RESUMO
A case of Mycobacterium leprae rifampin resistance after irregular antileprosy treatments since 1971 is reported. Whole-genome sequencing from four longitudinal samples indicated relapse due to acquired rifampin resistance and not to reinfection with another strain. A putative compensatory mutation in rpoC was also detected. Clinical improvement was achieved using an alternative therapy.
Assuntos
Hanseníase , Mycobacterium leprae , Humanos , Hanseníase/tratamento farmacológico , Mutação , Mycobacterium leprae/genética , Recidiva , Rifampina/farmacologiaRESUMO
INTRODUCTION: Leprosy is a public health problem in Brazil where 31,044 new cases were detected in 2013. Rio Grande do Norte is a small Brazilian state with a rate of leprosy lower than other areas in the same region, for unknown reasons. OBJECTIVES: We present here a review based on the analysis of a database of registered leprosy cases in Rio Grande do Norte state, comparing leprosy's geographic distribution among municipalities with local socio-economic and public health indicators and with historical documents about human migration in this Brazilian region. RESULTS: The current distribution of leprosy in Rio Grande do Norte did not show correlation with socio-economic or public health indicators at the municipal level, but it appears related to economically emerging municipalities 100 years ago, with spread facilitated by railroads and train stations. Drought-related migratory movements which occurred from this state to leprosy endemic areas within the same period may be involved in the introduction of leprosy and with its present distribution within Rio Grande do Norte. CONCLUSIONS: Leprosy may disseminate slowly, over many decades in certain circumstances, such as in small cities with few cases. This is a very unusual situation currently and a unique opportunity for epidemiologic studies of leprosy as an emerging disease.
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Migração Humana , Hanseníase/epidemiologia , Brasil/epidemiologia , Humanos , Hanseníase/transmissão , Saúde Pública , ViagemRESUMO
OBJECTIVE: To evaluate the risk factors related to worsening of physical disabilities after treatment discharge among patients with leprosy administered 12 consecutive monthly doses of multidrug therapy (MDT/WHO). METHODS: Cohort study was carried out at the Leprosy Laboratory in Rio de Janeiro, Brazil. We evaluated patients with multibacillary leprosy treated (MDT/WHO) between 1997 and 2007. The Cox proportional hazards model was used to estimate the relationship between the onset of physical disabilities after release from treatment and epidemiological and clinical characteristics. RESULTS: The total observation time period for the 368 patients was 1 570 person-years (PY), averaging 4.3 years per patient. The overall incidence rate of worsening of disability was 6.5/100 PY. Among those who began treatment with no disability, the incidence rate of physical disability was 4.5/100 PY. Among those who started treatment with Grade 1 or 2 disabilities, the incidence rate of deterioration was 10.5/100 PY. The survival analysis evidenced that when disability grade was 1, the risk was 1.61 (95% CI: 1.02-2.56), when disability was 2, the risk was 2.37 (95% CI 1.35-4.16), and when the number of skin lesions was 15 or more, an HR = 1.97 (95% CI: 1.07-3.63). Patients with neuritis showed a 65% increased risk of worsening of disability (HR = 1.65 [95% CI: 1.08-2.52]). CONCLUSION: Impairment at diagnosis was the main risk factor for neurological worsening after treatment/MDT. Early diagnosis and prompt treatment of reactional episodes remain the main means of preventing physical disabilities.
Assuntos
Avaliação da Deficiência , Progressão da Doença , Hansenostáticos/uso terapêutico , Hanseníase Multibacilar/complicações , Doenças do Sistema Nervoso/etiologia , Adolescente , Adulto , Idoso , Instituições de Assistência Ambulatorial , Brasil , Criança , Pré-Escolar , Estudos de Coortes , Pessoas com Deficiência , Quimioterapia Combinada , Feminino , Humanos , Hansenostáticos/administração & dosagem , Hansenostáticos/efeitos adversos , Hanseníase Multibacilar/tratamento farmacológico , Hanseníase Multibacilar/patologia , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/complicações , Alta do Paciente , Modelos de Riscos Proporcionais , Fatores de Risco , Adulto JovemRESUMO
Contact surveillance is a valuable strategy for controlling leprosy. A dynamic cohort study of leprosy contacts was initiated in 1987 at Oswaldo Cruz Foundation. The objective of this work was to review the data on the major risk factors leading up to the infectious stage of the disease, estimate incidence rates of leprosy in the cohort and characterise the risk factors for the disease among the contacts under surveillance. The incidence rate of leprosy among contacts of leprosy patients was estimated at 0.01694 cases per person-year in the first five years of follow-up. The following factors were associated with acquiring the disease: (i) not receiving the BCG vaccine, (ii) a negative Mitsuda reaction and (iii) contact with a patient with a multibacillary clinical form of leprosy. The contacts of index patients who had high bacilloscopic index scores > 1 were at especially high risk of infection. The following factors were associated with infection, which was defined as a seropositive reaction for anti-phenolic glicolipid-1 IgM: (i) young age (< 20 years), (ii) a low measured Mitsuda reaction (< 5 mm) and (iii) contact with an index patient who had a high bacilloscopic index. BCG vaccination and re-vaccination were shown to be protective among household contacts. The main conclusions of this study indicate an urgent need for additional leprosy control strategies in areas with a high incidence of the disease.
Assuntos
Busca de Comunicante/estatística & dados numéricos , Hanseníase/transmissão , Estudos de Coortes , Características da Família , Humanos , Incidência , Hanseníase/epidemiologia , Hanseníase/prevenção & controle , Modelos Biológicos , Vigilância da População , Fatores de TempoRESUMO
Contact surveillance is an important strategy to ensure effective early diagnosis and control of leprosy; passive detection may not be as efficient because it is directly tied to the ready availability of heath care services and health education campaigns. The aim of this study was to reinforce that contact surveillance is the most effective strategy for the control of leprosy. The analysed data were obtained from a cohort of contacts and cases diagnosed through a national referral service for leprosy. We analysed data from patients diagnosed between 1987-2010 at the Souza Araújo Ambulatory in Rio de Janeiro. Epidemiological characteristics of leprosy cases diagnosed through contact surveillance and characteristics of passively detected index cases were compared using a conditional logistic regression model. Cases diagnosed by contact surveillance were found earlier in the progression of the disease, resulting in less severe clinical presentations, lower levels of initial and final disability grades, lower initial and final bacterial indices and a lower prevalence of disease reaction. In this respect, contact surveillance proved to be an effective tertiary prevention strategy, indicating that active surveillance is especially important in areas of high endemicity, such as Brazil.
Assuntos
Busca de Comunicante/estatística & dados numéricos , Hanseníase/epidemiologia , Vigilância da População , Brasil/epidemiologia , Estudos de Coortes , Feminino , Humanos , Hanseníase/transmissão , Masculino , PrevalênciaRESUMO
OBJECTIVE: To analyze a profile of patients treated at a national leprosy outpatient referral clinic in metropolitan Rio de Janeiro, Brazil, over a period of more than two decades, and the subgroup of nationally registered leprosy cases from the same residential area, as well as all registered cases statewide. METHODS: An observational, descriptive analysis was carried out for patients treated from 1986 to 2007 at the Souza Araújo Outpatient Clinic (Ambulatório Souza Araújo, ASA), a national referral center for the diagnosis and treatment of leprosy at the Oswaldo Cruz Foundation (Fiocruz) that serves clients from the city of Rio de Janeiro and other municipalities in the metropolitan area of Rio de Janeiro State. Demographic and clinical data for the subgroup of leprosy cases registered with Brazil's National Disease Notification System (Sistema Nacional de Informação de Agravos de Notificação, SINAN) between 2001 and 2007 and residing in the same municipalities as the ASA patients, and for all registered cases statewide, were also analyzed. RESULTS: Among the ASA patients, there was a decrease in average family income (from 3.9 to 2.7 times the minimum salary between the periods 1998-2002 and 2003-2007); the proportion of multibacillary (MB) patients (from 52.7% to 46.9%); and the proportion of patients younger than 15 years old (from 12.8% to 8.7%). Among the MB patients, the average initial and final bacilloscopic indices were significantly higher in 2003-2007. Compared with the SINAN cases, more ASA cases involved disability and were younger than 15 years old. CONCLUSIONS: Patients living with leprosy in the metropolitan area of the state of Rio de Janeiro belong to the most deprived social strata and have not benefited from the overall improvement in socioeconomic conditions in Brazil.
Assuntos
Hanseníase/epidemiologia , Adolescente , Instituições de Assistência Ambulatorial , Brasil/epidemiologia , Feminino , Humanos , Masculino , Fatores SocioeconômicosRESUMO
Leprosy household contacts are generally more prone to develop the disease compared to the general population. Previous studies have demonstrated that genes related to the alternative activation (M2) profile in macrophages are associated with the increased bacillary load in multibacillary leprosy patients (MB), and that contacts of MB patients have a higher risk of contracting the disease. In addition, positive serological responses to PGL-1 or LID-1 are associated with a higher risk of disease. We performed a 5-year follow-up of contacts of leprosy patients and evaluated the pattern of gene and protein expression in cells from contacts that developed leprosy during this period. Leprosy household contacts had decreased soluble CD163 and heme oxygenase 1 (HO-1) serum levels when compared with healthy donors and leprosy patients. In contrast, arginase 1 activities were higher in contacts when compared with both healthy donors and leprosy patients. Of the contacts, 33 developed leprosy during the follow-up. Gene expression analysis revealed reduced ARG1 expression in these contacts when compared with contacts that did not develop disease. Arginase activity was a good predictive marker of protection in contacts (sensitivity: 90.0%, specificity: 96.77%) and the association with serology for anti-PGL-1 and anti-LID-1 increased the sensitivity to 100%. Altogether, the data presented here demonstrate a positive role of arginase against leprosy and suggest that the evaluation of arginase activity should be incorporated into leprosy control programs in order to aid in the decision of which contacts should receive chemoprophylaxis.
Assuntos
Hanseníase , Mycobacterium leprae , Anticorpos Antibacterianos , Antígenos de Bactérias , Arginase/genética , Biomarcadores , Ensaio de Imunoadsorção Enzimática , Glicolipídeos , HumanosRESUMO
Reduction in incidence has been associated with the introduction of novel approaches, like chemo/immune-prophylaxis. Incidence determined through follow-up cohort studies can evaluate the implementation of these innovative policies towards control and prevention. We have assessed the incidence in our contacts cohort over past 33 years, considering the effect of demographic and clinical variables. Survival analysis was used to estimate the risk of leprosy. A total of 9024 contacts were evaluated, of which 192 developed leprosy, resulting in an overall incidence of 1.4/1000 person-years. The multivariate analysis showed that the major risk factors were (i) contact from MB index cases and (ii) consanguinity (iii) intra household contact. Lower risk was detected for contacts with BCG scar who were revaccinated. There was a significant decrease in accumulated risk between the 2011-2019 period compared with 1987, probably linked to the improvement in laboratory tools to monitor contacts, thereby providing early diagnosis of contacts at intake and reduction of transmission. Our findings suggest that a combination of contact surveillance and tracing, adequate neurodermatological examination, and availability of molecular tools is highly effective in supporting early diagnosis, while a second dose of the BCG vaccination can exert extra protection.
Assuntos
Hanseníase/epidemiologia , Adolescente , Adulto , Vacina BCG/administração & dosagem , Criança , Estudos de Coortes , Busca de Comunicante , Feminino , Humanos , Incidência , Hanseníase/prevenção & controle , Hanseníase/transmissão , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Análise de Sobrevida , Adulto JovemRESUMO
Household contacts (HHC) of leprosy patients exhibit high-risk of developing leprosy and contact tracing is helpful for early diagnosis. From 2011 to 2018,2,437 HHC were examined in a clinic in Rio de Janeiro, Brazil and 16S qPCR was used for diagnosis and monitoring of contacts. Fifty-four HHCs were clinically diagnosed with leprosy at intake. Another 25 exhibited leprosy-like skin lesions at intake, 8 of which were confirmed as having leprosy (50% of which were qPCR positive) and 17 of which were diagnosed with other skin diseases (6% qPCR positive). In skin biopsies, qPCR presented a sensitivity of 0.50 and specificity of 0.94. Furthermore, 955 healthy HHCs were followed-up for at least 3 years and skin scrapings were collected from earlobes for qPCR detection. Positive qPCR indicated a non-significant relative risk of 2.52 of developing the disease. During follow-up, those who progressed towards leprosy exhibited 20% qPCR positivity, compared to 9% of those who remained healthy. Disease-free survival rates indicated that age had a significant impact on disease progression, where patients over 60 had a greater chance of developing leprosy [HR = 32.4 (3.6-290.3)]. Contact tracing combined with qPCR may assist in early diagnosis and age is a risk factor for leprosy progression.
Assuntos
Busca de Comunicante/métodos , DNA Bacteriano/análise , DNA Ribossômico/análise , Características da Família , Hanseníase/diagnóstico , Mycobacterium leprae/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adolescente , Adulto , Brasil/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Humanos , Lactente , Hanseníase/epidemiologia , Hanseníase/genética , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Mycobacterium leprae/genética , Fatores de Tempo , Adulto JovemRESUMO
BACKGROUND: The annual new-case detection rate for leprosy, while generally stable over the last decade, shows that transmission rates have remained stagnant despite the successful worldwide administration of multidrug therapy since the 1980s. As such, novel control strategies are urgently needed. Focusing on managing leprosy patient contacts, the most susceptible to contracting the disease, has been seen as a potential strategy in limiting the spread of leprosy as shown by a number of recent epidemiological studies. Immunoprophylaxis with Bacillus Calmette-Guérin (BCG) has been seen as an effective preventive measure due to its ability to stimulate the development of cellular immunity which is essential in controlling the disease, especially in its multibacillary (MB) forms. The association of immunoprophylaxis with chemoprophylaxis in a single dose of rifampicin has been shown to be a promising preventive strategy, although a variety of studies have found instances of early case detection just a few months after BCG vaccination. METHODS/DESIGN: The present study is a phase IV chemoprophylactic clinical trial consisting of administration of a single dose of rifampicin in MB leprosy patient contacts under care at the Souza Araújo Outpatient Clinic/FIOCRUZ as part of a randomized (2:1), double-blind, placebo-controlled study. It is comprised of two groups: 1) rifampicin + BCG; and 2) placebo + BCG. DISCUSSION: The aim is to evaluate whether the use of chemoprophylaxis with a single dose of rifampicin in MB leprosy patient contacts prior to the BCG vaccine would be able to prevent the onset of leprosy in those cases that may occur just a few months after vaccination. Contact subclinical infections (polymerase chain reaction) and the immunological parameters (anti-PGL-1, anti-LID-1, and IFN-γ) will be evaluated and the results will be compared after 12 months of follow-up. TRIAL REGISTRATION: The Brazilian Registry of Clinical Trials (ReBEC), RBR-69QK5P . Retrospectively registered on 1 June 2017.
Assuntos
Vacina BCG/administração & dosagem , Busca de Comunicante , Hansenostáticos/administração & dosagem , Hanseníase Multibacilar/prevenção & controle , Rifampina/administração & dosagem , Adolescente , Adulto , Idoso , Vacina BCG/efeitos adversos , Brasil , Criança , Pré-Escolar , Ensaios Clínicos Fase IV como Assunto , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Lactente , Hansenostáticos/efeitos adversos , Hanseníase Multibacilar/imunologia , Hanseníase Multibacilar/microbiologia , Hanseníase Multibacilar/transmissão , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Rifampina/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Vacinação , Adulto JovemRESUMO
There are no reliable means for detecting subclinical mycobacterial infections. The recent sequencing of several mycobacterial genomes has now afforded new opportunities for the development of pathogen-specific diagnostic tests, critical in the context of leprosy and tuberculosis control. In the present study, we applied a multi-parametric flow cytometric analysis that allowed the investigation of T-cell functions in order to define immunological markers that measure previous exposure to mycobacteria. We compared the in vivo response to PPD, the gold standard skin test reagent for measuring previous exposure to Mycobacterium tuberculosis, with in vitro parameters of leukocyte activation in five PPD positive and five PPD negative healthy volunteers. PPD-stimulated peripheral leukocytes expressing CD4, CD69, cutaneous lymphocyte-associated antigen (CLA) and intracellular IFN-gamma were enumerated in whole blood and compared with the size of in vivo PPD-induced induration and IFN-gamma production levels as measured by ELISA in supernatants of PPD-stimulated peripheral blood mononuclear cells. The reactivity to the tuberculin skin test (TST) was associated with markedly increased frequencies of PPD-responsive activated (CD69+) and IFN-gamma-producing CD4+T cells. Detection of PPD-specific IFN-gamma producing leukocytes was restricted to CD4+T cells and a subset of these cells was shown to express the skin homing molecule CLA. Multiple linear regression modeling of responses to PPD showed the highest association between skin test indurations and frequencies of PPD-responsive IFN-gamma-producing CD4+CD69+ T cells. Our data show that the in vitro enumeration of antigen-specific IFN-gamma-producing CD4+ T cells can provide an alternative to the in vivo tuberculin test for the detection of latent Mycobacterium tuberculosis infection. Moreover, the measurement of these immunological parameters can be useful for the screening of new specific antigens defined by the genome sequence allowing selection of the best candidates for new diagnostics (including new skin tests), and vaccines for leprosy and tuberculosis.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Interferon gama/metabolismo , Teste Tuberculínico , Adulto , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Contagem de Linfócito CD4 , Feminino , Humanos , Lectinas Tipo C , Ativação Linfocitária , Masculino , TuberculinaRESUMO
A comparative study was performed on the initial and final bacillary indexes of 213 multibacillary leprosy patients who received 12 doses (Group 1: 128 patients) or 24 doses (Group 2: 85 patients) of multidrug therapy (MDT/WHO) to measure the effectiveness of the two regimens. All patients were evaluated at treatment baseline, 12 months, and 24 months. The reduction in bacillary levels and mean bacillary indexes at 24 months was similar in the two groups. No statistical difference in reaction rates was observed between the two treatment regimens.
Assuntos
Hansenostáticos/administração & dosagem , Hanseníase Virchowiana/tratamento farmacológico , Adulto , Protocolos Clínicos , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Hanseníase Virchowiana/microbiologia , Modelos Lineares , Masculino , Fatores de Tempo , Resultado do TratamentoRESUMO
Household contacts of multibacillary leprosy patients (HCMB) constitute the group of individuals at the highest risk of developing leprosy. Early diagnosis and treatment of their index cases combined with Bacille Calmette-Guerin (BCG) immunization remain important strategies adopted in Brazil to prevent HCMB from evolving into active disease. In the present study, we assessed the impact of these measures on the immune response to Mycobacterium leprae in HCMB. Peripheral blood mononuclear cells (PBMC) from HCMB (n = 16) were obtained at the beginning of leprosy index case treatment (T0). At this time point, contacts were vaccinated (n = 13) or not (n = 3) in accordance with their infancy history of BCG vaccination and PBMCs were recollected at least 6 months later (T1). As expected, a significant increase in memory CD4 and CD8 T cell frequencies responsive to M. leprae whole-cell sonicate was observed in most contacts. Of note, higher frequencies of CD4+ T cells that recognize M. leprae specific epitopes were also detected. Moreover, increased production of the inflammatory mediators IL1-ß, IL-6, IL-17, TNF, IFN-γ, MIP1-ß, and MCP-1 was found at T1. Interestingly, the increment in these parameters was observed even in those contacts that were not BCG vaccinated at T0. This result reinforces the hypothesis that the continuous exposure of HCMB to live M. leprae down regulates the specific cellular immune response against the pathogen. Moreover, our data suggest that BCG vaccination of HCMB induces activation of T cell clones, likely through "trained immunity", that recognize M. leprae specific antigens not shared with BCG as an additional protective mechanism besides the expected boost in cell-mediated immunity by BCG homologues of M. leprae antigens.
Assuntos
Antígenos de Bactérias/imunologia , Vacina BCG/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Imunidade Celular , Hanseníase Multibacilar/imunologia , Adulto , Anticorpos Antibacterianos/sangue , Brasil , Linfócitos T CD8-Positivos/imunologia , Citocinas/metabolismo , Epitopos de Linfócito T/imunologia , Características da Família , Feminino , Humanos , Imunoglobulina M/sangue , Hanseníase Multibacilar/prevenção & controle , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae , Estudos Prospectivos , Adulto JovemRESUMO
OBJECTIVE: We evaluated the profile of patients referred to the Fiocruz Outpatient Clinic, a reference center for the diagnosis and treatment of leprosy in Rio de Janeiro, RJ, and analyzed the origins and outcomes of these referrals. METHODS: This is an observational retrospective study based on information collected from the Leprosy Laboratory database at Fiocruz, Rio de Janeiro, RJ, Brazil. A total of 1,845 suspected leprosy cases examined at the reference center between 2010 and 2014 were included. The originating health service referrals and diagnostic outcomes were analyzed as well as the clinical and epidemiological data of patients diagnosed with leprosy. RESULT: Our data show that the profile of the patients treated at the Clinic has changed in recent years. There was an increase in both the proportion of patients with other skin diseases and those who had visited only one health service prior to our Clinic. Among the total 1,845 cases analyzed, the outcomes of 1,380 were linked to other diseases and, in 74% of these cases, a biopsy was not necessary to reach a diagnostic conclusion. A decrease in new leprosy case detection among our patients was also observed. Yet, among the leprosy patients, 40% had some degree of disability at diagnosis. CONCLUSION: The results of the present study demonstrated the importance of referral centers in support of basic health services within the decentralization strategy. But, the success of the program depends on the advent of new developmental tools to augment diagnostic accuracy for leprosy. However, it should be emphasized that for new diagnostic methods to be developed, a greater commitment on the part of the health care system regarding research is urgently needed.
Assuntos
Hanseníase/terapia , Instituições de Assistência Ambulatorial/organização & administração , Brasil/epidemiologia , Humanos , Hanseníase/diagnóstico , Hanseníase/epidemiologia , Saúde Pública , Encaminhamento e Consulta , Estudos RetrospectivosRESUMO
The clinical diagnosis of pure neural leprosy (PNL) remains a public health care problem mainly because skin lesions-the cardinal features of leprosy-are always absent.Moreover, the identification of the leprosy bacillus is not easily achieved even when a nerve biopsy can be performed. In an attempt to reach a reliable PNL diagnosis in patients referred to our Leprosy Outpatient Clinic, this study employed a variety of criteria. The nerve biopsies performed on the 67 individuals whose clinical, neurological, and electrophysiological examination findings strongly suggested peripheral neuropathy were submitted to M. leprae identification via a polymerase chain reaction (PCR). Mononeuropathy multiplex was the most frequent clinical and electrophysiological pattern of nerve dysfunction, while sensory impairment occurred in 89% of all cases and motor dysfunction in 81%. Axonal neuropathy was the predominant electrophysiological finding, while the histopathological nerve study showed epithelioid granuloma in 14% of the patients, acid fast bacilli in 16%, and nonspecific inflammatory infiltrate and/or fibrosis in 39%. PCR for M. leprae was positive in 47% of the nerve biopsy samples (n=23). PCR, in conjunction with clinical and neurological examination results, can be a powerful tool in attempting to identify and confirm a PNL diagnosis.
Assuntos
Hanseníase Tuberculoide/diagnóstico , Hanseníase Tuberculoide/microbiologia , Mycobacterium leprae , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Nervos Periféricos/microbiologia , Nervos Periféricos/patologiaRESUMO
A broad variety of factors have been associated with leprosy among contacts, including socioeconomic, epidemiological, and genetic characteristics. Data from 7,174 contacts of leprosy patients from a leprosy outpatient clinic in Rio de Janeiro, Brazil, 1987-2010, were analyzed to investigate the effects of kinship, individual, and contextual factors on leprosy. Multivariate analyses were performed using a robust estimation method. In the prevalence analysis, close kinship (sibling OR = 2.75, offspring OR = 2.00, and other relatives OR = 1.70), socioeconomic factors, and the duration of exposure to the bacillus were associated to leprosy. In the incidence analysis, significant risks were found for all categories of kinship (parents RR = 10.93, spouse, boyfriend/girlfriend, and bride/groom RR = 7.53, sibling RR = 7.03, offspring RR = 5.34, and other relatives RR = 3.71). Once the treatment of the index case was initiated, other factors lost their significance, and the index case bacteriological index and BCG (Bacillus Calmette-Guérin vaccine) protection had a greater impact. Our findings suggested that both genetic susceptibility and physical exposure play an important role in the epidemiology of leprosy, but it was not possible establishing the role of genetic factor. Analyses of other factors related to the genotype of individuals, such as genetic polymorphisms, are needed.
RESUMO
BACKGROUND: Contacts of leprosy patients are at increased risk of developing leprosy and need to be targeted for early diagnosis. Seropositivity to the phenolic glycolipid I (PGL-I) antigen of Mycobacterium leprae has been used to identify contacts who have an increased risk of developing leprosy. In the present study, we studied the effect of seropositivity in patient contacts, on the risk of developing leprosy, stratified by Bacille Calmette Guerin (BCG) vaccination after index case diagnosis. METHODOLOGY/PRINCIPAL FINDINGS: Leprosy contacts were examined as part of the surveillance programme of the Oswaldo Cruz Institute Leprosy Outpatient Clinic in Rio de Janeiro. Demographic, social, epidemiological and clinical data were collected. The presence of IgM antibodies to PGL-I in sera and BCG vaccination status at the time of index case diagnosis were evaluated in 2,135 contacts. During follow-up, 60 (2.8%; 60/2,135) leprosy cases were diagnosed: 41 among the 1,793 PGL-I-negative contacts and 19 among the 342 PGL-I-positive contacts. Among PGL-I-positive contacts, BCG vaccination after index case diagnosis increased the adjusted rate of developing clinical manifestations of leprosy (Adjusted Rate Ratio (aRR)â=â4.1; 95% CI: 1.8-8.2) compared with the PGL-I-positive unvaccinated contacts (aRRâ=â3.2; 95% CI: 1.2-8.1). The incidence density was highest during the first year of follow-up for the PGL-I-positive vaccinated contacts. However, all of those contacts developed PB leprosy, whereas most MB cases (4/6) occurred in PGL-I-positive unvaccinated contacts. CONCLUSION: Contact examination combined with PGL-I testing and BCG vaccination remain important strategies for leprosy control. The finding that rates of leprosy cases were highest among seropositive contacts justifies targeting this specific group for close monitoring. Furthermore, it is recommended that PGL-I-positive contacts and contacts with a high familial bacteriological index, regardless of serological response, should be monitored. This group could be considered as a target for chemoprophylaxis.
Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Vacina BCG/imunologia , Glicolipídeos/imunologia , Hanseníase/epidemiologia , Hanseníase/imunologia , Mycobacterium leprae/patogenicidade , Adolescente , Adulto , Idoso , Vacina BCG/administração & dosagem , Criança , Pré-Escolar , Estudos de Coortes , Humanos , Imunoglobulina M/sangue , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/imunologia , Medição de Risco , Adulto JovemRESUMO
UNLABELLED: The scope of this study was to compare epidemiological data on leprosy patients living in two cities with different socioeconomic and endemic profiles that were monitored in a single center of reference. A descriptive study was made of data from patients in the Souza Araújo Outpatient facility treated in the period 1986-2008, who were resident in the cities of Rio de Janeiro = 1353) and Duque de Caxias (n = 336). RESULTS: Among patients from Duque de Caxias, in comparison with patients from Rio de Janeiro, there was a higher proportion of cases: below the age of 15 years, multibacillary, higher initial bacilloscopic index (BI) and cases detected through surveillance of contacts. Patients in Duque de Caxias had lower average incomes and education levels. There were no statistically significant differences regarding gender, disability level, reaction in the diagnosis, final BI, bandonment and regularity of treatment. The differences found between the patients monitored in a single center of reference, could be partly related to contextual differences between the municipalities. On the other hand, it was observed that the provision of treatment and monitoring can minimize the effect of different contextual factors on health outcomes.