Chronic urticaria associated with Blastocystis hominis infection.

Urticaria is a skin rash with several etiologic factors, including infectious agents. Blastocystis hominis is an intestinal protozoan parasite that has been linked to urticaria and skin lesions. The aim of this work was to investigate the association between B. hominis infection and chronic urticaria. In a case-control study, stool samples were obtained from 94 patients with chronic urticaria as case group and 285 healthy individuals as control group. Urticaria activity score 7 (UAS7) was used to score the severity of urticaria, classified as mild, moderate and intense. All stool samples underwent routine stool examinations, as well as polymerase chain reaction (PCR) for the detection of B. hominis. Molecular detection was carried out using the small subunit ribosomal RNA (SSU-rRNA) gene and the parasite subtypes were determined by sequencing. The rate of B. hominis infection was 21.3% (20 out of 94) and 17.2% (49 out of 285) between the case and control groups, respectively (p = 0.463). Three subtypes of B. hominis, including ST-1, ST-2 and ST-3, were detected in the case and control groups (ST-1 = 30% vs. 8.3%, ST-2 = 40% vs. 25% and ST-3 = 30% vs. 66.6% in the case and control group, respectively), which was statistically significant (p = 0.00001). However, no statistical differences were found between the severity of the urticaria and the B. hominis subtypes (p = 0.533). This study revealed a higher prevalence (but not significant) of B. hominis infection among patients with urticaria than healthy individuals. However, the results did not find a significant association between the subtypes of B. hominis and the severity of urticaria.

Irritable Bowel Syndrome Associated with Blastocystis hominis or Without Relationship to It? A Case-Control Study and Minireview.

BACKGROUND: Blastocystis hominis (B. hominis) is a protozoan parasite that has a worldwide distribution. Some studies have suggested a link between B. hominis and the development of irritable bowel syndrome (IBS). The objective of this study was to determine the prevalence of B. hominis in patients with IBS compared to healthy individuals. MATERIAL AND METHODS: A total of 65 stool samples from patients with IBS and 65 samples from healthy individuals in northern Iran were examined. The samples were tested using various methods including direct smear, formalin ether sedimentation and culture to detect the presence of B. hominis. Additionally, polymerase chain reaction (PCR) was performed on all culture-positive isolates to confirm the results and identify the genotype. RESULTS: B. hominis was detected in 15.38% of IBS patients and 9.2% of the healthy group. The culture in RPMI1640 was found to be better than the formalin ether and direct smear methods. Positive samples were confirmed using the molecular method. No significant difference was observed in the order of B. hominis infection between the two groups. CONCLUSIONS: The results of our study indicate that no significant difference was observed in the order of B. hominis infection between IBS patients and healthy groups. Therefore, further study is necessary to determine the potential pathogenic effects of this parasite and its role in causing IBS.

Improved diagnosis of gastrointestinal infections using a semi-automated multiplex real-time PCR for detection of enteropathogens.

Introduction. The identification of enteropathogens is critical for the clinical management of patients with suspected gastrointestinal infection. The FLOW multiplex PCR system (FMPS) is a semi-automated platform (FLOW System, Roche) for multiplex real-time PCR analysis.Hypothesis/Gap Statement. FMPS has greater sensitivity for the detection of enteric pathogens than standard methods such as culture, biochemical identification, immunochromatography or microscopic examination.Aim.The diagnostic performance of the FMPS was evaluated and compared to that of traditional microbiological procedures.Methodology. A total of 10 659 samples were collected and analysed over a period of 7 years. From 2013 to 2018 (every July to September), samples were processed using standard microbiological culture methods. In 2019, the FMPS was implemented using real-time PCR to detect the following enteropathogens: Shigella spp., Salmonella spp., Campylobacter spp., Giardia intestinalis, Entamoeba histolytica, Blastocystis hominis, Cryptosporidum spp., Dientamoeba fragilis, adenovirus, norovirus and rotavirus. Standard microbiological culture methods (2013-2018) included stool culture, microscopy and immunochromatography.Results. A total of 1078 stool samples were analysed prospectively using the FMPS from July to September (2019): bacterial, parasitic and viral pathogens were identified in 15.3, 9.71 and 5.29 % of cases, respectively. During the same period of 6 years (2013-2018), the proportion of positive identifications using standard microbiological methods from 2013 to 2018 was significantly lower. A major significant recovery improvement was observed for all bacteria species tested: Shigella spp./enteroinvasive Escherichia coli (EIEC) (P <0.05), Salmonella spp. (P <0.05) and Campylobacter spp. (P <0.05). Marked differences were also observed for the parasites G. intestinalis, Cryptosporidium spp. and D. fragilis.Conclusion. These results support the value of multiplex real-time PCR analysis for the detection of enteric pathogens in laboratory diagnosis with outstanding performance in identifying labile micro-organisms. The identification of unsuspected micro-organisms for less specific clinical presentations may also impact on clinical practice and help optimize patient management.

Acute gastroenteritis due to Blastocystis hominis in an adolescent boy.

Acute gastroenteritis with persistent vomiting, high degree fever and blood streaking stools often suggests bacterial aetiology in children. Authors report a 13-year-old boy presenting with acute watery diarrhoea with persistent vomiting, fever of 103°F, abdominal cramps and blood streaking stools who failed to show any response to parenteral third-generation cephalosporin for 72 hours. The stool examination revealed numerous cystic and amoeboid forms of Blastocystis hominis Metronidazole was started and the boy promptly responded within 24 hours. There was no recurrence of symptoms then onwards. The case highlights the crucial stool examination in case of acute diarrhoeal disease for rare aetiology.

Distribution of Intestinal Parasites Detected between September 2011-2018 at Dokuz Eylül University Medical Faculty Hospital.

OBJECTIVE: Intestinal parasitic diseases are important public health problems in our country as well as in the world. In this study, intestinal parasites were investigated in patients admitted to Dokuz Eylül University Hospital (DEUH) with various gastrointestinal system complaints. METHODS: Patients (n=18460) who were referred to the DEUH Central Parasitology Laboratory between January 2011 and December 2018, were included in the study. Fecal samples were examined with Nativ-lugol method and then formol ethyl-acetate precipitation method was applied. Trichrome and kinyoun acid-fast stainings were performed on the necessary samples. Demographic data of the patients were obtained from the hospital's and laboratory's information operating system. RESULTS: One or more parasites were detected in 6% (1128) of 18460 patients examined. The mean age of the patients with parasites was 39.7 (±23.1) years, of which 53.3% were male and 47.6% were female. The distribution of parasites detected were as follows; 4.8% (879) Blastocystis hominis, 0.7% (135) amoebas other than Entamoeba histolytica/dispar, 0.4% (70) Giardia intestinalis, 0.3% (49) Enterebius vermicularis, 0.1% (21) Entamoeba histolytica/dispar, and 0.01% (10) other rare parasites. CONCLUSION: Our study shows that intestinal parasitic infections are still an important public health problem in our region and that there is a decrease in their incidence.

Distribution and molecular analysis of Blastocystis subtypes from gastrointestinal symptomatic and asymptomatic patients in Iran.

INTRODUCTION: Blastocystis is a common intestinal parasite of human and animal hosts. The parasite has 17 subtypes, and among those at least nine subtypes (ST1-ST9) are found in human hosts. OBJECTIVE: The aim of the present study was to investigate the presence of different subtypes of Blastocystis spp. among the patients referred to Velayat hospital of Qazvin province, Iran. METHODS: Overall, 864 stool samples were examined by using formalin-ethyl acetate concentration method and Trichrome staining. All specimens were cultured in clotted fetal bovine medium. Later, DNA extraction and PCR amplification of 18S ribosomal RNA gene region was conducted and phylogenetic tree constructed. RESULTS: The results revealed 7.9% (68/864) of the study population were infected with Blastocystis. Intestinal symptoms were observed in 61% (36/59) of individuals positive for Blastocystis, with abdominal pain in 58% (21/36) of cases which was more frequent than other intestinal signs. No significant relationship was observed among the study variables. By molecular and phylogenetic analysis, three subtypes ST1 (45%), ST2 (30%) and ST3 (23%) of parasite were identified. CONCLUSION: This study showed ST1 subtype was the predominant subtype among the positive specimens, meanwhile the highest haplotype and nucleotide diversity were clarified in ST3 subtype.

Intestinal Parasites Infections among HIV Infected Children Under Antiretrovirals Treatment in Yaounde, Cameroon.

BACKGROUND: Intestinal parasitic infections are among the most common communicable diseases worldwide, particularly in developing countries. Human immunodeficiency virus (HIV) causes dysregulation of the immune system through the depletion of CD4+ T lymphocytes which gives rise to opportunistic infections. METHODOLOGY: A cross-sectional study was conducted from January to October 2018. Stool and blood samples were collected from participants aged 1 to 19. Stool samples were analyzed for intestinal parasites. Blood samples were analyzed for HIV and CD4 + T cell counts. RESULTS: Out of 214 children enrolled, 119 (55.6%) were HIV infected and 95 (44.4%) were HIV non-infected. All infected children were on antiretroviral treatment (ART). The prevalence of intestinal parasites was 20.2% in HIV infected and 15.8% in non-infected children. Among the 119 HIV infected children, 33 (27.7%) of them had a CD4+ T cell count less than 500 cells/mm3, and amongst them 5.9% had CD4+ T cell count less than 200 cells/mm3. Among HIV infected children, Cryptosporidium spp. was frequently detected, 7/119 (5.9%), followed by Giardia lamblia 5/119 (4.2%) then Blastocystis hominis 3/119 (2.5%) and Entamoeba coli 3/119 (2.5%). Participants on ART and prophylactic co-trimoxazole for >10 years had little or no parasite infestation. CONCLUSIONS: Although ART treatment in combination with prophylactic co-trimoxazole reduces the risk of parasitic infection, 20.2% of HIV infected children harbored intestinal parasites including Cryptosporidium spp. Stool analysis may be routinely carried out in order to treat detected cases of opportunistic parasites and such improve more on the life quality of HIV infected children.

Higher prevalence of Blastocystis hominis in healthy individuals than patients with gastrointestinal symptoms from Ahvaz, southwestern Iran.

BACKGROUND: Blastocystis, a common intestinal protozoan of humans and animals, infected more than 1 billion people around the world. This enteric protozoan is frequently reported in both healthy individuals and patients with gastrointestinal (GI) symptoms. METHODS: Three hundred and forty-five fecal samples including 151 GI patients and 194 healthy individuals were examined by microscopy, culture and PCR-sequencing techniques to determine Blastocystis frequency and subtype (ST) variation. RESULTS: The occurrence of Blastocystis was detected 56 (16.2%) and 85 (24.6%) by microscopy, culture and PCR methods, respectively. Out of the 85 positive patients, 60 (70.6%) were asymptomatic and 25 (29.4%) were symptomatic. The results of 41 successfully sequenced isolates identified 8 (19.5%), 8 (19.5%), and 25 (61.0%) ST1, ST2, and ST3, respectively. CONCLUSION: This study has found that Blastocystis was more common in healthy individuals than GI patients. Another finding was that no correlation was found between clinical symptoms and Blastocystis STs.

Metagenomics for broad and improved parasite detection: a proof-of-concept study using swine faecal samples.

Efficient and reliable identification of emerging pathogens is crucial for the design and implementation of timely and proportionate control strategies. This is difficult if the pathogen is so far unknown or only distantly related with known pathogens. Diagnostic metagenomics - an undirected, broad and sensitive method for the efficient identification of pathogens - was frequently used for virus and bacteria detection, but seldom applied to parasite identification. Here, metagenomics datasets prepared from swine faeces using an unbiased sample processing approach with RNA serving as starting material were re-analysed with respect to parasite detection. The taxonomic identification tool RIEMS, used for initial detection, provided basic hints on potential pathogens contained in the datasets. The suspected parasites/intestinal protists (Blastocystis, Entamoeba, Iodamoeba, Neobalantidium, Tetratrichomonas) were verified using subsequently applied reference mapping analyses on the base of rRNA sequences. Nearly full-length gene sequences could be extracted from the RNA-derived datasets. In the case of Blastocystis, subtyping was possible with subtype (ST)15 discovered for the first known time in swine faeces. Using RIEMS, some of the suspected candidates turned out to be false-positives caused by the poor status of sequences in publicly available databases. Altogether, 11 different species/STs of parasites/intestinal protists were detected in 34 out of 41 datasets extracted from metagenomics data. The approach operates without any primer bias that typically hampers the analysis of amplicon-based approaches, and allows the detection and taxonomic classification including subtyping of protist and metazoan endobionts (parasites, commensals or mutualists) based on an abundant biomarker, the 18S rRNA. The generic nature of the approach also allows evaluation of interdependencies that induce mutualistic or pathogenic effects that are often not clear for many intestinal protists and perhaps other parasites. Thus, metagenomics has the potential for generic pathogen identification beyond the characterisation of viruses and bacteria when starting from RNA instead of DNA.

Evaluation of a Flotation Adapted Parasep® for Stool Ova and Parasite Examination.

Stool ova and parasite examination using concentration methods remains the gold standard for the investigation of digestive parasitosis. Recently, single-use filtration devices have been marketed for stool concentration sedimentation methods such as MIF or Bailenger, which improve the analytical quality by avoiding contact with feces. In this study, the Parasep® device was adapted to the Faust technique flotation method. In addition, the performance between conventional techniques (MIF concentration and Faust) and techniques using this device was evaluated on 25 formalin-preserved stools and 3 fresh stools. With the Parasep device, the main parasites (protozoa or helminths) were isolated, and the technical requirements such as hygiene control for the operator and realization according to good laboratory practice were improved due to the filtration device.

A Comprehensive Retrospective Study: Intestinal Parasites in Human in Van Province

Objective: The aim of present study was to retrospectively determine the prevalence of intestinal parasites in patients, who were referred to Parasitology Laboratory in Van Yüzüncü Yil University, Faculty of Medicine during an 11-year period. Methods: Stool samples of 69633 individuals admitted to the outpatient clinics in the hospital were initially evaluated with native-Lugol, and then by flotation, sedimentation, trichrome staining, modified acid-fast staining and ELISA methods. Results: Twenty-four parasite species were identified in parasite-positive patients. At least one or more parasite species were found in 34.1% of all patients. The most commonly observed parasite was Blastocystis hominis (26.5%). Among pathogen parasites, Giardia intestinalis (G. intestinalis) was detected in 9.3%, Ascaris lumbricoides (A. lumbricoides) was detected in 2.5%, Entamoeba histolytica/Entamoeba dispar in 0.8%, Cystoisospora belli in 0.004%, Fasciola hepatica in 0.04%, Dicrocoelium dendriticum in 0.001%, Strongyloides stercoralis in 0.001% and hookworm in 0.001% of the patients. Conclusion: It was determined that, pathogen parasites such as G. intestinalis and A. lumbricoides were still observed at high rates in Van province, especially in children, and the problem of parasitosis is still continuing, although the prevalence of parasites has declined when compared to the previous years.

Prevalence of Parasitic Intestinal Infections Among Food Handlers in Qazvin, Iran

Objective: Food handlers play an important role in the production and distribution of parasitic contaminations in these societies. The aim of this study was to assess the prevalence of intestinal parasitic infections among the food handlers in Qazvin, Iran. Methods: Totally, 1530 stool samples were collected from food handlers in Qazvin, Iran. Direct feces examination and formalinethyl acetate concentration method followed by Trichrome staining were performed to detect the parasites. Results: The prevalence of intestinal parasites was 82 (5.4%) among food handlers. The species of protozoan parasites found were Blastocystis hominis, Giardia lamblia, Entamoeba coli, and Endolimax nana. The outbreaks of Blastocystis hominis (2.9%), and Endolimax nana (0.3%) were the most and the least protozoan infections observed among the specimens, respectively. Also, there was no helminthic infection detected among the samples. The prevalence of intestinal parasites among the food handlers, based on variables including sex, age, job, and education, did not differ, whereas the prevalence of intestinal symptoms was shown to be higher in infected food handlers (p<0.05). Conclusions: Despite a decrease in the incidence of intestinal parasites, the protozoan infections are still among the health concerns in these areas. Therefore, continuous monitoring and training of food handlers by local health authorities should be performed on a regular basis.

Geospatial analysis and epidemiological aspects of human infections with Blastocystis hominis in Mazandaran Province, northern Iran.

OBJECTIVES: Blastocystis hominis is a very common large intestinal protozoan with global prevalence in humans and non-human hosts. No precise statistics exist regarding the geographical distribution of Blastocystis that would enable the identification of high-risk communities. Therefore, the current research aimed to characterize the spatial patterns and demographic factors associated with B. hominis occurrence in northern Iran. METHODS: The current study was performed among 4,788 individuals referred to health centers in Mazandaran Province, from whom stool samples were obtained. Socio-demographic data were gathered using a questionnaire. Samples were examined by a direct wet mount, the formalin-ethyl acetate concentration technique, and trichrome staining. Moran local indicators of spatial association and a geographically weighted regression model were utilized to analyze the results. RESULTS: Generally, the infection rate of Blastocystis parasites was 5.2%, and was considerably higher in the age group of 10-14 years (10.6%) than in other age groups (p=0.005). Our data showed important associations between the occurrence of B. hominis and age, residence, job, contact with domestic animals, anti-parasitic drug consumption, and elevation above sea level (p<0.001). CONCLUSIONS: The current study characterized for the first time the infection rate and risk of B. hominis in the north of Iran, and produced a prediction map. It is expected that this map will help policymakers to plan and implement preventive measures in high-risk areas and to manage already-infected patients.

Irritable bowel syndrome in Egyptian patients: plausible risk factors and association with intestinal protozoa.

The pathogenesis of irritable bowel syndrome (IBS) is not yet clear. Our study suggested parasitic infection and other plausible risk factors among Egyptian IBS patients. We studied 40 IBS patients diagnosed according to Rome III criteria (Group I), 40 with other gastrointestinal symptoms (Group II) and 40 healthy controls (Group III). Stool samples were examined using direct wet smear, sedimentation technique, trichrome stain and immune-chromatographic tests for Cryptosporidium parvum. IBS patients displayed a significantly greater percentage of Blastocystis hominis infection (45%) than non-IBS patients (20%) and healthy controls (10%). Dientamoeba fragilis was identified in two IBS patients. Detection of B. hominis was independent of demographic characters, IBS subtype, Helicobacter pylori infection or medications, but with a positive association with a history of antibiotic intake with IBS.

Prevalence of non-pathogenic types of gastrointestinal protozoa in population in Slovakia and their potential importance in the aspect of public health.

The aim of the research was to determine the prevalence of non-pathogenic protozoa circulating in the human population of Slovakia. We particularly focused on the socially deprived areas with poor sanitation conditions, as they are one of the factors affecting the transmission of these infections. Within this study, 2760 people were coprologically screened for the presence of protozoan cysts. The analyzed group comprised 1173 men and 1587 women from different regions of Slovakia. The total prevalence (2.03%) of non-pathogenic protozoa species was determined. The prevalence of Entamoeba coli was 0.80%, the prevalence of Endolimax nana 0.58%, and the prevalence of Blastocystis hominis was 0.65%. The presence of non-pathogenic protozoa was more frequent in women than that in men, in all age groups. The highest incidence of Entamoeba coli was found in children aged one month - seven years (0.79%), the lowest in the age group of 19-88 years (0.66%). Endolimax nana was most frequent in 8-18 year-olds (0.95%), where the statistical significance was found (p<0.05). The prevalence of Blastocystis hominis by the age group ranged from 0.39 to 0.95%. We did not find any statistical significance (p>0.05) for Entamoeba coli, and similarly for Blastocystis hominis associated with the sex and age. Although the circulation of non-pathogenic protozoa in the human population is far from being limited to the developing countries, their occurrence is also frequent in the population of developed countries. Despite their controversial pathogenicity, they should not be neglected, particularly in the patients with gastrointestinal symptoms.

Distribution of Intestinal Parasites in Patients Hospitalized in Child Intensive Care Unit.

OBJECTIVE: The purpose of the present study was to investigate the distribution of intestinal parasites in patients hospitalized in a child intensive care unit. METHODS: The study was conducted on 150 patients between the ages of 2 months and 17 years between April 2016 and December 2016. Stool samples were tested by Native-Lugol, sedimentation (formol-ether solution), and acid fast method. Moreover, a questionnaire was used to obtain information about the socio-economic status of the patient, education level of the families, living conditions, and whether or not they have chronic illnesses. RESULTS: 40% of all patients were infected with one or more parasites 41.7% of girls and 38.2% of boys. In the present study, Giardia intestinalis (12.6%), Blastocystis hominis (12.6%), Entamoeba coli (7.3%), Cyclospora cayetanensis (5.3%), and Cryptosporidium spp. (2%) were detected. CONCLUSION: Statistical analysis was evaluated with the frequency of parasitism and revenue level, educational level of families, settlement area, whether there is a sewage network or not, whether animal husbandry is done or not, and source of water in home is from tap or well. The differences were not significantly. The possible reasons for the high rate of parasitosis, especially with G. intestinalis, E. coli, and B. hominis, are inadequate education, living in small houses with large numbers of people, sewage system, and lack of clean and safe drinking water.

Características clínicas y epidemiológicas de la parasitación intestinal por Blastocystis hominis / Clinical and epidemiological characteristics of intestinal parasite infection by Blastocystis hominis

Objetivos. Blastocystis hominis (B. hominis) es uno de los parásitos intestinales más frecuentemente aislados en el ser humano. Puede producir sintomatología gastrointestinal o, en la mayoría de los casos, permanecer asintomático. Existen dudas sobre el carácter patógeno del parásito. El objetivo de este estudio fue analizar las características clínicas y epidemiológicas de la parasitación por B. hominis, con y sin otras coparasitaciones. Pacientes y métodos. Estudio observacional retrospectivo de aislamientos de B. hominis en heces, desde octubre del 2004 hasta marzo del 2016 en una Unidad de Medicina Tropical. Se revisó a todos los pacientes con parasitación exclusiva, o no, por B. hominis. Resultados. Se estudió a 3.070 pacientes. En 570 (18%) se diagnosticó infección por B. hominis, de los que en 245 (43%) representó el único aislamiento; 325 (57%) presentaron otras coparasitaciones (Entamoeba hystolitica o dispar, Strongyloides stercoralis, uncinarias y Schistosoma sp.). El síntoma principal fue dolor abdominal (41,8%). En un 31,2% el parásito se detectó en el cribado de enfermedades importadas en pacientes asintomáticos. De los que recibieron tratamiento con metronidazol, un 78,2% mejoró y en el 82,6% los parásitos se negativizaron. Conclusiones. La parasitación por B. hominis es una de las enfermedades más frecuentes en nuestra Unidad de Medicina Tropical. La mayoría de los pacientes están asintomáticos o bien la clínica puede ser atribuida a otras parasitaciones. En aquellos casos en los que persisten los síntomas sin poder ser atribuidos a otras causas, es recomendable un tratamiento específico

Objectives. Blastocystis hominis (B. hominis) is one of the most common intestinal parasites isolated in humans. The parasite can cause gastrointestinal symptoms or, in most cases, remain asymptomatic. There are issues concerning the parasite's pathogenic character. The aim of this study was to analyse the clinical and epidemiological characteristics of the parasite infection by B. hominis, with or without other parasitic co-infections. Patients and methods. An observational retrospective study was conducted of B. hominis isolates in faeces from October 2004 to March 2016 in a tropical medicine unit. We reviewed all patients with a parasite infection, exclusively or not by B. hominis. Results. We studied 3070 patients, 570 (18%) of whom were diagnosed with B. hominis infection, which was the only isolate in 245 (43%) of the 570 patients. A total of 325 (57%) patients presented other parasitic co-infections (Entamoeba histolytic or Entamoeba dispar, Strongyloides stercoralis, hookworm and Schistosoma spp.). The main symptom was abdominal pain (41.8%). In 31.2% of cases, the parasite was detected in the imported diseases screening of asymptomatic patients. Of those who underwent treatment with metronidazole, 78.2% improved. The parasite was neutralised in 82.6% of the patients. Conclusions. Parasite infection by B. hominis is one of the most common diseases in our tropical medicine unit. Most patients are asymptomatic, or their symptoms can be attributed to other parasite infections. In those cases in which symptoms persist without being able to attribute them to other causes, a specific treatment is recommended

Un parásito emergente de patogenicidad controvertida, Blastocystis sp.: ¿Hay que tratar a todos los pacientes? / Blastocystis sp., an emerging parasite with controversial pathogenicity. Should all human cases be treated?

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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.

Evaluation of the Roche LightMix Gastro parasites multiplex PCR assay detecting Giardia duodenalis, Entamoeba histolytica, cryptosporidia, Dientamoeba fragilis, and Blastocystis hominis.

OBJECTIVES: Multiplex PCR assays offer highly sensitive and specific tools for the detection of enteric pathogens. This prospective study aimed at comparing the novel Roche LightMix Modular Assay Gastro Parasites (LMAGP) detecting Giardia duodenalis, Entamoeba histolytica, Cryptosporidium spp., Blastocystis hominis, and Dientamoeba fragilis with routine laboratory procedures. METHODS: Stool specimens (n = 1062 from 1009 patients) were consecutively examined by LMAGP, R-Biopharm Ridascreen enzyme immunoassays (EIAs) detecting G. duodenalis or E. histolytica/dispar, and microscopy of wet mounts. Discrepant results were analysed by in-house PCR. RESULTS: D. fragilis or B. hominis were detected by LMAGP in 131 (14.4%) and 179 (19.9%; 16 samples positive by microscopy; p < 0.0001) of 909 samples, respectively. Of 918 samples analysed for Cryptosporidium spp., six were positive by LMAGP (three could be confirmed by Kinyoun staining and one by in-house PCR). G. duodenalis was detected by LMAGP, EIA, or microscopy in 20, 16, or 9 of 1039 stool samples, respectively; all four samples missed by EIA were confirmed by in-house PCR. In total, 938 stool samples were analysed for E. histolytica/dispar. Nine of ten EIA-positive samples were negative by LMAGP but positive by in-house PCR for E. dispar. One E. histolytica infection (positive by both LMAGP and in-house PCR) was missed by EIA and microscopy. Parasites only detected by microscopy included Enterobius vermicularis eggs (n = 3) and apathogenic amoebae (n = 27). CONCLUSIONS: The data call for routine use of multiplex PCR assays for the detection of enteric protozoan parasites in laboratory diagnostics.