How helpful are synovial fluid analyses and cultures in a fungal septic arthritis?
As in TB, cell counts are highly variable. Typically, white blood cell counts range from 10,000 to 60,000/mm 3 with either polymorphonuclear or mononuclear cells predominating.
Culture of synovial fluid is critically important in establishing the diagnosis, but the colony counts are often low. Laboratory personnel must be alerted to the possibility of fungal disease so that they do not use inhibitory media.
Recently, polymerase chain reaction-based amplification techniques have been developed for many species of mycobacteria and fungi that may be useful diagnostic techniques in the future.