Chronic urticaria associated with Blastocystis hominis infection.

Urticaria is a skin rash with several etiologic factors, including infectious agents. Blastocystis hominis is an intestinal protozoan parasite that has been linked to urticaria and skin lesions. The aim of this work was to investigate the association between B. hominis infection and chronic urticaria. In a case-control study, stool samples were obtained from 94 patients with chronic urticaria as case group and 285 healthy individuals as control group. Urticaria activity score 7 (UAS7) was used to score the severity of urticaria, classified as mild, moderate and intense. All stool samples underwent routine stool examinations, as well as polymerase chain reaction (PCR) for the detection of B. hominis. Molecular detection was carried out using the small subunit ribosomal RNA (SSU-rRNA) gene and the parasite subtypes were determined by sequencing. The rate of B. hominis infection was 21.3% (20 out of 94) and 17.2% (49 out of 285) between the case and control groups, respectively (p = 0.463). Three subtypes of B. hominis, including ST-1, ST-2 and ST-3, were detected in the case and control groups (ST-1 = 30% vs. 8.3%, ST-2 = 40% vs. 25% and ST-3 = 30% vs. 66.6% in the case and control group, respectively), which was statistically significant (p = 0.00001). However, no statistical differences were found between the severity of the urticaria and the B. hominis subtypes (p = 0.533). This study revealed a higher prevalence (but not significant) of B. hominis infection among patients with urticaria than healthy individuals. However, the results did not find a significant association between the subtypes of B. hominis and the severity of urticaria.

Urticaria and the gut.

PURPOSE OF REVIEW: To review recent evidence on the association of urticaria and the gut diseases, focusing on the roles of chronic inflammation with or without Helicobacter pylori (H. Pylori) infection. RECENT FINDINGS: The connection between the gut and urticaria has been discussed for a long time. Some publications have shown that H. pylori can induce chronic spontaneous urticaria (CSU). Recently, it was reported that upper gastrointestinal inflammatory disorders can cause CSU and trigger exacerbations independently of H. pylori. SUMMARY: Gastritis and especially H. pylori-induced gastritis has been implicated as potential trigger of CSU. Chronic parasite infection and inflammation of the gut are relevant comorbidities and also potential inducing factors for the development of urticaria.

Prevalence and Molecular Subtyping of Blastocystis from Patients with Irritable Bowel Syndrome, Inflammatory Bowel Disease and Chronic Urticaria in Iran.

BACKGROUND: Blastocystis is a parasite that colonizes in the human intestine. Its clinical features include diarrhea, abdominal pain, or urticarial and irritable bowel syndrome (IBS). Spite of being significant genetic diversity and numerous subtypes within the genus there were no associations between its subtypes and symptomatology. MATERIALS AND METHODS: Aim of this project was subtyping of the protozoa in 184 Iranian people with history of IBS/IBD (n = 74) or chronic urticaria (n = 59) and individuals referred to general clinic (n = 51). Microscopic and molecular examinations used for identifying and subtyping of Blastocystis. RESULTS: Overall, frequency of the parasite was 24.46% while, 29.41% of people who referred to general clinic, 20.27%, and 25.42% of IBS/IBD and urticarial cases were infected, respectively. Subtyping result showed that 28.89% of all people were infected with Blastocystis sp. while the prevalence of ST3, ST2 and ST1 were 22.22%, 22.22%, and 17.78%, respectively. Blastocystis sp., was identified in most IBS/IBD cases (46.7%) followed with ST2 and ST3 (13.3 and 13.3, respectively). Whereas, in chronic urticaria group ST2(33.3%) was the major subtype and most individuals in control group were infected with ST3 (33.3%). Pearson's Chi Square test showed no significant differences between the parasite or subtype prevalence and diseases (p > 0.05). CONCLUSION: Given significant factors have effect on clinical signs including host or parasite genetics, microbiota, as well as environmental factors, it seems that further studies are needed to find out different markers of host susceptibility to diverse parasite genotypes in patients with irritable bowel syndrome or urticaria.

Evaluation of intestinal parasites in patients with chronic spontaneous urticaria in a territory hospital in Turkey.

INTRODUCTION: Chronic spontaneous urticaria (CSU) which develops without a known stimulation is defined as the occurrence of spontaneous wheals, angioedema or both for longer than six weeks. Infections, autoimmunity, food intolerance and internal parasitic infections are supposed to be underlying causes of CSU. The aim of this study was to evaluate the intestinal parasites in children and adult patients diagnosed as CSU, to determine the frequency of parasites in chronic urticaria, and to compare these patients with healthy demographic control groups. METHODOLOGY: Seventy six children and 38 adult patients with CSU were examined in terms of parasitic infections. The patients whom parasites were detected received anti-parasitic therapy and the improvements in CSU symptoms were evaluated. Stool samples were examined with direct microscopic examination (native-lugol), stool concentration and trichrome staining methods. RESULTS: In pediatric patient group, 18.4% (n = 14) of the stool samples were positive for Blastocystis sp., 2.6% (n = 2), Dientamoeba fragilis and 1.3% (n = 1), Giardia duodenalis. In adult patient group, Blastocystis sp. was detected in 18.4% (n = 7) of the stool samples. Anti-parasitic therapy yielded substantial improvement in urticaria symptoms in 57.1% of pediatric and 60.0% of adult patients. CONCLUSIONS: Blastocystis sp. and D. fragilis may play a role in chronic urticaria which seriously disrupts the patient's quality of life. Parasitic infections should not be neglected in patients with cutaneous manifestations.