Epidemiological studies have been conducted to better understand the dynamics of American Cutaneous Leishmaniasis (ACL) in the Amazon region where distinct species of Leishmania circulate. In endemic areas, the optimal diagnosis must be made in the earlier clinical presentation to avoid the complications of chronic disease. The scarcity of financial support, laboratory infrastructure and trained persons are the major obstacles in this reality. This paper describes the result of performing different diagnostic methods for ACL in Amazonas State between the years 2010 and 2011. The tests used were the intradermal skin test (Montenegro's skin test), ELISA (Enzyme-Linked Immunosorbent Assay), direct examination, culture isolation and identification of Leishmania species. A total of 38 suspected human cases of ACL were diagnosed by different methods, of which 71.0% (n = 27) were positive by direct examination, 75.6% (n = 28) had positivity in the culture isolates and, of these, 54.0% (n = 19) had infection with Leishmania (Viannia) guyanensis. The positivity of the intradermal skin test with the leishmanin solution was observed in 77.0% of cases analyzed and the serology with detection of IgG and IgM showed the presence of antibodies in 100% of exams realized results, showing variation in the titles of antibodies. The success of Leishmaniasis treatment depends on an effective and early diagnosis. Parasitological diagnosis is highly specific, but sensitivity is subject to variation because the tissue distribution of parasites generally is not homogeneous and depends on the specie of parasite. Moreover, parasitological tests require invasive procedures and depend on restrictive conditions for the collection of biological sample, which limit their use in large-scale for epidemiological studies. ELISA has been the most widely used serological method for the diagnosis of Visceral Leishmaniasis (VL) as it is easy to perform and has a low cost. However, flaws in specificity are observed in the diagnosis of cutaneous leishmaniasis. Actually the diagnosis needs to be done as an associated methods depending on the question to be solved.

The authors discuss in this paper the role of inflammatory, anti-inflammatory, and regulatory cytokines in patients infected with different species of Leishmania in Amazonas State, Brazil. A comparative analysis was made of serum concentrations of these cytokines in the peripheral blood of 33 patients infected with cutaneous leishmaniasis. The isolates were identified as Leishmania guyanensis, L. naiffi, and L. amazonensis. Most (64%) of the patients were male ranging in age from 18 to 58 years. Protein expression profiles of IL-2, IL-4, IL-6, IL-10, IFN-γ, TNF-α, and IL-17 cytokines were shown to vary significantly between infected and noninfected (control group) individuals and according to the Leishmania species. Infection caused by L. guyanensis accounted for 73% of the cases and patients with this parasite also showed higher concentrations of IL-2, IFN-γ, IL-4, and IL-17 when compared to infection by L. amazonensis. Patients with infection caused by L. naiffi showed higher concentration of the cytokines analyzed when compared to uninfected patients; however, there was no statistically significant difference with the other species analyzed.

Foram analisados os aspectos clínicos e epidemiológicos de 90 pacientes com leishmaniose tegumentar americana (LTA) no município de Rio Preto da Eva, estado do Amazonas, Brasil, entre os anos de 2005 e 2012. Todos os pacientes apresentavam lesões cutâneas cujas cepas isoladas foram caracterizadas por eletroforese de isoenzimas e identificadas como Leishmania (Viannia) guyanensis (n=80), Leishmania (V.) naiffi (n=3) e Leishmania (Leishmania) amazonensis (n=7). A maior parte dos pacientes era do sexo masculino (70%) e a faixa etária com maior número de casos foi de 11 a 20 anos (31,7%). Em relação à ocupação, a maioria era constituída por agricultores ou caseiros (37,7%). Um percentual de 95% dos casos de LTA era proveniente de focos endêmicos de zonas rurais. O Assentamento Iporá, localizado no km 127 da AM 010, apresentou o maior número de casos (33,3%). Concluímos que a LTA é uma parasitose endêmica de importância no município de Rio Preto da Eva, ocorre principalmente ao longo da rodovia AM 010 e, nos pacientes analisados, a aquisição da infecção ocorreu, majoritariamente, por meio de contato com o ciclo silvestre de transmissão, ressaltando-se, porém, a possibilidade de transmissão da doença no intra e peridomicílio.