Evaluation of qPCR-Based Assays for Leprosy Diagnosis Directly in Clinical Specimens

The increased reliability and efficiency of the quantitative polymerase chain reaction (qPCR) makes it a promising tool for performing large-scale screening for infectious disease among high-risk individuals. To date, no study has evaluated the specificity and sensitivity of different qPCR assays for leprosy diagnosis using a range of clinical samples that could bias molecular results such as difficult-to-diagnose cases. In this study, qPCR assays amplifying different M. leprae gene targets, sodA, 16S rRNA, RLEP and Ag 85B were compared for leprosy differential diagnosis. qPCR assays were performed on frozen skin biopsy samples from a total of 62 patients: 21 untreated multibacillary (MB), 26 untreated paucibacillary (PB) leprosy patients, as well as 10 patients suffering from other dermatological diseases and 5 healthy donors. To develop standardized protocols and to overcome the bias resulted from using chromosome count cutoffs arbitrarily defined for different assays, decision tree classifiers were used to estimate optimum cutoffs and to evaluate the assays. As a result, we found a decreasing sensitivity for Ag 85B (66.1%), 16S rRNA (62.9%), and sodA (59.7%) optimized assay classifiers, but with similar maximum specificity for leprosy diagnosis. Conversely, the RLEP assay showed to be the most sensitive (87.1%). Moreover, RLEP assay was positive for 3 samples of patients originally not diagnosed as having leprosy, but these patients developed leprosy 5–10 years after the collection of the biopsy. In addition, 4 other samples of patients clinically classified as non-leprosy presented detectable chromosome counts in their samples by the RLEP assay suggesting that those patients either had leprosy that was misdiagnosed or a subclinical state of leprosy. Overall, these results are encouraging and suggest that RLEP assay could be useful as a sensitive diagnostic test to detect M. leprae infection before major clinical manifestations

Integrative literature review of the reported uses of serological tests in leprosy management

Abstract: An integrative literature review was conducted to synthesize available publications regarding the potential use of serological tests in leprosy programs. We searched the databases Literatura Latino-Americana e do Caribe em Ciências da Saúde, Índice Bibliográfico Espanhol em Ciências da Saúde, Acervo da Biblioteca da Organização Pan-Americana da Saúde, Medical Literature Analysis and Retrieval System Online, Hanseníase, National Library of Medicine, Scopus, Ovid, Cinahl, and Web of Science for articles investigating the use of serological tests for antibodies against phenolic glycolipid-I (PGL-I), ML0405, ML2331, leprosy IDRI diagnostic-1 (LID-1), and natural disaccharide octyl-leprosy IDRI diagnostic-1 (NDO-LID). From an initial pool of 3.514 articles, 40 full-length articles fulfilled our inclusion criteria. Based on these papers, we concluded that these antibodies can be used to assist in diagnosing leprosy, detecting neuritis, monitoring therapeutic efficacy, and monitoring household contacts or at-risk populations in leprosy-endemic areas. Thus, available data suggest that serological tests could contribute substantially to leprosy management

Epidermal Permeability Barrier in the Treatment of Keratosis Pilaris

Objectives. To evaluate and compare the efficacy, safety, hydrating properties, and tolerability of 10% lactic acid (LA) and 5% salicylic acid (SA) in the therapy of keratosis pilaris (KP). Material and Method. Patients with KP were randomized for treatment with either 10% LA or 5% SA creams being applied twice daily for 3 months. The patients were clinically assessed at baseline and after 4, 8, and 12 weeks of treatment and 4 weeks after treatment. The functional properties of the stratum corneum (SC) were determined before treatment, 12 weeks, and follow-up phase by high-frequency conductance and transepidermal water loss (TEWL). Results. At the end of the trial, the mean reduction of the lesions from baseline was statistically significant for 10% LA (66%) and 5% SA (52%). During the treatment, higher conductance values were found on both group and this improvement was maintained until the follow up period. No significant differences in transepidermal water loss were observed after treatment. The adverse effects were limited to mild irritation localized on the skin without systemic side effect. Conclusion. The study demonstrated that 10% LA and 5% SA are beneficial to treat KP with the significantly clearance and marked improvement as by instrumental evaluation

DNA amplification for detection of leprosy and assessment of efficacy of leprosy chemotherapy

Polymerase chain reaction (PCR) for the detection of Mycobacterium leprae was applied to fresh skin biopsies and slit-skin smears from 122 untreated leprosy patients. The PCR positivity rates in biopsies were 95.6% in multibacillary (MB) cases and 44.2% in paucibacillary (PB) cases. Following 1 month of treatment, MB cases declined by 54.3% and PB cases by 61.8% of initial values. Six-month values also declined from initial positivity rates to 50.3% and 53.8% of initial values in MB and PB, respectively. Larger declines in the rate of positivity were seen for skin-smear samples at 1 and 6 months in both MB and PB, but overall PCR positivity rates were lower than biopsy rates for M. lepra

Unilateral Linear Punctate Palmoplantar Keratoderma: A Case Report

Punctate palmoplantar keratoderma (PPPK) is a rare entity with an estimated prevalence rate of 1.17/100,000. PPPK usually presents with bilateral asymptomatic, tiny, hyperkeratotic punctate papules and plaques on the palmoplantar surface. Among the PPPK varieties, the linear presentation is much rarer, and so far there have been only 3 case reports. Here, we report the case of a 27-year-old female Thai patient who presented to our outpatient clinic with unilateral asymptomatic linear thickening lesions on her right sole since childhood. There were no similar lesions on other parts of the body. A histopathologic examination revealed epidermal hyperplasia and hyperkeratosis without columns of parakeratosis or cornoid lamella. The other examinations were normal. The clinical and histological contexts were consistent with a diagnosis of unilateral linear PPPK. The patient was treated with topical 10% urea cream and 10% salicylic acid cream twice daily. To the best of our knowledge, this is the first reported case of unilateral linear PPPK in Thailand, and the fourth reported case worldwide