Factors associated with seropositivity for APGL-Iamong household contacts of leprosy patients

Abstract: INTRODUCTION: Leprosy is mainly transmitted among family members who share genetic and ambient factors. The clinical form of leprosy in the index case and kinship could be risk factors for leprosy transmission. High antibody levels in household contacts (HC) in the absence of neural or skin lesions may characterize latent infection. This study aimed to evaluate the association between seropositivity for anti-phenolic glycolipid-I immunoglobulin M antibodies (APGL-I) in HC and the clinical classification of the index case and to analyze the association between APGL-I positivity with other factors such as age, kinship, and gender. METHODS: We performed a survey among 320 HC of 120 leprosy patients who were evaluated and followed-up in a leprosy outpatient clinic of a university hospital. All HC underwent complete skin examination, peripheral nerve palpation, skin sensory tests, and serologic tests for the detection and quantification of APGL-I. RESULTS: The overall seropositivity rate was 20%, and was greatly affected by kinship. APGL-I seropositivity was higher in siblings (41%), followed by parents (28%), spouses (26%), other (19%), and offspring (14%). Independent risk factors for seropositivity were being siblings (OR 3.3) and being a HC of an index case with indeterminate leprosy (OR 5.3). APGL-I seropositivity was associated with index cases with a bacillary index of 4 (88%; p

摘要：引言：麻风病主要在共享遗传与环境因素的家庭成员之间传播。指示病例（index case）的麻风病临床分型及亲属关系，可能是麻风病传播的危险因素。家庭接触者（household contacts，HC）在无神经或皮肤损害的情况下出现高抗体水平，可提示潜伏感染。本研究旨在评估家庭接触者的抗酚糖脂-I免疫球蛋白M抗体（anti-phenolic glycolipid-I immunoglobulin M antibodies，APGL-I）血清学阳性与指示病例临床分型之间的关联，并分析APGL-I阳性与年龄、亲属关系、性别等其他因素的相关性。方法：本研究对某大学医院麻风病门诊随访评估的120例麻风病患者的320名家庭接触者开展调查。所有家庭接触者均接受全面皮肤检查、周围神经触诊、皮肤感觉测试，以及用于APGL-I检测与定量的血清学检测。结果：总体血清学阳性率为20%，且受亲属关系影响显著。APGL-I血清学阳性率在兄弟姐妹中最高（41%），其次为父母（28%）、配偶（26%）、其他亲属（19%）及子女（14%）。血清学阳性的独立危险因素为兄弟姐妹关系（比值比OR=3.3）以及指示病例为未定类麻风（OR=5.3）。APGL-I血清学阳性与杆菌指数为4的指示病例相关（88%；P