Leprosy and cutaneous leishmaniasis affecting the same individuals: A retrospective cohort analysis in a hyperendemic area in Brazil

PLoS Negl Trop Dis. 2021 Dec 13;15(12):e0010035. doi: 10.1371/journal.pntd.0010035. eCollection 2021 Dec.

Abstract

Background: Leprosy and cutaneous leishmaniasis (CL) are neglected tropical diseases (NTDs) affecting the skin. Their control is challenging but the integration of skin NTDs control programs is recommended to improve timely detection and treatment. However, little is known about the occurrence of leprosy and CL in the same individuals, and what are the characteristics of such patients. This study aimed to identify and characterize patients diagnosed with both leprosy and CL (i.e., outcome) in the hyperendemic state of Mato Grosso, Brazil. Also, we investigated the demographic risk factors associated with the period between the diagnosis of both diseases.

Methodology/principal findings: A retrospective cohort study was conducted with patients diagnosed between 2008 and 2017. From the leprosy (n = 28,204) and CL (n = 24,771) databases of the national reporting system, 414 (0.8%; 414/52,561) patients presenting both diseases were identified through a probabilistic linkage procedure. This observed number was much higher than the number of patients that would be expected by chance alone (n = 22). The spatial distribution of patients presenting the outcome was concentrated in the North and Northeast mesoregions of the state. Through survival analysis, we detected that the probability of a patient developing both diseases increased over time from 0.2% in the first year to 1.0% within seven years. Further, using a Cox model we identified male sex (HR: 2.3; 95% CI: 1.7-2.9) and low schooling level (HR: 1.5; 95% CI: 1.2-1.9) as positively associated with the outcome. Furthermore, the hazard of developing the outcome was higher among individuals aged 40-55 years.

Conclusions/significance: Leprosy and CL are affecting the same individuals in the area. Integration of control policies for both diseases will help to efficiently cover such patients. Measures should be focused on timely diagnosis by following-up patients diagnosed with CL, active case detection, and training of health professionals.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Brazil / epidemiology
  • Child
  • Child, Preschool
  • Coinfection / diagnosis
  • Coinfection / epidemiology*
  • Endemic Diseases
  • Female
  • Humans
  • Leishmaniasis, Cutaneous / diagnosis
  • Leishmaniasis, Cutaneous / epidemiology*
  • Leprosy / diagnosis
  • Leprosy / epidemiology*
  • Male
  • Middle Aged
  • Proportional Hazards Models
  • Retrospective Studies
  • Risk Factors
  • Young Adult

Grants and funding

This work was supported by the Brazilian National Council for Scientific and Technological Development (CNPq) - https://www.gov.br/cnpq/pt-br - process number 421138/2018-1. J.G.G.L. is grateful for a research grant from the Coordination for the Improvement of Higher Education Personnel (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - https://www.gov.br/capes/ - finance code 001, grant 88881.362275/2019-01). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.