Close household contact with multibacillary leprosy is the primary risk factor for disease transmission. Therefore, early detection of leprosy is crucial for disrupting the transmission chain. The primary objective of this study was to evaluate the diagnostic accuracy of the multiplex XGEN MASTER LEPRAE kit (XGEN) and the point-of-care Bioclin FAST ML FLOW Hanseníase test (PoC-ML-FLOW) among household contacts (HHCs) of leprosy index cases in midwestern Brazil.
We included HHCs of leprosy index cases. After the application of a composite reference standard comprising clinical and laboratory examinations, HHCs were divided into patients with leprosy and controls. The diagnostic accuracy was evaluated using the XGEN and PoC-ML-FLOW.
We included 314 HHCs. Twenty-two HHCs (7%) were diagnosed with leprosy. The PoC-ML-FLOW demonstrated a sensitivity of 45.45% and a specificity of 74.91%. The XGEN test exhibited a sensitivity of 42.11% and a specificity of 100%. The XGEN test was positive in 5 patients with a negative classical slit-skin smear. Furthermore, in our sample, the number of bacilli per reaction detected as positive by the qualitative XGEN kit detected ranged from 3.85 to 21,533.30.
This study demonstrated the ability of both the PoC-ML-FLOW and XGEN tests, along with clinical exams, to diagnose leprosy among HHCs. The use of the XGEN test in the definition of leprosy cases demonstrated a specificity of 100%, with a significant increase in sensitivity when associated with slit-skin smears.
BT - Diagnostic Microbiology and Infectious Disease DO - 10.1016/j.diagmicrobio.2025.116929 IS - 2 N2 -Close household contact with multibacillary leprosy is the primary risk factor for disease transmission. Therefore, early detection of leprosy is crucial for disrupting the transmission chain. The primary objective of this study was to evaluate the diagnostic accuracy of the multiplex XGEN MASTER LEPRAE kit (XGEN) and the point-of-care Bioclin FAST ML FLOW Hanseníase test (PoC-ML-FLOW) among household contacts (HHCs) of leprosy index cases in midwestern Brazil.
We included HHCs of leprosy index cases. After the application of a composite reference standard comprising clinical and laboratory examinations, HHCs were divided into patients with leprosy and controls. The diagnostic accuracy was evaluated using the XGEN and PoC-ML-FLOW.
We included 314 HHCs. Twenty-two HHCs (7%) were diagnosed with leprosy. The PoC-ML-FLOW demonstrated a sensitivity of 45.45% and a specificity of 74.91%. The XGEN test exhibited a sensitivity of 42.11% and a specificity of 100%. The XGEN test was positive in 5 patients with a negative classical slit-skin smear. Furthermore, in our sample, the number of bacilli per reaction detected as positive by the qualitative XGEN kit detected ranged from 3.85 to 21,533.30.
This study demonstrated the ability of both the PoC-ML-FLOW and XGEN tests, along with clinical exams, to diagnose leprosy among HHCs. The use of the XGEN test in the definition of leprosy cases demonstrated a specificity of 100%, with a significant increase in sensitivity when associated with slit-skin smears.
PB - Elsevier BV PY - 2025 EP - 116929 T2 - Diagnostic Microbiology and Infectious Disease TI - Accuracy of the newly manufactured multiplex XGEN MASTER LEPRAE molecular kit and the point-of-care Bioclin FAST ML FLOW test for case definition and early diagnosis of leprosy among household contacts UR - https://www.sciencedirect.com/science/article/pii/S0732889325002524 VL - 113 SN - 0732-8893 ER -