Study of Blastocystis hominis isolates in urticaria: a case–control study

Abstract

Blastocystis hominis is a common intestinal parasite, with a prevalence in developing countries of up to 50%. The aim of this study was to investigate the association of this parasite with urticaria by determining the genotypic isotypes in the Egyptian population. In total, 54 patients with urticaria and 50 controls were enrolled in the study. Stool samples were examined and assessed by PCR. The parasite was detected in a significantly higher number (P < 0.001) of the patient group than the control group. There was no significant difference between the patients with acute and those with chronic urticaria (P = 0.2). The amoeboid form was found in 60.6% of Blastocystis-positive patients with urticaria, but in none of the healthy controls. Subtype 3 was the only isolate found in both the patient and control groups. We recommend treatment for Blastocystis-positive patients with urticaria in developing countries. The prevalence is much lower (around 10%) in developed countries, where treatment should only be considered in the absence of other possible causes of urticaria.

Eradication of Blastocystis hominis prevents the development of symptomatic Hashimoto’s thyroiditis: a case report

“…However, a number of case reports recently showed that Blastocystis hominis infection is associated with chronic urticaria [5][6][7]. The study of Zuel-Fakkar et al reported that Blastocystis hominis was found in 60.6% of patients with urticaria, whereas no parasite was isolated in healthy controls [8]. In general, urticaria is a very common skin disorder that can have immune, non-immune or idiopathic causes [9].…”

Blastocystis, an unrecognized parasite: an overview of pathogenesis and diagnosis

“…In addition to aspecific gastrointestinal symptoms, studies associated the parasite with cutaneous disorders and chronic or acute urticaria [Vogelberg et al 2010;Hameed et al 2011;Zuel-Fakkar et al 2011;Verma and Delfanian, 2013]. These diseases were correlated with the presence of Blastocystis sp.…”

“…These diseases were correlated with the presence of Blastocystis sp. belonging to the ST2 [Vogelberg et al 2010] or ST3 [Zuel-Fakkar et al 2011] in the patient stools. An association was also found between urticaria and amoeboid forms of a ST3 isolate [Katsarou-Katsari et al 2008].…”

Enteric Protozoa in the Developed World: a Public Health Perspective

“…Metronidazole is the suggested drug of choice, although failures of this drug in eradicating the organism are common (275,407,409). Cotrimoxazole, nitazoxanide, and a combination of paromomycin and metronidazole have also been used (222,485). A recent study found extensive differences in drug sensitivities among two clinically important zoonotic subtypes (subtypes 4 and 7) and identified four new potential therapeutic options against Blastocystis spp., namely, mefloquine, cotrimoxazole (trimethoprim-sulfamethoxazole) (1:2), ornidazole, and furazolidone; the study also confirmed the antiprotozoal activities of 10 compounds already reported to be effective against Blastocystis spp.…”