Lobomycosis is a disease that is endemic to the Amazon rainforest and is caused by the still uncultured fungus Lacazia loboi. This disease occurs in loggers, farmers, miners, fishermen, and persons living near coastal rivers of this region. We report 6 soldiers in Colombia in whom lobomycosis developed after military service in the Amazon area. The patients had nodular and keloid-like lesions on the face, neck, trunk, and limbs. The duration of illness ranged from 2 years to 15 years. The initial diagnosis was leishmaniasis on the basis of clinical manifestations and direct smear results, but biopsies confirmed the final diagnosis of lobomycosis. Treatment with surgical excision, itraconazole and clofazimine was satisfactory. However, the follow-up time was short. Healthcare professionals responsible for the diagnosis and treatment of skin diseases need to be able to recognize the clinical signs of lobomycosis and differentiate them from those of cutaneous leishmaniasis.

The pathogenesis of lacaziosis continues to be obscure, and works have investigated the blood systemic immune response or the dermal immune response in restricted lesions in different body regions. Some authors describe that the inflammatory infiltrate in lacaziosis lesions showed a predominance of macrophages followed by CD45RO(+), CD4(+), and CD8(+) T cells; CD57(+) natural killer cells; S-100(+) cells; and CD20(+) B lymphocytes. A 54-year-old man and living in the State of Para, Amazon region, Brazil, was seen with a lesion on the left lower limb, which had started as a small nodular area 18 years ago. The lesion showed progressive growth and disseminated to other parts of the body. Our findings showed that dermal immune response differs depending on the type of lesions and clinical presentation, with presence of CD1a(+), FXIIIa(+), CD45(+), CD4(+), CD8(+), and S-100(+) cells and cytokine profile with expression of interleukin 1 β, tumor necrosis factor α, transforming growth factor β, IL-10, and interferon γ.