute, painful, warm swelling in the periarticular region. Because the joint is not involved, range of motion is usually unaffected. Fever is usually not present.
Diagnostic Tests: Because of the focal acute inflammatory presentation, bursal aspiration should be performed with a large-bore needle (18 or 19 gauge). Cultures of bursal fluid are diagnostic. The bursal fluid WBC can be variable and does not correlate well with the severity of infection. Even relatively low WBC values can be seen with active bacterial infection; thus, cultures are important in all suspected cases. Bursal fluid is more superficial than synovial fluid; care should be taken to avoid the joint space.
Keys to Diagnosis: Acute onset of periarticular swelling should raise suspicion. Septic arthritis can be diagnosed by bursal aspiration and cultures.
Differential Diagnosis: Septic arthritis should be considered if there are fever and limited range of motion or if pain limits motion. Acute bursitis can be seen with gout and RA. Cellulitis or tendinitis may mimic bursitis with pain and erythematous skin changes.
Therapy: Antibiotics should be started soon after the initial bursal aspiration. Oral antibiotics are usually adequate. Although culture results are pending (usually 24–48 hours), the initial antibiotic should provide coverage for S. aureus until culture results can further guide therapy. Surgical drainage or bursal removal is rarely required.
Prognosis: Most patients recover completely without sequelae.
BIBLIOGRAPHY
Ho G, Su EY. Antibiotic therapy of septic bursitis: its implication in the treatment of septic arthritis. ArthritisRheum 1981;24:905–911.PMID:7259803
Pien FD, Ching D, Kim E. Septic bursitis: experience in a community practice. Orthopedics 1991;14:981–984.PMID:1946062