ABSTRACT
We experienced a case of familial hypoparathyroidism with an autosomal dominant pattern of transmission and performed molecular analysis of the calcium-sensing receptor (CASR) gene. The patient was a female neonate, born by cesarean section at term because of breech presentation. Her mother had been diagnosed with idiopathic hypoparathyroidism at the age of 9 yr and had been receiving vitamin D treatment since then. At birth, the patient's serum calcium concentration was 8.4 mg/dl, but it fell to 4.0 mg/dl on the fifth day after birth. Furthermore, her serum intact PTH level was inappropriately low, while hyperphosphatemia and hypomagnesemia were found. She was diagnosed with familial hypoparathyroidism, and was immediately started on oral administration of 1α(OH)D3 (0.1 µg/kg/day) and continuous intravenous infusion of 8.5% calcium gluconate. Additionally, trichlormethiazide was administered because of elevated urinary calcium/creatinine (Ca/Cr) ratio. Her serum calcium concentration gradually improved thereafter. In this case, autosomal dominant hypocalcemia (ADH) due to abnormality in the CASR gene was clinically suspected, but DNA sequencing analysis revealed no mutation of the CASR gene in either the patient or her mother. This result suggests that the patient's hypoparathyroidism may have been caused by abnormality in a gene other than CASR.
ABSTRACT
We experienced a case of fetal goitrous hypothyroidism in an infant delivered by a 33-year-old woman receiving 300 mg/day of propylthiouracil (PTU) for hyperthyroidism due to Graves' disease. A large fetal goiter (maximum diameter, 60 mm) was detected by magnetic resonance imaging (MRI) at 36 weeks of gestation. Initial fetal blood sampling revealed hypothyroidism with a serum thyroid-stimulating hormone (TSH) of 99 microIU/mL, free triiodothyronine (T(3)) of 1.97 pg/mL, and free thyroxine (T(4)) of 0.29 ng/dL. Consequently, a diagnosis of fetal goitrous hypothyroidism due to transplacental passage of maternal PTU was made. To reduce the risk of perinatal complications, 300 microg of levothyroxine sodium (L-T(4)) was administered into the maternal amniotic fluid twice between 37 and 38 weeks of gestation. Subsequent fetal MRI showed that the size of goiter had decreased. At 38 weeks and 5 days of gestation, a 3042-g male infant was born by cesarean section. There were no severe complications at delivery, although mild tachypnea was observed and the infant's thyroid gland was slightly enlarged. He was treated with L-T(4) for two weeks. At present, his growth and neurological development are normal. This case indicates that intrauterine therapy by the intraamniotic administration of L-T(4) can be effective in treating fetal goitrous hypothyroidism even during late gestation.
