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Introduction: Patients with the multibacillary form of leprosy can develop reactional episodes of acute inflammation, known as erythema nodosum leprosum (ENL), which are characterized by the appearance of painful cutaneous nodules and systemic symptoms. Neutrophils have been recognized to play a role in the pathogenesis of ENL, and recent global transcriptomic analysis revealed neutrophil-related processes as a signature of ENL skin lesions. Methods: In this study, we expanded this analysis to the blood compartment, comparing whole blood transcriptomics of patients with non-reactional lepromatous leprosy at diagnosis (LL, n=7) and patients with ENL before administration of anti-reactional treatment (ENL, n=15). Furthermore, a follow-up study was performed with patients experiencing an ENL episode at the time of diagnosis and after 7 days of thalidomide treatment (THAL, n=10). Validation in an independent cohort (ENL=8; LL=7) was performed by RT-qPCR. Results: An enrichment of neutrophil activation and degranulation-related genes was observed in the ENL group, with the gene for the neutrophil activation marker CD177 being the most enriched gene of ENL episode when compared to its expression in the LL group. A more pro-inflammatory transcriptome was also observed, with increased expression of genes related to innate immunity. Validation in an independent cohort indicated that S100A8 expression could discriminate ENL from LL. Supernatants of blood cells stimulated in vitro with Mycobacterium leprae sonicate showed higher levels of CD177 compared to the level of untreated cells, indicating that the leprosy bacillus can activate neutrophils expressing CD177. Of note, suggestive higher CD177 protein levels were found in the sera of patients with severe/moderate ENL episodes when compared with patients with mild episodes and LL patients, highlighting CD177 as a potential systemic marker of ENL severity that deserves future confirmation. Furthermore, a follow-up study was performed with patients at the time of ENL diagnosis and after 7 days of thalidomide treatment (THAL, n=10). Enrichment of neutrophil pathways was sustained in the transcriptomic profile of patients undergoing treatment; however, important immune targets that might be relevant to the effect of thalidomide at a systemic level, particularly NLRP6 and IL5RA, were revealed. Discussion: In conclusion, our study reinforces the key role played by neutrophils in ENL pathogenesis and shed lights on potential diagnostic candidates and novel therapeutic targets that could benefit patients with leprosy.

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Abstract Brazil has a huge number of cases and deaths due to coronavirus disease 2019 (COVID-19); however, few studies have dealt with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among familial contacts in Brazil. Here, we report our findings on transmission in a family-based study in Bauru, São Paulo, Brazil. The study, conducted from July to November 2020, comprised 974 individuals with 233 index patients and 741 familial contacts. Familial contacts were evaluated using the rapid COVID-19 Ag ECO and reverse transcription-polymerase chain reaction (RT-PCR) tests immediately after the index patient diagnosis. The antigen-based rapid test was validated in 121 individuals using RT-PCR as the gold standard. Additionally, 30 days later, familial contacts were evaluated for IgM and IgG antibodies against SARS-CoV-2. We found 333 cases of COVID-19 among familial contacts (44.9%). A positive correlation was observed between the time elapsed from the onset of symptoms until the index patient's COVID-19 testing and the number of family contacts infected by SARS-CoV-2. Early SARS-CoV-2 testing and familial contact evaluation are relevant strategies to contain transmission.

Resumo O Brasil apresenta um alto número de casos e óbitos por coronavírus (COVID-19), apesar disso, poucos estudos tratavam da infecção pelo coronavirus-2 causador de síndrome respiratória aguda grave (SARS-CoV-2) entre contatos familiares no Brasil. Relatamos aqui nossos achados sobre a transmissão de SARS-CoV-2 em um estudo de base familiar de Bauru, no estado de São Paulo, Brasil. O estudo foi realizado de julho a novembro de 2020 e compreendeu 974 indivíduos, sendo 233 pacientes índice e 741 contatos familiares. Os contatos familiares foram avaliados por meio do teste rápido COVID-19 Ag ECO Test e RT-PCR imediatamente após o diagnóstico do paciente índice. O uso do teste rápido baseado em antígeno foi validado em 121 indivíduos utilizando RT-PCR como padrão ouro. Adicionalmente, 30 dias após a avaliação inicial, os contatos familiares foram avaliados quanto à presença de anticorpos IgM e IgG contra SARS-CoV-2. Encontramos 333 casos de COVID-19 entre contatos familiares (44,9%). Observamos uma correlação positiva entre o tempo decorrido entre o início dos sintomas e o teste para COVID-19 do paciente índice e o número de contatos familiares infectados por SARS-CoV-2. A testagem precoce da infecção por SARS-CoV-2 e a avaliação de contatos familiares são estratégias relevantes para conter a transmissão.

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Brazil has a huge number of cases and deaths due to coronavirus disease 2019 (COVID-19); however, few studies have dealt with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among familial contacts in Brazil. Here, we report our findings on transmission in a family-based study in Bauru, São Paulo, Brazil. The study, conducted from July to November 2020, comprised 974 individuals with 233 index patients and 741 familial contacts. Familial contacts were evaluated using the rapid COVID-19 Ag ECO and reverse transcription-polymerase chain reaction (RT-PCR) tests immediately after the index patient diagnosis. The antigen-based rapid test was validated in 121 individuals using RT-PCR as the gold standard. Additionally, 30 days later, familial contacts were evaluated for IgM and IgG antibodies against SARS-CoV-2. We found 333 cases of COVID-19 among familial contacts (44.9%). A positive correlation was observed between the time elapsed from the onset of symptoms until the index patient's COVID-19 testing and the number of family contacts infected by SARS-CoV-2. Early SARS-CoV-2 testing and familial contact evaluation are relevant strategies to contain transmission.

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Introduction: Leprosy reactions (LR) are severe episodes of intense activation of the host inflammatory response of uncertain etiology, today the leading cause of permanent nerve damage in leprosy patients. Several genetic and non-genetic risk factors for LR have been described; however, there are limited attempts to combine this information to estimate the risk of a leprosy patient developing LR. Here we present an artificial intelligence (AI)-based system that can assess LR risk using clinical, demographic, and genetic data. Methods: The study includes four datasets from different regions of Brazil, totalizing 1,450 leprosy patients followed prospectively for at least 2 years to assess the occurrence of LR. Data mining using WEKA software was performed following a two-step protocol to select the variables included in the AI system, based on Bayesian Networks, and developed using the NETICA software. Results: Analysis of the complete database resulted in a system able to estimate LR risk with 82.7% accuracy, 79.3% sensitivity, and 86.2% specificity. When using only databases for which host genetic information associated with LR was included, the performance increased to 87.7% accuracy, 85.7% sensitivity, and 89.4% specificity. Conclusion: We produced an easy-to-use, online, free-access system that identifies leprosy patients at risk of developing LR. Risk assessment of LR for individual patients may detect candidates for close monitoring, with a potentially positive impact on the prevention of permanent disabilities, the quality of life of the patients, and upon leprosy control programs.

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BACKGROUND: Leprosy, caused by Mycobacterium leprae, is a public health problem in Brazil that affects peripheral nerves, resulting in physical disabilities. During host-pathogen interactions, the immune response determines leprosy outcomes from a localised (paucibacillary) form to a disseminated (multibacillary) form. The recognition of M. leprae involves the DC-SIGN receptor, which is present on the dendritic cells (DCs) and participates in immune activation. OBJECTIVES: To evaluate the association of polymorphisms in the promoter region of the gene encoding DC-SIGN (CD209) and the clinical form of leprosy, and to investigate its functional effects. METHODS: The study population included 406 leprosy patients from an endemic area in Brazil [310 multibacillary (MB); 96 paucibacillary (PB)]. A functional evaluation based on the effects of the single nucleotide variant (SNV) associated with PB leprosy on the specific immune response was also performed. RESULTS: The GA genotype and the presence of the A allele of rs735240 (-939G>A) were associated with PB leprosy [OR: 2.09 (1.18-3.69) and 1.84 (1.07-3.14), respectively]. Carriers of the A allele showed reduced expression of CD209 and TGF-ß1 in leprosy lesions in comparison with individuals with GG genotype, in addition to a higher response to the Mitsuda test. CONCLUSION: These data suggest that rs735240 influences the immune response against M. leprae and clinical presentation of leprosy.

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Lobomycosis is a chronic disease caused by Lacazia loboi, which is endemic to the Amazon rainforest, where it affects forest dwellers in Brazil. There is no disease control program and no official therapeutic protocol. This situation contributes to an unknown disease prevalence and unmet needs of people disabled by this disease who seek access to treatment. This review provides an update on the subject with an emphasis on therapeutic advances in humans. All relevant studies that addressed epidemiology, diagnosis, or therapeutics of lobomycosis were considered. Seventy-one articles published between 1931 and 2021 were included for a narrative literature review on the epidemiology and quest for a cure. An effective therapy for lobomycosis has been found following decades of research led by the State Dermatology Program of Acre in the Amazon rainforest, where the largest number of cases occur. This discovery opened new avenues for future studies. The main recommendations here, addressed to the Brazilian Ministry of Health, are for lobomycosis to become a reportable disease to ensure that disease prevalence is measured, and that it be prioritized such that affected individuals may access treatment free-of-charge.

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BACKGROUND Leprosy, caused by Mycobacterium leprae, is a public health problem in Brazil that affects peripheral nerves, resulting in physical disabilities. During host-pathogen interactions, the immune response determines leprosy outcomes from a localised (paucibacillary) form to a disseminated (multibacillary) form. The recognition of M. leprae involves the DC-SIGN receptor, which is present on the dendritic cells (DCs) and participates in immune activation. OBJECTIVES To evaluate the association of polymorphisms in the promoter region of the gene encoding DC-SIGN (CD209) and the clinical form of leprosy, and to investigate its functional effects. METHODS The study population included 406 leprosy patients from an endemic area in Brazil [310 multibacillary (MB); 96 paucibacillary (PB)]. A functional evaluation based on the effects of the single nucleotide variant (SNV) associated with PB leprosy on the specific immune response was also performed. RESULTS The GA genotype and the presence of the A allele of rs735240 (-939G>A) were associated with PB leprosy [OR: 2.09 (1.18-3.69) and 1.84 (1.07-3.14), respectively]. Carriers of the A allele showed reduced expression of CD209 and TGF-β1 in leprosy lesions in comparison with individuals with GG genotype, in addition to a higher response to the Mitsuda test. CONCLUSION These data suggest that rs735240 influences the immune response against M. leprae and clinical presentation of leprosy.

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BACKGROUND: Leprosy has been treated with multidrug therapy (MDT) distributed for free across the globe and regarded as highly efficient. However, the impossibility to grow M. leprae in axenic media has historically impaired assessment of M. leprae resistance, a parameter only recently detectable through molecular methods. METHODS: A systematic, population-based search for M. leprae resistance in suspected leprosy relapse cases and contacts was performed in Prata Village, an isolated, hyper-endemic former leprosy colony located in the Brazilian Amazon. Results led to an extended active search involving the entire Prata population. Confirmed leprosy cases were investigated for bacterial resistance using a combination of in vivo testing and direct sequencing of resistance genes folP1, rpoB and gyrA. Molecular epidemiology analysis was performed using data from 17 variable number tandem repeats (VNTR). RESULTS: M. leprae was obtained from biopsies of 37 leprosy cases (18 relapses and 19 new); 16 (43.24%) displayed drug-resistance variants. Multi-drug resistance to rifampicin and dapsone was observed in 8 relapses and 4 new cases. Single resistance to rifampicin was detected in one new case. Resistance to dapsone was present in two relapses and one new case. Combined molecular resistance and VNTR data revealed evidence of intra-familial primary transmission of resistant M. leprae. CONCLUSIONS: A comprehensive, population-based systematic approach to investigate M. leprae resistance in a unique population revealed an alarming scenario of emergence and transmission of resistant strains. These findings may be used for the development of new strategies for surveillance of drug resistance in other populations.

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BACKGROUND: The multidrug therapy (MDT) for leprosy treatment adopted by Brazil in the 1990s was important for reducing leprosy in the country; however, recurrent cases remained problematic. Mechanisms involved in leprosy recurrence are heterogeneous and can be sorted into three groups: insufficient therapy, bacillary persistence and new infections. This study aimed to analyse the time interval of leprosy recurrence in relation to the therapeutic scheme in the state of Acre. The hypotheses were as follows: 1) treatments (a) rifampicin, ofloxacin and minocycline (ROM) and (b) dapsone (DDS) have a short leprosy recurrence time, 2) treatments based on MDT have a long leprosy recurrence time, 3) there is a dose-response relationship between MDT and the time interval between leprosy episodes. METHODS: This retrospective cohort study included 201 patients with a second episode of clinical leprosy at the reference centers for leprosy control in the state of Acre. Exposure was the type of therapeutic scheme as follows: 1) ROM, 2) DDS, 3) MDT0-9 doses, 4) MDT10-19 doses, 5) MDT20-29 doses, and 6) MDT30+ doses. Outcome was the time interval between release from treatment and a diagnosis of a recurrent leprosy case. Incidence rate ratios and relative risk Poisson regressions adjusted by age and sex were calculated with 95% confidence intervals. RESULTS: The 201 patients studied during this retrospective follow-up resulted in a total of 224 cases of recurrent leprosy. Incidence rate ratios within this therapeutic scheme were as follows: 3.3 (2.39, 4.2; ROM/MDT30+), 1.12 (0.33, 1.92; DDS/MDT30+), 2.17 (1.39, 2.94; MDT0-9/MDT30+), 1.94 (1.13, 2.75; MDT10-19/MDT30+) and 1.26 (0.47, 2.05; MDT20-29/MDT30+). Relative risk Poisson regressions showed a protective effect of MDT30+ in comparison with ROM (0.22; 0.07, 0.72), MDT0-9 (0.42; 0.21, 0.85), and MDT10-19 (0.44; 0.21, 0.92). No differences among MDT30+ and DDS (0.71; 0.36, 1.41) and MDT20-29 (0.76; 0.38, 1.49) were observed. CONCLUSIONS: New infection is an important-yet neglected-mechanism in leprosy recurrence in the state of Acre and can challenge the leprosy elimination plan in Brazil. MDT with few doses might be associated with leprosy recurrence due to insufficient therapy or bacillary persistence.

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BACKGROUND: The multidrug therapy (MDT) for leprosy treatment adopted by Brazil in the 1990s was important for reducing leprosy in the country; however, recurrent cases remained problematic. Mechanisms involved in leprosy recurrence are heterogeneous and can be sorted into three groups insufficient therapy, bacillary persistence and new infections. This study aimed to analyse the time interval of leprosy recurrence in relation to the therapeutic scheme in the state of Acre. The hypotheses were as follows 1) treatments (a) rifampicin, ofloxacin and minocycline (ROM) and (b) dapsone (DDS) have a short leprosy recurrence time, 2) treatments based on MDT have a long leprosy recurrence time, 3) there is a dose-response relationship between MDT and the time interval between leprosy episodes. METHODS: This retrospective cohort study included 201 patients with a second episode of clinical leprosy at the reference centers for leprosy control in the state of Acre. Exposure was the type of therapeutic scheme as follows 1) ROM, 2) DDS, 3) MDT0-9 doses, 4) MDT10-19 doses, 5) MDT20-29 doses, and 6) MDT30+ doses. Outcome was the time interval between release from treatment and a diagnosis of a recurrent leprosy case. Incidence rate ratios and relative risk Poisson regressions adjusted by age and sex were calculated with 95% confidence intervals. RESULTS: The 201 patients studied during this retrospective follow-up resulted in a total of 224 cases of recurrent leprosy. Incidence rate ratios within this therapeutic scheme were as follows 3.3 (2.39, 4.2; ROM/MDT30+), 1.12 (0.33, 1.92; DDS/MDT30+), 2.17 (1.39, 2.94; MDT0-9/MDT30+), 1.94 (1.13, 2.75; MDT10-19/MDT30+) and 1.26 (0.47, 2.05; MDT20-29/MDT30+). Relative risk Poisson regressions showed a protective effect of MDT30+ in comparison with ROM (0.22; 0.07, 0.72), MDT0-9 (0.42; 0.21, 0.85), and MDT10-19 (0.44; 0.21, 0.92). No differences among MDT30+ and DDS (0.71; 0.36, 1.41) and MDT20-29 (0.76; 0.38, 1.49) were observed. CONCLUSIONS: New infection is an important-yet neglected-mechanism in leprosy recurrence in the state of Acre and can challenge the leprosy elimination plan in Brazil. MDT with few doses might be associated with leprosy recurrence due to insufficient therapy or bacillary persistence.

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This study evaluated the immune response of nude and BALB/c mice inoculated in the footpads (FP) with Mycobacterium leprae after 3, 5 and 8 months. At each timepoint peritoneal cells, peripheral blood, FP and popliteal lymph nodes (PLN) were collected. Peritoneal cell cultures were performed to measure the H2O2, O2−, NO, IL­2, IL­4, IL­10, IL­12, IFN­Î³ and TNF levels. Serum levels of anti­PGL­I antibodies were also quantified. The results showed that the infection was progressive in nude mice with bacterial multiplication, development of macroscopic lesions in the FP and presence of bacilli in the PLN at 8 months. In BALB/c mice, the infection reached a plateau of bacillary multiplication at 5 months and regressed at 8 months. Histopathological analysis of FP revealed a mononuclear inflammatory infiltrate with a large number of neutrophils at 5 months, with a higher number in nude mice. At 8 months, the number of neutrophils decreased and the infiltrate was predominantly mononuclear in both mouse strains. There was no H2O2, O2−, IL­2, IL­4, IL­10 and IFN­Î³ production in the course of infection in nude mice; however, in BALB/c, O2− and IL­12 production was higher at 5 months and NO, IFN­Î³ and TNF production was higher at 8 months when there was a decrease in the number of bacilli. The level of anti­PGL­I antibodies was higher in BALB/c mice. Thus, nude and BALB/c mice can be used as experimental models for the study of various aspects of leprosy(AU).

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BACKGROUND Leprosy is a chronic infectious disease caused by Mycobacterium leprae, and compromises the skin and peripheral nerves. This disease has been classified as multibacillary (MB) or paucibacillary (PB) depending on the host immune response. Genetic epidemiology studies in leprosy have shown the influence of human genetic components on the disease outcomes. OBJECTIVES We conducted an association study for IL2RA and TGFB1 genes with clinical forms of leprosy based on two case-control samples. These genes encode important molecules for the immunosuppressive activity of Treg cells and present differential expressions according to the clinical forms of leprosy. Furthermore, IL2RA is a positional candidate gene because it is located near the 10p13 chromosome region, presenting a linkage peak for PB leprosy. METHODS A total of 885 leprosy cases were included in the study; 406 cases from Rondonópolis County (start population), a hyperendemic region for leprosy in Brazil, and 479 cases from São Paulo state (replication population), which has lower epidemiological indexes for the disease. We tested 11 polymorphisms in the IL2RA gene and the missense variant rs1800470 in the TGFB1 gene. FINDINGS The AA genotype of rs2386841 in IL2RA was associated with the PB form in the start population. The AA genotype of rs1800470 in TGFB1 was associated with the MB form in the start population, and this association was confirmed for the replication population. MAIN CONCLUSIONS We demonstrated, for the first time, an association data with the PB form for a gene located on chromosome 10. In addition, we reported the association of TGFB1 gene with the MB form. Our results place these genes as candidates for validation and replication studies in leprosy polarisation.

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This study aimed to identify the distribution pattern of leprosy in a hyperendemic municipality in Brazil and determine its relationship with the clinico-epidemiological situation over 11 years. The geographic information system, MapInfo, spatial scan statistics and the Moran I index were used to analyze new cases. The digital cartographic base was used to map clusters of new paucibacillary and multibacillary cases and cases in minors under 15 years old. Socioeconomic indicators are shown using the choropleth mapping technique. A reduction in the detection coefficient, increases in high-risk spatial clusters, marked changes in the distribution of high-risk and low-risk clusters, and high-risk clusters of minors under 15 years old were observed from 2006 to 2010, showing recent illness, the presence of active foci, and overlapping of high-risk clusters of multibacillary infection in minors under 15 years old. Leprosy remains a public health problem in Rondonópolis, Mato Grosso State; the high-risk areas require an intensification of control measures and active search strategies to detect new cases.

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Leprosy patients may present reactional episodes classified as type I or reversal reaction and type II or erythema nodosum leprosum. Early diagnosis of these reactions is hampered by lack of diagnostic tests. This study aimed at evaluating anti­Mycobacterium leprae antibody levels in reactional and nonreactional leprosy patients at the time of diagnosis. Clinical data and serum samples of 224 patients diagnosed between 2009 and 2010 were collected in the municipality of Rondonópolis-MTBR. Quantification of anti­phenolic glycolipid-1 (PGL-1) IgM antibodies of M. leprae was obtained by the enzyme-linked immunosorbent assay method and anti­natural octyl disacharide-leprosy IDRI diagnostic (NDO-LID-1) IgM/IgG semiquantitative rapid test. We obtained low serological levels of anti­PGL-1 and anti­NDO-LID-1 for tuberculoid (T) (1.56% and 15.62%) and borderline tuberculoid (BT) patients (7.95% and 26.13%), medium levels in the borderline-borderline (BB) (47.91% and 68.75%), and high levels in lepromatous (LL) (93.33% and 100%) and borderline-lepromatous (BL) (88.0% and 100%). When comparing the reactional groups (RI and RII) with without reaction (WR) group at the time of diagnosis, we observed a statistically significant difference between the groups; patients with RII presented higher serological response: 66.66% anti­PGL-1 and 91.66% anti­NDO-LID-1. In respect to patients who developed a reaction after the initial diagnosis, they also showed significant positivity for both anti­PGL-1 and anti­NDO-LID-1 in comparison to the patients who stayed without reaction in the study period (P < 0.0001). These results allow us to conclude that serological tests may contribute to an early diagnosis of RII and that the anti­NDO-LID-1 test was demonstrated to be a better indicator.

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Abstract: This study aimed to identify the distribution pattern of leprosy in a hyperendemic municipality in Brazil and determine its relationship with the clinico-epidemiological situation over 11 years. The geographic information system, MapInfo, spatial scan statistics and the Moran I index were used to analyze new cases. The digital cartographic base was used to map clusters of new paucibacillary and multibacillary cases and cases in minors under 15 years old. Socioeconomic indicators are shown using the choropleth mapping technique. A reduction in the detection coefficient, increases in high-risk spatial clusters, marked changes in the distribution of high-risk and low-risk clusters, and high-risk clusters of minors under 15 years old were observed from 2006 to 2010, showing recent illness, the presence of active foci, and overlapping of high-risk clusters of multibacillary infection in minors under 15 years old. Leprosy remains a public health problem in Rondonópolis, Mato Grosso State; the high-risk areas require an intensification of control measures and active search strategies to detect new cases.

Resumo: O estudo teve como objetivos identificar o padrão de distribuição da hanseníase em um município brasileiro hiperendêmico e determinar a relação com o quadro clínico-epidemiológico ao longo de 11 anos. Os casos novos foram analisados com o sistema de informação geográfica, MapInfo, estatística scan espacial e índice Moran I. A base cartográfica digital foi usada para mapear os clusters de casos paucibacilares e multibacilares novos e casos em menores de 15 anos. Os indicadores socioeconômicos são mostrados através da técnica de mapeamento coroplético. Entre 2006 e 2010, foram observados uma redução no coeficiente de detecção, aumento no clusters espaciais de alto risco, mudanças marcantes na distribuição de clusters de alto e baixo risco e clusters de alto risco em menores de 15 anos, sugerindo doença recente, a presença de focos ativos e a sobreposição de clusters de alto risco para infecção multibacilar em menores de 15 anos. A hanseníase persiste enquanto problema de saúde pública em Rondonópolis, Mato Grosso; as áreas de alto risco exigem a intensificação de medidas de controle, além de estratégias de busca ativa para detectar casos novos.

Resumen: Este estudio tuvo como objetivo identificar la distribución de los patrones de lepra en una municipalidad hiperendémica en Brasil y determinar su relación con la situación clínico-epidemiológica durante 11 años. El sistema de información geográfica, MapInfo, estadísticas de escaneo espacial y el índice de Moran se usaron para analizar nuevos casos. La base cartográfica digital se usó para mapear clústeres de nuevos casos multibacilares y paucibacilares, así como casos en menores por debajo de 15 años de edad. Los indicadores socioeconómicos se presentan usando la técnica de mapeo de coropletas. La reducción en la detección del coeficiente, se incrementa en los clústeres de alto riesgo espaciales, asimismo, se observaron de 2006 a 2010 cambios considerables en la distribución de los clústeres de alto riesgo y bajo riesgo, así como en clústeres de alto riesgo con menores con menos de 15 años de edad, mostrando los casos de enfermedad reciente la presencia de focos activos, así como solapando clústeres de alto riesgo de infección multibacilar en menores por debajo de los 15 años de edad. La lepra continúa siendo un problema de salud pública en Rondonópolis, Mato Grosso; las áreas de alto riesgo necesitan una intensificación de las medidas de control y una búsqueda activa de estrategias, con el fin de detectar nuevos casos.

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BACKGROUND Leprosy is a chronic infectious disease caused by Mycobacterium leprae, and compromises the skin and peripheral nerves. This disease has been classified as multibacillary (MB) or paucibacillary (PB) depending on the host immune response. Genetic epidemiology studies in leprosy have shown the influence of human genetic components on the disease outcomes. OBJECTIVES We conducted an association study for IL2RA and TGFB1 genes with clinical forms of leprosy based on two case-control samples. These genes encode important molecules for the immunosuppressive activity of Treg cells and present differential expressions according to the clinical forms of leprosy. Furthermore, IL2RA is a positional candidate gene because it is located near the 10p13 chromosome region, presenting a linkage peak for PB leprosy. METHODS A total of 885 leprosy cases were included in the study; 406 cases from Rondonópolis County (start population), a hyperendemic region for leprosy in Brazil, and 479 cases from São Paulo state (replication population), which has lower epidemiological indexes for the disease. We tested 11 polymorphisms in the IL2RA gene and the missense variant rs1800470 in the TGFB1 gene. FINDINGS The AA genotype of rs2386841 in IL2RA was associated with the PB form in the start population. The AA genotype of rs1800470 in TGFB1 was associated with the MB form in the start population, and this association was confirmed for the replication population. MAIN CONCLUSIONS We demonstrated, for the first time, an association data with the PB form for a gene located on chromosome 10. In addition, we reported the association of TGFB1 gene with the MB form. Our results place these genes as candidates for validation and replication studies in leprosy polarisation.

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Abstract Leprosy, whose etiological agent is Mycobacterium leprae, is a chronic infectious disease that mainly affects the skin and peripheral nervous system. The diagnosis of leprosy is based on clinical evaluation, whereas histopathological analysis and bacilloscopy are complementary diagnostic tools. Quantitative PCR (qPCR), a current useful tool for diagnosis of infectious diseases, has been used to detect several pathogens including Mycobacterium leprae. The validation of this technique in a robust set of samples comprising the different clinical forms of leprosy is still necessary. Thus, in this study samples from 126 skin biopsies (collected from patients on all clinical forms and reactional states of leprosy) and 25 slit skin smear of leprosy patients were comparatively analyzed by qPCR (performed with primers for the RLEP region of M. leprae DNA) and routine bacilloscopy performed in histological sections or in slit skin smear. Considering clinical diagnostic as the gold standard, 84.9% of the leprosy patients were qPCR positive in skin biopsies, resulting in 84.92% sensitivity, with 84.92 and 61.22% positive (PPV) and negative (NPV) predictive values, respectively. Concerning bacilloscopy of histological sections (BI/H), the sensitivity was 80.15% and the PPV and NPV were 80.15 and 44.44%, respectively. The concordance between qPCR and BI/H was 87.30%. Regarding the slit skin smear, 84% of the samples tested positive in the qPCR. Additionally, qPCR showed 100% specificity, since all samples from different mycobacteria, from healthy individuals, and from other granulomatous diseases presented negative results. In conclusion, the qPCR technique for detection of M. leprae using RLEP primers proved to be specific and sensitive, and qPCR can be used as a complementary test to diagnose leprosy irrespective of the clinical form of disease.

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Leprosy, whose etiological agent is Mycobacterium leprae, is a chronic infectious disease that mainly affects the skin and peripheral nervous system. The diagnosis of leprosy is based on clinical evaluation, whereas histopathological analysis and bacilloscopy are complementary diagnostic tools. Quantitative PCR (qPCR), a current useful tool for diagnosis of infectious diseases, has been used to detect several pathogens including Mycobacterium leprae. The validation of this technique in a robust set of samples comprising the different clinical forms of leprosy is still necessary. Thus, in this study samples from 126 skin biopsies (collected from patients on all clinical forms and reactional states of leprosy) and 25 slit skin smear of leprosy patients were comparatively analyzed by qPCR (performed with primers for the RLEP region of M. leprae DNA) and routine bacilloscopy performed in histological sections or in slit skin smear. Considering clinical diagnostic as the gold standard, 84.9% of the leprosy patients were qPCR positive in skin biopsies, resulting in 84.92% sensitivity, with 84.92 and 61.22% positive (PPV) and negative (NPV) predictive values, respectively. Concerning bacilloscopy of histological sections (BI/H), the sensitivity was 80.15% and the PPV and NPV were 80.15 and 44.44%, respectively. The concordance between qPCR and BI/H was 87.30%. Regarding the slit skin smear, 84% of the samples tested positive in the qPCR. Additionally, qPCR showed 100% specificity, since all samples from different mycobacteria, from healthy individuals, and from other granulomatous diseases presented negative results. In conclusion, the qPCR technique for detection of M. leprae using RLEP primers proved to be specific and sensitive, and qPCR can be used as a complementary test to diagnose leprosy irrespective of the clinical form of disease.

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In situ immunophenotyping of leprosy lesions can improve our understanding of the biology of inflammatory cells during the immune response to Mycobacterium leprae antigens. In the present study, biopsies from 10 healthy controls and 70 leprosy patients were selected, 10 for each of the following conditions: clinical tuberculoid (TT), borderline tuberculoid (BT), borderline borderline (BB), borderline lepromatous (BL), lepromatous (LL), reversal reaction (R1), and erythema nodosum leprosum (R2). Qualitative and quantitative immunohistochemical analyses were performed to detect CD3, CD4, CD8, FoxP3, CD20, CD138, CD1a, CD57, CD15, CD117, CD68, and CD163. In addition, histochemistry was employed to identify eosinophils. The amount of CD3+ and CD4+ T cells was higher in TT than in LL patients. CD8+ T cells were predominant in T lymphocyte infiltrations in the basal layer of the epidermis. The number of FoxP3+ cells was similar among different forms of the disease, but was higher in BL and LL than in R2 individuals. CD20+ lymphocytes were most abundant in TT samples, while CD138+ plasma cells displayed no detectable differences. Epithelioid macrophages from the center of TT and R1 granulomas exhibited the M1 phenotype (CD68+CD163-), whereas those in LL granulomas showed the M2 phenotype (CD68+CD163+). There was a gradual decrease in the amount of CD1a+ cells from the TT towards the LL form of the disease. A significant increase in the number of neutrophils was observed only in R2 samples. All the cells investigated, except eosinophils, participated in the immunopathogenesis of leprosy.

Asunto(s)

RESUMEN

In situ immunophenotyping of leprosy lesions can improve our understanding of the biology of inflammatory cells during the immune response to Mycobacterium leprae antigens. In the present study, biopsies from 10 healthy controls and 70 leprosy patients were selected, 10 for each of the following conditions clinical tuberculoid (TT), borderline tuberculoid (BT), borderline borderline (BB), borderline lepromatous (BL), lepromatous (LL), reversal reaction (R1), and erythema nodosum leprosum (R2). Qualitative and quantitative immunohistochemical analyses were performed to detect CD3, CD4, CD8, FoxP3, CD20, CD138, CD1a, CD57, CD15, CD117, CD68, and CD163. In addition, histochemistry was employed to identify eosinophils. The amount of CD3+ and CD4+ T cells was higher in TT than in LL patients. CD8+ T cells were predominant in T lymphocyte infiltrations in the basal layer of the epidermis. The number of FoxP3+ cells was similar among different forms of the disease, but was higher in BL and LL than in R2 individuals. CD20+ lymphocytes were most abundant in TT samples, while CD138+ plasma cells displayed no detectable differences. Epithelioid macrophages from the center of TT and R1 granulomas exhibited the M1 phenotype (CD68+CD163-), whereas those in LL granulomas showed the M2 phenotype (CD68+CD163+). There was a gradual decrease in the amount of CD1a+ cells from the TT towards the LL form of the disease. A significant increase in the number of neutrophils was observed only in R2 samples. All the cells investigated, except eosinophils, participated in the immunopathogenesis of leprosy.

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