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.

Febre crônica associada a abscesso esplênico causado por Staphylococcus epidermidis

Abscessos ocultos são causa freqüente de febre crônica. Os abscessos esplênicos são entidades raras, usualmente associadas a quadros subjacentes de cirurgia abdominal, endocardite ou imunodepressão. Apresenta-se um caso de paciente com febre prolongada causada por um abscesso esplênico, cujo principal diagnóstico diferencial era leishmaniose visceral, que provavelmente esteve associado a traumatismo abdominal. O tratamento consistiu em antibioticoterapia seguida de esplenectomia.

Efeito de uma formulação hidrofílica de paromomicina tópica na leishmaniose cutânea em pacientes com contra-indicações de tratamento com antimonial pentavalente

Descrevem-se o efeito terapêutico e os eventos adversos associados com o uso tópico de paromomicina 10% em gel na leishmaniose cutânea. Quinze pacientes com leishmaniose cutânea cumpriram os critérios de inclusão descritos a seguir: contra-indicação para o uso de antimoniato de meglumina, intradermorreação de Montenegro positiva e até quatro lesões ulceradas. A fórmula foi prescrita duas vezes ao dia por 20 dias. Quatorze pacientes estiveram disponíveis para a avaliação do desfecho terapêutico e a proporção de cura foi de 21,4% (3/14), 50% melhoraram até a epitelização completa e a proporção de falha foi de 28,6%. Nove pacientes que não apresentaram cura inicialmente foram re-tratados. Oito receberam uma nova série de paromomicina tópica e um foi tratado com antimoniato de meglumina. Dois pacientes não receberam novo tratamento e tiveram melhora lenta e contínua. Cinco de oito pacientes retratados com paromomicina tópica alcançaram a cura clínica, e três apresentaram falha, incluindo um paciente que tinha apresentado melhora com o primeiro tratamento. Os eventos adversos foram leves e locais em 53,3% dos pacientes e nunca levaram à suspensão do tratamento.

Autochthonous visceral leishmaniasis in Brasília, Federal District, Brazil

INTRODUCTION: Visceral leishmaniasis is a public health threat in Brazil considering the high lethality rates and increasing geographical dispersion to large urban conglomerates over the past 25 years. This study aimed to confirm suspected autochthonous cases of visceral leishmaniasis reported from 2005 to 2009 among individuals living in Brasilia, Federal District. METHODS: A retrospective review of the surveillance data obtained on a regular basis and clinical records of the reported cases were performed in 2009. RESULTS: Data from entomological and canine surveys revealed the presence of both Lutzomyia longipalpis and positive serology for Leishmania in dogs within 19 of the 21 neighborhoods where human cases occurred since 2005. The review of surveillance data and medical records, together with the entomological and canine survey data, permitted confirmation of 21 autochthonous human cases in the Federal District. The disease predominantly affected children (12/21) and those from the Sobradinho region (16/21); the typical presentation of fever, hepatosplenomegaly and pancytopenia was observed in 67% of cases. Three deaths occurred during the study period. Leishmania (Leishmania) chagasi was successfully isolated from one human case and twelve canine cases. CONCLUSIONS: Visceral leishmaniasis should be considered endemic in Brasilia based on the documented epidemiological behavior herein described and the confirmed autochthony of human cases.

Genus-specific kinetoplast-DNA PCR and parasite culture for the diagnosis of localised cutaneous leishmaniasis: applications for clinical trials under field conditions in Brazil

The positivities of two methods for the diagnosis of localised cutaneous leishmaniasis (CL) were estimated in 280 patients enrolled in a clinical trial. The trial was conducted in an endemic area of Leishmania (Viannia) braziliensis and trial participants were patients with skin ulcers and positive leishmanin skin tests. Patients underwent aspirative skin punctures of the ulcerated lesions and lymph nodes for in vitro cultures, which were processed under field conditions at the local health centre. Skin lesion biopsies were tested at a reference laboratory using kinetoplastid DNA (kDNA)-PCR to detect DNA. The median time required to obtain a positive culture from the skin samples was seven days and the contamination rate of the samples was 1.8%. The positivities of the cultures from skin lesions, kDNA-PCR and the combination of the two methods were 78.2% (95% CI: 73-82.6%), 89.3% (95% CI: 85.1-92.4%) and 97.1% (95% CI: 94.5-98.5%). We conclude that parasite culture is a feasible method for the detection of Leishmania in field conditions and that the combination of culture and PCR has a potential role for the diagnosis of CL in candidates for clinical trials.

The identification of two Trypanosoma cruzi I genotypes from domestic and sylvatic transmission cycles in Colombia based on a single polymerase chain reaction amplification of the spliced-leader intergenic region

A single polymerase chain reaction (PCR) reaction targeting the spliced-leader intergenic region of Trypanosoma cruzi I was standardised by amplifying a 231 bp fragment in domestic (TcIDOM) strains or clones and 450 and 550 bp fragments in sylvatic strains or clones. This reaction was validated using 44 blind coded samples and 184 non-coded T. cruzi I clones isolated from sylvatic triatomines and the correspondence between the amplified fragments and their domestic or sylvatic origin was determined. Six of the nine strains isolated from acute cases suspected of oral infection had the sylvatic T. cruzi I profile. These results confirmed that the sylvatic T. cruzi I genotype is linked to cases of oral Chagas disease in Colombia. We therefore propose the use of this novel PCR reaction in strains or clones previously characterised as T. cruziI to distinguish TcIDOMfrom sylvatic genotypes in studies of transmission dynamics, including the verification of population selection within hosts or detection of the frequency of mixed infections by both T. cruzi I genotypes in Colombia.

Accuracy of mucocutaneous leishmaniasis diagnosis using polymerase chain reaction: systematic literature review and meta-analysis

The diagnosis of mucocutaneous leishmaniasis (MCL) is hampered by the absence of a gold standard. An accurate diagnosis is essential because of the high toxicity of the medications for the disease. This study aimed to assess the ability of polymerase chain reaction (PCR) to identify MCL and to compare these results with clinical research recently published by the authors. A systematic literature review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses: the PRISMA Statement was performed using comprehensive search criteria and communication with the authors. A meta-analysis considering the estimates of the univariate and bivariate models was performed. Specificity near 100% was common among the papers. The primary reason for accuracy differences was sensitivity. The meta-analysis, which was only possible for PCR samples of lesion fragments, revealed a sensitivity of 71% [95% confidence interval (CI) = 0.59; 0.81] and a specificity of 93% (95% CI = 0.83; 0.98) in the bivariate model. The search for measures that could increase the sensitivity of PCR should be encouraged. The quality of the collected material and the optimisation of the amplification of genetic material should be prioritised.

Effect of GA3, KNO3, and removing of basal point of seeds on germination of sweet granadilla (Passiflora ligularis Juss) and yellow passion fruit (Passiflora edulis f. flavicarpa)

Passiflora seeds germinate erratically presenting difficulties for their handling in a greenhouse. The effect of removing of basal point of seeds (RB) and pre-imbibition of seeds of sweet granadilla and yellow passion fruit in 50, 100, 200, and 400 mg mL-1 solutions of gibberellic acid (GA3) or 0.1% KNO3 solution was studied. The experiment was conducted in greenhouses in La Plata, Colombia. Two accessions PrJ1 and PrJ2 of sweet granadilla were evaluated. There were calculated the final percentage of germination (PG), mean germination time (MGT), and the mean germination rate (MGR). The leaf area and dry mass of seedlings were measured 22 days after sowing (das); with this data, specific leaf area and relation root/shoot were calculated. In all cases, the highest germination percentages were achieved treating seeds with KNO3 (89, 92, and 87% for yellow passion fruit, PrJ2, and PrJ1, respectively), but the increase in MGR (3.3 germinated seeds per day) and the decrease in MGT (16 days) were only significant for PrJ1. RB had a significant reduction of PG in all cases (28, 12, and 33% for passion fruit, PrJ2 and PrJ1, respectively). With the increase in the concentration of GA3, PG was reduced for two accessions of sweet granadilla, for yellow passion fruit this trend was not clear, no treatment with GA3 showed significant differences with the control. Leaf area (24.07 cm2) and dry mass of seedlings (135 mg) were significantly higher than seeds previously treated with KNO3 only for PrJ1.The solution of KNO3 0,1% is recommended to improve the germination and initial growth of granadilla seedlings.

Acetic acid as an intervention strategy to decontaminate beef carcasses in mexican commercial slaughterhouse

Beef can be contaminated during the slaughter process, thus other methods, besides the traditional water washing, must be adopted to preserve meat safety. The objective of this study was to evaluate the effect of 2% acetic acid interventions on the reduction of indicator bacteria on beef carcasses at a commercial slaughterhouse in Mexico. Reduction was measured by the count of mesophilic aerobic bacteria (TPC), total coliform (TC), and fecal coliform (FC) (log CFU/ cm²). Among the different interventions tested, treatments combining acetic acid solution sprayed following carcass water washing had greater microbial reduction level. Acetic acid solution sprayed at low pressure and longer time (10-30 psi/ 60 s) reached higher TPC, TC, and FC reductions than that obtained under high pressure/ shorter time (1,700 psi/ 15 s; P<0.05). Exposure time significantly affected microbial reduction on carcasses. Acetic acid solution sprayed after carcass washing can be successfully used to control sources of indicator bacteria on beef carcasses under commercial conditions.