AMPLIFICATION REACTIONS IN MYCOBACTERIOLOGY

Tuberculosis control programmes are faced with an increased burden of cases, a shift towards diagnostically more difficult categories of pat ients such as extrapulmonary and smear-negative cases, and the emergen ce of multidrug-resistant strains of M. tuberculosis. Improved diagnos is would be a valuable contribution in the struggle to solve this glob al public health emergency. Nucleic acid amplification reactions promi se to reduce the time for diagnosis from weeks to hours, while surpass ing the sensitivity and specificity of the classical methods. Besides their potential value in diagnosis, amplification reactions offer the possibility of a rapid identification and drug susceptibility determin ation. Their application in other fields, such as epidemiology, could benefit the control of mycobacteriosis indirectly. Although critical a ssessment is warranted, several features, such as the availibility of standardized kits, strongly justify the evaluation of amplification re actions for the detection of mycobacteria for use in the clinical labo ratory. In fact, evaluation of the technology now, at its present leve l of development, even in an endemic setting in a developing country, would yield useful recommendations towards its improvement for applica tion in different settings, in terms of efficiency, simplicity and cos t.