Cajal SP

Date: 
01/03/2014
Investigation Line: 

Abstract

American tegumentary leishmaniasis (ATL) is a group of zoonotic diseases caused by kinetoplastid flagellates of the genus Leishmania. A total of 66 patients diagnosed as positive ATL cases from northwest Argentina were included in this study. Leishmania stocks were isolated in vitro and analyzed over promastigote cultures sown on FTA through nested PCR and sequence of cytochrome b (cyt b). The molecular analysis resulted in the incrimination of L. (Viannia) braziliensis as the predominant species in the studied area, identifying two genotypes of L. (V.) braziliensis, 24 cases of Ab-1 cyt b and 41 cases of Ab-2 cyt b. One L. (V.) guyanensis strain was obtained from a traveler from the Brazilian Amazon. The prevalence of different genotypes was in agreement with previous studies, suggesting the necessity for new systems to study the genetic diversity in more detail. Most of the cases typified in this study were registered in the area of Zenta Valley (Orán, Hipólito Yrigoyen, and Pichanal cities), pointing a link between genotype and geographical origin of the sample. Sex and age distribution of the patients indicate that the transmission was predominantly associated with rural areas or rural activities, although the results might not exclude the possibility of peri-urban transmission. This work represents, so far, the largest isolation and molecular characterization of ATL cases in Argentina.

Date: 
01/09/2003
Investigation Line: 

Abstract

In a study, carried out in 2000, of the clinical and parasitological status of a Wichi Aboriginal community living in the suburbs of Tartagal, northern Salta, Argentina, 154 individuals were screened for parasitic infections. Ninety-five faecal samples were also obtained from the same population. Ninety-three percent of the subjects were positive for 1 or more of the parasites investigated by direct test and 70.5% of them had parasitic superinfection. The most frequent helminths were Strongyloides stercoralis (50.5%) and hookworm (47.4%). We found low reinfection rates and a long reinfection period after treatment and provision of safe water and sanitation. Serum reactivity of these patients was analysed by enzyme-linked immunosorbent assay and indirect immunofluorescent assay and 22.1% of them had anti-Toxocara antibodies, 16.2% were positive for a complex antigen of Leishmania braziliensis, 29.9% were positive for a complex Trypanosoma cruzi antigen, and 17.5% were positive for a specific Trypanosoma cruzi antigen, Ag 163B6/cruzipain.

Date: 
01/01/2003
Investigation Line: 

Abstract

The aims of this study were to characterize human American tegumentary leishmaniasis, which includes cutaneous, mucocutaneous and mucosal leishmaniasis, in Northwest Argentina, to determine the prevalence of double infection with Trypanosoma cruzi and to identify the species of Leishmania in this area. Most of the 330 leishmaniasis patients presented cutaneous ulcers (96.1%), 2.4% mucocutaneous and 1.5% the mucosal form ('espundia'). The aetiological agents, determined by isoenzyme electrophoresis, were identified as Leishmania (Viannia) braziliensis in 16 out of 20 isolates and in the remaining 4 as Leishmania (Leishimania) amazonensis, the first ever-documented in Argentina. Sera analysed by ELISA and IFA using complex antigen from both T. cruzi and L. braziliensis showed a very high percentage of positives (66.3-78.2%). When antigens for specific diagnosis of Chagas' disease were used, 40.9% of the leishmaniasis patients were also found to be infected by T. cruzi. These results indicate that the strong immune response against T. cruzi gave no protection to Leishmania, in spite of the serological cross-reaction between these parasites. In addition, we showed that more than 40% of the patients would be misdiagnosed as chagasic if complex antigens, as epimastigotes or soluble fraction from epimastigotes, were used in IFA or ELISA. This is of paramount importance not only because patients' treatment would be associated to misdiagnosis but the fact that in many countries in Central and South America, a positive test for Chagas' disease means a rejection for those seeking employment.

Date: 
01/01/2000
Investigation Line: 

Abstract

Toxocara canis and Ancylostoma spp. are geohelmints that parasites dogs and can eventually affect humans, mainly children, causing visceral and cutaneous larva migrans respectively, constituting a serious public health problem. This study was carried out in two towns located in the xerophilous forest Chaco salteño where humans live closely with many animals, including dogs. Hematological values and anti-Toxocara canis antibodies, determined by ELISA in serum, were evaluated in 98 children from this area. Thirty-six children presented with eosinophilia of 10% or higher in peripheral blood. Twenty out of 98 (20.4%) children had antibodies against antigen from L2 larvae of Toxocara canis. A high percentage (55.6%) of the children with eosinophilia presented anti-Toxocara canis antibodies. Nine children had multiple serpiginous lesions typical of cutaneous larva migrans. Feces from dogs were collected in the area where children lived, in order to search for parasite contamination. Three different techniques of stool examination were employed and eggs were counted. Out of the 106 feces examined, parasites were found in 82 samples (77.4%). Ancylostoma spp eggs were found in 74 (69.8%) samples and eggs from Toxocara canis were found in 19 (17.2%). The average number of T. canis and Ancylostoma spp eggs/gr of feces, were 200 and 3,871 respectively. Giardia spp (14.5%), Trichuris vulpis (7.6%), Genus Endamoeba (2.8%) and Taenia spp (1.9%) were also identified in the stools. Sanitary control and health education in order to control these parasitoses are emphasized.