An assessment of the value of midfinger smears in multibacillary leprosy patients

Abstract

In view of the different opinions on fingers as sites for persisting bacilli in multibacillary leprosy patients, it was decided to examine the midfingers for the presence of acid-fast bacilli (AFB) and establish its usefulness. Sixty-nine multibacillary leprosy patients, [lepromatous (LL) and borderline lepromatous (BL)] treated with multidrug therapy for fixed duration (2 years) were analysed. The bacillary load in the midfinger sites was lower when compared to that in the 'compulsory' (both earlobes) and 'optional' (four active lesions) sites. The midfinger bacterial index (BI) was higher among LL patients when compared to BL patients (p < 0.001). However, the difference in mean BI in 'optional' and 'compulsory sites' was not significant. The overall fall in BI was gradual and on expected lines for all sites, including midfingers, during treatment and follow-up period. Except in one case, at no time were the smears from midfinger sites positive when all other sites were negative, and their inclusion did not contribute to the early detection of relapse. Furthermore, the collection of blood-free smears from this site is technically difficult and often painful for the patient. The inclusion of midfinger smears in this study in patients in South India did not contribute useful information to that which is routinely available from smears of earlobes and other active sites.