BACKGROUND: the World Health Organization (WHO) and the Brazilian Health Ministry recommend the adoption of the operational classification for therapeutic purposes (multi- or paucibacillary). The validity of that classification is discussed taking as a reference the results of bacilloscopic exams. OBJECTIVE: To verify the sensitivity and specificity of the operational clinical classification that takes into account exclusively the number of cutaneous lesions and that which considers the thickening of neural trunks as well as the number of cutaneous lesions, and relating these with the results from the bacilloscopic exam. METHODS: The information source was consultation of the records referring to patients with a diagnosis of leprosy, from January 2000 to March 2001, at the Fundação Alfredo de Matta, in Manaus, AM. The demographic, clinical and laboratorial data were compiled. RESULTS: The clinical classification based exclusively on the number of cutaneous lesions showed a sensitivity of 73.6% and specificity of 85.6% regarding the bacilloscopy. The classification that combines the number of cutaneous lesions and neural thickening demonstrated 75.8% sensitivity and 71.8% specificity. CONCLUSION: The clinical classification of leprosy based on the number of cutaneous lesions showed, in this work, sensitivity and specificity values similar to those described in studies done in other countries. When the classification was broadened to include the other clinical parameter (the presence of thickened peripheral nerves) there was a significant decrease in the specificity, without a statistically significant increase in sensitivity.
leprosy; leprosy; sensitivity; specificity
