Hookworm-related
cutaneous larva migrans (Hr-CLM) is caused by animal hookworm larvae migrating in the human epidermis where they elicit an inflammatory response. This study describes the immunological profile in Hr-CLM patients. In 77 Hr-CLM patients from Manaus, Brazil, peripheral eosinophils were counted, and serum concentrations of total
immunoglobulin E (
IgE) and selected
cytokines were determined by ELISA before and
after treatment with
ivermectin. Controls included patients' household members (endemic controls), non-endemic Brazilian and Japanese individuals. Eosinophil counts and total
IgE in Hr-CLM patients were higher than in controls and correlated with disease severity. Concentrations of
interleukin (IL)-4,
IL-5,
IL-6, and
IL-10 were higher in Hr-CLM patients than in endemic controls (p < 0.001) while no differences were detected for
interferon (IFN)-γ,
tumor necrosis factor (TNF)-α, IL-1β,
IL-2, or
transforming growth factor (TGF)-β. Following
ivermectin treatment, numbers of eosinophils and concentrations of
IL-4,
IL-5, and
IL-10 decreased whereas
IgE, IFN-γ, and TGF-β concentrations increased. The IL-5/IFN-γ ratio declined from 5.9 (interquartile range [IQR] 0.8-31.6) before to 0.1 (IQR 0.05-0.2; p = 0.001)
after treatment. Thus, although an impact of other
infections on the immune parameters determined cannot be excluded, Hr-CLM in endemic areas is associated with
eosinophilia and elevated
cytokine levels, particularly of
IL-5 and
IL-10, which decrease following
ivermectin treatment.