Leishmaniose cutânea americana no Pontal do Paranapanema - SP: avaliação clínica, histopatológica e uso da reação em cadeia da polimerase (PCR) para identificação e caracterização das espécies de Leishmania / American cutaneous leishmaniasis in the Pontal do Paranapanema SP: clinical, histopathological evaluation and use of Polymerase Chain Reaction (PCR) for identification and characterization of the Leishmania species

AUTOR(ES)
DATA DE PUBLICAÇÃO

2007

RESUMO

Leishmaniasis are parasitic diseases caused by protozoans of the Leishmania genus and are important public health problems. American cutaneous leishmaniasis (ACL) is considered an autochthonous disease of the American continent and presents several clinical forms which depend on the causative species of the infection and other factors such as virulence and ability to evade the immune system. Six Leishmania species are recognized to cause human ACL cases in Brazil of which five belong to the Viannia and one to the Leishmania subspecies. They are: Leishmania (Viannia) braziliensis, Leishmania (Viannia) guyanensis, Leishmania (Viannia) lainsoni, Leishmania (Viannia) shawi, Leishmania (Viannia) naiffi and Leishmania (Leishmania) amazonensis. Cutaneous leishmaniasis transmission is maintained in the Pontal do Paranapanema region, with 20 notified cases in 2006. Leishmania (V.) braziliensis is the only species considered to be the disease agent in the region with identification of the involved vectors and possible wild reservoirs. The aim of this research is the studies of the epidemiological, clinical and histopathological aspects of cutaneous leishmaniasis in the Pontal do Paranapanema and the identification by molecular methods, PCR, of the etiologic agent and characterization of the Leishmania genus, subgenus and species present in the region. The disease was found in both genders, with predominance of males (67.9%), in all age ranges, but 70.5% were in the range of 20 to 49 years. The cutaneous was the mostly found clinical form with 92.3% of the cases. Search for the parasite in the lesion of 78 patients who underwent biopsies was positive in 40 samples (51.5%), in HE stained slides; when IH was used, 66.7% were positive. Agreement index between the HE and IH techniques were 58.97%. However, 10 negative cases using IH were positive with HE, and of 38 HE negative cases 22 were positive using IH. This shows that association of the two methods is needed. Using PCR, there was a positivity of 53.8%. Evaluating the results obtained in this study, we may observe that of the 40 HE positive cases 24 were also positive on PCR; but 16 of these were PCR negative. Contrariwise, of the 38 HE negative samples 18 were positive PCR. Using immunohistochemistry, of the total of 38 HE negative samples, 18 were positive with PCR; while of the 52 IH positive samples, 28 were positive and 24 negative on PCR. Agreement levels of PCR with HE were 56.41%, and of PCR with IH 51.28%. These results reinforce the idea of the need for association of the three methods for CL diagnosis. Histopathological lesion characteristics were: granulomatous reaction (GR) found in 71.85%, granulomatous reaction with giant cells (GRGC) in 12.8T, granulomatous reaction with necrosis (GRN) in 10.3% and granuloma with necrosis and giant cells (GRNGC) in 5.1% of the cases. Using SSU rDNAS 17/S18 primers it was possible to characterize through sequencing 27 (34.6%) samples as being of the Viannia subgenus and 06 samples of the L. (L.).amazonensis This study identified the first L. (L.) amazonensis case in the region

ASSUNTO(S)

leishmania doenças parasitárias leishmania leishmania braziliensis parasite disease leishmania braziliensis leishmaniose cutânea polymerase chain reaction cutaneous leishmaniasis reação em cadeia da polymerase

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