Endocrine Unit, Department of Medicine and Surgery, Ospedale Di Circolo, ASST Dei Sette Laghi, University of Insubria, Viale Borri, 57, Varese, Italy.
Gastroenterology and Gastrointestinal Endoscopic Unit, Department of Specialistic Medicine, ASST Dei Sette Laghi, Varese, Italy.
J Endocrinol Invest. 2020 Jul;43(7):885-899. doi: 10.1007/s40618-020-01208-6. Epub 2020 Mar 12.
A complex relationship exists between thyroid and liver in health and disease. Liver plays an essential physiological role in thyroid hormone activation and inactivation, transport, and metabolism. Conversely, thyroid hormones affect activities of hepatocytes and hepatic metabolism. Serum liver enzyme abnormalities observed in hypothyroidism may be related to impaired lipid metabolism, hepatic steatosis or hypothyroidism-induced myopathy. Severe hypothyroidism may have biochemical and clinical features, such as hyperammonemia and ascites, mimicking those of liver failure. Liver function tests are frequently abnormal also in hyperthyroidism, due to oxidative stress, cholestasis, or enhanced osteoblastic activity. Antithyroid drug-associated hepatotoxicity is a rare event, likely related mainly to an idiosyncratic mechanism, ranging from a mild hepatocellular damage to liver failure. Propylthiouracil-induced liver damage is usually more severe than that caused by methimazole. On the other hand, thyroid abnormalities can be found in liver diseases, such as chronic hepatitis C, liver cirrhosis, hepatocellular carcinoma, and cholangiocarcinoma. In particular, autoimmune thyroid diseases are frequently found in patients with hepatitis C virus infection. These patients, especially if thyroid autoimmunity preexists, are at risk of hypothyroidism or, less frequently, thyrotoxicosis, during and after treatment with interpheron-alpha alone or in combination with ribavirin, commonly used before the introduction of new antiviral drugs. The present review summarizes both liver abnormalities related to thyroid disorders and their treatment, and thyroid abnormalities related to liver diseases and their treatment.
甲状腺与肝脏在健康和疾病中存在着复杂的关系。肝脏在甲状腺激素的激活和失活、转运和代谢中发挥着重要的生理作用。相反，甲状腺激素影响肝细胞的活动和肝脏的代谢。甲状腺功能减退症中观察到的血清肝酶异常可能与脂质代谢受损、肝脂肪变性或甲状腺功能减退症引起的肌病有关。严重的甲状腺功能减退症可能具有生化和临床特征，如高氨血症和腹水，类似于肝功能衰竭。由于氧化应激、胆汁淤积或成骨细胞活性增强，甲状腺功能亢进症也经常出现肝功能试验异常。抗甲状腺药物相关性肝毒性是一种罕见的事件，可能主要与一种特发性机制有关，从轻度肝细胞损伤到肝功能衰竭不等。丙硫氧嘧啶引起的肝损伤通常比甲巯咪唑引起的更严重。另一方面，肝脏疾病可导致甲状腺异常，如丙型肝炎、肝硬化、肝癌和胆管癌。特别是，丙型肝炎病毒感染患者常发现自身免疫性甲状腺疾病。这些患者，尤其是如果甲状腺自身免疫存在，在单独使用干扰素-α或与利巴韦林联合治疗期间和之后发生甲状腺功能减退症或甲状腺功能亢进症的风险增加，干扰素-α和利巴韦林是在新的抗病毒药物问世之前常用的药物。本综述总结了与甲状腺疾病相关的肝脏异常及其治疗，以及与肝脏疾病相关的甲状腺异常及其治疗。
