Cell counts of bursal fluid provide a simple test for septic bursitis

Cell counts of bursal fluid provide a simple test for septic bursitis

Tests for distinguishing septic from non-spetic bursitis of the olecranon and prepatellar bursae are not widely availableor are poorly sensitive. On p 1877 Stell and Gransden comparedtwo easily performed tests in 36 patients: estimation of cellcounts in bursal fluid and inoculation of the fluid into liquidmedia. The definitive diagnosis was determined by a panel of cliniciansusing all clinical, laboratory, and follow up data. Culture onliquid media gave positive results in all 17 cases of septic bursitis:sensitivity 100%, specificity 89%, positive predictive value 89%.Median white cell counts were also higher in septic cases: sensitivity94%, specificity 79%, positive predictive value 80%. Culture inliquid media was more sensitive than direct culture. The authorssay that guidance on diagnosis can be obtained rapidly by a cellcount and treatment started the same day; if doubt remains thenantibiotics can be given while awaiting the results of culture.