RESUMO
Leishmaniases are vector-borne diseases that in the Americas are distributed from southern United States to northern Argentina. The vectors for this disease are small dipterans known as sand flies that are usually identified morphologically by observing structures with taxonomic value; but it is time-consuming, laborious, and requires entomological expertise. Then, this work was aimed at identifying sand flies with molecular techniques, using the morphological identification as a reference technique, in an endemic area of American Tegumentary Leishmaniasis (ATL) located in northern Argentina. For this, sand flies were caught at two patches of vegetation adjacent to rural areas in Orán department, Salta Province. Females were dissected with sterile needles; the head and last abdominal segments were analyzed for morphological identification. The remaining thorax and abdominal segments were used to extract DNA, which was amplified by PCR of the small subunit (SSU), 18S rRNA gene. PCR products were digested with CviQI and DdeI enzymes to identify sand fly species by Restriction Fragment Length Polymorphism (RFLP) analysis. Thus, the restriction pattern of each caught species was defined according to morphological identification. A total of 1501 females, belonging to four sand fly species, were captured. Nyssomyia neivai (1347/1501) was the most abundant species, followed by Migonemyia migonei (90/1501). From the total, 801 females were morphologically and molecularly identified, while 700 females were characterized only molecularly. For those females analyzed by both methods, there was total coincidence in the achieved result. Besides, the 5% (38/801) of females that could not be determined morphologically due to inadequate mounting were molecularly identified. All the females characterized just by PCR-RFLP, were successfully identified. Our results indicate that the explored method is capable of identifying the sand fly species that circulate in an ATL endemic area. Since this method is based on the analysis of markedly different patterns, the identification process might be more easily reproduced, as the bias introduced by the technician's lack of experience is removed.
Assuntos
Insetos Vetores/classificação , Insetos Vetores/genética , Polimorfismo de Fragmento de Restrição , Psychodidae/classificação , Psychodidae/genética , RNA Ribossômico 18S/genética , Animais , Argentina/epidemiologia , Feminino , Leishmaniose Cutânea/epidemiologiaRESUMO
The diagnosis of American tegumentary leishmaniasis (ATL) still requires the design of more effective tools. Leishmania (Viannia) braziliensis is the causal agent of the 90% of Argentinean ATL cases. Considering the current knowledge, an ELISA based crude antigen (CA) for the diagnosis was designed. Ninety-nine subjects diagnosed as ATL, 27 as no-ATL, and 84 donors from non-ATL-endemic areas were included in this study. The current ATL diagnosis was based four techniques, dermal smear microscopic examination (parasitological test), PCR, Leishmanin skin test, and clinical records. We obtained CA extracts from promastigotes and amastigotes from macrophage cultures of different zymodemes of endemic Leishmania species circulating in the study area. Crude antigens from the 'local' main zymodeme of L. (V.) braziliensis showed the highest reactivity against anti-Leishmania antibodies compared to the other included species. The CA of amastigotes of this zymodeme was 3.4 fold more reactive than promastigotes one. Moreover, amastigote-membrane CA (MCA) were 3.6 fold more reactive than the soluble antigens. The MCA-ELISA reached a sensitivity and specificity of 98% (CI = 94.7%-100%) and 63.6% (53.9-73.1), respectively. When anti-Trypanosoma cruzi reactive sera were excluded, the specificity reached 98.4% (94.4-100), while the sensitivity was similar, with a positive predictive value (PV) of 98.6% (94.6-100) and negative PV of 96.3% (91.6-100). The performance of the MCA-ELISA results strongly contribute to the final diagnostic decision, since a non-reactive serological result almost discards the suspected ATL, because of its high negative PV. The developed MCA-ELISA showed a high diagnostic performance, which makes it a good candidate for ATL diagnosis, for seroprevalence studies, or for monitoring treatments efficacy.
Assuntos
Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Membrana Celular/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Leishmania braziliensis/imunologia , Leishmaniose Cutânea/diagnóstico , Afinidade de Anticorpos , Especificidade de Anticorpos , Argentina/epidemiologia , Doadores de Sangue , Doenças Endêmicas , Humanos , Leishmania braziliensis/crescimento & desenvolvimento , Leishmaniose Cutânea/sangue , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Leishmaniose Mucocutânea/sangue , Leishmaniose Mucocutânea/diagnóstico , Leishmaniose Mucocutânea/parasitologia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Trypanosoma cruzi/imunologiaRESUMO
The treatment of leishmaniasis includes pentavalent antimony drugs but, because of the side effects, toxicity and cases of treatment failure or resistance, the search of new antileishmanial compounds are necessary. The aims of this study were to evaluate and compare the in vitro antileishmanial activity of four green tea catechins, and to assess the efficacy of topical (-)-epigallocatechin gallate in a cutaneous leishmaniasis model. The antileishmanial activity of green tea catechins was evaluated against intracellular amastigotes, and cytotoxicity was performed with human monocytic cell line. BALB/c mice were infected in the ear dermis with Leishmania (Leishmania) amazonensis and treated with topical 15% (-)-epigallocatechin gallate, intraperitoneal Glucantime, and control group. The efficacy of treatments was evaluated by quantifying the parasite burden and by measuring the lesions size. (-)-Epigallocatechin gallate and (-)-epigallocatechin were the most active compounds with IC50 values <59.6 µg/mL and with a selectivity index >1. Topical treatment with (-)-epigallocatechin gallate decreased significantly both lesion size and parasite burden (80.4% inhibition) compared to control group (p < 0.05), and moreover (-)-epigallocatechin gallate showed a similar efficacy to Glucantime (85.1% inhibition), the reference drug for leishmaniasis treatment.
Assuntos
Antiprotozoários/administração & dosagem , Catequina/análogos & derivados , Catequina/administração & dosagem , Leishmaniose Cutânea/parasitologia , Chá/química , Animais , Antiprotozoários/química , Catequina/química , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Leishmania mexicana/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Camundongos , Testes de Sensibilidade ParasitáriaAssuntos
Antiprotozoários/uso terapêutico , Leishmania braziliensis/genética , Leishmaniose Cutânea/diagnóstico , Leishmaniose Mucocutânea/diagnóstico , Antimoniato de Meglumina/uso terapêutico , Adulto , Argentina , Genótipo , Técnicas de Genotipagem , Humanos , Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Leishmaniose Mucocutânea/tratamento farmacológico , Leishmaniose Mucocutânea/parasitologia , MasculinoRESUMO
Background: Some sand flies are of medical importance because they are vectors of Leishmania parasites that are responsible for leishmaniasis. The aim of this study was to make a retrospective epidemiological analysis of tegumentary leishmaniasis (TL), to identify Leishmania spp. from patient isolates and to describe the diversity of sand flies from a border area between Bolivia and Argentina. Methods: TL cases included in the study were diagnosed in an endemic area of the north of Argentina from 1985 to 2017. The parasites isolated were characterized by the cytochrome B method. Sand flies were captured with Centers for Disease Control traps in Aguas Blancas and Media Luna-Algarrobito localities. Results: A total of 118 cases of TL were analysed. Eight isolates were characterized as Leishmania (Viannia) braziliensis. A total of 1291 sand flies were captured, including Nyssomyia neivai, Cortelezzii complex, Evandromyia sallesi, Migonemyia migonei and Micropygomyia quinquefer. Within the area, sand flies were found in the backyards of houses. Conclusions: In this region there exists the possibility of peridomestic transmission of TL in the neighbourhoods peripheral to the urban area and in rural environments as well as the risk of transmission to travellers that pass through the customs offices.
Assuntos
Insetos Vetores/parasitologia , Leishmaniose/epidemiologia , Leishmaniose/transmissão , Psychodidae/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Argentina/epidemiologia , Bolívia/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
Pulmonary metastrongylosis, a zoonotic disease found primarily in pigs, is caused by eight different species of the cosmopolitan nematode Metastrongylus genus. To date, only four human cases have been reported, all from Europe. Herein, a severe case of pulmonary infection caused by Metastrongylus salmi in an Ecuadorian man, with successful treatment with ivermectin, is described.
Assuntos
Pneumonia/diagnóstico , Infecções por Strongylida/diagnóstico , Animais , Antiparasitários/uso terapêutico , Equador , Humanos , Ivermectina/uso terapêutico , Masculino , Metastrongyloidea/isolamento & purificação , Metastrongyloidea/ultraestrutura , Pessoa de Meia-Idade , Pneumonia/tratamento farmacológico , Escarro/parasitologia , Infecções por Strongylida/tratamento farmacológicoRESUMO
Leishmaniases comprise zoonotic diseases caused by protozoan flagellates of the Leishmania genus. They are endemic to South America, and the visceral form has been recently reported in Argentina. Dogs can play different roles in the Leishmania transmission cycles, depending mainly on the species of parasite involved. Here we focused on the clinical characterization of canine leishmaniasis (CanL) in Northeast Argentina and on the molecular typing of its etiological agent. The nested polymerase chain reaction and sequence analysis of the Leishmania cytochrome b (cyt b) gene was performed on DNA templates purified from lymph nodes, bone marrow or spleen aspirates obtained from 48 dogs previously diagnosed by the observation of Leishmania amastigotes on smears from these aspirates. Their clinical and epidemiological data were also recorded. Systemic abnormalities were observed in 46 subjects (95.8%), most frequently lymphadenopathy, and emaciation (89.6 and 75%). Furthermore, 87% also presented tegumentary abnormalities, such as alopecia (54.2%) or secondary skin lesions (47.9%), among others. Twenty three dogs were positive for cyt b amplification. The sequence analysis showed the presence of two genotypes, LiA1 and LiA2, assigned to Leishmania (Leishmania) infantum, with 99.9 and 100% homology with the reference strain MHOM/TN/80/IPT1 respectively. LiA1 was identified in 18 cases (78.3%) and LiA2 in five (21.7%). Two cyt b variants of L. (L.) infantum were incriminated as the causative agents of CanL cases from three cities: Posadas, Garupá, and Ituzaingó. All three cities are located in the northeastern area of the country, where these parasites seem to be spreading in urban areas.
Assuntos
Doenças do Cão/epidemiologia , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/veterinária , Animais , Argentina/epidemiologia , Reservatórios de Doenças , Cães , Feminino , Leishmania infantum/genética , Leishmaniose Visceral/epidemiologia , Masculino , Reação em Cadeia da Polimerase , ZoonosesRESUMO
Cases of human visceral leishmaniasis (HVL) were not recorded until recently in the Chaco region of northwestern Argentina. Dogs were surveyed at the sites of infection of two HVL index cases in the Chaco region of Salta province. Canine cases (CanL) were diagnosed by two parasitological methods, two molecular methods targeting mini- and maxicircle DNA, and immunochromatographic dipstick. Among 77 dogs studied, 10 (13%) were found infected with Leishmania spp. In seven dogs and two humans, the infecting species was typed as Leishmania (Leishmania) infantum. The same genotype was detected in the human and two of the CanL. Although several diagnostic methods displayed weak or moderate agreement, the concordance values for serology versus maxicircle PCR were very good (Kappa index = 0.84). Sandflies captured in the area were identified as Lutzomyia migonei and Lu. cortelezzii/Lu. sallesi (cortelezzii complex). The focal appearance of leishmaniasis in dogs and humans in a sylvatic region and its relatively low prevalence of infection suggests that L. (L.) infantum transmission to dogs and humans may, in this region, stem from sylvatic reservoirs.
Assuntos
Doenças do Cão/epidemiologia , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Adulto , Animais , Argentina/epidemiologia , Citocromos b/genética , DNA de Protozoário/isolamento & purificação , Doenças do Cão/parasitologia , Cães , Feminino , Genótipo , Humanos , Lactente , Insetos Vetores/parasitologia , Leishmania infantum/genética , Masculino , Reação em Cadeia da Polimerase/veterinária , Prevalência , Psychodidae/parasitologiaRESUMO
Leishmaniasis is a vector-borne protozoan infection affecting over 350 million people around the world. In Argentina cutaneous leishmaniasis is endemic in nine provinces and visceral leishmaniasis is spreading from autochthonous transmission foci in seven provinces. However, there is limited information about the diversity of the parasite in this country. Implementation of molecular strategies for parasite typing, particularly multilocus sequence typing (MLST), represents an improved approach for genetic variability and population dynamics analyses. We selected six loci as candidates implemented in reference strains and Argentinean isolates. Phylogenetic analysis showed high correlation with taxonomic classification of the parasite. Autochthonous Leishmania (Viannia) braziliensis showed higher genetic diversity than L. (Leishmania) infantum but low support was obtained for intra-L. braziliensis complex variants suggesting the need of new loci that contribute to phylogenetic resolution for an improved MLST or nested-MLST scheme. This study represents the first characterization of genetic variability of Leishmania spp. in Argentina.
Assuntos
Leishmania/classificação , Leishmania/genética , Leishmaniose/epidemiologia , Leishmaniose/parasitologia , Tipagem de Sequências Multilocus/métodos , Animais , Argentina/epidemiologia , DNA de Protozoário/análise , DNA de Protozoário/genética , Cães , Haplótipos , Humanos , Leishmaniose/veterinária , FilogeniaRESUMO
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.
Assuntos
Citocromos b/classificação , Leishmania braziliensis/isolamento & purificação , Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Filogenia , Proteínas de Protozoários/classificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Argentina/epidemiologia , Criança , Pré-Escolar , Citocromos b/genética , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Leishmania/classificação , Leishmania/genética , Leishmania braziliensis/classificação , Leishmania braziliensis/genética , Leishmaniose Cutânea/parasitologia , Masculino , Pessoa de Meia-Idade , Prevalência , Proteínas de Protozoários/genéticaRESUMO
The genetic divergence caused by genetic drift and/or selection is suggested to affect the vectorial capacity and insecticide susceptibility of sand flies, as well as other arthropods. In the present study, cytochrome b (cyt b) gene sequences were determined in 13 species circulating in Peru to establish a basis for analysis of the genetic structure, and the intraspecific genetic diversity was assessed in the Lutzomyia (Lu.) peruensis, a main vector species of Leishmania (Viannia) peruviana in Peruvian Andes. Analysis of intraspecific genetic diversity in the cyt b gene sequences from 36 Lu. peruensis identified 3 highly polymorphic sites in the middle region of the gene. Haplotype and gene network analyses were performed on the cyt b gene sequences of 130 Lu. peruensis in 9 Andean areas from 3 Departments (Ancash, Lima and La Libertad). The results showed that the populations of La Libertad were highly polymorphic and that their haplotypes were distinct from those of Ancash and Lima, where dominant haplotypes were observed, suggesting that a population bottleneck may have occurred in Ancash and Lima, but not in La Libertad. The present study indicated that the middle region of the cyt b gene is useful for the analysis of genetic structure in sand fly populations.
Assuntos
Citocromos b/genética , Variação Genética , Insetos Vetores/genética , Leishmania/fisiologia , Leishmaniose/transmissão , Psychodidae/genética , Animais , Sequência de Bases , Genética Populacional , Genótipo , Geografia , Haplótipos , Insetos Vetores/enzimologia , Insetos Vetores/parasitologia , Leishmaniose/epidemiologia , Proteínas Mitocondriais/genética , Dados de Sequência Molecular , Peru/epidemiologia , Filogenia , Psychodidae/enzimologia , Psychodidae/parasitologia , Análise de Sequência de DNARESUMO
BACKGROUND: The diagnosis of the leishmaniases poses enormous challenges in Argentina. The Polymorphism-Specific PCR (PS-PCR) designed and validated in our laboratories has been proven effective for typifying the Leishmania genus from cultured material. Here we evaluated the performance of this method in the diagnosis of American tegumentary leishmaniasis (ATL) and the rapid identification of Leishmania spp. directly from clinical specimens. METHODS: A total of 63 patients from northwestern Argentina, with cutaneous or mucocutaneous lesions, underwent an ATL diagnosis protocol which included clinical examination, Leishmanin skin test, and microscopic examination of dermal smears. In addition, we performed PS-PCR on DNA directly extracted from the specimens scraped from the lesions. RESULTS: Out of the 63 patients, 44 were classified as ATL cases and 19 as non-ATL cases. The diagnostic sensitivity of the microscopic analysis of dermal smears and PS-PCR individually were 70.5% and 81%, respectively. When performing both tests in parallel, this parameter increased significantly to 97.6% (p = 0.0018). The specificities, on the other hand, were 100%, 84.2%, and 83.3% for the combination, respectively (p > 0.05). Using the PS-PCR analysis we successfully identified the Leishmania spp. in 31 out of the 44 ATL cases. Twenty-eight (90.3%) cases were caused by L. (V.) braziliensis, two (6.5%) by L. (V.) guyanensis, and one (3.2%) by L. (V.) panamensis. CONCLUSIONS: The efficacy of the ATL diagnosis was significantly improved by combining the dermal smear examination with a PS-PCR analysis. Our strategy allowed us to reach the diagnosis of ATL with high accuracy regarding the species of the etiological agent in 70.5% of the cases. Moreover, we diagnosed two cases of the disseminated cutaneous form caused by L. (V.) braziliensis and a cutaneous case due to L. (V.) panamensis infection, both findings reported for the first time in Argentina.
Assuntos
Leishmania/classificação , Leishmania/isolamento & purificação , Leishmaniose Cutânea/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Parasitologia/métodos , Reação em Cadeia da Polimerase/métodos , Adulto , Argentina , Feminino , Humanos , Leishmania/genética , Masculino , Pessoa de Meia-Idade , Sensibilidade e EspecificidadeAssuntos
Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/diagnóstico , Adulto , Argentina , Medula Óssea/parasitologia , Citocromos b/genética , Humanos , Leishmania infantum/genética , Leishmaniose Visceral/sangue , Leishmaniose Visceral/parasitologia , Masculino , Tipagem Molecular , Parasitemia/sangue , Parasitemia/parasitologia , Proteínas de Protozoários/genética , Análise de Sequência de DNARESUMO
Genotyping of sand fly species circulating in Peru was established on the basis of PCR-restriction fragment length polymorphisms (RFLPs) of the 18S ribosomal RNA (rRNA) gene. The sequences of 18S rRNA gene fragments from 12 Lutzomyia and 1 Warileya species were determined and their RFLP-patterns were analyzed. Consequently, RFLP analysis with the restriction enzyme AfaI and then HapII or KpnI, followed by XspI successfully differentiated them. Intraspecific genetic diversity affecting RFLP-patterns was not detected in the specimens collected from 24 areas of 8 departments. The genotyping was applied to the surveillance of sand flies collected from Andean areas where leishmaniasis is endemic, and its usability was verified. The present method promises to be a powerful tool for the classification and surveillance of sand flies circulating in Peru.
Assuntos
Doenças Endêmicas , Variação Genética , Leishmaniose/epidemiologia , Psychodidae/classificação , Psychodidae/genética , Animais , Genótipo , Humanos , Tipagem Molecular , Peru , Polimorfismo de Fragmento de Restrição , Psychodidae/crescimento & desenvolvimento , RNA Ribossômico 18S/genéticaRESUMO
A molecular epidemiological study was performed using FTA card materials directly sampled from lesions of patients with cutaneous leishmaniasis (CL) in the state of Lara, Venezuela, where causative agents have been identified as Leishmania (Viannia) braziliensis and L. (Leishmania) venezuelensis in previous studies. Of the 17 patients diagnosed with CL, Leishmania spp. were successfully identified in 16 patients based on analysis of the cytochrome b gene and rRNA internal transcribed spacer sequences. Consistent with previous findings, seven of the patients were infected with L. (V.) braziliensis. However, parasites from the other nine patients were genetically identified as L. (L.) mexicana, which differed from results of previous enzymatic and antigenic analyses. These results strongly suggest that L. (L.) venezuelensis is a variant of L. (L.) mexicana and that the classification of L. (L.) venezuelensis should be reconsidered.
Assuntos
Leishmania braziliensis/isolamento & purificação , Leishmania mexicana/isolamento & purificação , Leishmaniose Cutânea/enzimologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Genes de RNAr/genética , Humanos , Leishmania braziliensis/genética , Leishmania mexicana/genética , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/genética , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Reação em Cadeia da Polimerase , Especificidade da Espécie , Venezuela/epidemiologia , Adulto JovemRESUMO
The natural infection of sand flies by Leishmania species was studied in the Andean areas of Peru where cutaneous leishmaniasis caused by Leishmania (Viannia) peruviana is endemic. Sand flies were captured by human bait and Center for Disease Control (CDC) light trap catches at Nambuque and Padregual, Department of La Libertad, Peru, and morphologically identified. Among 377 female sand flies dissected, the two dominant man-biting species were Lutzomyia (Helcocyrtomyia) peruensis (211 flies) and Lutzomyia (Helcocyrtomyia) caballeroi (151 flies). Another sand fly species captured by light trap was Warileya phlebotomanica (15 flies). The natural infection of sand flies by flagellates was detected in 1.4% of Lu. (H.) peruensis and 2.6% of Lu. (H.) caballeroi, and the parasite species were identified as Le. (V.) peruviana and Trypanosoma avium, respectively, by molecular biological methods. The results indicated that the vector species responsible for the transmission of leishmaniasis in the study areas is Lu. (H.) peruensis. In addition, the presence of Trypanosoma in man-biting sand fly species means that more careful consideration is necessary for vector research in areas of Andean Peru where leishmaniasis is endemic.
Assuntos
Insetos Vetores/parasitologia , Leishmania/isolamento & purificação , Psychodidae/parasitologia , Trypanosoma/isolamento & purificação , Animais , Mordeduras e Picadas , Primers do DNA , Bases de Dados de Ácidos Nucleicos , Feminino , Humanos , Leishmania/genética , Leishmaniose/transmissão , Peru , Reação em Cadeia da Polimerase , Análise de Sequência , Trypanosoma/genéticaRESUMO
BACKGROUND: Determinants of the clinical presentation of the leishmaniases are poorly understood but Leishmania species and strain differences are important. To examine the relationship between clinical presentation, species and isoenzyme polymorphisms, 56 Leishmania isolates from distinct presentations of American tegumentary leishmaniasis (ATL) from Ecuador were analyzed. METHODS: Isolates were characterized by multilocus enzyme electrophoresis for polymorphisms of 11 isoenzymes. Patients were infected in four different ecologic regions: highland and lowland jungle of the Pacific coast, Amazonian lowlands and Andean highlands. RESULTS: Six Leishmania species constituting 21 zymodemes were identified: L. (Viannia) panamensis (21 isolates, 7 zymodemes), L. (V.) guyanensis (7 isolates, 4 zymodemes), L. (V.) braziliensis (5 isolates, 3 zymodemes), L. (Leishmania) mexicana (11 isolates, 4 zymodemes), L. (L.) amazonensis (10 isolates, 2 zymodemes) and L. (L.) major (2 isolates, 1 zymodeme). L. panamensis was the species most frequently identified in the Pacific region and was associated with several clinical variants of cutaneous disease (CL); eight cases of leishmaniasis recidiva cutis (LRC) found in the Pacific highlands were associated with 3 zymodemes of this species. Mucocutaneous leishmaniasis found only in the Amazonian focus was associated with 3 zymodemes of L. braziliensis. The papular variant of CL, Uta, found in the Andean highlands was related predominantly with a single zymodeme of L. mexicana. CONCLUSION: Our data show a high degree of phenotypic variation within species, and some evidence for associations between specific variants of ATL (i.e. Uta and LRC) and specific Leishmania zymodemes. This study further defines the geographic distribution of Leishmania species and clinical variants of ATL in Ecuador.
Assuntos
Isoenzimas/genética , Leishmania/enzimologia , Leishmaniose Cutânea/parasitologia , Adulto , Animais , Criança , Pré-Escolar , Equador , Feminino , Humanos , Leishmania/genética , Leishmania/isolamento & purificação , Masculino , Polimorfismo GenéticoRESUMO
Recently, two techniques, polymerase chain reaction (PCR) amplification and sequencing of cytochrome b gene (cyt b gene sequencing) and polymorphism-specific PCR (PS-PCR) were recommended for Leishmania species identification. Before this study, however, the accuracy of these methods had not been tested against the multilocus enzyme electrophoresis, the current gold standard technique on this task. Therefore, a trial was done for the first time to compare the results obtained by these techniques, using 17 Argentinean Leishmania stocks in independent assays. For all the stocks examined, the same results at species level were obtained by the three techniques. Among them, 14 were assigned to L. (Viannia) braziliensis, and three to L. (V.) guyanensis. The two techniques, cyt b gene sequencing and PS-PCR, were able to distinguish between all the proven species responsible for leishmaniases in Argentina. Thus, both techniques were validated and could be used independently for the species designation of Leishmania parasites in the country.
Assuntos
Citocromos b/genética , Leishmania/classificação , Reação em Cadeia da Polimerase/normas , Animais , Argentina , Sequência de Bases , Primers do DNA/química , Método Duplo-Cego , Eletroforese em Gel de Ágar , Leishmania/enzimologia , Leishmania/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Polimorfismo Genético , Reprodutibilidade dos Testes , Alinhamento de Sequência/métodos , Especificidade da EspécieRESUMO
BACKGROUND: Information regarding leishmaniasis recidiva cutis (LRC), a clinical variant of cutaneous leishmaniasis, in the New World is scarce. LRC is characterized by slowly progressing lesion(s) that appear after a variable period of time, from months to years, in or around the scar of an apparently clinically healed sore. PATIENTS AND METHODS: Six patients are reported who presented with crusted, papular lesions located on the edge of a healed scar, with a mean of 18.2 months of slowly progressive evolution. The isolated strains of Leishmania parasites were characterized by enzyme electrophoresis. Eleven enzyme systems were assayed. Skin biopsies from the active border of the lesions were taken for histopathology. RESULTS: Tissue sections showed a granulomatous, lymphohistiocytic, dermal infiltrate containing Langhans' giant cells. The anamnestic data, together with the clinical and histopathologic findings, support the diagnosis of LRC. The isoenzyme profile of Leishmania parasites isolated from five of the six patients identified them as Leishmania (Viannia) panamensis. CONCLUSIONS: These findings are the first reported evidence of LRC within the clinical spectrum of American tegumentary leishmaniasis in Ecuador, and of its causative agent. The existence of LRC has future implications for both disease treatment and vaccine development.
Assuntos
Leishmania guyanensis/enzimologia , Leishmania guyanensis/isolamento & purificação , Leishmaniose Mucocutânea/diagnóstico , Leishmaniose Mucocutânea/enzimologia , Adolescente , Adulto , Animais , Biópsia , Criança , Pré-Escolar , Equador , Eletroforese em Acetato de Celulose , Feminino , Humanos , Isoenzimas/isolamento & purificação , Masculino , Pele/patologia , Especificidade da Espécie , Clima TropicalRESUMO
Sixteen Leishmania stocks, 15 isolated from patients with cutaneous (CL), mucocutaneous (MCL), or recurrent cutaneous leishmaniasis, plus one from a dog with CL in Salta and Corrientes Provinces, Argentina, were studied by multilocus enzyme electrophoresis. Thirteen of the stocks from humans were grouped in two zymodemes; nine termed as KMS 1, four as KMS 2, and assigned to Leishmania (Viannia) braziliensis. Two additional stocks from CL cases expressed a KMS 4 enzyme profile, corresponding to L. (V.) guyanensis. Although the parasites from the dog were also assigned to L. (V.) braziliensis, its zymodeme, KMS 3, was not expressed in any of the current human isolates. The characterization of Leishmania from a dog was done for the first time in Argentina. The importance of the intraspecific polymorphism in the induction of clinical forms and in the host-reservoir concept is briefly discussed, based on the zymodeme data of isolates from humans and dogs. The presence of L. (V.) guyanensis was confirmed in the country.