[Show abstract][Hide abstract] ABSTRACT: The most severe clinical form of American tegumentary leishmaniasis (ATL) due to Leishmania braziliensis is mucosal leishmaniasis (ML), characterized by destructive lesions in the facial mucosa. We performed a retrospective cohort study of 109 ATL patients from Rio de Janeiro State, Brazil, where ATL is caused by Leishmania braziliensis, to evaluate the influence of intestinal parasite coinfections in the clinical course of ATL. Parasitological stool examination (PSE) was performed with samples from all patients by the sedimentation, Kato-Katz and Baermann-Moraes methods. The diagnosis of ATL was made from lesion biopsies by direct observation of amastigotes in Giemsa-stained imprints, isolation of Leishmania promastigotes or histopathological examination. All patients were treated with meglumine antimoniate. Patients with positive PSE had a frequency of mucosal lesions significantly higher than those with negative PSE (p < 0.005). The same was observed for infections with helminths in general (p < 0.05), with nematodes (p < 0.05) and with Ascaris lumbricoides (p < 0.05), but not for protozoan infections. Patients with intestinal parasites had poor response to therapy (therapeutic failure or relapse) significantly more frequently than the patients with negative stool examination (p < 0.005). A similar difference (p < 0.005) was observed between patients with positive and negative results for intestinal helminths, but not for intestinal protozoa. Patients with positive PSE took significantly longer to heal than those with negative PSE (p < 0.005). A similar difference was observed for intestinal helminth infections (p < 0.005), but not for protozoan infections. Our results indicate a deleterious influence of intestinal helminth infections in the clinical course of ATL and evidence for the first time an association between ML and these coinfections, particularly with nematodes and A. lumbricoides.
[Show abstract][Hide abstract] ABSTRACT: American visceral leishmaniasis is a vector-borne zoonosis in expansion in Brazil. Dogs are the main urban reservoir. Departing from a case of canine visceral leishmaniasis (CVL) in Jacaré, Niterói, Rio de Janeiro State, an epidemiological canine and entomological study was performed to assess the extension of the disease at the location. Sample was collected around the case and the dogs identified by serological tests (rapid double platform immunochromatographic exams, immunoenzymatic assay/ELISA, indirect immunofluorescence/IFAT). The parasitological diagnosis was performed in animals positive in at least one of these tests. The entomological study was carried out by using light traps and manual collection. The associations between canine variables and outcome (ELISA and IFAT reagents) were assessed by the chi-square test and adjusted by multivariate logistic regression for those associations with p < 0.1 in the bivariate analysis. Seventeen cases of CVL were detected among 110 evaluated dogs (prevalence of 15.5%). Presence of ectoparasites (OR 6.5; 95% CI 1.1-37.4), animals with clinical signs (OR 9.5; 95% CI 1.2-76.6), and previous cases of CVL in the same house (OR 17.9; 95% CI 2.2-147.1) were associated with the outcome. Lutzomyia longipalpiswas not detected. Our results are indicative of an ongoing transmission in the area.
Revista do Instituto de Medicina Tropical de São Paulo 09/2015; 57(4):325-332. DOI:10.1590/S0036-46652015000400009 · 1.01 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Neutrophil extracellular traps (NETs) have been described as a network of extracellular fibers composed by DNA, histones and various proteins/enzymes. Studies have demonstrated that NETs could be responsible for the trapping and elimination of a variety of infectious agents. In order to verify the presence of NETs in American tegumentary leish-maniasis (ATL) and their relationship with the presence of amastigotes we evaluated active cutaneous lesions of 35 patients before treatment by the detection of parasites, neutrophils (neutrophil elastase) and histones through immunohistochemistry and confo-cal immunofluorescence. Intact neutrophils could be detected in all ATL lesions. NETs were present in 27 patients (median 1.1; range from 0.1 to 23.5/mm 2) with lesion duration ranging from one to seven months. NETs were in close proximity with neutrophils (r = 0.586; p = 0.0001) and amastigotes (r = 0.710; p = 0.0001). Two patterns of NET formation were detected: small homogeneously distributed networks observed in all lesions; and large structures that could be visualized at a lower magnification in lesions presenting at least 20% of neutrophils. Lesions presenting the larger NET formation showed high parasite detection. A correlation between NET size and the number of intact amastigotes was observed (p=0.02). As we detected an association between NET and amastigotes, our results suggest that neutrophil migration and NET formation could be stimulated and maintained by stimuli derived from the parasite burden/parasite antigen in the extracellular environment. The observation of areas containing only antigens not intermingled with NETs (elastase and histone) suggests that the involvement of these structures in the control of parasite burden is a dynamic process in which the formation of NETs is exhausted with the destruction of the parasites. Since NETs were also associated with granulomas,
PLoS ONE 08/2015; 10(7). DOI:10.1371/journal.pone.0133063 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Introduction:
Trypanosoma caninum is a protozoan species recently described in dogs, whose occurrence has been reported in areas of overlap with visceral leishmaniasis.
Trypanosoma sp. were isolated from nine dogs and characterized by molecular methods.
PCR and sequencing confirmed the presence of T. caninum in all dogs, revealing two new areas of transmission: Barra Mansa and São João do Piauí.
The nine new cases described, when added to those already published, account for 62 cases of natural infection by T. caninum and show the geographical spread of this species to new areas, where other trypanosomatids circulate.
Revista da Sociedade Brasileira de Medicina Tropical 06/2015; 48(3):347-9. DOI:10.1590/0037-8682-0307-2014 · 0.98 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Canine visceral leishmaniasisis an important zoonosis caused by the protozoa Leishmania infantum (syn. Leishmania chagasi), whose clinical manifestationsare dependent on theimmune responseexpressed by the infected animal and the virulence of the parasite. Atypical clinical forms of canine visceral leishmaniasis have been reported.The purpose of this paper was to describe a tumor-like lesion form of canine visceral leishmaniasis and to alert clinical and pathologists veterinarians to the importance of its diagnosis. Amastigote forms were observed by cytopathological, histopathological and immunohistochemistry analysis from the tumour-like lesion and Leishmania infantum was isolated by culture from spleen, liver, lymph nodes and bone marrow samples. Clinical and pathologist veterinarians should include the canine visceral leishmaniasis in the differential diagnosis of tumors and chronic affections of oral mucosa, mainly in endemic regions of the disease.
[Show abstract][Hide abstract] ABSTRACT: This study evaluated the in vitro sensitivity of paired Leishmania braziliensis samples isolated from the same patient before pentavalent antimonial treatment (Sample A) and after treatment failure or cutaneous leishmaniasis reactivation (Sample B) in patients undergoing intralesional administration or injections (5 mgSb(V)/kg/d) of meglumine antimoniate. Fourteen samples from 7 patients were studied. After 24 h of drug exposure, 50% lethal dose (LD50) values for promastigotes ranged from 0.37 mg/mL to 5.86 mg/mL for samples obtained before treatment (A) and 0.89 mg/mL to 7.80 mg/mL for samples obtained after treatment (B). After 48 h, LD50 values ranged from 0.37 mg/mL to 5.75 mg/mL and 0.70 mg/mL to 7.68 mg/mL for A and B samples, respectively. After 48 h, LD50 values for amastigotes ranged from 11.7 to 44.3 μg/mL for A samples and 13.7 to 52.7 μg/mL for B samples. Of 7 patients, 1 discontinued treatment and 6 were cured after retreatment with amphotericin B (4 cases) or meglumine antimoniate (2 cases). Overall the B samples had higher LD50 values than A samples; however the difference was not significant. These results do not support the hypothesis that low-dose and intralesional treatments induce selection of resistant parasites in vitro and suggest that other factors may influence therapeutic outcome in patients with poor response to initial treatment.
[Show abstract][Hide abstract] ABSTRACT: Trypanosoma caninum is a parasite recently described in dogs, whose life cycle is rather unknown. Here, we performed a genetic study with T. caninum samples obtained in different Brazilian regions. The study was based on PCR assays target to small and large subunit ribosomal DNA (rDNA) (18S rDNA and 24Sα rDNA), cytochrome B (Cyt b), and internal transcribed spacer 1 rDNA (ITS1 rDNA) following by the sequence analysis. Additionally, we used primers for the variable regions of kinetoplast DNA (kDNA) minicircles and endonucleases restriction in the ITS1 rDNA amplification product. T. caninum samples displayed the same patterns. Tree construction confirmed the close relationship between T. caninum samples, regardless of the molecular target used and endonuclease restriction digestion revealed that all samples have the same restriction profile. Therefore, T. caninum seems to be a genetically homogeneous specie. In the kDNA assay, T. caninum possessed a different molecular size profile with respect to others trypanosomes, 330 and 350 bp. This study provides nucleotide sequences from different regions of the genome of T. caninum that certainly facilitate future studies.
Parasitology Research 01/2015; 114(2). DOI:10.1007/s00436-014-4291-0 · 2.10 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Introduction:
In Brazil, visceral leishmaniasis (VL) has spread to various regions. This study reports canine cases of VL in Barra Mansa, where human VL cases were recently reported.
Using the human index case, a canine survey was performed by dual-path platform immunochromatography and enzyme-linked immunosorbent assay. Seropositive animals were euthanized. Cultures were collected to detect Leishmania parasites.
Serological tests detected 141 canine VL cases, and Leishmania chagasi were isolated from 82.2% animals.
Leishmania chagasi is in circulation in Barra Mansa. This study broadens information on the parasite's distribution in the State of Rio de Janeiro.
Revista da Sociedade Brasileira de Medicina Tropical 12/2014; 47(6):788-90. DOI:10.1590/0037-8682-0042-2014 · 0.98 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Introduction: American tegumentary leishmaniasis (ATL) can affect the skin or mucosa (mucocutaneous leishmaniasis MCL) including the oral cavity. MCL oral lesions are often confused with other oral diseases, delaying diagnosis and specific treatment, and increasing the likelihood of sequelae. Thus, increasing the knowledge of the evolution of ATL oral lesions can facilitate its early diagnosis improving the prognosis of healing. Objectives: Evaluate the frequency of ATL oral lesion and describe its clinical, laboratory and therapeutic peculiarities. Methods: A descriptive transversal study was carried out, using data from medical records of 206 patients with MCL examined at the outpatient clinics-IPEC-Fiocruz between 1989 and 2013. Proportions were calculated for the categorical variables and the association among them was assessed by the Pearson's chi-square test. Measures of central tendency and dispersion were used for the continuous variables and their differences were assessed by both parametric (t test) and non parametric (Mann-Whitney) tests. P-values, <0.05 were considered as significant. Results: The most affected site was the nose, followed by the mouth, pharynx and larynx. Seventy eight (37.9%) have oral lesions and the disease presented a lower median of the evolution time than in other mucous sites as well as an increased time to heal. The presence of oral lesion was associated with: the presence of lesions in the other three mucosal sites; a smaller median of the leishmanin skin test values; a longer healing time of the mucosal lesions; a higher recurrence frequency; and a smaller frequency of treatment finishing and healing. When the oral lesion was isolated, it was associated with an age 20 years lower than when the oral lesion was associated with other mucosal sites. Conclusion: Considering the worst therapy results associated with the presence of oral lesions, we suggest that lesions in this location represent a factor of worse prognosis for MCL.
PLoS ONE 11/2014; 9(11):e109790. DOI:10.1371/journal.pone.0109790 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Trypanosoma caninum is a new species that has been recently identified in Brazil and infects domestic dogs. To date, no accurate diagnostic assays for this parasite have been established; thus, our aim was to evaluate more than one type of PCR for the diagnosis and molecular screening of T. caninum in 229 dogs living in Rio de Janeiro state. The tests were based on the amplification and sequencing of the 18S ribosomal DNA (rDNA) gene using healthy skin fragments. Additionally, PCR amplification of the kDNA minicircles region specific to the Leishmania genus was performed. The PCR results were compared with those of culture-based analysis performed with the same specimen. Using cultures, T. caninum and Leishmania chagasi were isolated from 11 and 12 dogs, respectively, whereas the 18S rDNA PCR assay detected parasitic infection in 35 dogs. Among these, 25 dogs showed an amplification pattern similar to T. caninum and 10 showed a pattern similar to L. chagasi; these results were confirmed by sequencing analysis. The kDNA PCR analysis showed that 14 dogs were positive for Leishmania infection. Of these, 2 dogs showed negative culture results and 12 were positive for L. chagasi, including 4 with negative 18S rDNA PCR results. Thus far, culture-based testing has been the only tool used successfully for T. caninum diagnosis. Our results demonstrate that 18S rDNA PCR-based test should be a useful diagnostic tool, particularly for distinguishing between T. caninum and L. chagasi infections in areas where these 2 parasites co-exist.
[Show abstract][Hide abstract] ABSTRACT: Representatives of the genus Trypanosoma have been traditionally found in epimastigote, espheromastigote and trypomastigote flagellated forms in axenic cultures. Trypanosoma caninum is a trypanosomatid that has recently been reported infecting dogs in endemic areas of canine leishmaniasis in Brazil. It presents specific biological characteristics and it is found exclusively on healthy skin. Here, we describe the evolutive forms of this parasite showing not only the forms commonly found in culture, but also epimastigote forms with no free flagellum. The study was conducted using scanning and transmission electron microscopy and, we demonstrate that typical flagellated epimastigotes originate from forms without flagellum, although the latter may remain without differentiation in the culture. Two hypotheses are considered and discussed in this paper: (i) the aflagellated epimastigotes are a typical developmental forms of T. caninum and (ii) the emergence of these aflagellated forms could be resultant from a disturbed process during cell division caused by interfering specific proteins, which leads to inability to form and regulate the flagellum length. In any case, considering that T. caninum is a parasite that is still little studied, the information brought by our study adds data which may be useful to clarify aspects on the cell cycle of this intriguing parasite that has been found in different regions of Brazil.
[Show abstract][Hide abstract] ABSTRACT: We report a case of a 42 year-old female, who came to a leishmaniasis
reference center in Rio de Janeiro, Brazil, presenting a cutaneous leishmaniasis
lesion in the right forearm. Treatment with low-dose intramuscular meglumine
antimoniate (MA) (5 mg Sb5+/kg/day) was initiated, with improvement after
28 days, although with the development of generalized eczema. After 87 days, the
lesion worsened. Patient refused treatment with amphotericin B. MA was then
infiltrated in the lesion, in two sessions, resulting in local eczema, with bullae
formation; however, twenty days after, both the ulcer and eczema receded.
Intralesional administration of MA should be used carefully when previous cutaneous
hypersensitivity is detected.
Revista do Instituto de Medicina Tropical de São Paulo 07/2014; 56(4):361-2. DOI:10.1590/S0036-46652014000400016 · 1.01 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Introduction:
During a diagnostic evaluation of canine visceral leishmaniasis (VL), two of seventeen dogs were found to be co-infected by Leishmania (Viannia) braziliensis and Leishmania (Leishmania) chagasi.
Specific polymerase chain reaction (PCR) and restriction fragment length polymorphism-PCR (RFLP-PCR) assays were performed.
PCR assays for Leishmania subgenus identification followed by RFLP-PCR analysis in biopsies from cutaneous lesions and the spleen confirmed the presence of Leishmania (Viannia) braziliensis and Leishmania (Leishmania) chagasi in those fragments.
This report reinforces the importance of using serological and molecular techniques in the epidemiological surveillance of canine populations in endemic areas in which both diseases are known to co-exist. In such cases, a reassessment of the control measures is required.
Revista da Sociedade Brasileira de Medicina Tropical 04/2014; 47(2):243-6. DOI:10.1590/0037-8682-0007-2013 · 0.98 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Abstract Trypanosoma caninum constitutes the most recent trypanosomatid species infecting dogs in Brazil. Due to the limited data available about this parasite, this study aims to disclose clinical and laboratory findings from 14 dogs naturally infected. The dogs were diagnosed during a cross-sectional survey in Cuiabá (Mato Grosso, Brazil) and followed-up at interval of 3, 6 and 12 mo in order to evaluate the clinical evolution, and to investigate the parasite and/or DNA in different biological samples (intact skin, cutaneous scar, blood, bone marrow and lymph node aspirate) by parasitological (culture and smear exam) and molecular (DNA-based tests) methods. Specific anti-T. caninum and anti-Leishmania antibody production was also evaluated. Ten of 14 dogs infected by T. caninum showed a good general state at the time of diagnosis, and this status did not vary during the follow-up. Anti-T. caninum and anti-Leishmania IgG antibodies were detected by IFAT in 10 and 2 animals, respectively. Concomitant infection by Leishmania chagasi was confirmed in 2 dogs, evidencing the overlap of endemic areas in Cuiabá. Our results indicate that T. caninum infection can be manifested as asymptomatic case with low humoral immune response. Furthermore, despite examination of several biological samples, T. caninum (parasite or DNA) was found only in the intact skin in all animals.
Journal of Parasitology 12/2013; 100(2). DOI:10.1645/13-297.1 · 1.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In Brazil, American visceral leishmaniasis (AVL) is caused by Leishmania (Leishmania) chagasi and its main vector is Lutzomyia longipalpis. Cases of canine visceral leishmaniasis (CVL) in non-endemic areas have been reported over the last few years throughout the country. The objective of this research note is to describe an autochthonous case of CVL that occurred in the municipality of Volta Redonda, state of Rio de Janeiro, an area where the disease is not endemic, alerting veterinarians and the scientific community to the expansion of this important zoonosis and advising veterinary practitioners on how to deal with a suspicion of CVL. Canine visceral leishmaniasis can be misdiagnosed within a broad spectrum of canine diseases based on clinical and laboratory findings. Therefore, knowledge of its clinical manifestations, specific and sensitive laboratory diagnostic tests and parasitological procedures are of the utmost importance for rapid confirmation and notification of a case, thus contributing directly to the control of a focus.
Revista brasileira de parasitologia veterinaria = Brazilian journal of veterinary parasitology: Orgao Oficial do Colegio Brasileiro de Parasitologia Veterinaria 10/2013; 22(3):424-426. DOI:10.1590/S1984-29612013000300018 · 0.87 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Trypanosoma cruzi, infecta cerca de 10 milhões de pessoas, principalmente na América Latina e mais de 25 milhões apresentam-se em risco de adquirir a doença nas áreas endêmicas. Os cães são considerados importantes reservatórios representando fator de risco para a população humana. Este relato descreve caso de doença de Chagas em cão na cidade de Cuiabá. O diagnóstico foi feito a partir do exame direto, apresentando inúmeras formas tripomastigotas em esfregaço sanguíneo. Amastigotas foram visualizadas na microscopia de medula óssea, linfonodo, rins, fígado e cérebro. A infecção por T. cruzi (ZIII) foi confirmado através do sequenciamento de produtos amplificados pela PCR. O animal apresentou sinais multissistêmicos, evoluindo para óbito. Apesar da doença de Chagas aguda em humanos não ser descrita em Cuiabá, este é o primeiro relato de um caso canino nessa região, fato que, constitui alerta aos profissionais da saúde e autoridades sanitárias para a possibilidade da transmissão desta zoonose em Cuiabá.
Revista do Instituto de Medicina Tropical de São Paulo 07/2013; 55(4):287-289. DOI:10.1590/S0036-46652013000400011 · 1.01 Impact Factor