Detection of Mycobacterium avium-intracellulare in blood cultures of AID's patients can be done effectively using a combination of Isolator blood culture concentrate inoculated into Bactec mycobacterial radiometric vials. This combination of Isolator/Bactec is very sensitive but is both expensive and impractical. The present study is designed to determine the relative sensitivities of using 1) unconcentrated blood, 2) blood concentrated by conventional centrifugation, and 3) blood concentrated using an Isolator. The 3 types of inocula will be used to inoculate Bactec vials which will be monitored for growth as usual.
