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.

The absence of Blastocystis spp. is associated with the HE severity and dysbiosis in the gut microbiota.

PACK-CXL with rose bengal demonstrated pronounced antiamoebic activity against A.castellanii. Further in vitro and in vivo studies are needed to confirm this finding.

This epidemiological study assesses the occurrence of enteric parasites in 4303 patients attended at two public hospitals in Ankara (Turkey) during 2018–2019. Microscopy was used as a screening test. Giardia duodenalis was also identified using a commercial ELISA for the detection of parasite-specific coproantigens. Giardia-positive samples by microscopy/ELISA were confirmed by real-time PCR and characterized using a multilocus genotyping scheme. Blastocystis sp. was genotyped in a sample subset. Blastocystis sp. (11.1%, 95% CI 11.4‒14.8%) and G. duodenalis (1.56%, 95% CI 1.22‒1.96) were the most prevalent pathogens found. Cryptosporidium spp., Entamoeba histolytica and intestinal helminths were only sporadically (<0.5%) found. For G. duodenalis, sequence (n = 30) analyses revealed the presence of sub-assemblages AII (23.3%), discordant AII/AIII (23.3%) and mixed AII + AIII (6.7%) within assemblage A, and BIII (10.0%), BIV (3.3%) and discordant BIII/BIV (23.3%) within assemblage B. Two additional sequences (6.7%) were assigned to the latter assemblage but sub-assemblage information was unknown. No associations between G. duodenalis assemblages/sub-assemblages and sociodemographic and clinical variables could be demonstrated. For Blastocystis sp., sequence (n = 6) analyses identified subtypes ST1, ST2 and ST3 at equal proportions. This is the first molecular characterization of G. duodenalis based on MLG conducted in Turkey to date.

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Echinococcus granulosus larvasının insanlarda sebep olduğu kistik ekinokokkoz (KE), ülkemizde hayvancılığın yoğun olarak yapıldığı bölgelerde yaygın görülen ve tanı için klinisyen, radyolog ve mikrobiyologların multidisipliner yaklaşımını gerektiren bir zoonozdur. Enzim-linked immünassay (ELISA) ve indirekt hemaglütinasyon (IHA), hastaların tanısında ilk sırada tercih edilirken Western Blot (WB) testi daha çok doğrulama amacıyla kullanılmaktadır. Fakat serolojik testlerin hastalığın tanı ve takibinde tek başına kullanımı, değişken duyarlılık ve özgüllük oranları nedeniyle önerilmemekte, uygun tanı için birden fazla serolojik testin kullanımı gerekmektedir. Bu çalışmada, Aralık 2015-2016 tarihleri arasında Gazi Üniversitesi Tıp Fakültesi Mikrobiyoloji Laboratuvarı'na KE şüphesiyle gönderilen hasta serumlarında IHA yöntemiyle titrasyon veren örneklerin doğrulama testi olarak kabul edilen WB yöntemi ile değerlendirilmesi ve iki test arasındaki tutarlılığın saptanması amaçlanmıştır.

In order to study the diversity, phylogenetic relationships and distribution of marsh frogs of the Pelophylax ridibundus complex in Kazakhstan and northwest China, we conducted phylogeographic analyses of 125 samples from 53 localities using the mtDNA ND2 and COI genes and the SAI nuclear gene sequences. Phylogenetic inference of mtDNA revealed three main lineages—sister lineages Balkhash and Syrdarya (as the Central Asian P. sp. novum), and the Anatolian P. cf. bedriagae, while from nDNA data, we additionally detected the western form, P. ridibundus. According to mtDNA data, the mean genetic distances between P. sp. novum and two other forms of marsh frogs was more than 5%. Genetic homogeneity within populations of the Syrdarya lineage and P. cf. bedriagae is characterized by low nucleotide diversity and high haplotype diversity. Demographic analyses of the lineages showed past population expansions of the Balkhash and the Syrdarya forms. Divergence from the most recent ancestor had occurred in the Early Pleistocene period (2.46 Mya) for the Balkhash and the Syrdarya lineages, and 1.27 Mya for the P. cf. bedriagae. Our findings provide a first investigation of the lineage diversification and population dynamics of the Central Asian marsh frogs and will be useful for further taxonomic implications and conservational actions.

Blastocystis is an obligate anaerobic microbial eukaryote that frequently inhabits the gastrointestinal tract. Despite this prevalence, very little is known about the extent of its genetic diversity, pathogenicity, and interaction with the rest of the microbiome and its host. Although the organism is morphologically static, it has no less than 28 genetically distinct subtypes (STs). Reports on the pathogenicity of Blastocystis are conflicting. The association between Blastocystis and intestinal bacterial communities is being increasingly explored. Nonetheless, similar investigations extending to the metabolome are non-existent.Using established NMR metabolomics protocols in 149 faecal samples from individuals from South Korea (n = 38), Thailand (n = 44) and Turkey (n = 69), we have provided a snapshot of the core metabolic compounds present in human stools with (B+) and without (B−) Blastocystis. Samples included hosts with gastrointestinal symptoms and asymptomatics. A total of nine, 62 and 98 significant metabolites were associated with Blastocystis carriage in the South Korean, Thai and Turkish sample sets respectively, with a number of metabolites increased in colonised groups. The metabolic profiles of B+ and B− samples from all countries were distinct and grouped separately in the partial least squares-discriminant analysis (PLS-DA). Typical inflammation-related metabolites negatively associated with Blastocystis positive samples. This data will assist in directing future studies underlying the involvement of Blastocystis in physiological processes of both the gut microbiome and the host. Future studies using metabolome and microbiome data along with host physiology and immune responses information will contribute significantly towards elucidating the role of Blastocystis in health and disease.