Antimicrobial resistance among leprosy patients in Brazil: real-world data based on the National Surveillance plan

Brazil ranks second among countries for new cases and first for relapse cases of leprosy worldwide. The Mycobacterium leprae Resistance Surveillance Plan was established. We aimed to present the results of a 2-year follow-up of the National Surveillance Plan in Brazil. A cross-sectional study of leprosy cases was performed to investigate antimicrobial resistance (AMR) in Brazil from October 2018 to September 2020. Molecular screening targeting genes related to dapsone (folP1), rifampin (rpoB), and ofloxacin resistance (gyrA) was performed. During the referral period, 63,520 active leprosy patients were registered in Brazil, and 1,183 fulfilled the inclusion criteria for molecular AMR investigation. In total, only 16 (1.4%) patients had genetic polymorphisms associated with AMR. Of these, 8 (50%) had cases of leprosy relapse, 7 (43.8%) had cases of suspected therapeutic failure with standard treatment, and 1 (6.2%) was a case of new leprosy presentation. M. leprae strains with AMR-associated mutations were found for all three genes screened. Isolates from two patients showed simultaneous resistance to dapsone and rifampin, indicating multidrug resistance (MDR). No significant relation ship between clinical variables and the presence of AMR was identified. Our study revealed a low frequency of AMR in Brazil. Isolates were resistant mainly to dapsone, and a very low number of isolates were resistant to rifampin, the main bactericidal agent for leprosy, or presented MDR, reinforcing the importance of the standard World Health Organization multidrug therapy. The greater frequency of AMR among relapsed patients supports the need to constantly monitor this group

Synthesis and evaluation of novel dapsone-thalidomide hybrids for the treatment of type 2 leprosy reactions.

We synthesized a series of novel dapsone-thalidomide hybrids (3a-i) by molecular hybridization and evaluated their potential for the treatment of type 2 leprosy reactions. All of the compounds had analgesic properties. Compounds 3c and 3h were the most active antinociceptive compounds and reduced acetic acid-induced abdominal constrictions by 49.8% and 39.1%, respectively. The hybrid compounds also reduced tumor necrosis factor-α levels in lipopolysaccharide-stimulated L929 cells. Compound 3i was the most active compound; at concentrations of 15.62 and 125 µM, compound 3i decreased tumor necrosis factor-α levels by 86.33% and 87.80%, respectively. In nude mice infected with Mycobacterium leprae in vivo, compound 3i did not reduce the number of bacilli compared with controls. Compound 3i did not have mutagenic effects in Salmonella typhimurium strains TA100 and TA102, with or without metabolic activation (S9 mixture). Our results indicate that compound 3i is a novel lead compound for the treatment of type 2 leprosy reactions.

The effect of iron supplementation in the diet of Dasypus novemcinctus (Linnaeus, 1758) armadillos in captivity / O efeito da suplementação com ferro na dieta de tatus Dasypus novemcinctus (Linnaeus, 1758) em cativeiro

Armadillos of the species Dasypus novemcinctus have been used as an experimental model of leprosy. Besides non-human primates, they are the only species naturally infected with Mycobacterium leprae and when experimentally inoculated, reproduce the lepromatous form of the disease producing large quantities of bacilli. This species has been maintained in captivity by numerous researchers and specific housing and feeding requirements have been developed to guarantee their survival during long experimental periods. In the "Lauro de Souza Lima" Institute, armadillos receive dog food, ground beef, boiled eggs and vitamin C. However, despite the balanced diet, anemia has been observed in some captive animals, especially in armadillos inoculated with M. leprae in advanced stages of infection. Thus, the objective of the present study was to evaluate the effect of iron sulfate supplementation in the feed provided for armadillos, both inoculated and non-inoculated with M. leprae, by means of the evaluation of their hematological profile. Fourteen armadillos received 10 mg/animal of iron sulfate (Hematofer®) diluted in sterile water mixed with their daily feed for 50 days. Hemograms and serum iron dosages for each armadillo were performed before and after supplementation. The hematocrit values increased significantly after iron supplementation, both in armadillos inoculated and non-inoculated with M. leprae. It is possible that the amount of iron in the feed is insufficient for the formation of hemoglobin, leading to microcytic anemia. Dietary supplementation with iron sulfate reversed this state, showing the importance of understanding the metabolism of exotic species for their maintenance in captivity, and thus ensuring their well-being.

O tatu da espécie Dasypus novemcinctus tem sido utilizado como modelo experimental para a hanseníase. Eles são a única espécie, além de primatas não humanos, que se apresentam naturalmente infectados pelo Mycobacterium leprae. Estes tatus, quando experimentalmente inoculados, reproduzem a forma virchoviana da hanseníase produzindo grandes quantidades de bacilos. Esta espécie tem sido mantida em cativeiro por vários pesquisadores, no entanto, alguns cuidados são necessários para garantir a sobrevivência destes por longos períodos experimentais, tais como alojamento e alimentação. No Instituto Lauro de Souza Lima, os animais em cativeiro recebem ração canina, carne bovina, ovos cozidos e vitamina C, mesmo assim, tem-se observado o desenvolvimento de quadros de anemia nestes animais, principalmente nos inoculados com o M. leprae, em estados avançados da infecção. Sendo assim, o objetivo deste estudo foi avaliar o efeito da suplementação com sulfato ferroso na alimentação fornecida aos tatus, inoculados e não inoculados com M. leprae, por meio de avaliação de seu perfil hematológico. Foram utilizados 14 animais que receberam 10 mg/animal de sulfato ferroso (Hematofer®) diluídos em água estéril e misturados diariamente à ração por 50 dias. Foram feitos hemograma e dosagem de ferro sérico de cada animal antes e após a suplementação. Os valores de hematócrito aumentaram significativamente após a suplementação, tanto nos animais inoculados como nos não inoculados com M. leprae. É possível que a quantidade de ferro na alimentação seja insuficiente para a formação da hemoglobina, levando a um quadro de anemia microcítica. A suplementação da dieta com sulfato ferroso reverteu este quadro, mostrando a importância de se conhecer o metabolismo de espécies exóticas para manutenção destas em cativeiro, assegurando seu bem estar.