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Biology Nov 2022The human gastrointestinal microbiota contains a diverse consortium of microbes, including bacteria, protozoa, viruses, and fungi. Through millennia of co-evolution, the... (Review)
Review
The human gastrointestinal microbiota contains a diverse consortium of microbes, including bacteria, protozoa, viruses, and fungi. Through millennia of co-evolution, the host-microbiota interactions have shaped the immune system to both tolerate and maintain the symbiotic relationship with commensal microbiota, while exerting protective responses against invading pathogens. Microbiome research is dominated by studies describing the impact of prokaryotic bacteria on gut immunity with a limited understanding of their relationship with other integral microbiota constituents. However, converging evidence shows that eukaryotic organisms, such as commensal protozoa, can play an important role in modulating intestinal immune responses as well as influencing the overall health of the host. The presence of several protozoa species has recently been shown to be a common occurrence in healthy populations worldwide, suggesting that many of these are commensals rather than invading pathogens. This review aims to discuss the most recent, conflicting findings regarding the role of intestinal protozoa in gut homeostasis, interactions between intestinal protozoa and the bacterial microbiota, as well as potential immunological consequences of protozoa colonization.
PubMed: 36552252
DOI: 10.3390/biology11121742 -
PLoS Neglected Tropical Diseases Oct 2021The clinical significance of Blastocystis sp. and Dientamoeba fragilis in patients with gastrointestinal symptoms is a controversial issue. Since the pathogenicity of...
Investigation of neglected protists Blastocystis sp. and Dientamoeba fragilis in immunocompetent and immunodeficient diarrheal patients using both conventional and molecular methods.
INTRODUCTION
The clinical significance of Blastocystis sp. and Dientamoeba fragilis in patients with gastrointestinal symptoms is a controversial issue. Since the pathogenicity of these protists has not been fully elucidated, testing for these organisms is not routinely pursued by most laboratories and clinicians. Thus, the prevalence of these organisms and the subtypes of Blastocystis sp. in human patients in Turkey are not well characterized. This study aimed to determine the prevalence of Blastocystis sp. and D. fragilis in the diarrheic stool samples of immunodeficient and immunocompetent patients using conventional and molecular methods and to identify Blastocystis sp. subtypes using next generation sequencing.
MATERIAL AND METHODS
Individual stool specimens were collected from 245 immunodeficient and 193 immunocompetent diarrheic patients between March 2017 and December 2019 at the Gazi University Training and Research Hospital in Ankara, Turkey. Samples were screened for Blastocystis sp. and D. fragilis by conventional and molecular methods. Molecular detection of both protists was achieved by separate qPCRs targeting a partial fragment of the SSU rRNA gene. Next generation sequencing was used to identify Blastocystis sp. subtypes.
RESULTS
The prevalence of Blastocystis sp. and D. fragilis was 16.7% and 11.9%, respectively as measured by qPCR. The prevalence of Blastocystis sp. and D. fragilis was lower in immunodeficient patients (12.7% and 10.6%, respectively) compared to immunocompetent patients (21.8% and 13.5%, respectively). Five Blastocystis sp. subtypes were identified and the following subtype distribution was observed: ST3 54.4% (n = 37), ST2 16.2% (n = 11), ST1 4.4% (n = 3), ST6 2.9% (n = 2), ST4 1.5% (n = 1), ST2/ST3 11.8% (n = 8) and ST1/ST3 8.8% (n = 6). There was no statistically significant difference in the distribution of Blastocystis sp. subtypes between immunocompetent and immunodeficient patients.
CONCLUSION AND RECOMMENDATION
Our findings demonstrated that Blastocystis sp. and D. fragilis are commonly present in immunocompetent and immunodeficient patients with diarrhea. This study is the first to use next generation sequencing to address the presence of Blastocystis sp. mixed subtypes and intra-subtype variability in clinical samples in Turkey.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Blastocystis; Diarrhea; Dientamoeba; Feces; Female; High-Throughput Nucleotide Sequencing; Humans; Immunocompetence; Male; Middle Aged; Primary Immunodeficiency Diseases; Turkey; Young Adult
PubMed: 34613993
DOI: 10.1371/journal.pntd.0009779 -
Tropical Parasitology 2022() diagnosis is an intestinal protozoan parasite globally found in rural and urban areas and is attracting a growing interest. Its prevalence in stool varies from 0.2%...
INTRODUCTION
() diagnosis is an intestinal protozoan parasite globally found in rural and urban areas and is attracting a growing interest. Its prevalence in stool varies from 0.2% to more than 19% depending upon the population studied.
MATERIALS AND METHODS
This study was based on the examination of 100 stool samples of randomly referred cases in a rural area in Motobus district, Kafr El-Sheikh governorate, Egypt. Our aim was to investigate the presence of in stool of the examined individuals using conventional polymerase chain reaction (PCR) compared to wet mount and trichrome stain with confirmation of infection by transmission electron microscopy.
RESULTS
was detected in 13/100 of the stool samples examined using wet mount smears, while trichrome stain detected 17/100. Conventional PCR diagnosed 41 cases of in the studied group. A very good agreement was found between wet mount and trichrome stain for diagnosing , while there was fair agreement between conventional PCR and both microscopy methods. Transmission electron microscope was performed on pooled positive samples that revealed the internal structures of trophozoite with its characteristic nucleus.
CONCLUSIONS
PCR technique was superior to microscopy for the detection of . Trichrome stain remains vital for microscopic diagnosis.
PubMed: 36643979
DOI: 10.4103/tp.tp_93_21 -
Dientamoeba fragilis associated with microbiome diversity changes in acute gastroenteritis patients.Parasitology International Dec 2023This study examined the correlation between intestinal protozoans and the bacterial microbiome in faecal samples collected from 463 patients in New Zealand who were...
This study examined the correlation between intestinal protozoans and the bacterial microbiome in faecal samples collected from 463 patients in New Zealand who were diagnosed with gastroenteritis. In comparison to traditional microscopic diagnosis methods, Multiplexed-tandem PCR proved to be more effective in detecting intestinal parasites. Among the identified protozoans, Blastocystis sp. and Dientamoeba fragilis were the most prevalent. Notably, D. fragilis was significantly associated with an increase in the alpha-diversity of host prokaryotic microbes. Although the exact role of Blastocystis sp. and D. fragilis as the primary cause of gastroenteritis remains debatable, our data indicates a substantial correlation between these protozoans and the prokaryote microbiome of their hosts, particularly when compared to other protists or patients with gastroenteritis but no detectable parasitic cause. These findings underscore the significance of comprehending the contributions of intestinal protozoans, specifically D. fragilis, to the development of gastroenteritis and their potential implications for disease management.
Topics: Animals; Humans; Dientamoeba; Intestinal Diseases, Parasitic; Blastocystis; Gastroenteritis; Parasites; Feces
PubMed: 37482266
DOI: 10.1016/j.parint.2023.102788 -
Pathogens (Basel, Switzerland) Oct 2022The enteric protozoan parasites spp., and are-to various extents-contributors to the burden of gastrointestinal illness in high-income countries. Detection of these...
The enteric protozoan parasites spp., and are-to various extents-contributors to the burden of gastrointestinal illness in high-income countries. Detection of these pathogens by microscopy examination is challenging because of the limited sensitivity and need for specific staining procedures. We developed and optimised a new multiplex real-time PCR assay for the simultaneous detection of spp., and in clinical (stool) samples. The diagnostic performance of the assay was evaluated against a large panel of well-characterised DNA samples positive for spp. ( = 126), ( = 132) and ( = 49). The specificity of the test was assessed against a DNA panel from other intestinal or phylogenetically related parasites ( = 105) and faecal DNA from individuals without clinical manifestations ( = 12). The assay exhibited a diagnostic sensitivity of 0.90-0.97 and a diagnostic specificity of 1. The limit of detection was estimated for (1 oocyst) and (5 × 10 cysts). The method allowed the detection of four species (, , and ) and five assemblages (A-E) without cross-reacting with other parasites belonging to the phyla Amoebozoa, Apicomplexa, Euglenozoa, Microsporidia, Nematoda and Platyhelminthes. This newly developed multiplex real-time PCR assay represents a novel alternative for the rapid and accurate detection of , and in clinical settings.
PubMed: 36365028
DOI: 10.3390/pathogens11111277 -
International Journal of Molecular... Aug 2023Globally, over 3.5 billion people are infected with intestinal parasites each year, resulting in over 200,000 deaths. Three of the most common protozoan pathogens that...
Globally, over 3.5 billion people are infected with intestinal parasites each year, resulting in over 200,000 deaths. Three of the most common protozoan pathogens that affect the gastrointestinal tract of humans are spp., , and . Other protozoan agents that have been implicated in gastroenteritis in humans include , , , and the microsporidia and . Genetic Signatures previously developed a 3base™ multiplexed Real-Time PCR (mRT-PCR) enteric protozoan kit (EP001) for the detection of //, spp., , . , and . We now describe improvements to this kit to produce a more comprehensive assay, including , , and , termed EP005. The clinical performance of EP005 was assessed using a set of 380 clinical samples against a commercially available PCR test and other in-house nucleic acid amplification tests where commercial tests were not available. All methods provided at least 90% agreement. EP005 had no cross-reactivity against 82 organisms commonly found in the gut. The EP005 method streamlines the detection of gastrointestinal parasites and addresses the many challenges of traditional microscopic detection, resulting in cost savings and significant improvements in patient care.
Topics: Humans; Cryptosporidiosis; Cryptosporidium; Gastrointestinal Diseases; Communicable Diseases; Protozoan Infections; Giardia lamblia
PubMed: 37686192
DOI: 10.3390/ijms241713387 -
International Maritime Health 2023Poland has experienced increased economic migration since 2021. Large waves of migrants, mostly from Asian and African countries, are trying to get into the European...
BACKGROUND
Poland has experienced increased economic migration since 2021. Large waves of migrants, mostly from Asian and African countries, are trying to get into the European Union by crossing Poland's eastern border illegally. The influx of illegal migrants into Poland is the result of a policy adopted by the Belarusian and Russian regimes that are trying to provoke another migrant crisis in Europe. In the opinion of some Polish politicians illegal migration contributes to the spread of parasitic diseases in our country as many migrants arriving into Poland carry intestinal parasites. The aim of this study was to assess the prevalence of infections with intestinal parasites in the Polish Border Guard officers safeguarding Poland's eastern borders.
MATERIALS AND METHODS
Parasitological diagnostics was carried out between April and May 2023. The study involved 218 Polish Border Guard officers from the Podlaski Border Guard Unit (PBGU) and 209 officers from the Bug Border Guard Unit (BBGU), whose task is to patrol and safeguard Poland's border with Ukraine and Belarus. Faecal examinations were performed using three different light microscopy testing methods (direct smear, decantation, flotation) at the Department of Epidemiology and Tropical Medicine at the Military Institute of Medicine - National Research Institute, Warsaw, Poland.
RESULTS
Considered to be potentially pathogenic intestinal parasites were diagnosed in 20 out of 218 officers serving in the PBGU (8.7% infected with Blastocystis spp., 0.5% with Dientamoeba fragilis) and in 9 out of 209 officers serving in the BBGU (3.8% infected with Blastocystis spp., 0.5% with Dientamoeba fragilis). There were no infections with nematodes, cestodes or trematodes in the study participants. No correlation was found between a parasitic infection and the presence of diarrhoea or other gastrointestinal symptoms within 6 months prior to the study in both groups.
CONCLUSIONS
Although Polish Border Guard officers deployed to the eastern border are exposed to difficult environmental conditions and have frequent contacts (either directly or indirectly) with migrants arriving from countries which report high incidence of parasitic infections, the rates of infections with potentially pathogenic protozoa in officers from the PBGU and BBGU are low and mainly attributable to pathogens which are widespread in the general Polish population. Low rates of parasitic infections in officers serving in the border zone suggest that the epidemiological situation of parasitic diseases in East Poland is satisfactory and that the disease prevention strategies (including the use of personal protection gear) implemented by the Polish medical services are effective.
Topics: Humans; Poland; Intestinal Diseases, Parasitic; European Union; Military Personnel; Europe
PubMed: 37781943
DOI: 10.5603/imh.97185 -
Nutrients Aug 2022Obesity is an epidemic causing a metabolic health crisis. Herein, the interactions between the gut prokaryotic and eukaryotic communities, metabolic comorbidities and...
Obesity is an epidemic causing a metabolic health crisis. Herein, the interactions between the gut prokaryotic and eukaryotic communities, metabolic comorbidities and diet were studied. Stool samples from 56 subjects, 47 with type III obesity and 9 with type II obesity and cardiovascular risk or metabolic disease, were assessed for the richness, diversity and ecology of the bacterial gut community through metagenomics, together with the study of the presence of common unicellular eukaryote parasites ( sp., and ) by qPCR. Clinical information regarding metabolic comorbidities and non-alcoholic hepatic fatty liver disease was gathered. To assess the quality of the patients' diet, each participant filled in three dietary questionnaires. The most prevalent parasite sp. (46.4%), together with (8.9%), was found to be associated with higher mean diversity indexes regarding non-colonized subjects; the opposite of that which was observed in those with (16.1%). In terms of phyla relative abundance, with sp. and , very slight differences were observed; on the contrary, was related to an increase in Bacteroidetes and Proteobacteria, and a decrease in Firmicutes and Actinobacteria, presenting the lowest Firmicutes/Bacteroidetes ratio. At genus level, sp. and/or was accompanied with an increase in spp., and a decrease in spp., spp. and spp., while was associated with an increase in spp., and a decrease in spp., spp. and spp., and the highest spp./ spp. ratio. Participants with non-alcoholic hepatic fatty liver presented a higher Firmicutes/Bacteroidetes ratio, and those with type 2 diabetes displayed a significantly lower spp./ spp. ratio, due to an overrepresentation of the genus spp. The presence of parasites was associated with variations in the richness, diversity and distribution of taxa in bacterial communities, confirming a gain in diversity associated with sp. and providing different functioning of the microbiota with a potential positive effect on comorbidities such as type 2 diabetes, insulin resistance and metabolic syndrome. Future basic and clinical studies should assess the beneficial or pathogenic effect of these eukaryotes on obese subjects and focus on deciphering whether they may imply a healthier metabolic profile.
Topics: Animals; Bacteria; Blastocystis; Diabetes Mellitus, Type 2; Feces; Humans; Obesity, Morbid; Parasites
PubMed: 35956387
DOI: 10.3390/nu14153211 -
Tropical Medicine and Infectious Disease Sep 2021While the prevalence of intestinal parasitic infections (IPI) has been most commonly studied in African and Asian populations, less is known about the prevalence rates... (Review)
Review
While the prevalence of intestinal parasitic infections (IPI) has been most commonly studied in African and Asian populations, less is known about the prevalence rates of IPI in European children, as well as the potential risk factors that favor the spread of parasites. We aimed to review published evidence on the prevalence rates of IPI in children residing in Europe, and to quantitatively synthesize the results of published studies. We searched Medline from 1 January 2015 to 1 April 2021 to address the most recently published prevalence patterns of IPI in European children. Random-effects meta-analyses were performed by type of IPI infection, age group and sex, depending on data availability. Of the 967 potentially relevant articles, eight eligible cross-sectional studies were included in this analysis, yielding a sample of 3376 children (0-19 years). The overall prevalence rate was 5.9% for any IPI in children residing in European countries. was the most commonly detected parasite yielding a prevalence rate of 10.7%. Other parasites included and . Studies focusing on specific types of parasites showed prevalence rates ranging from 1.3% for to 68.3% for . Despite the scarce literature, the present review showed relatively low prevalence rates of IPI in Europe. Future studies accounting for proper diagnostic methods used for the detection of parasites and including information on potential sociodemographic factors, such as travelling history and history of immigration, are needed to guide clinicians about which children to test, as well as when and how to test children for IPI.
PubMed: 34564544
DOI: 10.3390/tropicalmed6030160 -
International Journal of Environmental... Nov 2019Drinking water outbreaks occur worldwide and may be caused by several factors, including raw water contamination, treatment deficiencies, and distribution network...
Drinking water outbreaks occur worldwide and may be caused by several factors, including raw water contamination, treatment deficiencies, and distribution network failure. This study describes two drinking water outbreaks in Finland in 2016 (outbreak I) and 2018 (outbreak II). Both outbreaks caused approximately 450 illness cases and were due to drinking water pipe breakage and subsequent wastewater intrusion into the distribution system. In both outbreaks, the sapovirus was found in patient samples as the main causative agent. In addition, adenoviruses and (outbreak I), and noroviruses, astroviruses, enterotoxigenic and enterohemorragic (ETEC and EHEC, respectively) and (outbreak II) were detected in patient samples. Water samples were analyzed for the selected pathogens largely based on the results of patient samples. In addition, traditional fecal indicator bacteria and host-specific microbial source tracking (MST) markers (GenBac3 and HF183) were analyzed from water. In drinking water, sapovirus and enteropathogenic (EPEC) were found in outbreak II. The MST markers proved useful in the detection of contamination and to ensure the success of contaminant removal from the water distribution system. As mitigation actions, boil water advisory, alternative drinking water sources and chlorination were organized to restrict the outbreaks and to clean the contaminated distribution network. This study highlights the emerging role of sapoviruses as a waterborne pathogen and warrants the need for testing of multiple viruses during outbreak investigation.
Topics: Bacterial Infections; Disease Outbreaks; Drinking Water; Feces; Finland; Humans; Virus Diseases; Wastewater; Water Microbiology; Water Purification
PubMed: 31717479
DOI: 10.3390/ijerph16224376