02987nas a2200301   4500000000100000008004100001260004400042653002900086653001200115653002000127653002500147100001600172700001300188700001800201700001600219700001600235700001500251700001700266700001700283700001400300700001600314700001600330700001700346700002200363245008600385520218900471022002502660       2025                            d  bSpringer Science and Business Media LLC10aFast ML Flow Hanseníase10aLeprosy10aTest Evaluation10aPublic Health Brazil1 aSaavedra DP1 aNobre ML1 aGuimarães RA1 aFogaça MBT1 aGoulart IMB1 aBarreto JA1 ade Souza VNB1 aJeronimo SMB1 aAmorim FM1 ada Silva TP1 aPinheiro RO1 aStefani MMDA1 aBührer-Sékula S00aA Multicenter evaluation of leprosy rapid test Fast ML Flow Hanseníase in Brazil3 a<p><strong>Purpose:&nbsp;</strong>Leprosy represents a public health concern; its diagnosis remains clinical. Recently, the Brazilian public health system/SUS incorporated the leprosy-specific IgM anti-PGL-I rapid test Fast ML Flow Hanseníase (MLFH/Bioclin, Brazil; originally ML Flow) to aid leprosy contacts surveillance and diagnosis. Anti-PGL-I antibody levels correlate with bacterial load. This multicenter study evaluated MLFH performance in confirmed leprosy cases from four Brazilian reference centers.</p>

<p><strong>Methods:&nbsp;</strong>MLFH results were compared to anti-PGL-I ELISA, bacilloscopy/BI and analyzed in indeterminate/I, pure neuritic/PN and in Ridley Jopling/RJ categories (tuberculoid/TT, borderline-tuberculoid/BT, borderline/BB, borderline-lepromatous/BL, lepromatous/LL). Leprosy patients’ serum samples (N = 158; 95 multibacillary/MB, 63 paucibacillary/PB) were evaluated. Additionally, 20 previously tested leprosy samples were distributed to each center to assess MLFH repeatability, inter-center and inter-operator reproducibility.</p>

<p><strong>Results:&nbsp;</strong>Higher MLFH seropositivity (84.8%) compared to ELISA (60.8%;&nbsp;<em>p</em> &lt; 0.001) and bacilloscopy (50.6%;&nbsp;<em>p</em> &lt; 0.001), indicated moderate and fair agreement, respectively. Visual intensity readings (0 to 4 + range) from 20 samples showed excellent agreement (ICC: 0.954); test repeatability was 95.57%. Compared to ELISA and bacilloscopy, positivity difference was statistically significant (<em>p</em> &lt; 0.05) in TT, BT, and I forms. Lower MLFH positivity was observed in indeterminate, BT and PN forms.</p>

<p><strong>Conclusion:&nbsp;</strong>The change in MLFH result criteria adopted by Bioclin/SUS considering faint test line (0.5) as positive (originally negative in ML Flow), increased MLFH sensitivity leading to higher seropositivity in MB and especially in PB, known as weak antibody producers. However, when screening asymptomatic leprosy contacts, this modified criterion may lead to reduced specificity since in endemic areas, anti-PGL-I positivity alone does not necessarily indicate active disease.</p>
  a0934-9723, 1435-4373