Classification of leprosy
Leprosy can be classified on the basis of clinical manifestations and skin smear results. In the classification based on skin smears, patients showing negative smears at all sites are grouped as paucibacillary leprosy (PB), while those showing positive smears at any site are grouped as having multibacillary leprosy (MB).
However, in practice, most programmes use clinical criteria for classifying and deciding the appropriate treatment regimen for individual patients, particularly in view of the non-availability or non-dependability of the skin-smear services. The clinical system of classification for the purpose of treatment includes the use of number of skin lesions and nerves involved as the basis for grouping leprosy patients into multibacillary (MB) and paucibacillary (PB) leprosy.
While classifying leprosy, it is particularly important to ensure that patients with multibacillary disease are not treated with the regimen for the paucibacillary form of the disease.