Permanent and transient congenital hypothyroidism in Korea: analysis of patients in a single center

Results Of the 610 patients diagnosed primarily with CH; 554 (89.1%) patients were diagnosed to have permanent CH, and 66 (10.8%) patients were diagnosed to have transient CH. The median TSH levels before treatment were significantly higher in patients with permanent CH than transient CH (median 58.1:24.1 μIU/mL). Male to female ratio was 1:1.2 (35:31) in transient CH. Of the 66 children diagnosed with transient CH, children discontinued levothyroxine replacement therapy at the age of 25.1±13.2 months. These patients received relatively low dose hormone replacement (initial and at the time of trial of discontinuation).