Introduction and objective:
Intestinal parasitoses are important causes of morbidity and mortality, especially in immunocompromised individuals. In patients with chronic renal insufficiency (CRI), the accumulation of non-excreted metabolites leads to uraemia, which induces a state of immunodeficiency, increasing the incidence of infections. The aim of the study was molecular screening for enteric protozoa in patients with chronic renal insufficiency.

Material and methods:
A total of 53 samples were collected in January 2023 from patients undergoing dialysis at Logman Ltd. Nephrodialysis Centre in Košice, Slovakia. Samples were examined by polymerase chain reaction (PCR) for the presence of Cryptosporidium parvum / Cryptosporidium hominis, Giardia intestinalis, Microsporidia spp., and Blastocystis sp.

From the 53 samples, the only pathogen identified by PCR was Blastocystis sp., in 13 patients (24.5 %). Sequence analyses confirmed that the most prevalent subtype (ST) among patients was ST 3 (n=9, 69.2%), followed by ST 1 (n=3, 23.1%) and ST 2 (n=1, 7.7%).

Molecular methods for the detection of microscopic enteric parasites are not used as a first-line diagnostic method in Slovakia. In immunocompromised patients, diarrhoea can be caused not only by a chronic disease or therapy but can also be a result of an ongoing underdiagnosed infection. Early diagnosis leads to targeted therapy and subsequent partial improvement of the quality of life. This study also shows the first insights into Blastocystis sp. subtype distribution in humans in Slovakia.

The authors express their thanks for funding donated by the Scientific Grant Agency VEGA – VEGA MŠVVaŠ a SAV (Grant No. VEGA 1/0359/21).
Al-Yousofi A, Yan Y, Al-Mekhlafi AM, et al. Prevalence of intestinal parasites among immunocompromised patients, children, and adults in Sana’a, Yemen. J Trop Med. 2022;8:2022:5976640.
Gulhan B, Aydin M, Demirkazik M, et al. Subtype distribution and molecular characterization of Blastocystis from hemodialysis patients in Turkey. J Infect Dev Ctries. 2020;14(12):1448–54.
Seatamanoch N, Kongdachalert S, Sunantaraporn S, et al. Microsporidia, a highly adaptive organism and its host expansion to humans. Front Cell Infect Microbiol. 2022;12:924007.
Kaya F, Inkaya AÇ, Maçin S, et al. Refractory giardiasis in an immunosuppressed patient in Turkey. J Infect Dev Ctries. 2018;12(3):204–7.
Kulik R, Falavigna D, Nishi L, et al. Blastocystis sp. and other intestinal parasites in hemodialysis patients. Braz J Infect Dis. 2008;12(4):338–41.
Higuera A, Herrera G, Jimenez P, et al. Identification of multiple Blastocystis subtypes in domestic animals from Colombia using amplicon-based next generation sequencing. Front Vet Sci. 2021;8:732129.
Nemati S, Zali MR, Johnson P, et al. Molecular prevalence and subtype distribution of Blastocystis sp. in Asia and in Australia. J Water Health. 2021;19:687–704.
Šloufová M, Lhotská Z, Jirků M, et al. Comparison of molecular diagnostic approaches for the detection and differentiation of the intestinal protist Blastocystis sp. in humans. Parasite. 2022;29:30.
El Safadi D, Gaayeb L, Meloni D, et al. Children of Senegal River Basin show the highest prevalence of Blastocystis sp. ever observed worldwide 2014. BMC Infect Dis. 2014; 14(1):164.
Esteghamati A, Khanaliha K, Bokharaei-Salim F, et al. Prevalence of intestinal parasitic infection in cancer, organ transplant and primary immunodeficiency patients in Tehran, Iran. Asian Pac J Cancer Prev. 2019;20(2):495–501.].
Fontanelli Sulekova L, Gabrielli S, Furzi F, et al. Molecular characterization of Blastocystis subtypes in HIV-positive patients and evaluation of risk factors for colonization. BMC Infect Dis. 2019;19(1):876.
Wawrzyniak I, Poirier P, Viscogliosi E, et al. Blastocystis, an unrecognized parasite: an overview of pathogenesis and diagnosis. Ther Adv Infect Dis. 2013;1(5):167–78.
Tan KSW. New insights on classification, identification, and clinical relevance of Blastocystis spp. Clin Microbiol Rev. 2008;21(4):639–65.
Betts EL, Gentekaki E, Tsaousis AD. Exploring micro-eukaryotic diversity in the gut: co-occurrence of Blastocystis subtypes and other protists in zoo animals. Front Microbiol. 2020;11:288.
Danišová O, Valenčáková A, Stanko M, et al. Rodents as a reservoir of infection caused by multiple zoonotic species/genotypes of C. parvum, C. hominis, C. suis, C. scrofarum, and the first evidence of C. muskrat genotypes I and II of rodents in Europe. Acta Trop. 2017;172:29–35.
Iqbal A, Lim YAL, Surin J, et al. High Diversity of Cryptosporidium Subgenotypes Identified in Malaysian HIV/AIDS Individuals Targeting gp60 Gene. PLoS One. 2012;7(2):e31139.
Sulaiman IM, Fayer R, Bern C, et al. Triosephosphate isomerase gene characterization and potential zoonotic transmission of Giardia duodenalis. Emerg Infect Dis. 2003;9(11):1444–52.
Katzwinkel-Wladarsch S, Lieb M, Heise W, et al. Direct amplification and species determination of microsporidian DNA from stool specimens. Trop Med Int Health. 1996;1(3):373–8.
Santín M, Gómez-Munoz MT, Solano-Aguilar G, et al. Development of a new PCR protocol to detect and subtype Blastocystis spp. from humans and animals. Parasitol Res. 2011;109(1):205–12.
Karadag G, Tamer G, Dervisoglu E. Investigation of intestinal parasites in dialysis patients. Saudi Med J. 2013;34(7):714–8.
Meijers RWJ, Litjens NHR, de Wit EA, et al. Uremia causes premature ageing of the T cell compartment in end-stage renal disease patients. Immun Ageing. 2012;9(1):19.
Gama NA, Leite Adami Y, Lugon R. Assessment of Blastocystis spp. infection in hemodialysis patients in two centers of the metropolitan area of Rio de Janeiro. J Kidney Treat Diagn. 2018;1:49–52.
Gil FF, Barros MJ, Macedo NA, et al. Prevalence of intestinal parasitism and associated symptomatology among hemodialysis patients. Rev Inst Med Trop Sao Paulo. 2013;55(2):69–74.
Fallah Omrani V, Fallahi S, Rostami A, et al. Prevalence of intestinal parasite infections and associated clinical symptoms among patients with end-stage renal disease undergoing hemodialysis. Infection. 2015;43(5):537–44.
Hawash YA, Dorgham LS, Amir EAM, et al. Prevalence of intestinal protozoa among Saudi patients with chronic renal failure: A Case-Control Study. J Trop Med. 2015;2015: 563478.
Barazesh A, Fouladvand M, Tahmasebi R, et al. The prevalence of intestinal parasites in hemodialysis patients in Bushehr, Iran. Hemodial Int. 2015;19(3):447–51.
Rasti S, Hassanzadeh M, Hooshyar H, et al. Intestinal parasitic infections in different groups of immunocompromised patients in Kashan and Qom cities, central Iran. Scand J Gastroenterol. 2017;52(6–7):738–741. https://doi:10.1080/00365521.2....
Stensvold CR, Clark CG. Current status of Blastocystis: A personal view. Parasitol Int. 2016;65(6 Pt B):763–71.
Silva M do RA, Melo GB, Malta FM, et al. Subtypes of Blastocystis sp. isolated in fecal samples from transplant candidates in Sao Paulo, Brazil. Parasite Epidemiol Control. 2020;8:e00128.
Dogruman-Al F, Kustimur S, Yoshikawa H, et al. Blastocystis subtypes in irritable bowel syndrome and inflammatory bowel disease in Ankara, Turkey. Mem Inst Oswaldo Cruz. 2009;104(5):724–7.
Dagci H, Kurt Ö, Mandiracioglu A, et al. Epidemiological and diagnostic features of Blastocystis infection in symptomatic patients in Izmir province, Turkey. Iran J Parasitol. 2014;9(4):519–29.
Dogruman-Al F, Dagci H, Yoshikawa H, et al. A possible link between subtype 2 and asymptomatic infections of Blastocystis hominis. Parasitol Res. 2008;103(3):685–9.
Wong KHS, Ng GC, Lin RTP, et al. Predominance of subtype 3 among Blastocystis isolates from a major hospital in Singapore. Parasitol Res. 2008;102(4):663–70.
Stensvold CR, Alfellani MA, Norskov-Lauritsen S, et al. Subtype distribution of Blastocystis isolates from synanthropic and zoo animals and identification of a new subtype. Int J Parasitol. 2009;39(4):473–9.
Stensvold CR, Clark CG. Pre-empting Pandora’s Box: Blastocystis Subtypes Revisited. Trends Parasitol. 2020;36(3):229–32.
Ramírez JD, Sánchez A, Hernández C, et al. Geographic distribution of human Blastocystis subtypes in South America. Infect Genet Evol. 2016;41:32–5.
Mattiucci S, Crisafi B, Gabrielli S, et al. Molecular epidemiology and genetic diversity of Blastocystis infection in humans in Italy. Epidemiol Infect. 2016;144(3):635–46.
Khaled S, Gantois N, Ly AT, et al. Prevalence and subtype distribution of Blastocystis sp. in Senegalese school children. Microorganisms. 2020;8(9):1408.
Aynur ZE, Güçlü Ö, Yildiz I, et al. Molecular characterization of Blastocystis in cattle in Turkey. Parasitol Res. 2019;118(3):1055–9.
Sarzhanov F, Dogruman-Al F, Santin M, et al. Investigation of neglected protists Blastocystis sp. and Dientamoeba fragilis in immunocompetent and immunodeficient diarrheal patients using both conventional and molecular methods. PLoS Negl Trop Dis. 2021;15(10):e0009779.
Danišová O, Valenčáková A, Kandráčová P, et al. First report of Blastocystis spp. subtypes in ZOO animals in Slovakia, Central Europe. Ann Agric Environ Med. 2022;29(1):149–51.
Danišová O, Valenčáková A. First detection of Blastocystis sp. in pigs in Slovakia and in Europe. Parasitol Int. 2021;81:102235.
Valenčáková A, Sučik M, Danišová O, et al. Detection of Blastocystis spp., Cryptosporidium spp. and Encephalitozoon spp. among wild animals from Eastern Slovakia. Acta Vet Hung 2022;70:220–5.
Journals System - logo
Scroll to top