El Shabrawy Reham M, Atta Amal H, Rashad Nearmeen M
Department of Medical Microbiology & Immunology, Faculty of Medicine, Zagazig, Zagazig, University Egypt.
Department of Internal Medicine, Faculty of Medicine, Zagazig, Zagazig, University Egypt.
Egypt J Immunol. 2016 Jan;23(1):77-86.
Thyroid peroxidase (TPO) is the key enzyme in the biosynthesis of thyroid hormones T3 and T4. Autoimmune thyroiditis is a common disorder affecting 10% of population worldwide. A key feature of autoimmune thyroiditis is the presence of anti TPO antibodies, and some mutation of the TPO gene. Association between autoimmune thyroiditis and other autoimmune disorders has been reported but little is known about association with allergic diseases. In this study, we aimed to evaluate frequency of hidden autoimmune thyroiditis among allergic patient and examine possible relationship between anti-TPO levels and polymorphism at the TPO gene A2173/C exon 12 and different types of allergens. The study included 50 adult Egyptian patients with allergic rhinitis and /or bronchial asthma and 50 controls. For each subject, thyroid stimulating hormone (TSH), thyroxin 4 (T4) and Triiodothyronine (T3) hormones were measured. Anti-thyroid peroxidase (anti-TPO) level was detected by ELISA; and TPO gene polymorphism 2173A>C exon 12 was analyzed using restriction fragment length polymorphism (RFLP). Skin prick test was done to assess allergic response in patients. Serum levels of T3, T4 and TSH did not show any statistical significant difference between patients and groups. However, mean serum anti-TPO level was statistically higher in patients than controls, and correlated positively with body mass index, age, diastolic blood pressure, suggesting higher prevalence of hidden autoimmune thyroiditis in allergic patients than in control group. 2173A>C Genotyping revealed that the frequency of C allele is increased in the patient group. C allele represents a risk factor with odds ratio of 2.37 (1.035-5.44) and a significant P value <0.05. It is concluded that TPO 2173A>C polymorphism may be considered as a risk factor for developing autoimmune thyroiditis in patients with allergic rhinitis and asthma and that these patients should regularly be checked for hidden thyroiditis.
甲状腺过氧化物酶（TPO）是甲状腺激素T3和T4生物合成中的关键酶。自身免疫性甲状腺炎是一种常见疾病，全球10%的人口受其影响。自身免疫性甲状腺炎的一个关键特征是存在抗TPO抗体以及TPO基因的一些突变。已有报道自身免疫性甲状腺炎与其他自身免疫性疾病之间存在关联，但关于其与过敏性疾病的关联却知之甚少。在本研究中，我们旨在评估过敏患者中隐匿性自身免疫性甲状腺炎的发生率，并研究抗TPO水平与TPO基因第12外显子A2173/C多态性以及不同类型过敏原之间的可能关系。该研究纳入了50名患有过敏性鼻炎和/或支气管哮喘的成年埃及患者以及50名对照。对每个受试者测量促甲状腺激素（TSH）、甲状腺素4（T4）和三碘甲状腺原氨酸（T3）激素。通过酶联免疫吸附测定（ELISA）检测抗甲状腺过氧化物酶（抗TPO）水平；并使用限制性片段长度多态性（RFLP）分析TPO基因第12外显子2173A>C多态性。进行皮肤点刺试验以评估患者的过敏反应。患者组和对照组之间的血清T3、T4和TSH水平未显示出任何统计学上的显著差异。然而，患者的血清抗TPO平均水平在统计学上高于对照组，且与体重指数、年龄、舒张压呈正相关，表明过敏患者中隐匿性自身免疫性甲状腺炎的患病率高于对照组。2173A>C基因分型显示患者组中C等位基因的频率增加。C等位基因代表一个风险因素，优势比为2.37（1.035 - 5.44），且P值显著<0.05。得出的结论是，TPO 2173A>C多态性可能被视为过敏性鼻炎和哮喘患者发生自身免疫性甲状腺炎的一个风险因素，并且这些患者应定期检查是否存在隐匿性甲状腺炎。
