Blastocystis in Swiss children: a practical approach.

Blastocystis is a parasite with a worldwide distribution and a varying prevalence in different countries. The pleomorphic nature of the protozoon and the lack of understanding a possible pathogenesis have led to confusion regarding its clinical significance. The aim of the study was to shed light on clinical characteristics of pediatric patients in Swiss children with a positive stool sample for Blastocystis, in order to provide recommendations for a practical approach for the clinician to know whom, when, and how to test. This is a retrospective study of pediatric patients, whose stool has been tested positive for Blastocystis in the last 10 years in northern Switzerland. A total of 4047 stool samples, belonging to 1887 different patients, were analyzed; 240 stool samples (of 160 patients) were tested positive for Blastocystis. On average, 2.2 (CI 1.98-2.35) stool samples per patient were analyzed, of which 1.48 (CI 1.36-1.61) were positive for Blastocystis. In 63% abdominal pain was the leading symptom, while in 17.5% it was an accidental finding without symptoms. There was a high significance in correlation of abdominal pain and chronicity (p < 0.0001) but none in diarrhea (p = 0.082) nor nausea/vomiting or other symptoms and chronicity. Followed by Entamoeba coli (8%), 26.3% of the patients with Blastocystis had a co-infection with another parasite, mostly Endolimax nana (13%).Conclusion: Carriage of Blastocystis is common; therefore, only children/teenagers at risk for a symptomatic Blastocystis infection should be tested. There is a good correlation between Blastocystis and chronic abdominal pain. Children with abdominal symptoms persisting over 4 weeks should have two different stool samples analyzed. No screening after travels/immigration is recommended.What is Known:• Blastocystis has a worldwide distribution.• The clinical significance is unclear.What is New:• Based on retrospective data, we recommend to only test children/teenagers with chronic abdominal pain for Blastocystis.• Two different stool samples should be examined by microscopy; serological investigations are not warranted.

[Current view on Blastocystis species: clinical forms, diagnosis and treatment].

The symptomatic form of Blastocystis spp. infection not only with mild diarrhea or dysentery-like syndrome, but also with the development of severe ulcerative necrotic lesions of the intestine. Meanwhile, the pathogenicity of these microorganisms should not be exaggerated, due to majority asymptomatic cases or infection transmission with minor impaired bowel function.

Blastocystis hominis transmission by non-potable water: a case report in Italy.

In the reported case, a 41-year-old Italian man came to the clinician's observation reporting cramps, bloating and watery diarrhoea a few days after drinking water indicated as unpotable from a fountain in a farm area. The medical suspicion was directed at both gluten intolerance and enteric infection, eventually of waterborne origin. Gluten intolerance was investigated by intestinal biopsy and excluded, while stool analyses ruled out infective bacteriological or viral agents and parasites. Subsequently, a persistent eosinophilia was revealed and a parasitological analysis was again suggested, planning for a more sensitive molecular method. Therefore, a multiplex-PCR of enteric protozoa species DNA was performed on an intestinal biopsy and faecal samples revealing only Blastocystis hominis protozoa, subsequently typed as subtype 1 by RFLP-PCR method. B. hominis is an anaerobic protozoa found in the human and animal intestinal tract, recently associated with a pathogenic role characterized by chronic development. Since blastocystosis has been demonstrated as a waterborne infection, a sample of water matrix was analysed, revealing the B. hominis subtype 1 DNA inside. A probable water transmission of Blastocystis infection has been demonstrated in this case report. Only a probiotic treatment based on Saccharomyces boulardii was administered to the patient and this apparently resolved the infection. In summary, the case described here is a chronic blastocystosis of possible waterborne origin, controlled by assuming a yeast treatment.

Blastocystis spp.: avances, controversias y desafíos futuros / Blastocystis spp.: Advances, controversies and future challenges

Blastocystis spp. es el protista intracelular que se detecta con mayor frecuencia en muestras de materia fecal humana; las tasas de infección pueden superar el 20% en países en vías de desarrollo. El hallazgo de este parásito en heces de diversas especies animales sugiere su potencial zoonótico. La relevancia clínica y el papel patógeno de Blastocystis spp. en el tracto intestinal son inciertos. Varias son las publicaciones que lo reconocen como agente etiológico de desórdenes intestinales como diarrea, enfermedad inflamatoria intestinal y colitis ulcerosa, aunque la patogenicidad de este parásito no ha sido probada. Este amplio rango de respuestas a la infección podría estar relacionado con la diversidad genética de los aislamientos provenientes de hospedadores infectados.

Blastocystis spp. is the most common protozoan detected in human stool samples. In developing countries, infection rates are higher than 20%. The presence of this parasite in the feces of several host species suggests its zoonotic potential. The clinical relevance and the pathogenic role of Blastocystis spp. in the intestinal tract remain unclear. There are several clinical reports that recognize it as the etiologic agent of several intestinal disorders such as diarrhea, inflammatory bowel disease and ulcerative colitis, although the pathogenicity of this parasite has not been proved yet. This wide range of clinical manifestations could be related to the genetic diversity exhibited by this parasite.

[Blastocystis spp.: Advances, controversies and future challenges]. / Blastocystis spp.: avances, controversias y desafíos futuros.

Blastocystis spp. is the most common protozoan detected in human stool samples. In developing countries, infection rates are higher than 20%. The presence of this parasite in the feces of several host species suggests its zoonotic potential. The clinical relevance and the pathogenic role of Blastocystis spp. in the intestinal tract remain unclear. There are several clinical reports that recognize it as the etiologic agent of several intestinal disorders such as diarrhea, inflammatory bowel disease and ulcerative colitis, although the pathogenicity of this parasite has not been proved yet. This wide range of clinical manifestations could be related to the genetic diversity exhibited by this parasite.

Current status of Blastocystis: A personal view.

Despite Blastocystis being one of the most widespread and prevalent intestinal eukaryotes, its role in health and disease remains elusive. DNA-based detection methods have led to a recognition that the organism is much more common than previously thought, at least in some geographic regions and some groups of individuals. Molecular methods have also enabled us to start categorizing the vast genetic heterogeneity that exists among Blastocystis isolates, wherein the key to potential differences in the clinical outcome of Blastocystis carriage may lie. In this review we summarize some of the recent developments and advances in Blastocystis research, including updates on diagnostic methods, molecular epidemiology, genetic diversity, host specificity, clinical significance, taxonomy, and genomics. As we are now in the microbiome era, we also review some of the steps taken towards understanding the place of Blastocystis in the intestinal microbiota.

[Blastocystis hominis- parasites or commensals? ]. / Blastocystis hominis - komensal czy patogen?

Blastocystis hominis (B. hominis) is a cosmopolitan pro- tozoa which parasitizes the human large intestine. This parasite had been considered to be commensal of the large intestine for a long time, because even an intense invasion may be asymptomatic. However, this species is now being regarded as a parasitic organism. In this paper the latest data concerning the epidemiology, diagnostics and treatment of B. hominis invasion have been cited and discussed.

[Infection by Blastocystis: a review]. / Infección por Blastocystis.

Blastocystis sp. is an anaerobic unicellular micro-organism belonging to the kingdom Chromista, frequently found in the digestive tracts of humans and animals, the pathogenic role of which continues being controversial for human beings. Its genetic classification, which shows nine sub-types, some of which seem to have a role in cases with gastrointestinal symptomathology, opens a new field for research. In this article, an extensive revision is carried out which includes the historic development of the parasite, its taxonomy, epidemiology, morphology, vital cycle, as well as biochemical, cytochemical and genetic aspects, the pathogenic role in contrast with different variables which include the sub-types, quantity, response to the treatment and association with other pathogens. Finally, the clinical and therapeutic aspects are also reviewed.

Infección parasitaria múltiple importada en una paciente pedriátrica: patología del niño inmigrante / Imported parasite infection in a pediatric patient: disease in the immigrant child

Las infecciones parasitarias constituyen un importante problema de salud en los países en vías de desarrollo. La Organización Mundial de la Salud ha referido recientes progresos en la prevención y el control de estas infecciones. Los niños procedentes de adopciones internacionales constituyen hoy en día un porcentaje significativo de la población, con una patología propia característica de su país de origen. Los pediatras que trabajamos en países desarrollados estamos siendo testigos de un gran movimiento poblacional, con la consiguiente aparición de enfermedades importadas en la población infantil que cubrimos. Se presenta el caso de una niña de 12 años, aparentemente sana y asintomática, procedente de Etiopía, en proceso de adopción internacional, a la que se le diagnostica una coinfección por parásitos intestinales, identificándose en las heces huevos de Schistosoma manosni, Hymeolepis nana, Entamoeba histolytica, Blastocystis hominis y Enteobius vermicularis. El estudio se realiza a petición de la familia, por tener conocimiento de un caso de esquistosomiasis diagnosticado en una niña que llegó a nuestro país junto con su hija

Parasitic infections are an important health problem in the developing world. The World Health Organization has presented recent advances in the prevention and control of these infections. A considerable number of immigrants children arriving in developed countries do so through international adoptions. These children can be carriers for diseases characteristics of their countries of origin. The pediatricians working in the countries that take them in are witnessing a major population movement and an increase in the incidence of imported diseases among our pediatric population. We present the case of an apparently healthy and asymptomatic twelve-year-old girl who was brough from Ethiopia in international adoption. The analysis of a fecal sample revealed the presence of coinfection with Schistosoma mansoni, Hymeolepis nana, Entamoeba histolytica, Blastocystis hominis y Enteobius vermicularis. The family requested the study because they had learned of a case of intestinal schistosomiasis infection in a girl who had arrived in Spain from Ethiopia together with their daughter

Tratamiento comparativo de la infección por Bastocystis horminis con Metronidazol y Secnidazol / Comparative treatment of the infection for Blastocystis hominis with metronidazol and Secnidazol

Para evaluar el efecto de metronidazol y secnidazol en el tratamiento de la infección por Blastocystis hominis, se realizó un estudio prospectivo en 60 pacientes con tal diagnóstico. El diagnóstico fue establecido clínicamente y confirmado con examen parasitológico seriado en heces. Se tuvo subgrupos de estudio: A, B y C. A: Recibieron metronidazol 250 mg. desayuno, almuerzo y comida por cinco días. B: Recibieron metronidazol 750 mg. desayuno, almuerzo y comida por siete días. C: Recibieron secnidazol 2 gramos como dosis única. Al mes de tratamiento se hizo control de examen parasitológico seriado de heces y varios controles clínicos posterapia. Los síntomas clínicos más frecuentemente encontrados fueron: flatulencia, dolor abdominal, dispepsia, malestar general, diarrea. En cuanto a la evolución después de la terapia: Fue favorable en la mayoría de casos: 75 por ciento en el grupo A, 80 por ciento en el grupo B y C. Se encontró negativización del examen en: 60 por ciento (A), 50 por ciento (B), 65 por ciento (C). Hubo disminución de la población de Blastocystis hominis en el examen de heces 20 por ciento (A), 30 por ciento (B), 20 por ciento (C). Los efectos adversos más frecuentes fueron: dolor epigástrico, disbacteriosis, naúsea, diarrea. Podemos plantear que si se presenta infección por Blastocystis hominis sintomática esta puede ser tratada con Secnidazol o Metronidazol, pués se ha encontrado mejoría en los grupos sometidos a tratamiento. Deben realizarse o llevarse a cabo estudios prospectivos a doble ciego para poder reforzar este hallazgo.