Laboratory confirmation of tegumentary leishmaniasis cases in the southern Brazilian Amazon, 2007-2022: Temporal trends, spatial patterns and associated factors.

Laboratory confirmation of tegumentary leishmaniasis (TL) has been prioritized by the Pan American Health Organization (PAHO) in the Americas, given the potential toxicity of antileishmanial treatments and broad differential diagnoses. This population-based study analyzed temporal trends, spatial patterns, and determinants of laboratory confirmation of TL cases reported between 2007 and 2022 in Mato Grosso-a highly endemic state in the southern Brazilian Amazon. Temporal trends in the percentage of laboratory-confirmed cases were assessed for the state and its five mesoregions using joinpoint regression. Spatial clustering at the municipal level was evaluated using Moran's I statistics. Contextual- and individual-level determinants were investigated through multilevel logistic regression modelling with municipalities as random effects. Among 36,696 reported TL cases, 88.1 % were laboratory-confirmed. Although annual confirmation rates frequently exceeded the PAHO target (≥80 %), a significant declining trend was observed for the state and most mesoregions. High-High clusters of laboratory confirmation were concentrated in high-endemic areas, whereas a Low-Low cluster comprised lower-endemic municipalities. Higher TL incidence rates were the only contextual-level variable associated with higher odds of laboratory-based diagnosis. At the individual level, White/Asian individuals, cases not reported in primary healthcare facilities, and cutaneous cases showed higher odds of laboratory confirmation, whereas notification in a municipality other than the place of residence was associated with lower odds. Despite overall high laboratory confirmation rates, decreasing trends, spatial heterogeneity, and lower participation of the primary healthcare suggest important diagnostic gaps, highlighting the need to strengthen laboratory capacity and coverage, particularly in lower-incidence areas, to sustain PAHO targets.