Puzzling paracoccidioidomycosis: Factors associated with the severity of Paracoccidioides lutzii infections

•Paracoccidioidomycosis (PCM) is a neglected tropical disease mainly seen in South America.•Paracoccidioides brasiliensis and Paracoccidioides lutzii are the causes of paracoccidioidomycosis.•In Brazil, paracoccidioidomycosis accounts for 50% of deaths due to systemic mycoses.•A high neutrophil to lymphocyte ratio is indicative of severe paracoccidioidomycosis.•Testing for the neutrophil to lymphocyte ratio is an easy and low-cost diagnostic tool. Historically, the Brazilian Central-West region has had high numbers of paracoccidioidomycosis (PCM) cases caused by the dimorphic fungus Paracoccidioides lutzii. This epidemiological, observational, analytical, cross-sectional study was performed to investigate the clinical and laboratory data of 44 PCM patients with a culture-proven P. lutzii infection. All patients were referred to the Systemic Mycosis Center, Júlio Muller University Hospital, Cuiabá, Brazil, during January 2017 to March 2020. The neutrophil to lymphocyte ratio (NLR) was calculated and dichotomized by its median value to include in the identification of factors associated with severity. At admission, 13 (31.7%) patients showed the disseminated multifocal chronic form of PCM and 16 (36.4%) patients met the clinical severity criteria. Treatment prescribed on admission did not follow the recommendations of the Brazilian Guideline for the Clinical Management of Paracoccidioidomycosis in 26% of the severe PCM cases (prevalence ratio 0.26, 95% confidence interval 0.14–0.49; P < 0.0001). Patients with severe PCM had a higher NLR that was greater than the median (≥4.11). The NLR biomarker complements the criteria for PCM severity. Applying the low-cost NLR test can greatly increase the diagnostic sensitivity when screening patients for PCM and contribute to better control of the disease, management of complications, and therapeutic strategies.