A Macrophage Response to Mycobacterium leprae Phenolic Glycolipid Initiates Nerve Damage in Leprosy.

Mycobacterium leprae causes leprosy and is unique among mycobacterial diseases in producing peripheral neuropathy. This debilitating morbidity is attributed to axon demyelination resulting from direct interaction of the M. leprae-specific phenolic glycolipid 1 (PGL-1) with myelinating glia and their subsequent infection. Here, we use transparent zebrafish larvae to visualize the earliest events of M. leprae-induced nerve damage. We find that demyelination and axonal damage are not directly initiated by M. leprae but by infected macrophages that patrol axons; demyelination occurs in areas of intimate contact. PGL-1 confers this neurotoxic response on macrophages: macrophages infected with M. marinum-expressing PGL-1 also damage axons. PGL-1 induces nitric oxide synthase in infected macrophages, and the resultant increase in reactive nitrogen species damages axons by injuring their mitochondria and inducing demyelination. Our findings implicate the response of innate macrophages to M. leprae PGL-1 in initiating nerve damage in leprosy.

Second-Strand Synthesis-Based Massively Parallel scRNA-Seq Reveals Cellular States and Molecular Features of Human Inflammatory Skin Pathologies.

High-throughput single-cell RNA-sequencing (scRNA-seq) methodologies enable characterization of complex biological samples by increasing the number of cells that can be profiled contemporaneously. Nevertheless, these approaches recover less information per cell than low-throughput strategies. To accurately report the expression of key phenotypic features of cells, scRNA-seq platforms are needed that are both high fidelity and high throughput. To address this need, we created Seq-Well S3 ("Second-Strand Synthesis"), a massively parallel scRNA-seq protocol that uses a randomly primed second-strand synthesis to recover complementary DNA (cDNA) molecules that were successfully reverse transcribed but to which a second oligonucleotide handle, necessary for subsequent whole transcriptome amplification, was not appended due to inefficient template switching. Seq-Well S3 increased the efficiency of transcript capture and gene detection compared with that of previous iterations by up to 10- and 5-fold, respectively. We used Seq-Well S3 to chart the transcriptional landscape of five human inflammatory skin diseases, thus providing a resource for the further study of human skin inflammation.

In search of biomarkers for leprosy by unraveling the host immune response to Mycobacterium leprae.

Mycobacterium leprae, the causative agent of leprosy, is still actively transmitted in endemic areas reflected by the fairly stable number of new cases detected each year. Recognizing the signs and symptoms of leprosy is challenging, especially at an early stage. Improved diagnostic tools, based on sensitive and specific biomarkers, that facilitate diagnosis of leprosy are therefore urgently needed. In this review, we address the challenges that leprosy biomarker research is facing by reviewing cell types reported to be involved in host immunity to M leprae. These cell types can be associated with different possible fates of M leprae infection being either protective immunity, or pathogenic immune responses inducing nerve damage. Unraveling these responses will facilitate the search for biomarkers. Implications for further studies to disentangle the complex interplay between host responses that lead to leprosy disease are discussed, providing leads for the identification of new biomarkers to improve leprosy diagnostics.

Reduction of host cell mitochondrial activity as Mycobacterium leprae's strategy to evade host innate immunity.

Leprosy is a much-feared incapacitating infectious disease caused by Mycobacterium leprae or M lepromatosis, annually affecting roughly 200,000 people worldwide. During host-pathogen interaction, M leprae subverts the immune response, leading to development of disease. Throughout the last few decades, the impact of energy metabolism on the control of intracellular pathogens and leukocytic differentiation has become more evident. Mitochondria play a key role in regulating newly-discovered immune signaling pathways by controlling redox metabolism and the flow of energy besides activating inflammasome, xenophagy, and apoptosis. Likewise, this organelle, whose origin is probably an alphaproteobacterium, directly controls the intracellular pathogens attempting to invade its niche, a feature conquered at the expense of billions of years of coevolution. In the present review, we discuss the role of reduced host cell mitochondrial activity during M leprae infection and the consequential fates of M leprae and host innate immunity. Conceivably, inhibition of mitochondrial energy metabolism emerges as an overlooked and novel mechanism developed by M leprae to evade xenophagy and the host immune response.

High-Resolution Plasma Metabolomics Identifies Alterations in Fatty Acid, Energy, and Micronutrient Metabolism in Adults Across the Leprosy Spectrum.

BACKGROUND: High-resolution metabolomics (HRM) is an innovative tool to study challenging infectious diseases like leprosy, where the pathogen cannot be grown with standard methods. Here, we use HRM to better understand associations between disease manifestations, nutrition, and host metabolism. METHODS: From 2018 to 2019, adults with leprosy and controls were recruited in Minas Gerais, Brazil. Plasma metabolites were detected using an established HRM workflow and characterized by accurate mass, mass to charge ratio m/z and retention time. The mummichog informatics package compared metabolic pathways between cases and controls and between multibacillary (MB) and paucibacillary (PB) leprosy. Additionally, select individual metabolites were quantified and compared. RESULTS: Thirty-nine cases (62% MB and 38% PB) and 25 controls were enrolled. We found differences (P < .05) in several metabolic pathways, including fatty acid metabolism, carnitine shuttle, retinol, vitamin D3, and C-21 steroid metabolism, between cases and controls with lower retinol and associated metabolites in cases. Between MB and PB, leukotrienes, prostaglandins, tryptophan, and cortisol were all found to be lower in MB (P < .05). DISCUSSION: Metabolites associated with several nutrient-related metabolic pathways appeared differentially regulated in leprosy, especially MB versus PB. This pilot study demonstrates the metabolic interdependency of these pathways, which may play a role in the pathophysiology of disease.

Macrophage immunophenotypes in Jorge Lobo's disease and lepromatous leprosy- A comparative study.

Jorge Lobo's disease (JLD) and lepromatous leprosy (LL) share several clinical, histological and immunological features, especially a deficiency in the cellular immune response. Macrophages participate in innate and adaptive inflammatory immune responses, as well as in tissue regeneration and repair. Macrophage function deficiency results in maintenance of diseases. M1 macrophages produce pro-inflammatory mediators and M2 produce anti-inflammatory cytokines. To better understand JLD and LL pathogenesis, we studied the immunophenotype profile of macrophage subtypes in 52 JLD skin lesions, in comparison with 16 LL samples, using a panmacrophage (CD68) antibody and selective immunohistochemical markers for M1 (iNOS) and M2 (CD163, CD204) responses, HAM56 (resident/fixed macrophage) and MAC 387 (recently infiltrating macrophage) antibodies. We found no differences between the groups regarding the density of the CD163, CD204, MAC387+ immunostained cells, including iNOS, considered a M1 marker. But HAM56+ cell density was higher in LL samples. By comparing the M2 and M1 immunomarkers in each disease separately, some other differences were found. Our results reinforce a higher M2 response in JLD and LL patients, depicting predominant production of anti-inflammatory cytokines, but also some distinction in degree of macrophage activation. Significant amounts of iNOS + macrophages take part in the immune milieu of both LL and JLD samples, displaying impaired microbicidal activity, like alternatively activated M2 cells.

Nail fold capillaroscopy in leprosy: Unveiling the microvascular changes.

BACKGROUND: Leprosy, a chronic infectious disease, is associated with various nail changes. Its etiopathogenesis is multifaceted, with microvascular damage being crucial. Nail fold capillaroscopy (NFC) emerges as a novel tool for detecting early vascular deficits in leprosy. The study aimed to assess and provide a complete clinical characterization of NFC changes in leprosy patients. METHODS: It is an observational cross-sectional study, done over a period of 1.5 year (January 2021 to august 2022) in a tertiary care hospital, encompassing 60 patients diagnosed with leprosy (18-60 years). After obtaining informed consent; detailed history, complete cutaneous and neurological examinations were conducted. All fingernails and toenails were examined for clinical changes. Subsequently, onychoscopy was performed using USB type of video-dermatoscope (Model AM7115MZT Dino-lite), a non-invasive tool. This was followed by NFC which was done for all fingernails and images were recorded by single operator, which were then assessed for quantitative and qualitive changes and statistical analysis was conducted using SPSS v20, with mean capillary density compared using Student's t-test, morphological change frequencies assessed by proportions, and group comparisons made using Chi-square or Fischer exact tests, with a significance threshold of p < 0.05. RESULTS: Among the 60 patients, 39 were in the lepromatous group, which included both borderline lepromatous (BL) and lepromatous leprosy (LL) patients, and 17 were in the tuberculoid group, which included borderline tuberculoid (BT) leprosy patients; 23.3 % had Type 1 reactions, and 18.3 % had Type 2 reactions. Nail fold capillaroscopy (NFC) showed microvasculature changes in 93.3 % of patients. The average capillary density was 6.8 ± 1.5 capillaries per mm, with the lepromatous group having a lower density (6.5 ± 1.09) compared to the tuberculoid group (7.0 ± 0.86). The most common NFC changes in the tuberculoid group were tortuous capillaries (70 %), capillary dropouts, and dilated capillaries (both 64.7 %). In the lepromatous group, capillary dropouts (82 %) were most frequent, followed by tortuous (69 %), receding (69 %), and dilated capillaries (66 %). A dilated and prominent subpapillary plexus was more common in the lepromatous group (35 %, p = 0.04). Patients with trophic changes in the lepromatous group had more capillary dropouts and bizarre capillaries. Capillary dropouts, dilated capillaries, and visible subpapillary venous plexus were more prevalent in patients with Type 2 reactions. CONCLUSION: NFC changes are prevalent in both tuberculoid and lepromatous leprosy, which may be an indicator of peripheral vascular compromise and trophic changes, especially in lepromatous leprosy. NFC can be an auxiliary tool for detecting microvascular abnormalities in leprosy patients.

Whole mitogenome sequencing uncovers a relation between mitochondrial heteroplasmy and leprosy severity.

BACKGROUND: In recent years, the mitochondria/immune system interaction has been proposed, so that variants of mitochondrial genome and levels of heteroplasmy might deregulate important metabolic processes in fighting infections, such as leprosy. METHODS: We sequenced the whole mitochondrial genome to investigate variants and heteroplasmy levels, considering patients with different clinical forms of leprosy and household contacts. After sequencing, a specific pipeline was used for preparation and bioinformatics analysis to select heteroplasmic variants. RESULTS: We found 116 variants in at least two of the subtypes of the case group (Borderline Tuberculoid, Borderline Lepromatous, Lepromatous), suggesting a possible clinical significance to these variants. Notably, 15 variants were exclusively found in these three clinical forms, of which five variants stand out for being missense (m.3791T > C in MT-ND1, m.5317C > A in MT-ND2, m.8545G > A in MT-ATP8, m.9044T > C in MT-ATP6 and m.15837T > C in MT-CYB). In addition, we found 26 variants shared only by leprosy poles, of which two are characterized as missense (m.4248T > C in MT-ND1 and m.8027G > A in MT-CO2). CONCLUSION: We found a significant number of variants and heteroplasmy levels in the leprosy patients from our cohort, as well as six genes that may influence leprosy susceptibility, suggesting for the first time that the mitogenome might be involved with the leprosy process, distinction of clinical forms and severity. Thus, future studies are needed to help understand the genetic consequences of these variants.

Clofazimine-induced cutaneous hyperpigmentation as a source of stigma in the treatment of leprosy: A cross-sectional study.

OBJECTIVES: Cutaneous hyperpigmentation is one of the main adverse effects encountered in patients undergoing leprosy treatment with multidrug therapy (WHO-MDT). This adverse effect has been described as intolerable and capable of contributing to social stigma. The objectives of this study were to quantify the variation in skin colour induced by clofazimine during and after treatment and to assess the related stigma. METHODS: This observational cross-sectional study objectively measured skin colour in 51 patients by reading the individual typology angle (ITA°) with a spectrophotometer, followed by the application of the Stigma Scale of the Explanatory Model Interview Catalogue (EMIC). RESULTS: Skin hyperpigmentation was observed in 100% of the individuals. They showed more negative ITA° values in lesion areas than non-lesion areas, particularly in sun-exposed regions. Clofazimine-induced cutaneous hyperpigmentation was not homogeneous and seemed to follow the lesion locations. The mean EMIC score was 18.8 points. CONCLUSION: All patients presented skin hyperpigmentation caused by clofazimine, detectable through spectrophotometry. Hyperpigmentation strongly impacted the social domain, indicating the intersectionality of disease and skin colour stigma, contributing to the social isolation of these patients. Health authorities should consider the negative impact of clofazimine on treatment adherence.

Models for predicting the risk of illness in leprosy contacts in Brazil: Leprosy prediction models in Brazilian contacts.

OBJECTIVE: This study aims to develop and validate predictive models that assess the risk of leprosy development among contacts, contributing to an enhanced understanding of disease occurrence in this population. METHODS: A cohort of 600 contacts of people with leprosy treated at the National Reference Center for Leprosy and Health Dermatology at the Federal University of Uberlândia (CREDESH/HC-UFU) was followed up between 2002 and 2022. The database was divided into two parts: two-third to construct the disease risk score and one-third to validate this score. Multivariate logistic regression models were used to construct the disease score. RESULTS: Of the four models constructed, model 3, which included the variables anti-phenolic glycolipid I immunoglobulin M positive, absence of Bacillus Calmette-Guérin vaccine scar and age ≥60 years, was considered the best for identifying a higher risk of illness, with a specificity of 89.2%, a positive predictive value of 60% and an accuracy of 78%. CONCLUSIONS: Risk prediction models can contribute to the management of leprosy contacts and the systematisation of contact surveillance protocols.

Buruli ulcer, tuberculosis and leprosy: Exploring the One Health dimensions of three most prevalent mycobacterial diseases: A narrative review.

ΟBJECTIVES: Although Buruli ulcer, tuberculosis, and leprosy are the three most common mycobacterial diseases, One Health dimensions of these infections remain poorly understood. This narrative review aims at exploring the scientific literature with respect to the presence of animal reservoir(s) and other environmental sources for the pathogens of these infections, their role in transmission to humans and the research on/practical implementation of One Health relevant control efforts. METHODS: The literature review was conducted using the online databases PubMed, Scopus, ProQuest and Google Scholar, reviewing articles that were written in English in the last 15 years. Grey literature, published by intergovernmental agencies, was also reviewed. RESULTS: For the pathogen of Buruli ulcer, evidence suggests possums as a possible animal reservoir and thus having an active role in disease transmission to humans. Cattle and some wildlife species are deemed as established animal reservoirs for tuberculosis pathogens, with a non-negligible proportion of infections in humans being of zoonotic origin. Armadillos constitute an established animal reservoir for leprosy pathogens with the transmission of the disease from armadillos to humans being deemed possible. Lentic environments, soil and other aquatic sources may represent further abiotic reservoirs for viable Buruli ulcer and leprosy pathogens infecting humans. Ongoing investigation and implementation of public health measures, targeting (sapro)zoonotic transmission can be found in all three diseases. CONCLUSION: Buruli ulcer, tuberculosis and leprosy exhibit important yet still poorly understood One Health aspects. Despite the microbiological affinity of the respective causative mycobacteria, considerable differences in their animal reservoirs, potential environmental sources and modes of zoonotic transmission are being observed. Whether these differences reflect actual variations between these diseases or rather knowledge gaps remains unclear. For improved disease control, further investigation of zoonotic aspects of all three diseases and formulation of One Health relevant interventions is urgently needed.

Any resurgence of leprosy cases in the Togo's post-elimination period? Trend analysis of reported leprosy cases from 2010 to 2022.

BACKGROUND: Leprosy, or Hansen's disease, is a chronic infectious disease caused by Mycobacterium leprae. Togo achieved the target of eliminating leprosy as a public health problem in 2000 (less than 1 case/10 000 population). However, new cases of leprosy are still being reported. The aim of this study was to describe and map trends of leprosy cases notified in Togo from 2010 to 2022. METHODS: This was a descriptive cross-sectional study covering a thirteen-year period from January 1, 2010, to December 31, 2022. The data of the study were leprosy surveillance system's data collected monthly between 2010 and 2022. The estimated number of leprosy cases and the incidence rate of leprosy cases were reported for the whole population by region, by district, by calendar year (2010-2022) and by target sub-population (children under 15, women and people with disabilities). Observed case incidence rates were mapped by health district and by year. RESULTS: From January 1, 2010, to December 31, 2022, 1031 new cases of leprosy were diagnosed in Togo. The median age of subjects was 46 years (interquartile range: 33-60), with extremes from 4 to 96 years. Half the subjects were women (50.7%). Variations in the leprosy incidence rate by year show an increase between 2010 and 2022, from 0.7 cases /100,000 population to 1.1 /100,000 population respectively. From 2010 to 2022, the proportion of cases in children remained low, between 0 and 9%. The proportion of women fluctuated between 39.7% and 67.2% between 2010 and 2017, then stabilized at an average of 50% between 2018 and 2022. The proportion of multi-bacillary leprosy cases increased quasi-linearly between 2010 and 2022, from 70 to 96.6%. Mapping of leprosy cases showed that leprosy was notified in all Togo health districts during the study period, apart from the Lacs district, which reported no leprosy cases. CONCLUSION: Togo has achieved the elimination of leprosy as a public health problem. However, the increase in the number of new leprosy cases and the proportion of leprosy cases in children indicate that transmission of the disease is continuing and that supplementary measures are needed.

Dermoscopic features of nails in Leprosy patients in a tertiary referral hospital in West Java, Indonesia.

INTRODUCTION: Leprosy is a chronic granulomatous infectious disease, mainly affecting the skin and peripheral nerves, caused by the obligate intracellular bacteria Mycobacterium leprae. The disease has been discussed in several review articles in recent research, but as far as we know, only a few have addressed the effects of leprosy on nails, especially those who examine the dermoscopic features of nails in leprosy patients. PURPOSES: We aimed to document nail changes in leprosy patients and identify any particular findings through dermoscopic examination. METHOD: This was an observational study conducted in the Dermatology and Venereology Clinic of Hasan Sadikin Hospital, West Java, Indonesia, from March 2023 through May 2023. All patients have established cases of leprosy, and the diagnosis is based on clinical and bacteriological examinations. Recruitment was done through total sampling. Dermoscopic examination of all fingernails and toenails was performed at 10x magnification using a handheld dermatoscope (Heine DELTA 20 T Dermatoscope) in polarized mode without the linkage fluid to document the dermoscopic features. RESULT: Of a total of 19 patients, 15 had nail changes due to leprosy. Out of 15 patients, 13 patients were male. Patients below 25 years old had more nail changes. Most of the patients had a duration of disease greater than two years. Both fingers and toes were involved in nine patients. In this study, the most common dermoscopic feature found was the longitudinal ridge. Other dermoscopic features found in this study were transverse lines, onycholysis, longitudinal melanonychia, leukonychia, subungual hemorrhage, subungual hyperkeratosis, anonychia, and onychorrexis. CONCLUSION: Nail changes are found in leprosy patients and have a wide variety of clinical appearances. A dermoscopy should be performed to assess nail changes in leprosy.

Plantar pressure distribution and altered postural control in multibacillary leprosy patients.

BACKGROUND: Leprosy is a chronic infectious disease caused by Mycobacterium leprae, predominantly affecting the peripheral nerves, resulting in sensory and motor deficits in the feet. Foot ulcers and imbalances are frequent manifestations in leprosy, often correlating with diminished sensitivity. While clinical scales and monofilament esthesiometers are conventionally utilized to evaluate foot sensitivity and balance in these patients, their discriminatory power is limited and their effectiveness is greatly dependent on the examiner's proficiency. In contrast, baropodometry and posturography offer a more comprehensive evaluation, aiming to preempt potential damage events. This study aimed was to assess the correlation between baropodometry and force plate measurements in leprosy patients and control participants, to improve the prevention and treatment of foot ulcers and complications associated with leprosy. METHODOLOGY: This cross-sectional study was conducted during 2022 and enrolled 39 participants (22 patients with multibacillary leprosy and 17 non-leprosy controls). Demographic data were collected, and a monofilament esthesiometer was used to assess sensory deficits. In addition, physical examinations and balance and plantar pressure tests were conducted. The Student's t-test was used to compare mean and maximum plantar pressures between groups. For most COP variables, a Mann-Whitney Wilcoxon test was used, except for AP amplitude which was analyzed with the Student's t-test due to its normal distribution. The relationship between foot pressure and balance control was assessed using Spearman's correlation, focusing on areas with significant pressure differences between groups. PRINCIPAL FINDINGS: Leprosy patients showed increased pressure in forefoot areas (T1, M1, T2-T5, and M2) and decreased pressure in hindfoot regions (MH and LH) compared to controls. These patients also displayed higher AP and ML amplitudes, suggesting poorer COP control. Correlation analyses between the two groups revealed that foot plantar pressures significantly impact balance control. Specifically, increased T1 region pressures correlated with greater sway in balance tasks, while decreased MH region pressures were linked to reduced COP control. CONCLUSIONS/SIGNIFICANCE: The findings suggest a joint disturbance of plantar pressure distribution and static balance control in leprosy patients. These alterations may increase the risk of tissue injuries, including calluses and deformities, as well as falls.

A case report and literature review: Mycobacterium leprae infection diagnosed by metagenomic next-generation sequencing of cerebrospinal fluid.

BACKGROUND: Leprosy is a chronic infectious disease caused by Mycobacterium leprae (M. leprae) that is responsible for deformities and irreversible peripheral nerve damage and has a broad spectrum of clinical and serological manifestations. Leprosy primarily affects the peripheral nerves and rarely presents with central nervous system involvement. Diagnosing leprosy can still be difficult in some cases, especially when the infection involves uncommon clinical manifestations and extracutaneous sites. Delayed diagnosis and treatment of leprosy may lead to irreversible damage and death. CASE PRESENTATION: We report a case of a 30-year-old female presenting with "repeated high fever with symptoms of headache for 14 days". On the day of admission, physical signs of lost eyebrows and scattered red induration patches all over her body were observed. The patient's diagnosis was based on the clinical characteristics using a combination of metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF) and slit-skin smear. After confirming Listeria meningitis and multibacillary leprosy with erythema nodosum leprosum (ENL), a type 2 reaction, she was treated with ampicillin sodium, dapsone, rifampicin, clofazimine, methylprednisolone, and thalidomide. At the 1-year follow-up, the frequency and severity of headaches have significantly decreased and a good clinical response with improved skin lesions was found. CONCLUSION: This case highlights the importance of considering leprosy, which is a rare and underrecognized disease, in the differential diagnosis of skin rashes with rheumatic manifestations, even in areas where the disease is not endemic, and physicians should be alerted about the possibility of central nervous system infections. In addition, mNGS can be used as a complementary diagnostic tool to traditional diagnostic methods to enhance the diagnostic accuracy of leprosy.

The PEP++ study protocol: a cluster-randomised controlled trial on the effectiveness of an enhanced regimen of post-exposure prophylaxis for close contacts of persons affected by leprosy to prevent disease transmission.

BACKGROUND: Leprosy is an infectious disease with a slow decline in global annual caseload in the past two decades. Active case finding and post-exposure prophylaxis (PEP) with a single dose of rifampicin (SDR) are recommended by the World Health Organization as measures for leprosy elimination. However, more potent PEP regimens are needed to increase the effect in groups highest at risk (i.e., household members and blood relatives, especially of multibacillary patients). The PEP++ trial will assess the effectiveness of an enhanced preventive regimen against leprosy in high-endemic districts in India, Brazil, Bangladesh, and Nepal compared with SDR-PEP. METHODS: The PEP++ study is a cluster-randomised controlled trial in selected districts of India, Brazil, Bangladesh, and Nepal. Sub-districts will be allocated randomly to the intervention and control arms. Leprosy patients detected from 2015 - 22 living in the districts will be approached to list their close contacts for enrolment in the study. All consenting participants will be screened for signs and symptoms of leprosy and tuberculosis (TB). In the intervention arm, eligible contacts receive the enhanced PEP++ regimen with three doses of rifampicin (150 - 600 mg) and clarithromycin (150 - 500 mg) administered at four-weekly intervals, whereas those in the control arm receive SDR-PEP. Follow-up screening for leprosy will be done for each individual two years after the final dose is administered. Cox' proportion hazards analysis and Poisson regression will be used to compare the incidence rate ratios between the intervention and control areas as the primary study outcome. DISCUSSION: Past studies have shown that the level of SDR-PEP effectiveness is not uniform across contexts or in relation to leprosy patients. To address this, a number of recent trials are seeking to strengthen PEP regimens either through the use of new medications or by increasing the dosage of the existing ones. However, few studies focus on the impact of multiple doses of chemoprophylaxis using a combination of antibiotics. The PEP++ trial will investigate effectiveness of both an enhanced regimen and use geospatial analysis for PEP administration in the study communities. TRIAL REGISTRATION: NL7022 on the Dutch Trial Register on April 12, 2018. Protocol version 9.0 updated on 18 August 2022 https://www.onderzoekmetmensen.nl/en/trial/23060.

Focal slowing of nerve conduction velocity in leprosy patients unveiled through multisegmented nerve analysis.

BACKGROUND AND AIMS: Leprosy is a chronic infectious disease caused by Mycobacterium leprae (M. leprae), an intracellular bacillus that systematically invades the peripheral nerves. Diagnosing leprosy neuropathy is still a defying skill, and late diagnosis and treatment are still a reality. Based on the biological characteristics of M. leprae, particularly its preference for invading the Schwann cells localized at the coldest areas of human body, we hypothesized that these areas have focal demyelination that may escape detection through standard nerve conduction studies (NCSs) protocols. METHODS: Twenty-five patients with confirmed multibacillary leprosy and 14 controls were accessed. A multisegmented NCS protocol (MP) was performed, targeting short segments through the coldest areas, to identify focal areas of slowed conduction velocity. The effectiveness of this multisegmented protocol was compared to the standard protocol (SP) to detect abnormalities. RESULTS: All leprosy patients presented an abnormal study with the MP, contrasting to 19 with the SP. The most frequent NCS pattern was an asymmetric neuropathy with focal slowing of conduction velocity, found in 23 out of 25 leprosy patients. Significant differences favoring the proposed method were observed when comparing the MP with the SP. Notably, the MP increased the sensitivity to detect abnormalities by 122%, 133%, and 257% for the median, peroneal, and tibial nerves, respectively. MP also increases sensitivity to detect focal abnormalities in the ulnar nerve. INTERPRETATION: The MP protocol significantly increases the sensitivity of NCSs to detect neurophysiological abnormalities in leprosy neuropathy.

Body map stories from Colombia: experiences of people affected by leprosy and the influence of peers during diagnosis and treatment.

INTRODUCTION: Almost one third of people affected by leprosy in Colombia suffer from disability, which often results from delayed diagnosis and treatment. We aimed to explore the experience of people affected by leprosy during the process of diagnosis and treatment and if and how this experience was influenced by peers. METHODS: A qualitative study using body map stories was conducted from October 2019 to February 2020 in Colombia. Adult people affected by leprosy were recruited through patient associations in different cities. We conducted three sessions with an average duration of 2-3 h per participant, during which the participants created a painted map of their body and chose symbols to represent their experience, while being engaged in an informal interview. The sessions were audio recorded, transcribed verbatim and analyzed thematically by an interdisciplinary team, consisting of physicians, social workers and a person affected by leprosy. RESULTS: The 17 study participants (11 female) were aged 20 to 70 years. Leprosy-related manifestations ranged from no to advanced disability. Some participants were active members of associations for people affected by leprosy. Three main themes were identified during analysis: (1) A long pathway to diagnosis, (2) Therapy as a double-edged sword and (3) The influence of other people affected by leprosy. The participants described an often years-long process until being diagnosed, which was marked by insecurities, repeated misdiagnosis, and worsening mental and physical health. Delayed diagnosis was related to late health care seeking, but also to inadequate health communication, lack of leprosy-related knowledge and negligence among health care workers. A high desire to cure motivated the participants to take their medication rigorously, despite the high treatment burden. Support from peers, either within the own social environment or provided from associations, contributed to a faster diagnosis and increased therapy adherence. Peers helped to recognize the symptoms, urged patients to seek care, recommended physicians with leprosy-related knowledge and provided a realistic example of both disease severity and curability. CONCLUSION: People affected by leprosy experience a significant burden during the process of diagnosis and treatment. Involving well-trained peers could foster early diagnosis, treatment compliance and prevention of disability.

New threats from an old foe: Evaluating the risk to the blood supply due to increasing incidence and endemicity of leprosy in the United States.

Leprosy (i.e., Hansen's disease) is a chronic disease secondary to infection with either Mycobacterium leprae or M. lepromatosis. While the incidence of this disease is decreasing across the world, there is mounting evidence that it might be increasing, and becoming endemic, in the United States. Leprosy was once considered a potential threat to the blood supply, and while this threat has not borne out, it is worth revisiting the available data to assess whether it may pose a threat in the future. Herein, we discuss the evidence for and against the potential for transfusion-transmission of leprosy, and highlight future areas of research to further elucidate this possibility.

Spatiotemporal pattern of leprosy in southwest China from 2010 to 2020: an ecological study.

BACKGROUND: Despite many efforts to control leprosy worldwide, it is still a significant public health problem in low- and middle-income regions. It has been endemic in China for thousands of years, and southwest China has the highest leprosy burden in the country. METHODS: This observational study was conducted with all newly detected leprosy cases in southwest China from 2010 to 2020. Data were extracted from the Leprosy Management Information System (LEPMIS) database in China. The Joinpoint model was used to determine the time trends in the study area. Spatial autocorrelation statistics was performed to understand spatial distribution of leprosy cases. Spatial scan statistics was applied to identify significant clusters with high rate. RESULTS: A total of 4801 newly detected leprosy cases were reported in southwest China over 11 years. The temporal trends declined stably. The new case detection rate (NCDR) dropped from 4.38/1,000,000 population in 2010 to 1.25/1,000,000 population in 2020, with an average decrease of 12.24% (95% CI: -14.0 to - 10.5; P < 0.001). Results of global spatial autocorrelation showed that leprosy cases presented clustering distribution in the study area. Most likely clusters were identified during the study period and were frequently located at Yunnan or the border areas between Yunnan and Guizhou Provinces. Secondary clusters were always located in the western counties, the border areas between Yunnan and Sichuan Provinces. CONCLUSIONS: Geographic regions characterized by clusters with high rates were considered as leprosy high-risk areas. The findings of this study could be used to design leprosy control measures and provide indications to strengthen the surveillance of high-risk areas. These areas should be prioritized in the allocation of resources.