Afb Isolation Rapid Culture Biopsy Tissue

Mycobacterium avium and Mycobacterium intracellulare, occur in patients with acquired immune deficiency syndrome (AIDS).7 In some institutions, the incidence of isolation of non-Mycobacterium tuberculosis species, specifically M avium complex, may exceed the rate of isolation of M tuberculosis. Mycobacteria have been recovered from culture of Kaposi sarcoma and bone marrow specimens, in which the characteristic granulomatous reaction has been absent.8,9 Optimal isolation of mycobacteria from tissue is accomplished by processing as much tissue as possible for culture. Swabs should not be submitted. Tuberculous spondylitis represents 50% to 60% of all cases of skeletal tuberculosis. It is seen in children in developing countries and adults older than 50 years of age in the United States and Europe. Frequently, several vertebrae are involved, and adjacent psoas muscle abscesses or paravertebral abscesses are not uncommon ("cold abscesses"). Colony counts obtained from bone biopsies are low; however, >90% are culture positive. The diagnosis of vertebral tuberculosis should be considered in all cases of unexplained spondylitis. Cases of sternal wound infection, early prosthetic valve endocarditis, infections complicating mammary augmentation surgery, and other cutaneous/subcutaneous infections have been attributed to rapidly growing mycobacteria.10,11M fortuitum is the most commonly implicated Mycobacterium in these infections, which are thought to be caused by local environmental strains rather than contaminated commercial surgical materials or devices. Rapidly growing mycobacteria often grow on routine bacterial culture media within the time allotted to incubating routine bacterial cultures. Such organisms may be misidentified as "diphtheroids" and disregarded as contaminants.