Benefits and limitations of fine needle aspiration cytology in the diagnosis and classification of leprosy in primary and secondary healthcare settings.

Abstract

The goal of the World Health Organization (WHO) is to eliminate leprosy as a public health problem. This will only be possible when all patients are detected and cured using multidrug therapy, which requires accurate diagnosis prior to treatment. The objective of this study was to evaluate the possibility of the diagnosis of leprosy lesions by fine needle aspiration cytology according to a modification of the Ridley-Jopling scale, as it can be used in primary and secondary healthcare centres, especially in low-resource settings in which leprosy is prevalent. A prospective study comprising 54 cases with cardinal features of leprosy was performed. Among the 54 cases, 27 patients consented to a histopathological biopsy procedure. The slides were stained with Giemsa, modified Ziehl-Neelsen, Papanicolaou and haematoxylin and eosin methods. Among the 54 cases, 34 were reported as tuberculoid leprosy, five as mid-borderline (BB), three as borderline lepromatous (BL) and eight as lepromatous leprosy (LL); four were unsatisfactory. Histopathological study was performed in 27 cases, which showed cyto-histological correlation in 21 cases (78%). Agreement between histological and cytological diagnosis was achieved in 12 of the 15 tuberculoid cases, one of the three BB cases, one of the two BL cases and all seven LL cases. With the implementation of the WHO classification based on patch counting, there is the possibility of the over-treatment of paucibacillary cases and under-treatment of multibacillary cases. Cytology in terms of cellular type morphology and bacteriological study can complement the WHO classification.