假性甲状旁腺功能减退症（pseudohypoparathyroidism, PHP）是一组由外周靶组织对甲状旁腺激素（parathyroid, PTH）抵抗所致的一组临床综合征，其临床特征主要为低钙血症、高磷血症，和由此引起的手足搐搦、惊厥或癫痫样发作。PHP 1b型患者常无特异性体征，临床表现多样，若不及时完善生化、PTH等检测，易延误诊断。本文报道1例以发作性惊厥为主要表现的PHP患儿，男性，11岁，其血清钙、游离钙均降低，同时PTH明显升高，血磷升高，尿钙、尿磷低，基因检测显示该患儿STX16基因5-7号外显子杂合缺失，GNAS-A/B母源甲基化缺失，检查其父母STX16/GNAS-AS1/GNAS等基因/区域拷贝数变化及甲基化情况，结果均未见异常。该患儿明确诊断为新发STX16基因突变所致常染色体显性遗传型PHP 1b型（autosomal dominant inheritance-PHP 1b， AD-PHP 1b）。予骨化三醇及钙剂口服治疗后，其血钙逐渐恢复正常，未再惊厥发作，目前仍在跟踪随访。目前国内未见报道男性STX16基因新发突变导致AD-PHP 1b型病例。

Pseudohypoparathyroidism (PHP) is a group of clinical syndromes caused by peripheral target tissue resistance to parathyroid hormone (PTH). Its main clinical features are hypocalcemia, hyperphosphatemia, and resulting tetany, convulsions, or epileptoid seizures. Patients with PHP 1b often present no specific signs and have diverse clinical manifestations, and if biochemical tests and PTH measurements are not performed in time, the diagnosis is likely to be delayed. This paper reports a 11-year-old boy with episodic convulsion as the main manifestation. The boy had low serum calcium and ionized calcium, significantly increased PTH, elevated serum phosphorus, and low urinary calcium and phosphorus. Genetic testing revealed heterozygous deletion of exons 5-7 of STX16 gene and loss of maternal methylation at GNAS-A/B. Parental testing for copy number changes and methylation status of STX16/GNAS-AS1/GNAS genes/regions showed no abnormalities. The patient was definitively diagnosed as a male pediatric case of autosomal dominant PHP 1b (AD-PHP 1b) caused by a new mutation of STX16. After oral treatment with calcitriol and calcium supplements, the patient's serum calcium gradually returned to normal, and no further convulsive seizures occurred. The patient is currently under follow-up. At present, no cases of male AD-PHP 1b caused by a new mutation of STX16 have been reported in China.