The involvement of cytokine gene polymorphism in determining the vulnerability to Blastocystis and Helicobacter pylori co-infection in the Egyptian population.

AIMS: The present study aimed to identify any potential association between IL-1ß and TNF-α gene polymorphism and the risk of Blastocystis infection as well as co-infection of Blastocystis with Helicobacter pylori (H.pylori). METHODOLOGY: A total of 314 stool samples were collected and examined microscopically for the detection of parasitic infection. DNA was extracted from all samples and utilized to identify Blastocystis molecularly. Positive samples were used for H. pylori detection by rapid tests and PCR. Moreover, we investigate polymorphism in the TNF-α gene at position -1031T/C, -308 G/A, and IL-1ß at position +3954C/T using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. RESULTS: Out of the 314 stool samples, Blastocystis was detected in 93 (29.6 %); among them, 54 (58.1 %) had a mixed infection of Blastocystis with H. pylori. The TT genotype of the IL-1ß gene at position +3954 was significantly higher in Blasocystis-infected patients than in uninfected patients (17.2% vs. 6.3 %, P = 0.02), which might be considered a risk factor (OR = 3.2; CI =1.21-8.52). The TNF-α at position -1031 TT genotype was significantly higher in Blastocystis-infected patients than uninfected patients (44.1% vs. 10.8 %, P< 0.0001). The T allele (OR= 2.67; CI=1.51-4.72, P = 0.0008) might be considered a risk factor. The TNF- α at position -308 AA genotype is higher in Blasocystis infected than uninfected (17.2% vs 7.2 %, P = 0.03). TNF-α -308 AA (OR = 2.72; CI = 1.08-6.89) and A allele (OR= 1.46; CI= 0.797-2.66) might be considered risk factors. The TNF- α at position -308 G/A showed that the GG is the most frequent genotype in Blastocystis with H. pylori-positive patients with a significant association (P = 0.004), as well as the G allele (P = 0.02). The G allele (OR=1.924; CI= 1.071-3.454) might be considered a risk factor for co-infection of Blastocystis and H. pylori. CONCLUSION: SNPs (-1031 T/C and -308 G/A) of the TNF-α and (+3954 C/T) of the IL-1ß may be a useful marker in the assessment of the risk of Blastocystis infection, and TNF-α at position -308 G/A) may be a predictor for co-infection of Blastocystis with H. pylori.

The Significance of Opportunistic Parasitosis and Blastocystosis in Patients with Gastric Cancer: a Study with Control Group.

Objective: The aim of this study was to determine the prevalence of opportunistic parasites and Blastocystis spp. in patients with gastric cancer (CA) and to determine the significance of these parasite. Methods: The patient group and the control group were composed of 100 people each. The stool samples were examined under the microscope for intestinal parasites with the native-Lugol method. Then, samples were multiplied by formol-ethyl acetate method and stained with modified acid-fast method. Results: Intestinal parasite positivity was indicated in 14% of the gastric CA, and 2% of the healthy individuals (p=0.001). Blastocystis spp. (p=0.009) was identified in 11%, Cryptosporidium spp. was identified in 4%, G. intestinalis was identified in 2%, and C. cayetanensis was identified in 1% of the patient group. There were significant differences between the intestinal parasite positivity (p=0.012), abundant Blastocystis spp. positivity (p=0.041) and all Blastocystis spp. positivity (p=0.037) in patient and control groups. Most of the patients who were positive for parasites had diarrhea. Conclusion: Based findings, it was concluded that it would be beneficial to evaluate gastric CA patients, especially those with diarrhea, for intestinal parasites.

Prevalence of Blastocystis and Dientamoeba fragilis in diarrheal patients in Corum, Türkiye.

To investigate the prevalence of Blastocystis and Dientamoeba fragilis in diarrhea patients and healthy individuals in Corum, Türkiye, fecal samples from 92 diarrhea patients and 50 healthy individuals were collected and evaluated using direct microscopy and molecular methods to screen for bacteria, protozoa, and viruses. The prevalence of Blastocystis was 24.6% in total and more frequent in the healthy group (30.0%). The commonly detected STs (subtypes) were ST3 (40.0%) and ST2 (34.2%). The distribution of Blastocystis STs in the healthy and diarrheal groups did not show any difference in sex and age, but ST3 was detected more frequently in patients aged from 40 to 59 years (p < 0.05). Alleles 4 (8/12) and 2 (4/12) were present in ST1; 9 (3/5) and 12 (2/5) in ST2; 34 (9/14), 36 (3/14), and 38 (2/14) in ST3; and only allele 42 (2/2) in ST4. D. fragilis was present in 8.4% of the population. However, there was no statistically significant difference between the healthy and diarrheic groups (12.0% and 6.5%, respectively), neither with respect to age nor sex. Co-infection was 58.3% and was more frequent in healthy individuals (33.3%) than in diarrhea patients (25.0%). Blastocystis ST3 was the most common subtype detected, with D. fragilis at 33.3%. Salmonella, Shigella, or helminth eggs were not observed in all groups, but Entamoeba histolytica, Giardia intestinalis, Cryptosporidium, Rotavirus, Adenovirus, and Clostridium difficile toxin were found only in diarrhea patients. These findings support the hypothesis that Blastocystis and D. fragilis may be part of the healthy human gut microbiome.

Impact factors of Blastocystis hominis infection in persons living with human immunodeficiency virus: a large-scale, multi-center observational study from China.

BACKGROUND: Blastocystis hominis (Bh) is zoonotic parasitic pathogen with a high prevalent globally, causing opportunistic infections and diarrhea disease. Human immunodeficiency virus (HIV) infection disrupts the immune system by depleting CD4+ T lymphocyte (CD4+ T) cell counts, thereby increasing Bh infection risk among persons living with HIV (PLWH). However, the precise association between Bh infection risk and HIV-related biological markers and treatment processes remains poorly understood. Hence, the purpose of the study was to explore the association between Bh infection risk and CD4+ T cell counts, HIV viral load (VL), and duration of interruption in antiviral therapy among PLWH. METHODS: A large-scale multi-center cross-sectional study was conducted in China from June 2020 to December 2022. The genetic presence of Bh in fecal samples was detected by real-time fluorescence quantitative polymerase chain reaction, the CD4+ T cell counts in venous blood was measured using flowcytometry, and the HIV VL in serum was quantified using fluorescence-based instruments. Restricted cubic spline (RCS) was applied to assess the non-linear association between Bh infection risk and CD4+ T cell counts, HIV VL, and duration of interruption in highly active antiretroviral therapy (HARRT). RESULTS: A total of 1245 PLWH were enrolled in the study, the average age of PLWH was 43 years [interquartile range (IQR): 33, 52], with 452 (36.3%) being female, 50.4% (n = 628) had no immunosuppression (CD4+ T cell counts > 500 cells/µl), and 78.1% (n = 972) achieved full virological suppression (HIV VL < 50 copies/ml). Approximately 10.5% (n = 131) of PLWH had interruption. The prevalence of Bh was found to be 4.9% [95% confidence interval (CI): 3.8-6.4%] among PLWH. Significant nonlinear associations were observed between the Bh infection risk and CD4+ T cell counts (Pfor nonlinearity < 0.001, L-shaped), HIV VL (Pfor nonlinearity < 0.001, inverted U-shaped), and duration of interruption in HARRT (Pfor nonlinearity < 0.001, inverted U-shaped). CONCLUSIONS: The study revealed that VL was a better predictor of Bh infection than CD4+ T cell counts. It is crucial to consider the simultaneous surveillance of HIV VL and CD4+ T cell counts in PLWH in the regions with high level of socioeconomic development. The integrated approach can offer more comprehensive and accurate understanding in the aspects of Bh infection and other opportunistic infections, the efficacy of therapeutic drugs, and the assessment of preventive and control strategies.

Higher amoebic and metronidazole resistant forms of Blastocystis sp. seen in schizophrenic patients.

BACKGROUND: Blastocystis sp. is one of the most common colonisers of the intestinal tract that demonstrate strong interaction with accompanying gut bacteria. Previously, the protozoan isolated from individuals with irritable bowel syndrome (IBS) showed altered phenotypic features suggesting that it can be triggered to become pathogenic. Previous studies reported altered gut microbiota and high prevalence of Blastocystis sp. in schizophrenia patients. However, the phenotypic characteristics of Blastocystis sp. isolated from individuals with SZ have yet to be described. METHODS: In this study, faecal samples from 50 patients with severe schizophrenia (SZ) and 100 non-schizophrenic (NS) individuals were screened for Blastocystis sp. INFECTION: Positive isolates were subjected to genotypic and phenotypic characterization. RESULTS: We found that 12 out of 50 (24%) SZ and 5 out of 100 (5%) NS individuals were detected Blastocystis sp. positive using both in vitro culture and PCR method with no significant association to age and gender. Out of the 15 sequenced isolates, ST3 was the most prevalent subtype (66.7%) followed by ST1 (20%) and ST6 (13.3%). The isolates from SZ individuals demonstrated significant slower growth rate (34.9 ± 15.6 h) and larger range of cell diameter (3.3-140 µm). We detected higher amoebic forms and metronidazole resistance among SZ isolates with variation in cell surface glycoprotein where 98% of cells from SZ showed consistent medium to high binding affinity (+ 2 to + 3) to Concavalin A staining compared to NS isolates that demonstrated only 76% high lectin (+ 3) binding affinity. Cysteine and serine protease levels were predominantly found among SZ isolates. We also demonstrate the presence of metalloprotease in Blastocystis sp. especially among NS isolates. Introduction of solubilised antigens from SZ isolates increased the cell proliferation of HCT116 cells by two fold when compared to NS isolates. CONCLUSION: Our findings demonstrated Blastocystis sp. isolated from SZ individuals showed variation in phenotype specifically in morphology and drug resistance. The findings indicate that the gut environment (SZ and NS) and treatment of SZ could have influenced the phenotype of Blastocystis sp.

The regulatory function of Blastocystis spp. on the immune inflammatory response in the gut microbiome.

Blastocystis spp. is a unicellular organism that resides in digestive tract of various vertebrates, with a worldwide distribution and a variable prevalence. For many years, Blastocystis spp. was considered a cyst of a flagellate, a fungus, or a saprophyte yeast of the digestive tract; in 1996, it is placed in the group of stramenopiles (heterokonts). Since its new classification, many questions have arisen around this protist about its role as a pathogen or non-pathogen organism. Recent evidence indicates that Blastocystis spp. participates in the immune inflammatory response in the intestinal microbiome generating an anti-inflammatory response, showing a lower concentration of fecal inflammatory markers in infected human hosts. Here, we review recent findings on the regulatory function of Blastocystis spp. in the immune inflammatory response to comprehend the purpose of Blastocystis spp. in health and disease, defining if Blastocystis spp. is really a pathogen, a commensal or even a mutualist in the human gut microbiome.

Molecular investigation of Blastocystis sp. and its subtypes in cancer patients under chemotherapy in Aegean region, Turkey.

Blastocystis sp. is a common enteric protist found in humans and many other animals. Although the clinical relevance of Blastocystis sp. is currently fully unknown for humans, the prevalence of Blastocystis and subtypes are investigated in immunocompetent individuals presenting with symptoms like diarrhea or immunocompromised individuals including cancer patients. In this comprehensive study, the prevalence of Blastocystis sp. and subtypes were investigated in patients (n=94) with different types of malignant solid tumors using PCR targeting SSU rDNA gene and sequencing. All patients were undergoing chemotherapy and had diarrhea. According to obtained results, 46 patients were found to be Blastocystis positive and the molecular prevalence was detected as 48.9%. Among the positive specimens, 43 (43/46; 93.5%) of them were successfully subtyped. ST4 was the most predominant subtype and detected in 24 (55.8%) patients, followed by ST1 (11 patients, 25.6%) and ST3 (8 patients, 18.6%). In the colon cancer group, which had the highest number of patients, Blastocystis sp. was detected with a higher prevalence rate of 61.5% compared with the prevalence rate (48.9%) of all patients. Interestingly, ST3 was not detected in any of this patient group in contrast to ST4 and ST1. In conclusion, high prevalence of the Blastocystis in the immunocompromised patient groups shows the susceptibility of this patient group against any other infectious agents.

Serological levels of cytokines in irritable bowel syndrome (IBS) patients and non-IBS subjects with and without Blastocystis spp. infection.

The objectives of the present study were to investigate the prevalence of Blastocystis spp. and to determine the levels of some pro-and anti-inflammatory cytokines in patients with irritable bowel syndrome (IBS) and without Blastocystis infection in comparison with non-IBS control individuals. Stool samples were collected from 250 IBS patients and 100 samples from controls, examined for the presence of Blastocystis and the percentage of infection was recorded. After that each group subdivided into two groups: non-IBS subjects not infected with Blastocystis (group 1), non-IBS subjects infected with Blastocystis (group 2), IBS patients not infected with Blastocystis (group 3), and IBS patients infected with Blastocystis (group 4). After that, blood samples were collected from 10 participant from each group and sera were separated and used for measuring the levels of the selected pro- and anti-inflammatory cytokines using ELISA method. The results revealed that about 60% of IBS patients were found infected with Blastocystis while 22% of the subjects in the control group were found infected with this parasite and the difference between the two groups was highly significant (P=0.0001). In addition, the results revealed that IBS patients with Blastocystis showed significantly higher In addition, the results revealed that IBS patients with Blastocystis showed significantly higher serum IL-6 (P=0.0004), IL-10 (P=<0.0001), IL-18 (P=0.0001), IFN-γ (P=<0.0001), and TNF-α (P=<0.0001) when compared with the subjects in the control group. Similarly, the non-IBS subjects infected with Blastocystis showed significantly higher serum IL-6 (P=0.0032), IL-10 (P=0.0001), IL-18 (P=0.0002), IFN-γ (P=0.0001), and TNF-α (P=0.0001) in comparison with the subjects in the control group. In conclusion, the infection with Blastocystis has a significant impact on the levels of all the selected cytokines.

Investigation of Dientamoeba fragilis and Blastocystis in patients from Turkey with ulcerative colitis and irritable bowel syndrome: Any relation with genotypes?

Blastocystis sp. and Dientamoeba fragilis are two most common protists worldwide, whose pathogenic potentials are a matter of debate since their discovery. This study aims to investigate the relationship between the activation of ulcerative colitis (UC) and irritable bowel syndrome (IBS) with these protists. A total of 100 patients (35 IBS, 35 active UC, and 30 remittent UC), diagnosed at Hacettepe University Adult Hospital (Ankara, Turkey), were screened for D. fragilis and Blastocystis sp. with microscopic examination using the methods of wet mount, trichrome staining, conventional PCR, nested PCR, real-time PCR and genotyping. Eight patients (4 IBS, 2 active, and 2 remittent UC patients) were found to be D. fragilis positive. 18S rRNA region of the parasite was amplified in four of the patients, whereas cathepsin L-like cysteine peptidase; clan Sc, family S9, serine peptidase; and clan MH, family M20 metallopeptidase in six different patients. All isolates were Genotype 1. Sequence results showed very limited diversity. A total of nine patients (3 IBS, 5 active UC, 1 remittent UC) were found to be positive for Blastocystis sp., all of which were Subtype 3. One active UC and one IBS patient were found to be positive for both parasites. No statistically significant difference was detected between the patient groups in means of parasite detection. D. fragilis was found to be related to older age (p=0,045). In our study, no significant correlation was identified between D. fragilis and Blastocystis sp., and the activation of UC and IBS. More studies are needed on the host-parasite relationship, including the role of gut microbiota, together with transcriptomic and metabolomic assessments to unveil the pathogenicity of both protists.

An Association Between Blastocystis Subtypes and Colorectal Cancer Patients: A Significant Different Profile from Non-cancer Individuals.

PURPOSE: Blastocystis is a common enteric human parasite of non-conclusive pathogenicity which may be determined by subtype (ST) variation. Colorectal cancer (CRC) is considered one of the primary causes of cancer mortality. Blastocystis ST7 has been shown to reduce beneficial intestinal microbiota and may exacerbate CRC. This study assessed the possible association between Blastocystis STs and CRC in comparison to non-cancer patients. MATERIAL AND METHODS: A total of 200 fecal samples were obtained from CRC (100) and non-CRC (100) individuals attending Beni-Suef University Hospital, Egypt. Blastocystis was searched for in all samples using microscopy and culturing. Positive subculture samples were genetically sequenced and subtyped using conventional polymerase chain reaction (PCR). Blastocystis STs were determined by sequencing and a phylogenetic tree was created. Related patient characteristics and tumor stages were analyzed for association with presence of Blastocystis. RESULTS: Blastocystis was identified in 52% and 42% of CRC and non-cancer individuals, respectively. ST1, 2, and 3 were isolated from both cancer and non-cancer individuals; however, for the first time, ST7 was only isolated from CRC stool samples with significant association. Associated patient characteristics were evaluated as predictors. CONCLUSION: Blastocystosis is highly prevalent in CRC patients, predominantly in the latest CRC grades and stages. To the best of our knowledge, this is the first study to report the identification of Blastocystis ST7 in CRC patients. To determine whether certain STs of Blastocystis are associated with CRC would require further research, including the role played by gut microbiota.

The possible link between intestinal parasites and irritable bowel syndrome (IBS) in Diyala Province, Iraq.

The objective of this study was to investigate the prevalence of intestinal parasites and the possible association between irritable bowel syndrome (IBS) and parasitic infections. The study included 100 IBS patients and 100 healthy control subjects. All study subjects filled a structured questionnaire, which covered demographic information and clinical data. Fresh stool samples were collected from patients and control subjects and processed during the same day of collection. Iodine wet mounts and trichrome stained smears prepared from fresh stool and sediment concentrates were microscopically examined for intestinal parasites. Patients attended private gastroenterology clinics and those found to have IBS (45 males and 55 females) were then selected in this study. The healthy subjects (50 males, 50 females) were recruited as controls. In the IBS patients, Blastocystis sp. was detected in 57% and Giardia sp. cysts were observed in 43%. In the control subjects, Blastocystis sp. was detected in 12% and Giardia sp. cysts were observed in 20%. These parasites were found either alone or with other parasites. Only the differences in the presence of Blastocystis (P=0.0001) and Giardia (P=0.0006) between IBS patients and controls were statistically significant. Abdominal pain and blotting were the leading symptoms in IBS patients and controls. Prevalence of Blastocystis and Giardia was higher in IBS patients than in controls. These parasites are likely to have a role in the pathogenesis of IBS. The findings of the study support a possible link between parasitic infections and IBS.

Association between Blastocystis sp. infection and immunocompromised patients: a systematic review and meta-analysis.

The significance of opportunistic infections in immunocompromised patients and the enigmatic pathogenicity of Blastocystis directed us to conduct the first global systematic review and meta-analysis on Blastocystis prevalence, odds ratios (ORs), and subtypes distribution in various immunocompromised patients (HIV/AIDS, cancer and hemodialysis patients, as well as transplant recipients). The systematic searching procedure was done in Web of Science, PubMed, Scopus, and Google Scholar databases for relevant published literature until November 11, 2020. Random-effects model was utilized to calculate the weighted estimates and 95% confidence intervals (95% CIs). The computed pooled prevalence of Blastocystis inferred from 118 papers (128 datasets) on immunocompromised patients was 10.3% (95% CI: 8.7-12.2%), with 16.1% (95% CI: 11.3-22.2%), 12.5% (95% CI: 8.5-18%), 8.4% (95 % CI: 6.6-10.6%), and 6% (95% CI: 2.6-13.3%) for hemodialysis patients, cancer patients, HIV/AIDS patients, and transplant recipients, respectively. Based on 50 case-control studies (54 datasets), the highest ORs were associated with cancer [2.81 (95% CI: 1.24-6.38, P = 0.013)] and hemodialysis patients [2.78 (95% CI: 1.19-6.48, P = 0.018)]. The most frequent subtype being found in immunocompromised patients was ST3 [41.7% (95% CI: 31.4-52.7%)], followed by ST1 [31.7% (95% CI: 23.2-41.8%)] and ST2 [23.1% (95% CI: 14.8-34.1%)]. Also, the weighted frequency of Blastocystis in various subgroups (publication year, WHO regions, geographical distribution, continents, and country income) was analyzed separately. In total, the results of the present meta-analysis highlighted that one's immunodeficiency status is probably associated with an increased Blastocystis infection, underpinning strict preventive measures to be taken.

Prevalence and genetic characteristics of Blastocystis hominis and Cystoisospora belli in HIV/AIDS patients in Guangxi Zhuang Autonomous Region, China.

Blastocystis hominis and Cystoisospora belli are considered to be common opportunistic intestinal protozoa in HIV/AIDS patients. In order to investigate the prevalence and genetic characteristics of B. hominis and C. belli in HIV/AIDS patients, a total of 285 faecal samples were individually collected from HIV/AIDS patients in Guangxi, China. B. hominis and C. belli were investigated by amplifying the barcode region of the SSU rRNA gene and the internal transcribed spacer 1 (ITS-1) region of the rRNA gene, respectively. Chi-square test or Fisher's exact test were conducted to assess the risk factors related to B. hominis and C. belli infection. The prevalence of B. hominis and C. belli was 6.0% (17/285) and 1.1% (3/285) respectively. Four genotypes of B. hominis were detected, with ST3 (n = 8) and ST1 (n = 6) being predominant, followed by ST6 (n = 2) and ST7 (n = 1). Females had a statistically higher prevalence of B. hominis (11.6%) than males (4.2%). The statistical analysis also showed that the prevalence of B. hominis was significantly associated with age group and educational level. Our study provides convincing evidence for the genetic diversity of B. hominis, which indicates its potential zoonotic transmission and is the first report on the molecular characteristics of C. belli in HIV/AIDS patients in China.

Blastocystis spp. y su asociación con otros parásitos intestinales en niños de edad preescolar, estado Sucre, Venezuela / Blastocystis spp. and their association to other intestinal parasites in preschool children from Sucre State, Venezuela

Introducción: Blastocystis spp. es uno de los parásitos intestinales más comunes en el ser humano y su patogenicidad sigue siendo controvertida. Objetivo: Determinar la prevalencia de Blastocystis spp. y su asociación con otros parásitos intestinales a niños en edad preescolar. Métodos: Se procesaron 90 muestras fecales provenientes de niños en edad preescolar. Las técnicas copro-parasitológicas usadas fueron: examen directo con solución salina (0,85 por ciento) y lugol. Se usó la prueba chi cuadrado para demostrar la independencia entre las variables: parasitosis, sexo y edad. Se determinó el índice de afinidad de Fager para establecer las asociaciones entre los principales enteroparásitos identificados. Resultados: Se encontraron 68 niños parasitados, con 75,6 por ciento de prevalencia. No hubo diferencias significativas con respecto a la edad y el sexo (p> 0,05). Los parásitos más comunes fueron: Blastocystis spp. (45,6 por ciento), Endolimax nana (30,9 por ciento), Entamoeba coli (26,5 por ciento), y como único helminto, Enterobius vermicularis (1,5 por ciento). El 42,6 por ciento estuvo monoparasitado y 57,4 por ciento biparasitados. Los índices de afinidad (IAB) y pruebas de "t" efectuadas, señalaron asociación significativa entre Blastocystis spp. y los protozoarios E. nana y E. coli. Conclusiones: Se determina una elevada prevalencia de Blastocystis spp. y especies comensales intestinales, todas indicadoras de contaminación fecal, en que probablemente factores ambientales y socioculturales promueven su transmisión. Este tema debe continuarse y profundizarse por la connotación que ha adquirido este parásito en los debates científicos actuales, tanto en el ámbito nacional como internacional(AU)

Introduction: Blastocystis spp. are among the most common intestinal parasites affecting humans. Their pathogenicity continues to be a topic of debate. Objective: Determine the prevalence of Blastocystis spp. and their association to other intestinal parasites in preschool children. Methods: Analysis was performed of 90 stool samples from preschool children. The coproparasitological techniques used were direct examination with 0.85 percent saline solution and lugol. The chi-square test was used to show the independence between the variables parasitic infection, sex and age. Fager's affinity index was determined to establish associations between the main enteroparasites identified. Results: The study found 68 children infected with parasites, for a 75.6 percent prevalence. There were no significant differences with respect to age and sex (p> 0.05). The most common parasites were Blastocystis spp. (45.6 percent), Endolimax nana (30.9 percent) and Entamoeba coli (26.5 percent). The only helminth found was Enterobius vermicularis (1.5 percent). 42.6 percent of the children were infected with one parasite and 57.4 percent with two. The affinity index (IAB) and t tests performed revealed a significant association between Blastocystis spp. and the protozoa E. nana and E. coli. Conclusions: High prevalence was determined of Blastocystis spp. and intestinal protozoan species, all of which were indicative of fecal contamination. Environmental and sociocultural factors are likely to facilitate their transmission. This topic should continue to be addressed and examined due to the relevance of this parasite in current scientific debate, both nationally and internationally(AU)

Investigation of Isolated Blastocystis Subtypes from Cancer Patients in Turkey.

PURPOSE: It is not clear that Blastocystis remains without damage to the digestive tract or has a pathogenic effect in relation to subtypes in immunocompromised people, such as cancer patients. The present study aimed to investigate the frequency and subtype distribution of Blastocystis in cancer patients who were followed-up and treated in the Oncology clinic of Firat University Hospital and to determine the clinical signs of infected sufferers. METHODS: 201 patients aged ≥ 18 with a diagnosis of cancer were enrolled in this cross-sectional study. Patients' stool samples were examined between September 2017 and August 2019 by native-Lugol, trichrome staining. Microscopy-positive stool samples were subjected to DNA isolation and subtyped by Sequence Tagged Site (STS)-PCR analysis. The symptoms and demographic characteristics of the patients were also evaluated. RESULTS: Totally, 29 (14.4%) samples were positive for Blastocystis after all methods. 15 (51.7%) out of 29 samples were successfully subtyped by the sequenced-tagged site(STS)-PCR, while 14 (48.3%) could not be typed. Three subtypes of Blastocystis were detected: ST3 (40%), ST2 (33%), ST1 (20%), and one mixed infections with ST1/ST2 (6%). There was no statistically significant difference in terms of clinical findings and demographic characteristics. CONCLUSION: The outcomes of our study promote the idea that Blastocystis could be an asymptomatic and harmless commensal organism. However, more comprehensive molecular and clinical studies are needed to fully determine the pathogenicity and epidemiology of Blastocystis in cancer patients.

Comparison of diagnostic methods (wet mount, trichrome staining, formol-ether, PCR, and xenic in vitro culture) for the detection of Blastocystis in stool samples in Urmia educational hospitals, the Northwest of Iran.

Blastocystis spp. is known as a common intestinal protozoan parasite in human and animals. The parasite has a worldwide distribution and is frequently detected in faecal samples in clinical parasitology laboratories. The goal of the study was to compare the sensitivity and specificity of formol-ether technique (FECT), trichrome staining, xenic in vitro culture (XIVC), microscopy of faecal smears, and polymerase chain reaction (PCR) methods for detecting Blastocystis spp. in human stool samples. The prevalence of the parasite in the stool samples referred to educational hospitals was also determined. A total of 575 cases were assessed to detect the parasite. After collecting from patients referring to Urmia educational hospitals, the samples were examined by microscopy of faecal smears, trichrome staining, FECT, XIVC using Jones' medium, and PCR, to evaluate the presence of Blastocystis spp. Microscopy of faecal smears, trichrome staining, FECT, and PCR technique detected 94, 100, 96, and 44 positive cases, with the sensitivity of 71.3%, 74.4%, 74.4%, and 80.4% and the specificity of 99.6%, 99.1%, 100%, and 93.1%, respectively. XIVC method identified the highest number of positive cases (129 cases) among the other methods. Our findings indicates that XIVC technique is more sensitive method for the detection of Blastocystis spp. in human stool, as compared to direct smear, trichrome staining, FECT, and PCR methods.

Current status of research regarding Blastocystis sp, an enigmatic protist, in Brazil

The present study aimed to evaluate the occurrence of Blastocystis sp. in Brazilian studies over a period of years (2000-2020), as well as point out relevant aspects of this enigmatic organism. We performed a literature search using six sources of international databases. The data were divided into diagnostic by parasitological and molecular techniques, and relevant aspects. After applying the inclusion and exclusion criteria, 52 studies were included in the final analysis. The occurrence of Blastocystis sp. in Brazil ranged from 0.5% to 86.6%, as determined using parasitological techniques. The highest occurrence was in the North (27.3%) and the lowest, in the Midwest region (13.4%). In Brazil, most studies have employed molecular techniques and are concentrated in the Southeast region. The Blastocystis sp. subtype ST3 had the highest average positivity, followed by ST1 and ST2. These findings represent a panorama that reflects the reality of Brazil; thus, we believe that the effectiveness of parasitological diagnosis should be considered with regard to making an appropriate choice of technique for detecting Blastocystis sp. Additionally, we emphasize the importance of further studies in the context of molecular epidemiology with regard to this genus. Blastocystis sp. is not well understood yet, and very little information regarding this genus is available; hence, further research regarding this genus is urgently needed.

Epidemiology of Blastocystis infection from 1990 to 2019 in China.

BACKGROUND: Blastocystis is ubiquitous presence in animals and humans worldwide and has a high level genetic diversity. The aim of this study was to conduct a summary of Blastocystis prevalence, subtypes (STs) in humans and animals in China and depict their distribution. METHODS: We searched for the articles related to epidemiology of Blastocystis in humans and animals throughout China which published from January 1, 1990, to July 31, 2019 in the following databases: PubMed, China National Knowledge Infrastructure (CNKI) and Wanfang database. The keywords were Blastocystis and one of the following ones: STs, subtypes, distribution, epidemiology, prevalence, infection, molecular, geographic, intestinal parasites, genetic diversity and characterization. RESULTS: In recent years, various molecular epidemiological studies have been carried out in some provinces/regions of China to identify subtypes of Blastocystis. Infants and young children, school students, hospitalized diarrhea patients, HIV/AIDS patients, tuberculosis patients, and cancer patients as respondents had been included. ST1-ST7 and ST12 were the main subtypes in Chinese population. Moreover, surveys of Blastocystis infection in animal were also conducted in some provinces of China. A variety of animals were investigated including pigs, cattle, sheep, yak, giant panda, and crested ibis (Nipponia nippon) with the main subtypes of ST1-ST8, ST10, ST12-ST14. CONCLUSIONS: In recent years, some provinces/regions in China have conducted various molecular epidemiological studies to identify the Blastocystis subtypes. It is important to focus on new subtypes and mixed subtypes of infection, while increasing data on ribosomal alleles. We encourage the scientific community to start research on humans and surrounding animals (including domestic and wild animals) to better understand the possibility of Blastocystis transmission between humans and animals. We call for action among researchers studying intestinal parasitic diseases (Blastocystis), start drawing the subtype of Blastocystis and increase the subtype related to its clinical symptoms.

Cockroach as a Vector of Blastocystis sp. is Risk for Golden Monkeys in Zoo.

Blastocystis sp. is a kind of protozoa living in the intestinal tract of human and animals, which will cause intestinal diseases such as diarrhea, abdominal distension and vomiting. This paper was aimed to understand the infection of Blastocystis sp. In golden monkeys and the transmission path in North China. Thirty-seven feces samples from golden monkeys and 116 cockroach samples from Shijiazhuang Zoo were collected from July to October 2019 for PCR analysis of Blastocystis sp. Genetic diversity analysis was further conducted on the samples with positive PCR results. The results showed that the infection rate was 48.7% (18/37) in golden monkeys and 82.8% (96/116) in cockroaches, respectively. The genetic evolution analysis based on small subunit ribosomal RNA demonstrated that three subtypes (ST) of Blastocystis sp. including ST1, ST2, and ST3 existed in the intestinal tract of golden monkeys, while only ST2 was detected in the intestinal tract of cockroaches. This paper may provide supports for the quarantine and control of Blastocystis sp. for the zoo in Northern China.

Molecular identification and subtypes distribution of Blastocystis sp. isolated from children and adolescent with cancer in Iran: evaluation of possible risk factors and clinical features.

PURPOSE: This study aimed to determine the molecular characterization and subtype distribution of Blastocystis sp. isolated from cancer children and adolescents in Shiraz, Fars province, southwestern Iran. METHODS: Overall, 200 fecal samples obtained from cancer children and adolescents under 18 years old (107 males and 93 females) and checked by microscopy, culture, and molecular methods (PCR). Possible etiological factors and clinical characteristics of Blastocystis infection were also evaluated and compared between Blastocystis infected and non-infected patients. RESULTS: Thirteen of 200 (6.5%) stool samples were positive for Blastocystis by microscopy. While 21 of 200 (10.5%) were positive by culture, and 24 of 200 (12%) were positive by PCR. Out of 24 positive samples tested by PCR and sequencing, ST3 was reported as the most common subtype (nine samples, 37.5%), followed by ST2 (eight samples, 33.3%), ST1 (five samples, 20.9%), and ST7 (two samples, 8.3%). The prevalence of Blastocystis infection in males was significantly higher than females (p = 0.024). Also, Blastocystis was more prevalent in patients who had received at least eight chemotherapy cycles than fewer (p = 0.002). However, no associations were found between Blastocystis-positive rate and age, residence, type of cancers, or contact with animals. Also, there was no significant difference between frequency of Blastocystis subtypes in symptomatic and asymptomatic cancer patients. CONCLUSIONS: Various controlled epidemiologic and topographic studies need to confirm or reject these possible associations with Blastocystis infection. The data from this study are an invaluable addition to the growing body of research studies on Blastocystis infection in cancer patients.