GGTLC1 and hypothyroidism: Apart from a slight increase in gamma-glutamyl transpeptidase, the patient's ALT and AST were normal and the Child-Pugh class was A. During immunotherapy, the patient's TSH level was increased, but the levels of FT3, FT4, TPOAb, and TGAb were all in the normal range and the patient had no clinical symptoms of hypothyroidism.