Akademik Veri Yönetim Sistemi
ACTA PARASITOLOGICA, cilt.70, sa.208, ss.1-19, 2025 (SCI-Expanded, Scopus)
Purpose
Blastocystis spp. is the most commonly identified protozoan in humans, yet its clinical significance and pathogenicity remain controversial. While often asymptomatic, it has been associated with gastrointestinal symptoms and urticaria. Metronidazole is the most frequently used first-line treatment; however, increasing reports of resistance and treatment failure have led to growing interest in alternative therapeutic options.
Methods
In this systematic review, we searched the Web of Science, Scopus, and PubMed databases using relevant keywords in article titles to identify studies related to the treatment of Blastocystis spp.
Results A total of 195 records were retrieved. After removing duplicates and applying inclusion and exclusion criteria, 39 studies were deemed eligible. Data extracted included author, publication year, country, number of participants or samples, diagnostic method, subtype, treatment agent, dosage, intervention details, and clinical and parasitological outcomes. Of the included studies, 17 were human studies (14 clinical trials and 3 case reports), and 22 were in vitro or animal studies.
Conclusion Our findings suggest that metronidazole may be inappropriate as a first-line treatment, as it can increase the number of viable parasites and promote their transformation into apoptosis-resistant granular or more pathogenic amoeboid forms. Alternative agents—such as ronidazole, satranidazole, and C17 (2-position 5-nitroimidazoles), as well as ornidazole, secnidazole, and tinidazole (1-position 5-nitroimidazoles with different side chains compared with metronidazole)—show potential efficacy. Trimethoprim-sulfamethoxazole and nitazoxanide have also demonstrated promising results. Further studies, particularly subtype-specific and human clinical trials, are needed to assess the safety and efficacy of these alternative agents against Blastocystis spp.