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1.
Acta Trop ; 250: 107092, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38065375

RESUMO

Leishmaniases are zoonotic diseases caused by protozoa of the genus Leishmania. In Bolivia, leishmaniasis occurs mainly in the cutaneous form (CL) followed by the mucosal or mucocutaneous form (ML or MCL), grouped as tegumentary leishmaniosis (TL), while cases of visceral leishmaniasis (VL) are rare. The cases of TL are routinely diagnosed by parasitological methods: Direct Parasitological Exam (DPE) and axenic culture, the latter being performed only by specialized laboratories. The aim of the present study was to optimize the parasitological diagnosis of TL in Bolivia, using two sampling methods. Samples from 117 patients with suspected TL, obtained by aspiration (n = 121) and scraping (n = 121) of the edge of the lesion were tested by: direct parasitological exam, culture in TSTB medium, and miniculture and microculture in Schneider's medium. A positive laboratory result by any of the four techniques evaluated using either of the two sampling methods was considered the gold standard. Of the 117 suspected patients included, TL was confirmed in 96 (82 %), corresponding 79 of the confirmed cases (82.3 %) to CL and 16 (16.7 %) to ML. Parasitological techniques specificity was 100 % and their analytical sensitivity was greater with scraping samples in TSTB culture (98 %). Scraping samples in TSTB and miniculture correlated well with the reference (Cohen's kappa coefficient=0.88) and showed good reliability (Cronbach's alpha coefficient ≥0.91). Microculture provided positive results earlier than the other culture methods (mean day 4.5). By day 14, 98 % of positive cultures had been detected. Scraping sampling and miniculture were associated with higher culture contamination (6 % and 17 %, respectively). Bacterial contamination predominated, regardless of the sampling and culture method, while filamentous fungi and mixed contamination were more frequently observed in cultures from scraping samples. In conclusion: (i) scraping samples proved more suitable for the diagnosis of TL as they increased analytical sensitivity, are less traumatic for the patient and are safer for laboratory personnel than aspirates; (ii) culture, mainly in TSBT medium, should be used for the diagnosis of TL due to its high sensitivity (doubling the number of cases diagnosed by DPE) and its low cost compared to other culture media.


Assuntos
Leishmania , Leishmaniose Cutânea , Leishmaniose Visceral , Leishmaniose , Humanos , Bolívia , Reprodutibilidade dos Testes , Leishmaniose/diagnóstico , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/parasitologia , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/parasitologia
2.
Carbohydr Res ; 536: 109015, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38198982

RESUMO

The protozoan parasite Leishmania (Viannia) braziliensis is among Latin America's most widespread Leishmania species and is responsible for tegumentary leishmaniasis (TL). This disease has multiple clinical presentations, with cutaneous leishmaniasis (CL) being the most frequent. It manifests as one or a few localized skin ulcers, which can spread to other body areas. Hence, early diagnosis and treatment, typically with pentavalent antimonials, is critical. Traditional diagnostic methods, like parasite culture, microscopy, or the polymerase chain reaction (PCR) for detection of the parasite DNA, have limitations due to the uneven distribution of parasites in biopsy samples. Nonetheless, studies have revealed high levels of parasite-specific anti-α-Gal antibodies in L. (V.) braziliensis-infected patients. Previously, we demonstrated that the neoglycoprotein NGP28b, consisting of the L. (Leishmania) major type-2 glycoinositolphospholipid (GIPL)-3-derived trisaccharide Galpα1,6Galpα1,3Galfß conjugated to bovine serum albumin (BSA) via a linker, acts as a reliable serological biomarker (BMK) for L. (V.) braziliensis infection in Brazil. This indicates the presence of GIPL-3 or a similar structure in this parasite, and its terminal trisaccharide either functions as or is part of an immunodominant glycotope. Here, we explored whether extending the trisaccharide with a mannose unit would enhance its efficacy as a biomarker for the serological detection of L. (V.) braziliensis. We synthesized the tetrasaccharide Galpα1,6Galpα1,3Galfß1,3Manpα(CH2)3SH (G31SH) and conjugated it to maleimide-functionalized BSA to afford NGP31b. When we assessed the efficacy of NGP28b and NGP31b by chemiluminescent enzyme-linked immunosorbent assay on a cohort of CL patients with L. (V.) braziliensis infection from Bolivia and Argentina against a healthy control group, both NGPs exhibited similar or identical sensitivity, specificity, and accuracy. This finding implies that the mannose moiety at the reducing end is not part of the glycotope recognized by the parasite-specific anti-α-Gal antibodies in patients' sera, nor does it exert a relevant influence on the terminal trisaccharide's conformation. Moreover, the mannose does not seem to inhibit glycan-antibody interactions. Therefore, NGP31b is a viable and dependable BMK for the serodiagnosis of CL caused by L. (V.) braziliensis.


Assuntos
Leishmania braziliensis , Leishmaniose Cutânea , Humanos , Leishmania braziliensis/genética , Manose , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/tratamento farmacológico , Glicoproteínas , Trissacarídeos
3.
Pathogens ; 12(9)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37764911

RESUMO

Activated monocytes/macrophages that produce inflammatory cytokines and nitric oxide are crucial for controlling Trypanosoma cruzi infection. We previously showed that uninfected newborns from T. cruzi infected mothers (M+B- newborns) were sensitized to produce higher levels of inflammatory cytokines than newborns from uninfected mothers (M-B- newborns), suggesting that their monocytes were more activated. Thus, we wondered whether these cells might help limit congenital infection. We investigated this possibility by studying the activation status of M+B- cord blood monocytes and their ability to control T. cruzi in vitro infection. We showed that M+B- monocytes have an upregulated capacity to produce the inflammatory cytokine TNF-α and a better ability to control T. cruzi infection than M-B- monocytes. Our study also showed that T. cruzi-specific Abs transferred from the mother play a dual role by favoring trypomastigote entry into M+B- monocytes and inhibiting intracellular amastigote multiplication. These results support the possibility that some M+B- fetuses may eliminate the parasite transmitted in utero from their mothers, thus being uninfected at birth.

4.
Microbiol Spectr ; 11(1): e0347722, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36633426

RESUMO

Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) is a proteomic technique with proven efficiency in the identification of microorganisms, such as bacteria, fungi, and parasites. The present study aimed to evaluate the usefulness of MALDI-TOF MS for the characterization of Leishmania species circulating in Bolivia using hsp70 gene sequencing as a reference technique. 55 Leishmania strains that were isolated from patients with tegumentary leishmaniasis were analyzed. MALDI-TOF MS identified two species of the L. braziliensis complex (L. braziliensis, n = 26; L. braziliensis outlier, n = 18), one species of the L. guyanensis complex (L. guyanensis, n = 1), one species of the L. lainsoni complex (L. lainsoni, n = 2), and two species of the L. mexicana complex (L. amazonensis, n = 5; and L. garnhami, n = 3). All of the strains were correctly identified at the subgenus, genus, and complex level, but 10 of them (18%) were misidentified as other species within the same complex by the hsp70 gene sequencing, with 7 of these corresponding to possible hybrids. Thus, one L. braziliensis corresponded to L. peruviana, two L. braziliensis corresponded to L. braziliensis/L. peruviana possible hybrids, two L. amazonensis corresponded to L. mexicana, and three L. garnhami and two L. amazonensis corresponded to L. mexicana/L. amazonensis possible hybrids. Accordingly, MALDI-TOF MS could be used as an alternative to molecular techniques for the identification of Leishmania spp., as it is low cost, simple to apply, and able to quickly produce results. In Bolivia, its application would allow for the improvement of the management of patient follow-ups, the updating of the epidemiological data of the Leishmania species, and a contribution to the control of tegumentary leishmaniasis. IMPORTANCE The objective of the study was to evaluate the usefulness of MALDI-TOF MS for the characterization of Leishmania species circulating in Bolivia, in comparison with the sequencing of the hsp70 gene. In our study, all of the isolates could be identified, and no misidentifications were observed at the complex level. Although the equipment implies a high initial investment in our context, MALDI-TOF MS can be used in different areas of microbiology and significantly reduces the cost of testing. Once the parasite culture is obtained, the technique quickly yields information by accessing a free database that is available online. This would allow for the improvement of the management of patients and follow-ups, the updating of the epidemiological data of the species, and a contribution to the control of tegumentary leishmaniasis in Bolivia. Likewise, it can be used to determine a specific treatment to be given, according to the causal species of Leishmania, when there are protocols in this regard in the area.


Assuntos
Leishmania , Leishmaniose , Humanos , Bolívia/epidemiologia , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Lasers
5.
BMC Prim Care ; 23(1): 284, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36396996

RESUMO

BACKGROUND: Strongyloides stercoralis is widespread; however, there is limited information on its prevalence owing to laboratory underestimation and low clinical manifestations. The Baermann method and agar culture stand out among the parasitological techniques. Strongyloides stercoralis is present in Bolivia, but its prevalence in children remains unknown. The objective of this study was to estimate the applicability of simple parasitological techniques to increase the detection of this parasite in children living in the tropics. METHODS: This cross-sectional study was conducted in a tropical village in Cochabamba, Bolivia. Participants were 304 children aged 5 - 12 years who provided stool samples for different parasitological analyses (direct examination, Ritchie, Baermann, and Dancescu techniques), and their parents provided informed consent. RESULTS: Up to 64.8% of pathogenic parasites were detected using the modified Ritchie method. The Baermann technique identified 17.8% of Strongyloides stercoralis cases, and a high sensitivity with respect to the Baermann technique was only for the Dancescu technique (75.9%) that is also specific for Strongyloides stercoralis, followed by 66.7% for the modified Ritchie technique, which is used in second-line care. DISCUSSION: The Baermann technique is the best parasitological option for improving Strongyloides stercoralis diagnosis in the first-line care of the Primary Health Care System. A particular cycle of reinfection, combined with the environment and some other risk factors are related with persistence. Control is difficult without a proper diagnosis, and the Baermann technique is an approach to the solution. We conclude that with a high suspicion of the presence of Strongyloides stercoralis, the use of the Baermann technique is strongly recommended as support for direct examination in primary health care systems especially in tropical areas.


Assuntos
Strongyloides stercoralis , Estrongiloidíase , Criança , Animais , Humanos , Estrongiloidíase/diagnóstico , Bolívia/epidemiologia , Estudos Transversais , Fezes/parasitologia , Atenção à Saúde
6.
Acta Trop ; 235: 106632, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35932843

RESUMO

Chagas disease, caused by the Trypanosoma cruzi parasite in the Americas affects ∼ 7 million people, 30% with cardiac tissue damage and 10-15% with digestive disorders. In this study, we have developed a protocol to detect the presence of the parasite and estimate its load in resected dysfunctional tissue segments of chronically infected patients with digestive megacolon. We have included samples from 43 individuals, 38/5 with positive/negative serology for Chagas disease and digestive syndromes. Samples of 1.5 to 2.0 cm2 were taken from different points of the dysfunctional digestive tract in specialized centres in Cochabamba, Bolivia. T. cruzi cultures were performed by inoculation with NNN-LIT culture medium, and genomic material was obtained from the samples for multiplex qPCR with TaqMan probes targeting satellite nuclear DNA. Cultures failed to isolate T. cruzi but qPCR reached a sensitivity of 42.1% (16/38) with all three spots and in triplicate. A new quantification methodology using synthetic satellite DNA as quantitation standard revealed parasite loads ranging from 2.2 × 102 to 1.0 × 106 satellite DNA copies/µl. Positive samples from the distal end showed a higher parasite load. The results of the present study strengthen and add further evidence to previous findings in an experimental mouse model of chronic T. cruzi infection, providing a valuable tool to improve scientific knowledge on the relevance of the digestive tract in parasite persistence, and underline the need of a better understanding of host-pathogen interaction in digestive tissues, considering pathophysiology, disease immunology and response to treatment.


Assuntos
Doença de Chagas , Megacolo , Trypanosoma cruzi , Animais , Doença de Chagas/parasitologia , DNA Satélite , Humanos , Megacolo/genética , Camundongos , Carga Parasitária/métodos , Trypanosoma cruzi/genética
7.
Transbound Emerg Dis ; 69(4): 2242-2255, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34232559

RESUMO

Leishmaniasis is caused by protozoans of the Leishmania genus, which includes more than 20 species capable of infecting humans worldwide. In the Americas, the most widespread specie is L. braziliensis, present in 18 countries including Bolivia. The taxonomic position of the L. braziliensis complex has been a subject of controversy, complicated further by the recent identification of a particular subpopulation named L. braziliensis atypical or outlier. The aim of this study was to carry out a systematic analysis of the L. braziliensis complex in Bolivia and to describe the associated clinical characteristics. Forty-one strains were analyzed by sequencing an amplified 1245 bp fragment of the hsp70 gene, which allowed its identification as: 24 (59%) L. braziliensis, 16 (39%) L. braziliensis outlier, and one (2%) L. peruviana. In a dendrogram constructed, L. braziliensis and L. peruviana are grouped in the same cluster, whilst L. braziliensis outlier appears in a separate branch. Sequence alignment allowed the identification of five non-polymorphic nucleotide positions (288, 297, 642, 993, and 1213) that discriminate L. braziliensis and L. peruviana from L. braziliensis outlier. Moreover, nucleotide positions 51 and 561 enable L. peruviana to be discriminated from the other two taxa. A greater diversity was observed in L. braziliensis outlier than in L. braziliensis-L. peruviana. The 41 strains came from 32 patients with tegumentary leishmaniasis, among which 22 patients (69%) presented cutaneous lesions (11 caused by L. braziliensis and 11 by L. braziliensis outlier) and 10 patients (31%) mucocutaneous lesions (eight caused by L. braziliensis, one by L. braziliensis outlier, and one by L. peruviana). Nine patients (28%) simultaneously provided two isolates, each from a separate lesion, and in each case the same genotype was identified in both. Treatment failure was observed in six patients infected with L. braziliensis and one patient with L. peruviana.


Assuntos
Leishmania braziliensis , Leishmania , Leishmaniose Mucocutânea , Leishmaniose , Animais , Bolívia/epidemiologia , Humanos , Leishmania braziliensis/genética , Leishmaniose/veterinária , Leishmaniose Mucocutânea/veterinária , Nucleotídeos
8.
PLoS Negl Trop Dis ; 15(3): e0009223, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33667232

RESUMO

BACKGROUND: Tegumentary leishmaniasis (TL) is a parasitic disease that can present a cutaneous or mucocutaneous clinical form (CL and MCL, respectively). The disease is caused by different Leishmania species and transmitted by phlebotomine sand flies. Bolivia has one of the highest incidences of the disease in South America and the diagnosis is done by parasitological techniques. Our aim was to describe the clinical and immunological characteristics of CL and MCL patients attending the leishmaniasis reference center in Cochabamba, Bolivia, in order to gain updated clinical and epidemiological information, to evaluate the diagnostic methods used and to identify biomarkers related to clinical disease and its evolution. METHODOLOGY/PRINCIPAL FINDINGS: The study was conducted from September 2014 to November 2015 and 135 patients with lesions compatible with CL or MCL were included. Epidemiological and clinical data were collected using a semi-structured questionnaire. Two parasitological diagnostic methods were used: Giemsa-stained smears and culture of lesion aspirates. Blood samples obtained from participants were used to measure the concentrations of different cytokines. 59.2% (80/135) were leishmaniasis confirmed cases (CL: 71.3%; MCL: 28.7%). Sixty percent of the confirmed cases were positive by smears and 90.6% were positive by culture. 53.8% were primo-infections. Eotaxin and monokine induced by IFN-γ presented higher serum concentrations in the MCL clinical presentation compared to CL cases and no-cases. None of the cytokines presented different concentrations between primo-infections and secondary infections due to treatment failure. CONCLUSIONS/SIGNIFICANCE: In Bolivia, parasitological diagnosis remains the reference standard in diagnosis of leishmaniasis because of its high specificity, whereas the sensitivity varies over a wide range leading to loss of cases. Until more accurate tools are implemented, all patients should be tested by both smears and culture of lesion aspirates to minimize the risk of false negatives. Our results showed higher concentrations of several cytokines in MCL compared to CL, but no differences were observed between CL and no-cases. In addition, none of the cytokines differed between primary and secondary infections. These results highlight the need of further research to identify biomarkers of susceptibility and disease progression, in addition to looking at the local cellular immune responses in the lesions.


Assuntos
Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/patologia , Adolescente , Adulto , Biomarcadores/sangue , Bolívia/epidemiologia , Criança , Citocinas/genética , Citocinas/metabolismo , Feminino , Regulação da Expressão Gênica/imunologia , Humanos , Imunoensaio/métodos , Leishmaniose Cutânea/epidemiologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Am J Trop Med Hyg ; 75(6): 1082-4, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17172370

RESUMO

Although Trypanosoma cruzi can be transmitted transplacentally and induce congenital infection, no data are available about the presence of this parasite in human amniotic fluid. We examined 8, 19, and 4 amniotic fluid samples (collected at delivery or by aspiration of gastric content of neonates) from control uninfected mothers (M-B-), infected mothers delivering uninfected newborns (M+B-), and mothers of confirmed congenital cases (M+B+), respectively. Polymerase chain reaction (PCR), using nuclear and kinetoplastic DNA primers (Tcz1-Tcz2 and 121-122), were negative for all control M-B- samples, but positive for 5 of 19 M+B- and 2 of 4 M+B+ samples. To determine the number of parasites in the positive samples, real-time PCR using S35/S36 kinetoplastic DNA was performed. Only one M+B+ sample presented a high parasitic DNA amount, whereas the other six PCR-positive samples displayed traces of T. cruzi DNA. In conclusion, the release of parasites in amniotic fluid is probably a rare event that cannot be helpful for the routine diagnosis of congenital Chagas disease.


Assuntos
Líquido Amniótico/parasitologia , Doença de Chagas/diagnóstico , Diagnóstico Pré-Natal , Trypanosoma cruzi/isolamento & purificação , Animais , Primers do DNA , Feminino , Humanos , Recém-Nascido , Gravidez , Reprodutibilidade dos Testes
10.
Rev Soc Bras Med Trop ; 38 Suppl 2: 73-6, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-16482820

RESUMO

In the endemic regions of Bolivia the infection of the feminine population in fertile age by T. cruzi is frequent (20 to 50 % of the women in fertile age) and the rate of fetal maternal transmission is of approximately 5%. A great percentage of infected women do not transmit the infection to the fetus. The intention of the present study carried out at the Maternal-Infantile Hospital Germán Urquidi of Cochabamba (Bolivia) is to contribute to the knowledge regarding the pregnancy and birth of a newborn of Chagas infected women who do not transmit the infection to the fetus. 2124 mothers and 2,155 newborns were studied. The prevalence of infection by T. cruzi among these pregnant women is of 26,3%. Two groups of mothers were studied: 554 that presented infection by T. cruzi (group M+B-) and 1520 not infected (group control M-B-). Both groups of mothers are comparable in their anthropometric and obstetrical antecedents. The mothers (M+B+) are in average older than those not infected (p<0.05), which will probably have an influence on the number of gestations and abortion antecedents, which were of p<0.05 and p=0.01 respectively. Among the different anthropometric and biological parameters studied in newborns of groups M+B- and M-B -, no statistically significant differences between both groups were found. It can be inferred that the chronic maternal infection by T. cruzi seems to have no clinical influence, neither on the course of the pregnancy nor during birth, if a group of T. cruzi infected mothers is compared to a non infected group.


Assuntos
Doença de Chagas/epidemiologia , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Complicações Parasitárias na Gravidez/epidemiologia , Resultado da Gravidez , Adulto , Antropometria , Índice de Apgar , Bolívia/epidemiologia , Estudos de Casos e Controles , Doença de Chagas/diagnóstico , Doença de Chagas/transmissão , Feminino , Humanos , Recém-Nascido , Gravidez , Prevalência
11.
Rev Soc Bras Med Trop ; 38 Suppl 2: 101-4, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-16482826

RESUMO

The mechanisms of congenital transmission of Chagas disease remain largely unknown. To better understand the role of maternal immunology during pregnancy in congenital Chagas transmission, we studied the cytokine production and the parasitic load in three groups of mothers: infected mothers who transmitted the disease to their babies (M+B+-), infected mothers who did not transmit the disease to their babies (M+B-) and not infected mothers as a control group (M-B-). M+B+ mothers produced less IFNgamma and more IL-10 than the M+B- mothers, and they are not able to produce IL-2. M+B+ mothers showed a higher parasitic load. These results, indicated that the congenital Chagas transmission is associated with an immunological imbalance and a high parasitic load in the M+B+ mothers.


Assuntos
Doença de Chagas/imunologia , Doença de Chagas/transmissão , Citocinas/biossíntese , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez/imunologia , Trypanosoma cruzi/fisiologia , Animais , Portador Sadio/imunologia , Doença de Chagas/parasitologia , Citocinas/imunologia , Feminino , Humanos , Imunidade Celular , Interferon gama/biossíntese , Interferons/biossíntese , Gravidez
12.
Rev Soc Bras Med Trop ; 38 Suppl 2: 17-20, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-16482806

RESUMO

In Bolivia, the prevalence of infection by T. cruzi in women in fertile age can vary between 20 and 60%. The present study made in the Maternity Germin Urquidi of Cochabamba - Bolivia, it has demonstrated, that 19.9% of the mothers who go to this hospitable center to be taken care of in the childbirth, they are carrying of the infection and that 4,6% of them, they are going to transmit, by transplacentaria route, the infection to its babies. Of the 71 children born with congenital Chagas, only 47,8 % present/display some type of alteration or of development(Apgar to 1 minute low, BPN, prematuridad, pathological dismadurez) or signs (SDR, hepatomegalia, esplenomegalia, neurological signs, cardiomegalia, anasarca, petequias). When investigating the effect of the differences in the vectorial density (low, medium and high) of the zone of maternal residence, on the transmission of the infection of the mother infected to the fetus, we concluded that the rate of transmission of the congenital infection of T. cruzi is not modified by the level of endemicidad of the zone of maternal residence. By another infected new born sides whose mothers reside in zones of high endemicidad present/display, most frequently and of significant way, Apgar to 1 minute < to 7, low weight when being born and prematuridad or an association of these alterations with respiratory syndrome of distress or anasarca, when one compares them with new born of resident mothers in the zones of loss or medium endemicidad, mortality in this group is greater. These results suggest calls to account it of the mothers, in areas of high endemicidad, she is associate with a serious increase in the risk of Disease of newborn severe and mortal congenital Chagas in.


Assuntos
Doença de Chagas/congênito , Doenças Endêmicas , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Insetos Vetores/fisiologia , Complicações Parasitárias na Gravidez , Adulto , Animais , Índice de Apgar , Bolívia/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/transmissão , Demografia , Fatores Epidemiológicos , Feminino , Humanos , Recém-Nascido , Masculino , Densidade Demográfica , Gravidez , Prevalência , Trypanosoma cruzi/fisiologia
13.
Rev Soc Bras Med Trop ; 38 Suppl 2: 58-61, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-16482816

RESUMO

The aim of this study was to validate the method of microhematocrit tube, as a rapid method to estimate the parasitemia in blood and to associate the parasites concentration with the morbidity and mortality of new born children with congenital Chagas diseases. Our results were determined experimentally and shown that the detection limit of the microhematocrit tube method is 40 parasites/ml when at least one of the four observed tubes is positive. Besides, it was also established that when the four examined tubes are positive the parasitemia in blood reaches more than 100 parasites/ml. It is important to highlight the modification made by our laboratory in the microscopic observation of the microhematocrit tubes with respect to the methodology used by previous investigators. A positive association exists between a high number of parasites in blood and the morbi-mortality of the newly born children with congenital chagas. The results of positive association between the parasitic load and the morbility and mortality could constitute an argument to understand the possible role of the parasite in the pathology of the disease.


Assuntos
Doença de Chagas/congênito , Doença de Chagas/parasitologia , Contagem de Ovos de Parasitas/métodos , Parasitemia , Trypanosoma cruzi/isolamento & purificação , Animais , Peso ao Nascer , Bolívia/epidemiologia , Doença de Chagas/diagnóstico , Feminino , Hematócrito/instrumentação , Hematócrito/métodos , Humanos , Recém-Nascido , Masculino , Camundongos , Parasitemia/mortalidade , Sensibilidade e Especificidade , Cordão Umbilical
14.
Am J Trop Med Hyg ; 70(2): 201-9, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14993634

RESUMO

This work compares the results of two epidemiologic and clinical surveys on the consequences of maternal chronic Trypanosoma cruzi infection. They were conducted in 1992-1994 and 1999-2001 in the same maternity clinic in Bolivia, a country highly endemic for infection with this parasite. In both surveys, the materno-fetal transmission of parasites occurred in 5-6% of the infected mothers. Maternal chronic T. cruzi infection had no effect on pregnancy outcome and health of newborns when there was no materno-fetal transmission of parasites. Comparisons between the older and the more recent surveys highlighted significant reductions in frequencies of symptomatic cases (from 54% to 45%), Apgar scores < 7, and low birth weights and prematurity (from 32-50% to 6-16%) among congenitally infected babies. Neonatal mortality related to congenital Chagas disease also decreased from 13% to 2% in the interval between both studies. These results suggest that the decrease in poverty that has occurred in Bolivia between both surveys might have contributed to reduce the morbidity and mortality, but not the transmission rate of T. cruzi congenital infection, which remains a serious public health problem in this country.


Assuntos
Doença de Chagas/congênito , Doença de Chagas/epidemiologia , Transmissão Vertical de Doenças Infecciosas , Complicações Parasitárias na Gravidez/epidemiologia , Resultado da Gravidez , Adulto , Fatores Etários , Índice de Apgar , Bolívia/epidemiologia , Doença de Chagas/mortalidade , Doença de Chagas/transmissão , Estudos de Coortes , Feminino , Humanos , Incidência , Mortalidade Infantil , Recém-Nascido , Masculino , Morbidade , Paridade , Gravidez , Resultado da Gravidez/epidemiologia , Prevalência , Fatores Sexuais
15.
Food Nutr Res ; 58: 23353, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25397995

RESUMO

BACKGROUND: The role of micronutrient status for the incidence and clinical course of cutaneous leishmaniasis is not much studied. Still zinc supplementation in leishmaniasis has shown some effect on the clinical recovery, but the evidence in humans is limited. OBJECTIVE: To compare biochemical nutritional status in cutaneous leishmaniasis patients with that in controls and to study the effects of zinc supplementation for 60 days. DESIGN: Twenty-nine patients with cutaneous leishmaniasis were treated with antimony for 20 days. Fourteen of them got 45 mg zinc daily and 15 of them got placebo. Biomarkers of nutritional and inflammatory status and changes in size and characteristics of skin lesions were measured. RESULTS: The level of transferrin receptor was higher in patients than in controls but otherwise no differences in nutritional status were found between patients and controls. No significant effects of zinc supplementation on the clinical recovery were observed as assessed by lesion area reduction and characteristics or on biochemical parameters. CONCLUSIONS: It is concluded that nutritional status was essentially unaffected in cutaneous leishmaniasis and that oral zinc supplementation administered together with intramuscular injection of antimony had no additional clinical benefit.

17.
PLoS One ; 7(5): e36578, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22590570

RESUMO

The aim of this study was to establish the phylogenetic relationships of trypanosomes present in blood samples of Bolivian Carollia bats. Eighteen cloned stocks were isolated from 115 bats belonging to Carollia perspicillata (Phyllostomidae) from three Amazonian areas of the Chapare Province of Bolivia and studied by xenodiagnosis using the vectors Rhodnius robustus and Triatoma infestans (Trypanosoma cruzi marenkellei) or haemoculture (Trypanosoma dionisii). The PCR DNA amplified was analyzed by nucleotide sequences of maxicircles encoding cytochrome b and by means of the molecular size of hyper variable regions of minicircles. Ten samples were classified as Trypanosoma cruzi marinkellei and 8 samples as Trypanosoma dionisii. The two species have a different molecular size profile with respect to the amplified regions of minicircles and also with respect to Trypanosoma cruzi and Trypanosoma rangeli used for comparative purpose. We conclude the presence of two species of bat trypanosomes in these samples, which can clearly be identified by the methods used in this study. The presence of these trypanosomes in Amazonian bats is discussed.


Assuntos
Quirópteros/parasitologia , Citocromos b/genética , Filogenia , Proteínas de Protozoários/genética , Trypanosoma/genética , Animais , Bolívia , Análise de Sequência de DNA
18.
Vet Parasitol ; 177(1-2): 171-4, 2011 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-21146310

RESUMO

Data on Leishmania spp. infection in dogs in Bolivia is scarce. Dogs from an area where 90% of human cutaneous leishmaniasis (CL) cases are due to Leishmania (Viannia) braziliensis were screened for Leishmania infection using established enzyme-linked immunosorbent antibody test (ELISA) protocols. Although none of the 51 dogs surveyed had clinical lesions indicative of CL, 6 out of 51 (11.8%) sampled dogs tested positive by ELISA.


Assuntos
Doenças do Cão/parasitologia , Leishmaniose/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Bolívia/epidemiologia , Doenças do Cão/epidemiologia , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Leishmaniose/sangue , Leishmaniose/epidemiologia , Masculino , Prevalência
19.
Am J Trop Med Hyg ; 81(4): 555-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19815865

RESUMO

We describe the first case of Leishmania/HIV co-infection reported in Bolivia. Initially hospitalized with a diagnosis of pneumonia and bronchitis, the patient had numerous cutaneous and mucosal lesions caused by Leishmania (Viannia) braziliensis. The patient was also diagnosed as severely immunocompromised because of HIV infection.


Assuntos
Infecções por HIV/complicações , Leishmania braziliensis , Leishmaniose Mucocutânea/complicações , Leishmaniose Mucocutânea/patologia , Adulto , Animais , Anti-Infecciosos/uso terapêutico , Bolívia/epidemiologia , Infecções por HIV/epidemiologia , Humanos , Leishmaniose Mucocutânea/epidemiologia , Masculino
20.
Gac. méd. boliv ; 36(1): 15-20, jun. 2013. ilus
Artigo em Espanhol | LILACS | ID: lil-737890

RESUMO

Objetivos: se realiza un estudio del estatus inmunológico, cuantificando el perfil de citoquinas Thl (INF-y) y Th2 (IL-13) y células T CD3+, CD4+ y CD8+ como variables que puedan brindar información sobre el vinculo y/o asociación a la falla terapéutica. Métodos: se cuantifi-co los niveles de INF-y , IL-13, CD4 + y CD8+ en tres grupos de estudio: a) Pacientes con LT y falla terapéutica (RESISTENTES), b) Pacientes tratados que respondieron al tratamiento de forma exitosa (SENSIBLES) c) Pacientes sanos (GRUPO CONTROL). Resultados: los resultados indican, que la respuesta específica inmune de los pacientes Resistentes y Sensibles esta polarizada hacia la respuesta TH1 y los valores de los Linfocitos T CD4+ y CD8+ estaban por debajo de los valores normales en los tres grupos de estudio. Los niveles de producción de INF- y fue mayor que la IL-13, siendo mas pronunciada en pacientes Resistentes que Sensibles en respuesta al Ag de Leishmania, la tipificación de las cepas que fueron aisladas de los pacientes resistentes, identificaron a: Leishmania brasiliensis y Leishmania guayanensis. Conclusiones: en relación a la falla terapéutica de los pacientes resistentes, estarían también involucrados los factores relacionados al parásito y otros factores extrínsecos al huésped.


Objectives: is a study of the immune status, quantifying the Th1 cytokine profile (IFN-y) and Th2 (IL-13) and CD3 + T cells, CD4 + and CD8 + as variables that can provide information on the link and / or association therapeutic failure. Methods: we quantified the levels of INF-y, IL-13, CD4 + and CD8 + in three study groups: a) patients with LT and therapeutic failure (RESISTANT), b) Treated patients who responded to treatment successfully (SENSITIVE ) c) healthy patients (CONTROL GROUP). Results: the results indicate that the specific immune response of resistant and sensitive patients is polarized toward the TH1 response and values of CD4 + T lymphocytes and CD8 + were below normal values in the three groups. The levels of IFN-y production was higher than IL-13, being more pronounced in patients resistant to sensitive in response to Leishmania Ag, the typing of the strains that were isolated from patients resistant identified: Leishmania brasiliensis and guayanensis Leishmania. Conclusions: regarding treatment failure resistant patients, would also be involved factors related to the parasite and other extrinsic factors to the host.


Assuntos
Leishmaniose Cutânea
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