Leishmania Antibody (IgG) - Detection of Leishmania IgG provides strong support for the diagnosis of visceral leishmaniasis. Some (but not all) patients with cutaneous leishmaniasis also have detectable serum levels of Leishmania IgG. Sera from patients with Trypanosoma cruzi infection (Chagas disease) show significant cross-reactivity in the Leishmania IgG assay. This assay is intended to aid in the diagnosis of visceral leishmaniasis. Its use in diagnosing cutaneous leishmaniasis is limited, since a detectable antibody response is often absent in this form of the disease. Sera from patients with Chagas disease (Trypanosoma cruzi infection) may be positive in this assay; thus, results should be used in conjunction with other clinical findings when considering a diagnosis of leishmaniasis.