Clinicopathological correlation in diagnosis of Hansen's disease: A histopathologist's perspective

Abstract

Reshma Gopal Kini, Hemangini Choudhury

Objectives: Hansen’s disease follows a chronic course and though curable causes considerable degree of disability and deformity. Key to managing leprosy is its early diagnosis and treatment with multidrug regimen. Histopathological evaluation of skin biopsies plays crucial role in the correct diagnosis of clinically ambiguous cases. Moreover, classifying lesions by the Ridley-Jopling (RJ) system gives personalized information about the immunological status of the individual and also aids in placing the patient in the correct treatment category. Materials and Methods: Skin biopsies obtained from newly diagnosed cases of leprosy were included. Paraffin-embedded sections stained with hematoxylin-eosin and Fite-Faraco were evaluated for features confirming leprosy and further categorized as per the RJ system. Sensitivity, specificity, and concordance rates were studied. Results: A total of 93 cases were studied after excluding those which had a component of reaction. Among the clinically suspected cases, 93% of the biopsies were positive for leprosy. Sensitivity of clinical diagnosis ranged from 60% for borderline (BB) to 100% for histoid leprosy. Specificity ranged from 84.5% for borderline tuberculoid (BT) to 100% for neuritic leprosy. The agreement between histopathological and clinical diagnosis was more than 90% in all the subclasses except for BT which showed agreement in about 82% of the cases. Two of the cases were categorized into multibacillary type of leprosy-based histopathological evaluation. Conclusion: Confirmation of leprosy by the examination of skin biopsy before starting the patient on long-term multidrug therapy is invaluable. Experience of the leprologists and adherence to histopathological criteria as per the RJ classification yield excellent concordance rates.