César Augusto Cuba

Human mucocutaneous leishmaniasis in Três Braços, Bahia - Brazil: an area of Leishmania braziliensis braziliensis transmission. II. Cutaneous disease. Presentation and evolution

Foram analisados os dados clinicos de 182 pacientes com leishmaniose cutânea, provavelmente causada por Leishmania braziliensis braziliensis. Sessenta e oito por cento apresentavam uma unica lesao, usualmente uma ulcera, na terca parte inferior anterior da tibia. Todos os grupos etarios estavam representados e muitos apresentaram historico de um a dois meses. Treze por cento apresentavam lesoes fechadas de natureza verrucosa ou em placa. Apos tratamento, a evolucao destas lesoes foi relacionada a regularidade da terapia por antimonio. Embora a cura usualmente ocorresse em tres meses, o tempo de cicatrizacao, apos o inicio de tratamento, foi variavel e relativo ao tamanho da lesao (p < 0.01). Em geral a lesao fechava quando era dado suficiente antimonio como tratamento. Sete entre dez pacientes que apresentavam teste cutâneo negativo para leishmania tomavam positivos apos o tratamento. Observou-se por fluorescencia indireta, um declinio significante nos titulos de anticorpos em pacientes acompanhados durante e apos a terapia.

Trypanosoma cruzi I genotypes in different geographical regions and transmission cycles based on a microsatellite motif of the intergenic spacer of spliced-leader genes.

The intergenic region of spliced-leader (SL-IR) genes from 105 Trypanosoma cruzi I (Tc I) infected biological samples, culture isolates and stocks from 11 endemic countries, from Argentina to the USA were characterised, allowing identification of 76 genotypes with 54 polymorphic sites from 123 aligned sequences. On the basis of the microsatellite motif proposed by Herrera et al. (2007) to define four haplotypes in Colombia, we could classify these genotypes into four distinct Tc I SL-IR groups, three corresponding to the former haplotypes Ia (11 genotypes), Ib (11 genotypes) and Id (35 genotypes); and one novel group, Ie (19 genotypes). Genotypes harbouring the Tc Ic motif were not detected in our study. Tc Ia was associated with domestic cycles in southern and northern South America and sylvatic cycles in Central and North America. Tc Ib was found in all transmission cycles from Colombia. Tc Id was identified in all transmission cycles from Argentina and Colombia, including Chagas cardiomyopathy patients, sylvatic Brazilian samples and human cases from French Guiana, Panama and Venezuela. Tc Ie gathered five samples from domestic Triatoma infestans from northern Argentina, nine samples from wild Mepraia spinolai and Mepraia gajardoi and two chagasic patients from Chile and one from a Bolivian patient with chagasic reactivation. Mixed infections by Tc Ia+Tc Id, Tc Ia+Tc Ie and Tc Id+Tc Ie were detected in vector faeces and isolates from human and vector samples. In addition, Tc Ia and Tc Id were identified in different tissues from a heart transplanted Chagas cardiomyopathy patient with reactivation, denoting histotropism. Trypanosoma cruzi I SL-IR genotypes from parasites infecting Triatoma gerstaeckeri and Didelphis virginiana from USA, T. infestans from Paraguay, Rhodnius nasutus and Rhodnius neglectus from Brazil and M. spinolai and M. gajardoi from Chile are to our knowledge described for the first time.

Características epidemiológicas da leishmaniose tegumentar americana em uma região endêmica do Estado da Bahia: III. Fauna flebotomínica

The phlebotomine fauna is highly varied in tres Bracos, an endemic area american cutaneous leishmaniasis, situated in the cacao growing region in the southeast of Bahia State, brazil. Thirty species of the Lutzomyia genus were identified in 13,535 spcecimens collected between 1976 and 1984. Lutzomyia whitmani was the dominant species accounting for 99% or flies in the periodomicile and 97.5% of those caught in homes. In the forest the predominant species were Lu. ayrozai and Lu. yulli. Lu whitmani accounted for only 1.0% of the specimens examined. Lu. flaviscutellata, the proven vector of Leishmania mexicana amazonensis, was also collected in small numbers, I.u. wellcomei, a known vector of L. braziliensis braziliensis in the Serra dos Carajas, Para, Brazil was not encountered in the Tres Bracos region where the parasite causing human infections is usually L.b. braziliensis. Although we have not encountered a natural infection with leishmanial promastigotes in 1.832 females of the various species examined, we discuss the probability that Lu. whitmani is the vector of L.b braziliensis in the region mantaining transmission in dogs and man.

The Triatomines of Northern Peru, with Emphasis on the Ecology and Infection by Trypanosomes of Rhodnius ecuadoriensis (Triatominae)

Information on the distribution and synanthropic behaviour of triatomines is essential for Chagas disease vector control. This work summarises such information from northern Peru, and presents new data on Rhodnius ecuadoriensis - an important local vector infesting 10-35% of dwellings in some zones. Three species are strongly synanthropic and may be suitable targets for chemical control of domestic/peridomestic bug populations. Panstrongylus herreri, the main domestic vector in the area, is probably present in sylvatic ecotopes in the Marañón river system. R. ecuadoriensis and Triatoma dimidiata seem exclusively domestic; biogeographical and ecological data suggest they might have spread in association with humans in northern Peru. Confirmation of this hypothesis would result in a local eradication strategy being recommended. Presence of trypanosome natural infection was assessed in 257 R. ecuadoriensis; Trypanosoma rangeli was detected in 4% of bugs. Six further triatomine species are potential disease vectors in the region (T. carrioni, P. chinai, P. rufotuberculatus, P. geniculatus, R. pictipes, and R. robustus), whilst Eratyrus mucronatus, E. cuspidatus, Cavernicola pilosa, Hermanlentia matsunoi, and Belminus peruvianus have little or no epidemiological significance. A strong community-based entomological surveillance system and collaboration with Ecuadorian public health authorities and researchers are recommended.

Histopatologia da leishmaniose tegumentar por Leishmania braziliensis braziliensis: 1. Padrões histopatológicos e estudo evolutivo das lesões

The Authors describe the histopathological findings observed in biopsies from 378 cases of Mucocutaneous Leishmaniasis, caused by Leishmania braziliensis braziliensis. All the patients lived in the locality of Tres Bracos, State of Bahia, an endemic area of Leishmaniasis in Brazil. Parasites were found in 63.7% of patients with cutaneous form and in 35.7% of cases with mucous lesions, although always in reduced number. Histopathologic findings allowed the caracterization of five different patterns: 1. Exsudative-cellular reaction, due to infiltraction of histiocytes, lymphocytes and plasm cells; 2. Exsudative-necrotic reaction, characterized by the association of necrosis with cellular infiltration; 3. Exsudative and necrotic-granulomatous reaction, corresponding to pattern described as chronic-granulomatous inflammation with necrosis; 4. Exsudativegranulomatous reaction, characterized a disorganized granulomatous reaction, without tissue necrosis; 5. Exsudative-tuberculoid reaction — in which a typical tuberculoid granuloma is formed. The follow-up study in 49 patients showed, in sucessive biopsies, changes in the histopathologic patterns in 63.2% of cutaneous forms and in 45.4% of the mucous forms. It was concluded that the exsudative-cellular reaction represents both the inicial and final pattern of Mucocutaneous Leishmaniasis lesion. The other four histopathologic patterns characterize intermediate forms found during the evolution of the disease.

Leishmaniose mucocutânea humana em Três Braços, Bahia - Brasil: uma área de transmissão de Leishmania braziliensis braziliensis. III. Comprometimento mucoso e evolução inicial

In an analysis of 57 patients mucosal disease was commonestin males(77%) in the third decade of life although the age range was wide and even two children were affected. All but nine patients (16%) had signs of cutaneous leishmaniasis but in only 8(14%) was this lesion active. The nose was affected in 100% of 19 patients with multiple lesions and 92% of 38 patients with single lesions. The pharynx, palate, larynx and upper lip were affected in this order. 42% of patients with multiple lesions had laryngeal disease and in two patients this site existed as a lone lesion. No age difference could be discemed as to whether lesions were single or multiple. Duration of mucosal disease was very variable from less than 4 months to 264 months. Only 7% developed mucosal disease more than ten years after the cutaneous lesion. Usually patients responded to adequate antimonial treatment but there were exceptions, when amphotericin B had to be used Three patients who refused to collaborate regarding treatment died Only 18% of patients in whom measurements were made had positive fluorescent antibodies two years after treatment.

Revisión de los aspectos biológicos y diagnósticos del Trypanosoma (Herpetosoma) rangeli

Resumen Esta revision tiene tres objetivos basicos: a) estimular aun mas la investigacion de estaprevalente infeccion humana. b) examinar el arsenal de tecnicas diagnosticas disponibles almomento y, las nuevas pruebas descritas recientemente. c) enfatizar el significado que tiene, elparasitismo por el Trypanosoma (Herpetosoma) rangeli, en las areas endemicas de laEnfermedad de Chagas distribuidas en las Americas Central y del Sur. Trypanosoma rangeli yTrypanosoma cruzi son parasitos que circulan superponiendose en muchas areas deLatinoamerica utilizando practicamente los mismos triatominos vectores. Una vasta gama deespecies de mamiferos han sido encontradas infectadas naturalmente con T. rangeli en diversospaises. Se revisa la biologia del parasitismo y el ciclo biologico del tripanosoma haciendo enfasisen este ultimo. Infecciones cronicas por T. rangeli en el hombre pueden, serologicamente, serconfundidas con las del T. cruzi. Ambas especies presentan antigenos comunes que provocanlas conocidas reacciones serologicas cruzadas. Desafortunadamente, no conocemos la realdistribucion de las infecciones por el T. rangeli en la mayoria de las areas mencionadas. Nuevosestudios epidemiologicos son necesarios, para examinar el problema de las infecciones humanasmixtas, por estos tripanosomas.Palabras-claves: Trypanosoma (Herpetosoma) rangeli. Biologia. Epidemiologia. Diagnostico.207

Human mucocutaneous leishmaniasis in Tres Bracos. Bahia - Brazil. An area of Leishmania braziliensis braziliensis transmission. I. Laboratory diagnosis.

Leishmanial parasites were detected in 71.2% of patients with cutaneous disease and 48% of patients with mucosal disease, using principally scanning of imprints mears and histological sections and hamster inoculation. Parasites were more frequent in early cutaneous lesions (p < 0.005) o fless than two month duration. Also they were more common in multiple than single mucosal lesions (p < 0.02) in spite of considerable prior glucan time therapy in the former group. 93% of cutaneous lesions had a positive leishmanin skin test and most of the negatives occurred in patients with lesions of less than one month duration. 97% of patients with single mucosal lesion and 79% with multiple mucosal lesions had a positive skin test. 86% of cutaneous disease and 90% of mucosal disease was associated with a positive indirect immunofluorescent antibody test at a ≥ 1/20 dilution. In both groups multiple lesions were associated with higher titres and titres were significantly higher in patients with mucosal disease compared with cutaneous disease (p < 0.01).

Multiplex Real-Time PCR Assay Using TaqMan Probes for the Identification of Trypanosoma cruzi DTUs in Biological and Clinical Samples

Background Trypanosoma cruzi has been classified into six Discrete Typing Units (DTUs), designated as TcI–TcVI. In order to effectively use this standardized nomenclature, a reproducible genotyping strategy is imperative. Several typing schemes have been developed with variable levels of complexity, selectivity and analytical sensitivity. Most of them can be only applied to cultured stocks. In this context, we aimed to develop a multiplex Real-Time PCR method to identify the six T. cruzi DTUs using TaqMan probes (MTq-PCR). Methods/Principal Findings The MTq-PCR has been evaluated in 39 cultured stocks and 307 biological samples from vectors, reservoirs and patients from different geographical regions and transmission cycles in comparison with a multi-locus conventional PCR algorithm. The MTq-PCR was inclusive for laboratory stocks and natural isolates and sensitive for direct typing of different biological samples from vectors, reservoirs and patients with acute, congenital infection or Chagas reactivation. The first round SL-IR MTq-PCR detected 1 fg DNA/reaction tube of TcI, TcII and TcIII and 1 pg DNA/reaction tube of TcIV, TcV and TcVI reference strains. The MTq-PCR was able to characterize DTUs in 83% of triatomine and 96% of reservoir samples that had been typed by conventional PCR methods. Regarding clinical samples, 100% of those derived from acute infected patients, 62.5% from congenitally infected children and 50% from patients with clinical reactivation could be genotyped. Sensitivity for direct typing of blood samples from chronic Chagas disease patients (32.8% from asymptomatic and 22.2% from symptomatic patients) and mixed infections was lower than that of the conventional PCR algorithm. Conclusions/Significance Typing is resolved after a single or a second round of Real-Time PCR, depending on the DTU. This format reduces carryover contamination and is amenable to quantification, automation and kit production.

Enzootic transmission of Trypanosoma cruzi and T. rangeli in the Federal District of Brazil

The Federal District of Brazil (DF) lies within the Cerrado biome, where open shrubland (savannas) is interspersed with riverside gallery forests and permanent swamps (veredas). Trypanosoma cruzi-infected native triatomines occur in the area, but the enzootic transmission of trypanosomatids remains poorly characterized. A parasitological survey involving sylvatic triatomines (166 Rhodnius neglectus collected from Mauritia flexuosa palms) and small mammals (98 marsupials and 70 rodents, totaling 18 species) was conducted in 18 sites (mainly gallery forests and veredas) of the DF. Parasites were isolated, morphologically identified, and characterized by PCR of nuclear (mini-exon gene) and kinetoplast DNA (kDNA). Six R. neglectus, seven Didelphis albiventris and one Akodon cursor were infected by trypanosomes; wild reservoir infection is documented for the first time in the DF. kDNA PCR detected T. cruzi in five R. neglectus and mini-exon gene PCR revealed T. cruzi I in isolates from D. albiventris. Parasites infecting one bug yielded T. rangeli KP1+ kDNA amplicons. In spite of the occurrence of T. cruzi-infected D. albiventris (an important wild and peridomestic reservoir) and R. neglectus (a secondary vector displaying synanthropic behavior), a low-risk of human Chagas disease transmission could be expected in the DF, considering the low prevalence infection recorded in this work. The detection of T. rangeli KP1+ associated with R. neglectus in the DF widens the known range of this parasite in Brazil and reinforces the hypothesis of adaptation of T. rangeli populations (KP1+ and KP1-) to distinct evolutionary Rhodnius lineages.