Factors associated with the development of leprosy in contacts: a systematic review and meta-analysis

OBJECTIVE

To investigate the risk factors associated with leprosy in contacts of patients.

METHOD

We carried out a systematic review and meta-analysis by searching the databases MEDLINE, Embase, Cochrane Library, CINAHL, LILACS, Scopus, and Web of Science until September 2019. Four reviewers carried out the selection, analysis, and evaluation of quality of studies. The random effects model was used to calculate the pooled relative risk (RR) and 95% confidence intervals (95% CI) when heterogeneity was greater than 50%.

RESULTS

The search resulted in 2,148 references and included 24 reports. Most of the studies had been conducted in Brazil and India, had a cohort design and included household, neighbors, and social contacts. The risk factors associated with illness due to leprosy in contacts were: illiteracy (RR = 1,48; 95%CI 1,22 - 1,79), living in the same house (RR = 2,41; 95%CI 1,87 - 3,10) of a case of leprosy with high bacillary load (RR = 2.40; 95%CI 1.69 - 3.41), seropositivity to the Mycobacterium leprae PGL-1 (phenolic glycolipid-1) antigen (RR = 3.54; 95%CI 2.21 - 5.67), presence of the bacillus in the bloodstream (RR = 10.61; 95%CI 4.74 - 23.77) and negative Mitsuda reaction (RR = 2,68; 95%CI 1,76 - 4,07). Immunization with BCG (bacillus Calmette-Guérin) vaccine had a protective effect against leprosy.

CONCLUSION

Leprosy in contacts of patients involves social determination, individual susceptibility, and difficulties in access to disease control actions, but modifiable risk factors are the main determinants of illness in this population.

Socioeconomic factors related to leprosy: an integrative literature review

ABSTRACT Objective: To investigate in the literature the relation of socioeconomic factors in the incidence of the disease and other outcomes related to leprosy. Method: Integrative review conducted in Lilacs, Medline, Scopus databases and SciELO online library with studies from 2000 to 2016. Results: 32 studies were included. Only studies that analyzed statistical associations of socioeconomic factors and outcomes related to leprosy were selected. Conclusion: Leprosy is greatly affected by the social context in which the patient is inserted, the chances of exposure to illness are the result of a set of not only individual aspects, but also of contexts or collective conditions. It is imperative for Nursing, as an essential part of the multiprofessional team entrusted with the care and surveillance of the disease, to recognize these factors to predict unfavorable outcomes and to develop new practices capable of reducing inequities.

A baixa escolaridade está associada ao aumento de incapacidades físicas no diagnóstico de hanseníase no Vale do Jequitinhonha

Introdução: a hanseníase é uma doença infecciosa cujo diagnóstico, quando realizado tardiamente, resulta em dano neural e incapacidades físicas que restringem a participação social do indivíduo e contribuem para o estigma e discriminação. Além disso, fatores de risco ambientais, socioeconômicos e individuais podem contribuir para a vulnerabilidade ao adoecimento e evolução para incapacidades físicas. Objetivo: analisar a influência da escolaridade na ocorrência de incapacidades físicas no diagnóstico da hanseníase no Vale do Jequitinhonha, Minas Gerais. Material e Métodos: trata-se de um estudo transversal realizado na população de casos de hanseníase diagnosticados no Vale do Jequitinhonha, no período de 2001 a 2017, a partir de dados obtidos no Sistema de Informação de Agravos de Notificação (SINAN). A variável dependente foi o grau de incapacidade física no diagnóstico da hanseníase e a variável explicativa o nível de escolaridade dos casos. A análise estatística compreendeu a realização dos testes qui-quadrado, coeficiente de correlação de Spearman e odds ratio. Resultados: foram notificados 1.940 casos de hanseníase no Vale do Jequitinhonha com uma taxa média de detecção de 47 casos/100.000 habitantes. Houve uma correlação inversamente proporcional entre as variáveis escolaridade e grau de incapacidade com significância estatística (-0,17; p<0,0001). Indivíduos sem escolaridade tiveram 82% mais chance de apresentarem incapacidades no diagnóstico de hanseníase quando comparados àqueles com nível fundamental (OR = 1,82; p = <0,0001), a chance de incapacidades foi ainda maior na comparação com a escolaridade de nível médio (OR = 4,03; p<0,0001). Conclusão: o aumento no nível de escolaridade dos casos reduziu a chance de ser diagnosticado com alguma incapacidade instalada.

The TLR1 gene is associated with higher protection from leprosy in women

Leprosy is an infectious disease with a complex genetic and immunological background. Polymorphisms in genes that encode cytokines and receptors involved in the immune response, such as the Toll-like receptor 1 (TLR1), may be associated with disease risk. We hypothesized that polymorphisms in innate immunity genes confer susceptibility to leprosy that differs between women and men. In this study, we investigate sex differences in the association between a single nucleotide polymorphism (SNP) in TLR1 and Nucleotide-binding oligomerization domain containing 2 (NOD2) genes and leprosy susceptibility in 256 clinically classified leprosy patients and 233 control subjects in a Brazilian population. Our results showed no association between the SNP rs8057341 in NOD2 and leprosy in this population. However, the heterozygous genotype of the TLR1 SNP (rs4833095) showed a statistically significant association in women (OR = 0.54, P = 0.02). Our findings suggest that the TLR1 polymorphism was associated with an increased protection from leprosy in women.