Clinical feature and genetic analysis of Gitelman's syndrome accompanied by autoimmune thyroid disease

Objective To explore the relationship between Gitelman's syndrome (GS) and autoimmune thyroid disease.Methods Serum and urinary electrolytes,plasma renin activity,aldosterone,angiotensin Ⅱ,and thyroid function in 9 patients with GS were determined.26 exons encoding sodium chloride cotransporter (NCCT) were amplified by PCR,completely sequenced by the direct sequencing method,and analyzed for the mutations of NCCT gene in those patients.Finally,restriction fragment length polymorphism was performed in one patient and her family members.Results Those patients presented laboratory findings typical of GS,such as hypokalemia,hypomagnesemia,hypocalciuria,and all were normotensive or hypotensive.Angiotensin II level was high in all nine GS patients.Interestingly,three of these patients were accompanied by autoimmune thyroid disease.Six NCCT gene mutations were identified.However,two patients did not show any mutation.No thyroid disease-related gene mutation in NCCT was found.Conclusion Gene detection is a useful tool for the diagnosis of GS.Patients with GS seem to be prone to accompaniment of autoimmune thyroid disease. Key words: Gitelman's syndrome;  Genetics ;  Na-Cl cotransporter ;  Thyroid disease ;  Autoimmunity