Classification of leprosy cases under field conditions in Bangladesh. I. Usefulness of skin-smear examinations

Abstract

Summary In 2 non-governmental organization projects in Bangladesh 244 new leprosy patients were classified in the field according to clinical criteria. Skin smears were taken at 4 standardized sites and at the most active peripheral lesion, where a biopsy was also taken.Comparison of the clinical field classification with the results of the skin smears and biopsies gives a sensitivity of 92· 1 % for the clinical criteria, but a specificity of only 41'3%. The skin-smear results, on the other hand, have a sensitivity of 88-4% and a specificity of 98·1 %.Thus, skin smears may contribute considerably to the operational classifica tion of leprosy patients under field conditions. Quality control of the peripheral laboratory is essential. Appropriate site selection for the smear taking will also contribute to increased performance. Analysis of the skin-smear results suggests that the policy of taking smears at standardized sites should be abandoned in favour of the earlobes and active peripheral lesions.According to WHO recommendations, 1 the operational classification of leprosy cases in paucibacillary (PB) and multi bacillary (MB) patients should be based on the bacter iological index, whereby the presence of acid-fast bacilli (AFB) at any single site is the criterion used fo r classification as MB. However, the validity of skin smear results has often been questioned, 2 -4 and many leprosy control programmes base their operational

Comparing the Clinical and Histological Diagnosis of Leprosy and Leprosy Reactions in the INFIR Cohort of Indian Patients with Multibacillary Leprosy

“…Most of the misdiagnoses relating to LL disease were in the BL group and differentiating between these two types is not always straightforward. Groenen et al [19] found that adding in a category of diffuse infiltration and nodules improved the diagnosis of LL cases in the MB leprosy classification by ensuring that diffuse infiltration is not overlooked.…”

Alocação do paciente hanseniano na poliquimioterapia: correlação da classificação baseada no número de lesões cutâneas com os exames baciloscópicos

“…14 A necessidade do exame baciloscópico para a classificação dos casos de hanseníase no campo foi avaliada em um estudo na Índia, onde os resultados demonstraram especificidade de 98,1% com a classificação baciloscópica e de 41,3% com a baseada em critérios clínicos. 15 No Brasil, Andrade e colaboradores realizaram um trabalho comparando diferentes classificações utilizadas pelas coordenações dos programas de controle em diferentes unidades da federação. Segundo esses autores, se a baciloscopia fosse o único However, although technically relatively simple and of easy accomplishment in operational terms, in most of the leprosy control programs, there were difficulties related to the implementation of the bacilloscopic exams, because they either resulted in low quality (low reproducibility or reliability), or because of the nonexistence of these exams in the public health services.…”

Methods for the Classification of Leprosy for Treatment Purposes

“…Oskam [8] reviewed previous studies [9][10][11][12][13][14], mostly prior to 1993, that compared the number of skin lesions (although not always with 15 as the cutoff) and body zones involved with skin smears or biopsies with a BI value 10-1 (table 4). The first 3 studies resulted in a low specificity (39%-42%) for a clinical diagnosis of MB leprosy in locations where MB leprosy is more common [9][10][11] but not in areas where it is less common (81%-88%) [12,13]. Misclassifying patients with PB leprosy as having MB leprosy may result in overtreatment, whereas misclassifying patients with MB leprosy as having PB leprosy may result in undertreatment.…”