American Tegumentary Leishmaniasis and Flow Cytometry: A Review

American Tegumentary Leishmaniasis (ATL) is a parasitic disease caused by protozoans of the genus Leishmania and transmitted by the bite of sandflies. It is considered neglected due to its high incidence and morbidity, mainly in developing countries. The treatment for this disease besides expensive, is toxic and has limitations such as resistance, both from the parasite and the host; and invasiveness, making it not quite acceptable for some patients. There is still no available vaccine for the disease, what makes the correct diagnosis the better alternative to guide the treatment and therefore manage it. The diagnosis of suspected cases has to gather epidemiological, clinical and laboratorial data, since the disease can be misdiagnosed with other dermatological conditions. Immunological methods are commonly used for detecting and monitoring diseases, and the main techniques used in the routine for ATL are the Montenegro Skin Test, Enzyme-linked Immunosorbent Assay, Immunofluorescence Assay and Western Blot. Although these approaches have good sensitivity levels, they lack on specificity and have some limitations like crossed-reactions with other diseases caused by trypanosomatid parasites. One different serological approach, which is becoming an alternative method for the diagnosis of this disease, is Flow Cytometry; it has shown balanced levels of specificity and sensitivity and also a better accuracy when compared to other methods used in routine. Therefore, this article shows the recent advances on the diagnosis of ATL by flow cytometry and by using the findings on the literature, aims to guide researchers on what should be the focus to have a better diagnostic method for this disease.