Avaliação de quimera antigênica utilizando urina para o diagnóstico da Hanseníase

Abstract

Leprosy is a chronic infectious disease that causes neuropathy from variable degrees. The disease can cause physical disability and functional loss. Although significant progress has been made in controlling the disease, challenges remain, particularly regarding late diagnosis. Less expensive, easy-to-perform tests that are accessible in poorer regions could contribute to controlling better the disease. This study aimed to evaluate patients urine by Indirect ELISA as a biological sample for laboratory diagnosis of leprosy, by using a recombinant chimeric protein previously evaluated using patient serum. Paired serum and urine samples were collected from 310 individuals: healthy individuals without comorbidities (n=55), paucibacillary patients (n=25), multibacillary patients (n=35), contacts of paucibacillary patients (n=30), contacts of multibacillary patients (n=35), and patients with other infectious diseases (n=130). Four synthetic peptides, which were used for the construction of the chimera, showed promising preliminary results with the use of a smaller sample panel, mainly in the detection of multibacillary cases. The use of the recombinant chimera showed sensitivity and specificity values of 100% to differentiate the patients group from those of healthy individuals and patients with other infectious diseases, with positive predictive values (PPV) and negative predictive values (NPV) both of 100%. Using serum; sensitivity and specificity to differentiate leprosy patients from their contacts was 94.2% and 100%, respectively. Using urine; values were 97.0% and 100%, respectively. In addition, NPV was 97% in urine and 93.3% in serum. In conclusion, preliminary data suggest that urine from leprosy patients presented slightly better sensitivity and NPV values compared to the use of serum, indicating that this less invasive biological analyte could be considered in future studies for use in diagnostic tools for detecting paucibacillary and multibacillary clinical forms of the disease.