; and the Dapsone Hypersensitivity Syndrome Prevention Working Group IMPORTANCE Dapsone hypersensitivity syndrome (DHS) is the most serious adverse reaction associated with dapsone administration and one of the major causes of death in patients with leprosy, whose standard treatment includes multidrug therapy (MDT) with dapsone, rifampicin, and clofazimine. Although the HLA-B*13:01 polymorphism has been identified as the genetic determinant of DHS in the Chinese population, no studies to date have been done to evaluate whether prospective HLA-B*13:01 screening could prevent DHS by identifying patients who should not receive dapsone. OBJECTIVE To evaluate the clinical use of prospective HLA-B*13:01 screening for reduction of the incidence of DHS by excluding dapsone from the treatment for patients with HLA-B*13:01-positive leprosy. DESIGN, SETTING, AND PARTICIPANTS A prospective cohort study was conducted from February 15, 2015, to April 30, 2018, in 21 provinces throughout China. A total of 1539 patients with newly diagnosed leprosy were enrolled who had not received dapsone previously. After excluding patients who had a history of allergy to sulfones or glucose-6-phosphate dehydrogenase deficiency, 1512 individuals underwent HLA-B*13:01 genotyping. All of the patients were followed up weekly for the first 8 weeks after treatment to monitor for adverse events. EXPOSURES Patients who were HLA-B*13:01 carriers were instructed to eliminate dapsone from their treatment regimens, and noncarrier patients received standard MDT. MAIN OUTCOMES AND MEASURES The primary outcome was the incidence of DHS. The historical incidence rate of DHS (1.0%) was used as a control. RESULTS Among 1512 patients (1026 [67.9%] men, 486 [32.1%] women; mean [SD] age, 43.1 [16.2] years), 261 (17.3%) were identified as carriers of the HLA-B*13:01 allele. A total of 714 adverse events in 384 patients were observed during the follow-up period. Dapsone hypersensitivity syndrome did not develop in any of the 1251 patients who were HLA-B*13:01-negative who received dapsone, while approximately 13 patients would be expected to experience DHS, based on the historical incidence rate of 1.0% per year (P = 2.05 × 10 −5). No significant correlation was found between other adverse events, including dermatologic or other events, and HLA-B*13:01 status. CONCLUSIONS AND RELEVANCE Prospective HLA-B*13:01 screening and subsequent elimination of dapsone from MDT for patients with HLA-B*13:01-positive leprosy may significantly reduce the incidence of DHS in the Chinese population.

Background This epidemiological study aimed to analyse both the distribution and characteristics of leprosy in an endemic province in Northwest China. Methods The medical records of leprosy patients in the province of Shaanxi, China, from 1998 to 2018 were collected from the Chinese Leprosy Management Information System (LEPMIS). Epidemiological variables were analysed in this study. Results A total of 477 new cases were diagnosed between 1998 and 2018 in this region. The average annual detection rate was 0.070/100,000 population, and the average annual prevalence was 0.305/100,000 population. The mean age of the newly diagnosed patients was 46.7 years, and the ratio of males to females was 2.5:1. There were 399 cases (83.6%) of multibacillary (MB) leprosy. One hundred forty-eight patients (31.0%) had grade 2 disability. The mean diagnosis time for new cases was 62.0 months. Conclusion This epidemiological study showed that the characteristics of newly diagnosed leprosy cases in our province were a long time to diagnosis and a high rate of deformity, indicating the need for actions focusing on early diagnosis and treatment and strengthening the detection of leprosy in low-prevalence areas.

Background: This epidemiological study aimed to analyse both the distribution and characteristics of leprosy in an endemic province in Northwest China.Methods: The medical records of leprosy patients in the province of Shaanxi, China, from 1998-2018 were collected from the Chinese Leprosy Management Information System (LEPMIS). Epidemiological variables were analysed in this study.Results: A total of 477 new cases were diagnosed between 1998 and 2018 in this region. The average annual detection rate was 0.070/100,000 population, and the average annual prevalence was 0.305/100,000 population. The mean age of the newly diagnosed patients was 46.7 years, and the ratio of males to females was 2.5:1. There were 399 cases (83.6%) of multibacillary (MB) leprosy. One hundred forty-eight patients (31.0%) had grade 2 disability. The mean diagnosis time for new cases was 62.0 months.Conclusion: This epidemiological study showed that the characteristics of newly diagnosed leprosy cases in our province were a long time to diagnosis and a high rate of deformity, indicating the need for actions focusing on early diagnosis and treatment and strengthening the detection of leprosy in low-prevalence areas.

Background: Objectives: To analyze the sociodemographic and clinical factors associated with multi-bacillary(MB) leprosy in elimination planning areas in Northwest China.Design: Retrospective observational study.Setting: Three specialized hospitals were included.Participants : The medical records of leprosy in Shaanxi Province from 2004 to 2020 were collected from the leprosy management information system (LEPMIS).Primary and secondary outcome measures: The basic situation of leprosy treatment and follow-up were investigated.Results : 305 new cases of leprosy were included in the study. 272 cases (89.18%) were MB leprosy, and 33 (10.82%) were pauci-bacillary (PB) leprosy. Male patients were more likely to have neurological injury ( P <0.001; OR:0.35; 95%CI:0.194-0.630). Patients over 60 years old were more likely to have leprosy deformity ( P <0.001; OR:0.113; 95%CI:0.027-0.478) and nerve injury ( P =0.035; OR:0.333; 95%CI:0.115-0.965). Patients with marriage histories were more likely to have leprosy deformities ( P =0.018; OR:0.842; 95%CI: 0.718-0.987). Patients with passive detection had a lower probability of leprosy reaction ( P =0.011; OR:4.268; 95%CI:1.276-14.272); Patients with nerve damage, positive skin smear test or level I or level II disability were more likely to be classified as MB leprosy.Conclusions : MB leprosy is related to social and demographic factors (with or without marriage history, age at diagnosis, discovery mode) and clinical factors (such as the number of skin lesions and nerve lesions).