Food handlers: an important reservoir of protozoans and helminth parasites of public health importance / Manipuladores de alimentos: um importante reservatório de protozoários e helmintos parasitas de importância para a saúde pública

Food handlers plays a primary role in the transmission of pathogenically important protozoans and helminth parasites. This study was aimed to evaluate the prevalence of intestinal pathogenic protozoans and helminth parasites among food handlers in and around University of Malakand, Lower Dir, Pakistan. Stool samples were collected from 642 food handlers (all of male) in a cross-sectional study from January to November, 2017. Wet Mount Techniques and concentration methods by using salt and formol–ether solutions. Three hundred and eighty four cases (59.8%) were found infected with one more parasites. Most of the individuals were found infected with helminth (47.6%) as compared to intestinal protozoans (0.93%). Seventy two cases (11.2%) of the cases presented mixed infection with both intestinal protozoan and helminth parasites. The order of prevalence for intestinal helminth was Ancylostoma duodenale (n = 258, 40.1%), followed by Taeniasa ginata (n=96, 14.9%) Ascaris lumbricoides (n = 54, 8.40%) and Trichuris trichura (n=30, 4.60%). For intestinal protozoa, Entamoeba histolytica/dispar (n = 36, 5.64%) was the only protozoan detected. Mono-parasitism was higher than poly-parasitism. Family size income and education level were the factors significantly (P<0.05) associated in the parasites prevalence. Current research showed that IPIs are primarily the foodborne pathogens still an important public health problem in Pakistan. Effective control programs on parasitic diseases transfer and their associated factors are recommended.

Os manipuladores de alimentos desempenham um papel fundamental na transmissão de protozoários e helmintos parasitas patogenicamente importantes. Este estudo teve como objetivo avaliar a prevalência de protozoários patogênicos intestinais e helmintos parasitas entre manipuladores de alimentos na Universidade de Malakand, Lower Dir, Paquistão. Amostras de fezes foram coletadas de 642 manipuladores de alimentos (todos do sexo masculino) em um estudo transversal de janeiro a novembro de 2017. Técnicas de montagem úmida e métodos de concentração usando soluções de sal e formol-éter. Trezentos e oitenta e quatro casos (59,8%) foram encontrados infectados com mais um parasita. A maioria dos indivíduos foi encontrada infectada por helmintos (47,6%) em comparação com protozoários intestinais (0,93%). Setenta e dois casos (11,2%) dos casos apresentavam infecção mista com protozoários intestinais e helmintos parasitas. A ordem de prevalência de helmintos intestinais foi Ancylostoma duodenale (n = 258, 40,1%), seguido por Taeniasa ginata (n = 96, 14,9%) Ascaris lumbricoides (n = 54, 8,40%) e Trichuris trichura (n = 30, 4,60 %). Para protozoários intestinais, Entamoeba histolytica / dispar (n = 36, 5,64%) foi o único protozoário detectado. Monoparasitismo foi maior do que poliparasitismo. A renda familiar e o nível de escolaridade foram os fatores significativamente (P <0,05) associados na prevalência de parasitos. A pesquisa atual mostrou que os IPIs são principalmente os patógenos de origem alimentar, ainda um importante problema de saúde pública no Paquistão. Programas eficazes de controle da transferência de doenças parasitárias e seus fatores associados são recomendados.

PREVALENCE OF Entamoeba histolytica/Entamoeba dispar IN THE CITY OF CAMPINA GRANDE, IN NORTHEASTERN BRAZIL / Prevalência de Entamoeba histolytica/Entamoeba dispar na cidade de Campina Grande, Nordeste do Brasil

There is a clear need to perform epidemiological studies to find the true prevalence of Entamoeba histolytica around the world. The evaluation of this prevalence has been hindered by the existence of two different species which are morphologically identical, but genetically different, namely E. histolytica, which causes amebiasis, and E. dispar, which is non-pathogenic. In Brazil, the E. dispar has been detected in communities in the Southeastern (SE) and Northeastern (NE) regions with poor sanitation. However, individuals infected with E. histolytica have been identified in other regions. There is an absence of reports on the prevalence of these parasites in the state of Paraíba, which also has areas with poor sanitary conditions where a high prevalence of the E. histolytica/E. dispar complex has been detected in children from urban slums. The present study evaluated the prevalence of E. histolytica and E. dispar in 1,195 asymptomatic children between two and 10 years of age, living in a sprawling urban slum in Campina Grande, in the state of Paraíba, in Northeastern Brazil. These children were examined and their feces samples were analyzed microscopically. A total of 553 children tested positive for the E. histolytica/E. dispar complex, and 456 of the positive samples were tested with the E. histolytica II® ELISA kit. All 456 samples were negative for the presence of the adhesin E. histolytica specific antigen. The evidence suggests that in this community E. histolytica is absent and E. dispar is the dominant species.

A prevalência mundial de Entamoeba histolytica não está bem estabelecida. Este fato deve-se à complicação derivada da existência de duas espécies morfologicamente idênticas, mas geneticamente diferentes: a E. histolytica que causa amebíases e a E. dispar descrita como não patogênica. No Brasil, em comunidades com precárias condições sanitárias e endêmicas para várias parasitoses, localizadas nas regiões Sudeste (SE) e Nordeste (NE), somente E. dispar tem sido encontrada, porém outras regiões, apresentam indivíduos infectados por E. histolytica. Na região agreste do Estado da Paraíba (NE) que apresenta as mesmas precárias condições sanitárias, não tem sido reportada prevalência específica destes parasitos, embora fosse encontrada alta prevalência do complexo E. dispar/E. histolytica em crianças em favela urbana. O presente estudo foi realizado em favela da cidade de Campina Grande, Estado da Paraíba, onde 1.195 crianças de dois a 10 anos sem sintomatologia foram examinadas. Amostras de fezes destas crianças foram analisadas microscopicamente, encontrando-se 553 positivas para o complexo E. dispar/E. histolytica. Do total de amostras positivas, 456 foram submetidas à pesquisa do antígeno especifico para E. histolytica pelo teste ELISA E. histolytica II®,obtendose resultado negativo para a presença do antígeno adesina específico de E. histolytica, em todas as amostras testadas. Os resultados sugerem que nesta comunidade não há infecção por E. histolytica, e que E. dispar é a espécie dominante na região.

Frequency of amoebiasis and other intestinal parasitoses in a settlement in Ilheus City, State of Bahia, Brazil

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. .

Laboratory diagnosis of amebiasis in a sample of students from southeastern Brazil and a comparison of microscopy with enzyme-linked immunosorbent assay for screening of infections with Entamoeba sp.

Introduction: Epidemiological studies on amebiasis have been reassessed since Entamoeba histolytica and E. dispar were first recognized as distinct species. Because the morphological similarity of these species renders microscopic diagnosis unreliable, additional tools are required to discriminate between Entamoeba species. The objectives of our study were to compare microscopy with ELISA kit (IVD®) results, to diagnose E. histolytica infection, and to determine the prevalence of amebiasis in a sample of students from southeastern Brazil. Methods: In this study, diagnosis was based on microscopy due to its capacity for revealing potential cysts/trophozoites and on two commercial kits for antigen detection in stool samples. Results: For 1,403 samples collected from students aged 6 to 14 years who were living in Divinópolis, Minas Gerais, Brazil, microscopy underestimated the number of individuals infected with E. histolytica/E. dispar (5.7% prevalence) compared with the ELISA kit (IVD®)-based diagnoses (15.7% for E. histolytica/E. dispar). A comparison of the ELISA (IVD®) and light microscopy results returned a 20% sensitivity, 97% specificity, low positive predictive value, and high negative predictive value for microscopy. An ELISA kit (TechLab®) that was specific for E. histolytica detected a 3.1% (43/1403) prevalence for E. histolytica infection. Conclusions: The ELISA kit (IVD®) can be used as an alternative screening tool. The high prevalence of E. histolytica infection detected in this study warrants the implementation of actions directed toward health promotion and preventive measures. .

High occurrence of Entamoeba histolytica in the municipalities of Ariquemes and Monte Negro, State of Rondônia, Western Amazonia, Brazil / Alta ocorrência de Entamoeba histolytica nos municípios de Ariquemes e Monte Negro, estado de Rondônia, Amazônia Ocidental, Brasil

Introduction: Entamoeba histolytica infections were investigated in residents of the Ariquemes and Monte Negro municipalities in Rondônia State, Brazil. Methods: Stool samples of 216 individuals were processed by the spontaneous sedimentation method and analyzed by microscopy for detection of the E. histolytica/E. dispar complex, followed by the immunoassay method using an enzyme-linked immunosorbent assay-based kit for the E. histolytica stool antigen. Results: E. histolytica/E. dispar cysts were present in 61% (50/82) and 44% (59/134) of the samples from Ariquemes and Monte Negro respectively, with a significant difference in the occurrence of infection between the two populations [p < 0.05; χ2 = 5.2; odds ratio = 2.0 (1.1 - 3.6)]. The E. histolytica antigen detection rate was 36.6% (30/82) for stool samples from Ariquemes, and 19.4% (26/134) for stool taken from the residents of Monte Negro. The rate of the occurrence of amoebiasis was significantly higher in the population from Ariquemes [p < 0.05; χ2 = 7.8; odds ratio = 2.4 (1.2 - 4.7)]. Discussion: Due to the high occurrence of E. histolytica infected residents diagnosed in the region and the unavailability in local clinics of a test to distinguish between the two Entamoeba species, physicians should consider treating E. histolytica/E.dispar infections. Conclusion: The results indicate that E. histolytica infection is highly endemic in the studied areas. .

Introdução: Infecções por Entamoeba histolytica foram investigadas em moradores dos municípios de Ariquemes e Monte Negro, Rondônia, Brasil. Métodos: Amostras de fezes de 216 indivíduos foram processadas por microscopia óptica para detecção de cistos do complexo E. histolytica/E. dispar, seguido pelo método de imunoensaio utilizando kit de ensaio imunoenzimático para detecção específica de antígeno de E. histolytica. Resultados: Cistos de E. histolytica/E. dispar estavam presentes em 61% e 44% das amostras de Ariquemes e Monte Negro, respectivamente com diferença significativa na ocorrência da infecção entre as duas populações [p < 0,05; χ2 = 5,2; Odds relativa = 2,0 (1,1 - 3,6)]. A taxa de detecção de antígenos de E. histolytica nas amostras provenientes de Ariquemes foi de 36,6% e de 19,41% nas amostras de Monte Negro, sendo a ocorrência de amebíase significativamente maior na população de Ariquemes [p < 0,05; χ2 = 7,8; Odds relativa = 2,4 (1,2 - 4,7)]. Discussão: A elevada frequência da infecção por E. histolytica em residentes na região, bem como a indisponibilidade de avaliação clínica por testes específicos para distinção entre as duas espécies de Entamoeba, deve promover uma reflexão sobre o tratamento de infecções pelo complexo E. histolytica/E. dispar. Conclusão: Nas populações avaliadas foram detectadas elevadas ocorrências de E. histolytica. .

Prevalence and characters of Entamoeba histolytica infection in Saudi infants and children admitted with diarrhea at 2 main hospitals at south Jeddah: a re-emerging serious infection with unusual presentation

In this study, Entamoeba histolytica had high prevalence and unusual presentation by affecting high proportion of infants under 1 year; severe clinical manifestations, and laboratory findings that were known to be usually encountered in invasive amebiasis as significant leukocytosis for age, neutrophilic leukocytosis for age, and positive C-reactive protein were found among more than 50% of admitted Saudi infants and children with E. histolytica infection in our locality. E. histolytica can be a re-emerging serious infection when it finds favorable environmental conditions and host factors which are mainly attributed to inadequate breastfeeding in this study. This may occur in any other area of the world with the same risk factors, so we must be ready to tackle it with effective and more powerful preventive measures.

Breast-Feeding Protects Infantile Diarrhea Caused by Intestinal Protozoan Infections

This study investigated the effect of breast-feeding in protection against protozoan infection in infants with persistent diarrhea. Infants were classified into 2 groups; 161 breast-fed infants and the same number of non-breast-fed infants. Microscopic examinations of stool were done for detection of parasites and measuring the intensity of infection. Moreover, serum levels of IgE and TNF-alpha were measured by ELISA. Cryptosporidium spp., Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Blastocystis sp. were demonstrated in infants with persistent diarrhea. The percentage of protozoan infections was significantly lower in breast-fed infants than that in the non-breast-fed infants. The levels of IgE and TNF-alpha were significantly lower in the breast-fed group than in the non-breast-fed group. There were significant positive associations between the serum levels of IgE and TNF-alpha and the intensity of parasite infection in the breast-fed group. It is suggested that breast-feeding has an attenuating effect on the rate and intensity of parasite infection.

Nested PCR reveals elevated over-diagnosis of E. histolytica in Barcelona, Venezuela / Nested PCR revela elevado sobrediagnóstico de E. histolytica en Barcelona, Venezuela

The aim of this study was to identify the presence of Entamoeba histolytica and E. dispar by nested PCR in children attending the “Dr. Luis Razetti” Hospital, Barcelona, Anzoátegui State. Of the 1,141 fecal samples coproparasitologically evaluated by conventional microscopy, 150 were diagnosed positive for E. histolytica in 0-10 year-old-children, of both sexes. The signs, symptoms and a full coproparasitological report were obtained from all of these and nested PCR was performed to identify E. histolytica and E. dispar. The conventional microscopy results showed a diagnostic frequency of E. histolytica in 13.2% of the cases, of which 79.3% were positive only for this pathogen. However, nested PCR showed that of these, only 28% (42/150) were actually infected by Entamoeba spp., revealing a high over-diagnosis of E. histolytica. We also identified 9.3% E. histolytica, 4% E. dispar and 4.7% mixed infections. Diarrhea was the most common symptom, followed by abdominal pain and fever. Bloody stools were statistically associated with E. histolytica, but were also found for E. dispar infections. This study demonstrates that molecular techniques complementary to conventional methods enable the correct identification of Entamoeba spp., thus contributing to an improved epidemiological assessment of these parasites and implementation of the appropriate treatment.

Esta investigación planteó detectar por nested PCR Entamoeba histolytica y E. dispar en niños del Hospital “Dr. Luis Razetti” de Barcelona, estado Anzoátegui y su asociación con síntomas clínicos. De 1.141 muestras fecales evaluadas parasitológicamente por microscopía convencional, 150 fueron positivas a E. histolytica en niños de 0-10 años y de ambos sexos. Se obtuvo información de signos, síntomas y reporte parasitólogico completo de cada uno de los pacientes y se realizó nested PCR para identificar E. histolytica y E. dispar. Los resultados de la microscopía convencional demostraron una frecuencia de diagnóstico de E. histolytica del 13,2%. En el 79,3% de estas positivas se reportó esta especie como único patógeno. Sin embargo, la nested PCR evidenció que sólo 28,0% (42/150) de las mismas presentaron infecciones por Entamoeba, evidenciándose un elevado sobrediagnóstico de E. histolytica. Además se identificaron 9,3% infecciones por E. histolytica, 4,0% E. dispar, y 4,7%infecciones mixtas. La diarrea fue el síntoma más común, seguido de dolor abdominal y fiebre. La presencia de sangre demostró asociación estadísticamente significativa con E. histolytica, pero también se reportó en infecciones por E. dispar. Este estudio demuestra que las técnicas moleculares complementarias a los métodos convencionales, permiten la identificación correcta de especies de Entamoeba, contribuyendo con una mejor evaluación epidemiológica de estos parásitos y la aplicación adecuada del tratamiento.

Diferenciación del complejo Entamoeba histolytica/Entamoeba dispar mediante Gal/GalNAc-lectina y PCR en aislamientos colombianos / Differentiation of entamoeba histolytica from entamoeba dispar using Gal/GalNAc-lectin and polymerase chain reaction

Background: Entamoeba histolytica and Entamoeba dispar are morphologically identical. However, the former is highly pathogenic and the latter is not. Aim: To differentiate Entamoeba histolytica from Entamoeba dispar through ELISA and PCR techniques in Colombian isolates from feces. Material and Methods: Descriptive study of Colombian fecal samples from 53 males and 47 women, that were positive for the complex E. histolytica/E. dispar on light microscopy. Positive samples were cultured on Robinson medium to isolate trophozoites. The presence of specific Gal/ GalNAc-lectin was determined by ELISA and polymerase chain reaction in genomic DNA, using the combination of three nucleotides that recognize a variable region of 16S small subunit ribosomal RNA, generating a 166 base pair (bp) product for E. histolytica and 752 pb product for E. dispar. Results: After verification, only eight of the 100 samples were positive for the complex E. histolytica/E. dispar and were cultivated. Isolates were obtained in six cultures, one corresponded to E. histolytica and six to E. dispar. Conclusions: The presence of E. histolytica/E. dispar complex was largely overestimated with light microscopy. In the few samples where isolates were obtained, the technique described differentiated between both strains.

Validation and utilization of PCR for differential diagnosis and prevalence determination of Entamoeba histolytica/Entamoeba dispar in Salvador City, Brazil

Amoebiasis is an infection caused by Entamoeba histolytica and is a potential health risk in countries in which health barriers are inappropriate. Since the discovery of Entamoeba dispar, the prevalence of amoebiasis has been modified. OBJECTIVE: This study has standardized the PCR technique applied for the diagnosis of different species of the E. histolytica/E. dispar complex and has evaluated the prevalence of infection among patients attending private and public clinical laboratories in Salvador City, Bahia State, Brazil. RESULTS: Analysis of 52,704 stool samples by microscopic examination demonstrated that 1,788 (3.4 percent) were positive for the E. histolytica/E. dispar complex and infection occurred more often in samples originated from public clinical laboratories (5.0 percent) than those that came from private laboratories (3.2 percent). PCR performed in approximately 15 percent (262) E. histolytica/E. dispar complex positive samples, randomly chosen, amplified 227 samples (86.6 percent), all of them positive for E. dispar. The non-amplified 35 samples (13.4 percent) were also negative for E. histolytica-specific galactose adhesin. Moreover, to exclude a probable infection caused by E. hartmanni, morphometric analysis demonstrated that non-amplified samples had cyst sizes comparable to E. histolytica/E. dispar (>10 µm). CONCLUSION: The absence of amplification of these samples indicates the presence of PCR inhibitors in the stool samples or the presence of DNA from Entamoeba species other than E. dispar, E. histolytica or E. hartmanni.

PCR Diagnosis of Entamoeba histolytica Cysts in Stool Samples

Amebiasis is a protozoan disease caused by Entamoeba histolytica and a potential health threat in areas where sanitation and hygiene are inappropriate. Highly sensitive PCR methods for detection of E. histolytica in clinical and environmental samples are extremely useful to control amebiasis and to promote public health. The present study compared several primer sets for small subunit (SSU) rDNA and histone genes of E. histolytica cysts. A 246 bp of the SSU rDNA gene of pure cysts contained in phosphate-buffered saline (PBS) and in stool samples was successfully amplified by nested PCR, using the 1,147-246 bp primer set, of the primary PCR products which were pre-amplified using the 1,147 bp primer as the template. The detection limit of the nested PCR using the 1,147-246 primer set was 10 cysts in both groups (PBS and stool samples). The PCR to detect histone gene showed negative results. We propose that the nested PCR technique to detect SSU rDNA can be used as a highly sensitive genetic method to detect E. histolytica cysts in stool samples.

Neonatal amoebiasis.

The authors report a case of neonatal amebiasis presenting with vomiting, refusal to feeds, abdominal distension and mucoid stools. The diagnosis was made on the basis of clinical appearance of stools and the presence of Entameba Histolytica. The purpose of this report is to alert to the possibility of amoebiasis in newborns, if baby presents with NEC like picture in an endemic area and to send the stool sample immediately to examine for trophozoites, especially because the diarrheal stool starts autolyzing within 30 min of defecation. This 14-day-old newborn, who was possibly infected with orally given jaggery solution is presented. He was successfully treated with intravenous tinidazole.

Detección y diferenciación de Entamoeba histolytica y Entamoeba dispar mediante reacción en cadena de la polimerasa en individuos de una comunidad del Estado Zulia, Venezuela / Detection and differentiation of Entamoeba histolytica and Entamoeba dispar by polymerase chain reaction in a community in Zulia State, Venezuela

Differential identification of Entamoeba histolytica and Entamoeba dispar is essential for both appropriate patient treatment and epidemiological purposes. To determine the prevalence of these amoeba infections in Santa Rosa de Agua (Maracaibo, Zulia State, Venezuela), a PCR assay using specific primers for each species was standardized and applied. 204 stool samples were analyzed through direct microscopic examination with SSF (0.85 percent) and lugol, formol-ether concentration, and PCR. Under direct microscopy, 42 individuals (20.58 percent) presented the E. histolytica/E. dispar complex. Meanwhile PCR showed 47 positive cases for these amoebas: 22 E. histolytica (10.78 percent), 16 E. dispar (7.84 percent), and 9 (4.41 percent) mixed infections. There was no significant difference in the presence of E. histolytica and/or E. dispar according to either gender or age. There were no cases of these amoebas in children under 2 years of age. Observed frequency of E. histolytica (31/204) shows the endemic nature of amoeba infection in this community.

La identificación diferencial de Entamoeba histolytica y Entamoeba dispar es esencial para un tratamiento adecuado del paciente y con fines epidemiológicos. Para determinar la prevalencia de E. histolytica y E. dispar se estandarizó y aplicó un ensayo de PCR, utilizando oligonucleótidos específicos para cada especie. 204 muestras de heces de individuos de la comunidad de Santa Rosa de Agua (Municipio Maracaibo, Estado Zulia, Venezuela), fueron analizadas a través del examen directo con SSF (0,85 por ciento) y lugol, concentrado de formol-éter y PCR. Al examen microscópico, 42 individuos (20,58 por ciento) presentaron formas evolutivas del complejo E. histolytica/E. dispar; mientras que la técnica de PCR evidenció un total de 47 casos positivos a estas amibas; de los cuales 22 eran portadores de E. histolytica (10,78 por ciento), 16 (7,84 por ciento) de E. dispar y 9 (4,41 por ciento) presentaron infección mixta. No hubo diferencia significativa al relacionar las variables sexo y presencia de E. histolytica y/o E. dispar, ni con los grupos etarios. No existieron casos de estas amibas, en los menores de 2 años. La frecuencia observada de E. histolytica (31/204), demuestra el carácter endémico de la amibiasis en esta comunidad.

Effects of antacid therapy in asymptomatic patients with presence of amoeba in stool report.

Amoebic infection caused by the protozoan parasite Entamoeba histolytica is a prevalent infection in the developing countries. Milder form of this infection is associated with loose stool, flatulence and borborygmi, may or may not be associated with pain in abdomen and treated symptomatically by some physicians by antacid. To find out the effects of antacid (sorbacid) therapy in patients with amoeba in stools by examining the changes in the stool report, a study was conducted among 25 patients enrolled in the study with complaints of "gas" in the abdomen with stool reports positive for amoeba. Antacid (sorbacid) in a dose of one teaspoonful (5 ml) was given three times a day for 3 days and stool examination was repeated. The report showed a significant reduction in the amoeba and mucus in stool (p<0.05) and a trend towards reduction in the presence of occult blood. Other parameters in stool reports did not change. Moreover, all the patients gave the history of passing formed stools and no complaints of "gas" in abdomen thus providing the symptomatic benefit. Antacids may have some beneficial effects in amoebiasis. More studies are required to confirm the above finding and to find out the place of antacid as an adjuvant therapy along with the standard anti-amoebic drugs.

Comparison of multiplex-PCR and antigen detection for differential diagnosis of Entamoeba histolytica

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 percent) 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.

Implantação e avaliação do diagnóstico diferencial entre Entamoeba histolytica e Entamoeba dispar em amostras fecais / Implementation and evaluation of the differential diagnosis of Entamoeba histolytica and Entamoeba dispar in fecal samples

A amebíase é uma infecção causada pela Entamoeba histolytica e representa um risco em potencial à saúde, em quase todos os países onde as barreiras sanitárias são inadequadas. É a segunda causa de mortalidade entre as parasitoses, alcançando em torno de 100.000 óbitos anuais. Com a descoberta da Entamoeba dispar, organismo comensal morfologicamente idêntico e geneticamente distinto da E. histolytica, a prevalência da infecção tem sido modificada. Neste estudo foi padronizada a reação em cadeia da polimerase para diagnóstico específico das amebas do complexo E. histolytica/E. dispar e aplicada para avaliar a prevalência da infecção em indivíduos atendidos em laboratórios da rede privada e pública de Salvador-BA. Amostras fecais de 52.704 pacientes, provenientes de 27 postos de coleta distribuídos em várias localidades, foram submetidas a exames coproparasitológicos. As amostras positivas para o complexo E. histolytica/E. dispar (n= 262) tiveram seus cistos concentrados por meio da técnica de formol-éter para posterior extração do DNA e diagnóstico através da PCR. Foi observada uma prevalência de 3.4 por cento para o complexo E. histolytica/E. dispar, sendo mais freqüente nas amostras provenientes do serviço público de saúde (5.0 por cento) do que naquelas do serviço privado (3.2 por cento). Através da PCR foi demonstrado que 86.6 por cento destes pacientes estavam verdadeiramente infectados pela E. disparo. Para o restante dos pacientes (14.4 por cento), a PCR foi negativa tanto para E. histolytica como para E. disparo. No ensaio imunoenzimático foi confirmado que estes pacientes não estavam infectados pela E. histolytica e o estudo morfométrico mostrou que o tamanho dos cistos é compatível com as amebas do complexo, afastando a possibilidade de infecção por E. hartmanni. Possivelmente, a presença de inibidores enzimáticos nas fezes diminuiu a sensibilidade da PCR. No entanto, é uma metodologia eficaz para...

Ocorrência de Entamoeba histolytica/Entamoeba dispar em pacientes ambulatoriais de Recife, PE / Occurrence of Entamoeba histolytica/Entamoeba dispar in ambulatory patients of Recife, PE

Este trabalho teve como objetivo determinar a ocorrência das espécies Entamoeba histolytica/Entamoeba dispar em amostras clínicas de pacientes ambulatoriais de Pernambuco. Neste estudo, foi utilizado o teste imunoenzimático específico para Entamoeba histolytica, que entre os 213 pacientes não identificou nenhuma amostra fecal positiva. Estes resultados confirmam Entamoeba dispar é a espécie dominante nesta região.

The objective this study was to determine the occurrence of the species Entamoeba histolytica/Entamoeba díspar in clinical samples of ambulatory patients in Pernambuco. A specific assay for Entamoeba histolytica was used in this study, which identified no positive fecal samples among the 213 patients. These results confirm that E. dispar is the dominant species in Pernambuco State.

Amoebic renal cyst: a case report

Entamoeba histolytica can infect any organ of the body, but only one case of renal involvement has been reported till now in the literature. We report a rare case of amoebic renal cyst in a 78-yearshowing favorable outcome with metronidazole treatment and therapeutic drainage.

Comparative evaluation of hexokinase isoenzyme typing and antigen detection for differentiation of Entamoeba histolytica and Entamoeba dispar.

Entamoeba histolytica, the causative organism of invasive amebiasis is a potential pathogen, while asymptomatic infection is caused by E. dispar. Differentiation of the species is not possible on the basis of morphological characters by microscopic examination. In the present study an attempt has been made to differentiate E. histolytica from E. dispar in 45 isolates obtained from culture and direct stool samples respectively on the basis of hexokinase isoenzyme analysis and Tech Lab ELISA. A 100% correlation was found between these two techniques. However, Tech Lab E. histolytica antigen detection test was found to be both rapid and technically simple. Its use in diagnosis and epidemiological studies is recommended.