Diagnosis of tuberculosis and other diseases caused by mycobacteria.

The adequate diagnosis and treatment of tuberculosis depends on many events, including rapid pathogen detection, patient isolation, species identification, and drug susceptibility testing. Well trained staff, using state-of-the-art technology, are necessary in the mycobacteriology laboratory to produce timely results that are necessary for the patients' care and public health measures. Mycobacteriology laboratories still play a pivotal role in the control of tuberculosis, which is especially true in view of the spread of multidrug-resistant tuberculosis. One way to optimize diagnostic efforts in spite of limited financial resources might be to sort and allocate specimens according to a system of priorities, e.g., diagnostic versus follow-up specimens. A "fast track" program for tuberculosis testing, which should be established as part of a dynamic diagnostic network, should focus on the highly infectious patient population. Collaboration between clinicians and mycobacteriologists remains the basis of dynamic diagnostic teamwork. Immediate screening of smears for acid-fast-bacilli in patients suspected of tuberculosis, followed by immediate processing of smear-positive specimens using modern mycobacteriological technology, should be given high priority. Diagnosis of disease due to nontuberculous mycobacteria can be difficult. Nontuberculous mycobacteria are commonly found in nature, and assessment as to whether a nontuberculous mycobacterium isolate is clinically significant can be a difficult task.