A novel mutation in exon 18 of <i>FGFR1</i> causing hypoparathyroidism: A case report

Hypoparathyroidism is a rare endocrine condition characterized by insufficient secretion of parathyroid hormone (PTH), resulting in abnormally low calcium levels (hypocalcemia) and elevated phosphate levels (hyperphosphatemia) in the blood. This report describes a man in his late 30s with a chronic skin condition marked by dryness and desquamation. He occasionally experienced mild perioral numbness. Over the past year, he developed recurrent neuromuscular irritability, including worsening perioral numbness, tingling or numbness in the hands and feet, and muscle spasms consistent with tetany. He was diagnosed with hypoparathyroidism, and his symptoms improved markedly after calcium and calcitriol supplementation. Genetic testing revealed a novel heterozygous c.2298C>G (p. Tyr766Ter) mutation in exon 18 of the fibroblast growth factor receptor 1 gene. This case report aimed to describe this novel mutation and its potential role in the pathogenesis of primary hypoparathyroidism and to discuss relevant diagnostic and therapeutic management strategies. In addition, it broadens our understanding of genetic mutations associated with hypoparathyroidism and provides clinically relevant diagnostic information that may benefit future patients with the similar genetic alteration. Furthermore, it underscores the importance of genetic analysis in elucidating the heterogeneity and complexity of hypoparathyroidism, thereby supporting the development of more precise and tailored treatment approaches.