Human Lobomycosis Caused by Paracoccidioides (Lacazia) loboi, Panama, 2022

Abstract

We report a patient from Panama who had lobomycosis caused by Paracoccidioides (Lacazia) loboi. We used combined clinical-epidemiologic and phylogenetic data, including a new gene sequence dataset on this fungus in Panama, for analysis. Findings contribute useful insights to limited knowledge of this fungal infection in the Mesoamerican Biologic Corridor.

Keywords: Panama; Paracoccidioides (Lacazia) loboi; fungal infections; fungi; human lobomycosis; lacaziosis.

Figure 1

Lesions from an 87-year-old woman from Capira in western Panama, determined to be lobomycosis caused by infection with the fungus Paracoccidioides (Lacazia) loboi. A, B) Multiple keloid-like nodules on the left leg extending through the mid-distal third of the posterior aspect of the left thigh of the patient who had lobomycosis. Shown are the classic confluent arrangement and hyperpigmented aspect of lesions. C) Tissue stain showing classic oval-to-round-shaped cells with connecting tubular projections arranging in a string-of-pearls pattern, both in pairs and individually. Gömöri methenamine silver stain; original magnification ×100.

Figure 2

Phylogenetic relationship of ADP-rf, Gp43, and internal transcribed spacer (ITS) 1 and 2 genes from patient in Panama who had lobomycosis with other Paracoccidioides species. Trees indicate phylogenetic analysis inferred by maximum-likelihood method of the ADP-rf (A), Gp43 (B), and ITS1–ITS2 (C) genes. Analyses included sequences obtained from research conducted by Vilela et al. (7) and the Panama case analyzed in this study (red). Each color in the trees represent different clusters identified: yellow, Paracoccidioides cetti; white, P. restrepiensis/venezuelensis; gray, P. brasiliensis; green, P. americana; light blue, P. lutzii; and light purple, P. loboi. Gray triangles indicate genomes of the same clade belonging to P. restrepiensis, P. venezuelensis, or P. brasiliensis (to the ADP-rf gene, 49 genomes; to the Gp43 gene, 32 genomes; and to ITS1-ITS2 gene, 52 genomes). Histoplasma capsulatum and Ajellomyces capsulatus DNA sequences were used as outgroups for ADP-rf and ITS genes, respectively. Scale bars indicate nucleotide substitutions per site.