Abstract Background: Cryptosporidium spp. are pathogenic protozoans that play an important role in developing diseases in the elderly, children, and immunosuppressed individuals. Methods: The objective of this study was to detect and genetically characterize Cryptosporidium spp. in kidney transplanted patients (n = 97 samples; group 1) and immunosuppressed individuals from an outpatient clinic suspected of having Cryptosporidium infection (n = 53 samples; group 2). All fecal samples were analyzed by parasitological stool examination, immunochromatographic test, and real-time polymerase chain reaction (real-time PCR). Cryptosporidium-positive samples were tested using nested PCR for the gp60 gene, followed by sequencing for subtype determination. Results: Parasitological examination was negative in all Group 1, and positive in four Group 2 samples. Real-time PCR revealed Cryptosporidium in 13 samples: four in Group 1 (three C. hominis and one C. parvum) and nine in Group 2 (seven C. hominis, one C. parvum, and one mixed C. hominis/C. parvum). The immunochromatographic test was reactive in 11 samples (four in Group 1 and seven in Group 2). All 11 C. hominis isolates were identified as subtype IbA10G2 and one C. parvum as subtype IIbA15G2R1. All C. hominis belonged to subtype IbA10G2, which is recognized as the most prevalent and pathogenic subtype. Conclusions: This study showed, for the first time, that the presence of Cryptosporidium subtypes is considered more virulent in Brazilian transplanted kidney patients.

ABSTRACT Cryptosporidiosis is a disease caused by the Cryptosporidium spp parasite. As some species of Cryptosporidium have a wide host spectrum, the characterization of the pathogen at the species or genotype level is of great importance to define the sources of infection for humans and the potential for public health. This study investigated the diversity of the genus Cryptosporidium spp. in humans from all over the American continent and observed whether the method used to search for the parasite influenced the prevalence found in the Americas. This systematic review was carried out using the Pubmed, Science direct, Lilacs, Scielo, and Scopus databases with publications from January 1, 2010, to December 31, 2020. For data synthesis, the PRISMA flowchart was used and for the meta-analysis we used the MetaXL program. Of the selected publications, 57, 9 and 16 belonged to the region of South, Central and North America, respectively. The prevalence found for South, Central, and North America was 7%, 7%, and 8%, respectively, when analyzing publications that used only the microscopy method. When we analyzed the publications that used immunological and molecular methods, we found prevalences of 10%, 9%, and 21% for South, Central, and North America, respectively. The C. hominis subtype IbA10G2 was the most reported in the American continent, followed by subtype IeA11G3T3 and, for C. parvum, subtype IIaA15G2RI was the most reported. In conclusion, Cryptosporidium spp. is present throughout the American continent and its prevalence is higher when immunological and/or molecular methods are used, in addition to direct microscopic examination.

ABSTRACT Cryptosporidium spp. is a pathogenic protozoan present in the gastrointestinal tract of several hosts. This protozoan was originally classified as within the Coccidia Class and has recently been reclassified to gregarine based on studies that observed the evolutionary phases from the process of excision and sequencing of the 18S rRNA gene. Molecular biology techniques have become diagnostic tools and have also been used to understand the epidemiology of Cryptosporidium spp., since several species of this genus are very similar morphologically and morphometrically. Molecular techniques have been used in the identification of parasites, at the species and subtypes levels and to study disease transmission. The laboratory diagnosis of human cryptosporidiosis can be made by parasite detection methods, such as optical microscopy, antigens or genetic material detection, as well as serum antibodies raised to Cryptosporidium spp. Molecular methods were developed and allowed, not only an extensive revision of the taxonomy, but also an improvement in the laboratory diagnosis. In Brazil, there are few reports of Cryptosporidium spp. outbreaks in humans and all of them took place in nurseries. A few epidemiological studies developed in Brazil have used molecular methods for the detection of Cryptosporidium spp., as well as genotyping studies of their species and subtypes. The use of real-time PCR, together with microscopy and immunochromatography techniques, would result in a more precise diagnosis of cryptosporidiosis. The analysis of genotypes, subtypes and clonality of Cryptosporidium could be useful to understand and define the prognosis and severity of infections.

The identification and characterisation of Cryptosporidiumgenotypes and subtypes are fundamental to the study of cryptosporidiosis epidemiology, aiding in prevention and control strategies. The objective was to determine the genetic diversity ofCryptosporidium in samples obtained from hospitals of Rio de Janeiro, Brazil, and Buenos Aires, Argentina. Samples were analysed by microscopy and TaqMan polymerase chain reaction (PCR) assays forCryptosporidium detection, genotyped by nested-PCR-restriction fragment length polymorphism (RFLP) analysis of the 18S rRNA gene and subtyped by DNA sequencing of the gp60 gene. Among the 89 samples from Rio de Janeiro, Cryptosporidium spp were detected in 26 by microscopy/TaqMan PCR. In samples from Buenos Aires,Cryptosporidium was diagnosed in 15 patients of the 132 studied. The TaqMan PCR and the nested-PCR-RFLP detected Cryptosporidium parvum, Cryptosporidium hominis, and co-infections of both species. In Brazilian samples, the subtypes IbA10G2 and IIcA5G3 were observed. The subtypes found in Argentinean samples were IbA10G2, IaA10G1R4, IaA11G1R4, and IeA11G3T3, and mixed subtypes of Ia and IIa families were detected in the co-infections. C. hominis was the species more frequently detected, and subtype family Ib was reported in both countries. Subtype diversity was higher in Buenos Aires than in Rio de Janeiro and two new subtypes were described for the first time.

Introduction: This study evaluated the frequency of intestinal parasites, emphasizing the identification and differentiation of Entamoeba spp. Methods: Multiplex polymerase chain reaction (PCR), coproantigen tests and morphometric analysis were performed for Entamoeba spp. differentiation. Results: The overall frequency of intestinal parasites was 65%. Entamoeba histolytica was detected by the coproantigen test, and the PCR showed that Entamoeba dispar predominated in the population. In contrast, morphometric analysis was important for identifying Entamoeba hartmanni. Conclusions: It is possible to identify the causative agent of amoebiasis and to differentiate this agent from other species by combining techniques.

The aim of this study was to evaluate the efficacy of a polymerase chain reaction (PCR)-based method to detect Schistosoma mansoni DNA in stool samples from individuals living in a low-endemicity area in Brazil. Of the 125 initial stool samples, 80 were ELISA reactive and eggs were identified in 19 of the samples by parasitological examination. For the PCR evaluations, 56 stool samples were selected and divided into five groups. Groups I-IV were scored negative for S. mansoni eggs by parasitological examination. Groups I and II were ELISA reactive, whereas Groups III and IV were ELISA nonreactive. Groups II and III were positive for other intestinal parasites. PCR testing scored eight samples as positive from these four groups. Group V represented the S. mansoni -positive group and it included ELISA-reactive samples that were scored positive for S. mansoni by one or more parasitological examinations (6/19 were positive by Kato-Katz method, 9/17 by saline gradient and 10/13 by Helmintex®). PCR scored 13 of these 19 samples as positive for S. mansoni . We conclude that while none of these methods yielded 100% sensitivity, a combination of techniques should be effective for improving the detection of S. mansoni infection in low-endemicity areas.

This study reports the first genetic characterisation of Cryptosporidium isolates in Brazil using real-time polymerase chain reaction (RT-PCR). A total of 1,197 faecal specimens from children and 10 specimens from human immunodeficiency virus-infected patients were collected between 1999-2010 and screened using microscopy. Forty-eight Cryptosporidium oocyst-positive isolates were identified and analysed using a generic TaqMan assay targeting the 18S rRNA to detect Cryptosporidium species and two other TaqMan assays to identify Cryptosporidium hominis and Cryptosporidium parvum. The 18S rRNA assay detected Cryptosporidium species in all 48 of the stool specimens. The C. parvum TaqMan assay correctly identified five/48 stool samples, while 37/48 stool specimens were correctly amplified in the C. hominis TaqMan assay. The results obtained in this study support previous findings showing that C. hominis infections are more prevalent than C. parvum infections in Brazil and they demonstrate that the TaqMan RT-PCR procedure is a simple, fast and valuable tool for the detection and differentiation of Cryptosporidium species.

Amebiasis is an infection caused by Entamoeba histolytica. However, differentiation between E. histolytica and Entamoeba dispar, which are morphologically identical species, is essential for treatment decision, precaution of the invasive disease and public health. The purpose of the present study was to evaluate a Multiplex -PCR for detection and differentiation of E. histolytica from E. dispar from fresh stool samples in comparison with the coproantigen commercial ELISA. Microscopic examination of stools using the Coprotest method, detection of stool antigen by enzyme-linked immunosorbent assay kit and a home made Multiplex-PCR, were used for the diagnosis of amoebiasis infection. Analysis of the 127 stools samples by microscopy examination demonstrated that only 27 (21%) samples were positive for E. histolytica/E. dispar complex. Among these stool samples, 11 were positive by Multiplex-PCR, with nine presenting the diagnostic fragment characteristic of E. dispar (96 bp) and two presenting diagnostic fragment of E. histolytica (132 bp). Among negative samples detected by microscopic examination, three positive samples for E. dispar and one positive for E. histolytica by Multiplex-PCR was observed. This denotes a low sensibility of microscopic examination when a single stool sample is analyzed. Assay for detection of E. histolytica antigen was concordant with multiplex-PCR in relation to E. histolytica. Statistical analysis comparing the sensibility tests was not done because of the low number of E. histolytica cases. The results demonstrate the importance of the specific techniques use for the differentiation between E. histolytica and E. dispar.

O processo de formação da placa aterosclerótica inicia-se na infância e progride lentamente até a vida adulta, quando ocorrerão as manifestações clínicas da doença. O objetivo deste trabalho foi realizar um estudo da concentração plasmática de colesterol total (CT), colesterol da lipoproteína de baixa densidade (LDL-C), triglicéride (TG) e colesterol da lipoproteína de alta densidade (HDL-C) numa população na faixa etária de 2 a 19 anos, de ambos os sexos, atendida no ambulatório do Hospital Universitário Antônio Pedro (HUAP). Os dados dos prontuários foram obtidos entre dezembro/2004 e janeiro/2006 e as concentrações plasmáticas foram correlacionadas com os fatores de risco para dislipidemia. As dosagens foram feitas no Laboratório de Bioquímica Clínica do HUAP. Os níveis plasmáticos do CT, LDL-C, TG e HDL-c foram maiores no sexo feminino do que no masculino e este fato é compatível com a literatura. A média dos valores de TG, CT, LDL-C e HDL-C observada na população estudada mostrou-se elevada para esses parâmetros, principalmente em pacientes que apresentam doenças, como síndrome nefrótica, lúpus eritematoso sistêmico (LES) e diabetes mellitus (DM). Este trabalho reforça a tese da necessidade de utilização, no Brasil, de estudos sobre os intervalos de valores de referência do perfil lipídico nesta faixa etária e também sobre o perfil dos níveis desses lípides na população considerada sadia.

Atherosclerotic plaques form early in childhood and progress slowly until adult life, when clinical manifestations show. The goal of this study was to analyze the concentrations in plasma of total cholesterol, LDL-cholesterol (LDL-C), triglycerides (TG) and HDL-cholesterol (HDL-C) in a group of children of both sexes and up to 19 years of age, who are attending at the University Hospital Antônio Pedro (HUAP). Patient admission sheets between December 2004 and January 2006 were analyzed for dyslipidemic risk factors, and correlated with the respective lipid plasma concentrations, determined at the Laboratory of Clinical Chemistry (HUAP). The plasma levels of total cholesterol, LDL-C, TG and HDL-C in female patients were higher than in male patients, suggesting the influence of sexual maturation as described in the literature. The mean concentrations of total cholesterol, LDL-C, TG and HDL-C were elevated in the investigated group, mainly in patients presenting with other pathologies, such as nephrotic syndromes, diabetes mellitus and systemic lupus erythematosus. Our results suggest that, in Brazil, the reference value interval of lipoprotein levels should be investigated more thoroughly in this age group, as well as in children who are considered healthy.

Integrando as pesquisas sobre parasitoses na região do entorno do Parque Nacional Serra da Capivara, Piauí, Brasil, realizadas entre 1999 e 2001, o presente estudo tem como objetivo avaliar a situação epidemiológica da cisticercose humana no Município de João Costa, no Nordeste do Brasil. Foram obtidas informações clínico-epidemiológicas e coletadas amostras de sangue para testes sorológicos imunoenzimáticos (ELISA e Western blot), empregando cisticercos de Taenia crassiceps como antígeno. Na primeira etapa, em 1999, foram investigadas 169 pessoas com história confirmada ou suspeita de infecção/doença pelo complexo teníase-cisticercose, e seus familiares. Na análise, 13,6% das pessoas apresentaram soros reagentes para cisticercose pelo método ELISA. Na segunda etapa, em 2001, foram avaliadas 92 amostras de soro de indivíduos reativos para cisticercose detectados no primeiro momento e seus familiares, sendo que 24,0% das amostras de soro foram reagentes para cisticercose pelo ELISA, e 29,0%, pelo WB. Nessa mesma etapa, realizou-se inquérito coprológico em 701 pessoas, incluindo voluntários. A prevalência de parasitoses intestinais foi de 51,0%, tendo sido observada uma maior prevalência de protozoários (95,0%) em relação aos helmintos (5,0%). Os resultados do estudo indicam o caráter endêmico da cisticercose na área, além da elevada freqüência de protozooses intestinais.

As part of parasitological studies in the area surrounding the Serra da Capivara National Park, Piauí State, Northeast Brazil, from 1999 to 2001, the current study aimed to evaluate the epidemiological profile of human cysticercosis in the Municipality of João Costa. Clinical and epidemiological data were obtained, and blood samples were drawn for immunoenzymatic serological tests (ELISA and Western blot), using Taenia crassiceps as the antigen. The first stage, in 1999, investigated 169 individuals with a confirmed history or suspicion of infection/disease involving the teniasis/cysticercosis complex, along with the family members. Some 13.6% of the individuals were seroreactive for cysticercosis by the ELISA method. The second stage, in 2001, evaluated 92 serum samples of individuals who had been detected as reactive for cysticercosis in the first stage, along with their family members; 24% of the samples were reactive to cysticercosis by ELISA and 29% by Western blot. During this same stage a coprological survey was performed with 701 individuals, including volunteers. Prevalence of intestinal parasites was 51%, with a higher prevalence of protozoans (95%) than helminths (5%). The results indicate the endemicity of cysticercosis in the area, in addition to the high frequency of intestinal protozoan infections.

Integrando as pesquisas sobre parasitoses na região do entorno do Parque Nacional Serra da Capivara, Piauí, Brasil, realizadas entre 1999 e 2001, o presente estudo tem como objetivo avaliar a situação epidemiológica da cisticercose humana no Município de João Costa, no Nordeste do Brasil. Foram obtidas informações clínico-epidemiológicas e coletadas amostras de sangue para testes sorológicos imunoenzimáticos (ELISA e Western blot), empregando cisticercos de Taenia crassiceps como antígeno. Na primeira etapa, em 1999, foram investigadas 169 pessoas com história confirmada ou suspeita de infecção/doença pelo complexo teníase-cisticercose, e seus familiares. Na análise, 13,6% das pessoas apresentaram soros reagentes para cisticercose pelo método ELISA. Na segunda etapa, em 2001, foram avaliadas 92 amostras de soro de indivíduos reativos para cisticercose detectados no primeiro momento e seus familiares, sendo que 24,0% das amostras de soro foram reagentes para cisticercose pelo ELISA, e 29,0%, pelo WB. Nessa mesma etapa, realizou-se inquérito coprológico em 701 pessoas, incluindo voluntários. A prevalência de parasitoses intestinais foi de 51,0%, tendo sido observada uma maior prevalência de protozoários (95,0%) em relação aos helmintos (5,0%). Os resultados do estudo indicam o caráter endêmico da cisticercose na área, além da elevada freqüência de protozooses intestinais.

As part of parasitological studies in the area surrounding the Serra da Capivara National Park, Piauí State, Northeast Brazil, from 1999 to 2001, the current study aimed to evaluate the epidemiological profile of human cysticercosis in the Municipality of João Costa. Clinical and epidemiological data were obtained, and blood samples were drawn for immunoenzymatic serological tests (ELISA and Western blot), using Taenia crassiceps as the antigen. The first stage, in 1999, investigated 169 individuals with a confirmed history or suspicion of infection/disease involving the teniasis/cysticercosis complex, along with the family members. Some 13.6% of the individuals were seroreactive for cysticercosis by the ELISA method. The second stage, in 2001, evaluated 92 serum samples of individuals who had been detected as reactive for cysticercosis in the first stage, along with their family members; 24% of the samples were reactive to cysticercosis by ELISA and 29% by Western blot. During this same stage a coprological survey was performed with 701 individuals, including volunteers. Prevalence of intestinal parasites was 51%, with a higher prevalence of protozoans (95%) than helminths (5%). The results indicate the endemicity of cysticercosis in the area, in addition to the high frequency of intestinal protozoan infections.

Introdução: O diagnóstico da neurocisticercose (NCC) deve ser feito pela associação de técnicas de imagem com métodos imunológicos sensíveis e específicos. Objetivos: Avaliar os métodos Elisa e Western blot (Wb), utilizando-se como antígeno extrato bruto salino da larva da Taenia solium, o Cysticercus cellulosae e Wb, empregando-se como antígeno cisticercos da Taenia crassiceps em amostras de soro, para o diagnóstico da NCC. Materiais e métodos: Foram avaliadas amostras de soro de 43 pacientes com diagnóstico de NCC: 21 por clínica, tomografia computadorizada de crânio (TC) e presença de anticorpos anticisticerco no líquido cefalorraquiano (LCR); 22 por clínica e TC e 229 pacientes com diferentes parasitoses. Para as análises desses materiais biológicos foram empregados os métodos Elisa, usando-se como antígeno C. cellulosae, e Wb, usando-se como antígeno C. cellulosae e Cysticercus longicollis. Resultados: O método Elisa utilizando C. cellulosae como antígeno apresentou especificidade de 95% e sensibilidade de 71%. O método Wb utilizando C. cellulosae ou C. longicollis como antígeno apresentou sensibilidade de 86% e especificidade de 99%. Conclusões: Os métodos imunológicos no LCR são importantes para a definição da NCC. Entretanto o método Elisa no soro ainda não é adequado pela sua baixa sensibilidade, mas o Wb apresentou alta especificidade e boa sensibilidade, podendo auxiliar no diagnóstico da NCC, possibilitando sugerir a existência de forma transicional da doença, não demonstrada pela TC.

Background: The diagnosis of neurocysticercosis (NCC) has been made by association of neuroimaging studies and use of sensitive and specific serological assays. Objectives: Evaluating Elisa and Western blot (Wb) tests using a crude extract of Cysticercus cellulosae (Taenia solium) as antigen and a Wb test using a glycoprotein of Cysticercus longicollis (Taenia crassiceps) as antigen for the diagnosis of NCC. Methods: Serum samples from 43 patients with NCC: 21patients presenting clinical manifestations, cerebral computed tomography findings compatible with cerebral lesions and high levels of anti-cysticercus antibodies in cerebrospinal fluid (CSF); 22 patients with clinical manifestations and cerebral computed tomography findings compatible with cerebral lesions and serum samples from 229 patients with other parasitic infections were tested by Elisa standardized with crude extract of C. cellulosae and Wb standardized with glicoprotein of C. cellulosae and C. longicollis. Results: The Elisa test using crude extract of C. cellulosae showed specificity of 95% and sensibility of 71%. Both tests using glycoproteins of either C. cellulosae or C. longicollis showed specificity of 99% and sensibility of 86%. Conclusions: The use of immunological techniques for antibodies detection in CSF was shown to be an important tool for NCC diagnosis. However, detection of antibodies in serum lacked sensibility when Elisa was evaluated. The Wb assay in serum samples was sensitive and specific and it can be helpful for the diagnosis of the transitional form of NCC frequently not detected by cerebral computed tomography.