Familial Paraganglioma Syndrome Type 1: When Genetic Screening Determines Reference

Introduction: The paraganglioma syndrome type 1 (PGL1) is characterized by paragangliomas, caused by germline mutations in the SDHD gene. Case Report: 46 year-old woman, asymptomatic, referred to the Endocrinology outpatient department for being a carrier of the IVS3 c.315-2A>C mutation in the SDHD gene. The index case was her sister, who had apparently secretory multiple neck paragangliomas. Neck magnetic resonance imaging revealed two masses suggestive of paragangliomas and the octreoscan identified two hot spot lesions, coincident to the masses described in the magnetic resonance imaging. The larger left neck mass was surgically removed and the histology confirmed the PGL diagnosis. Discussion: We report this case due to: 1) the new reality that it highlights - the one of the "patients" detected by genetic screening; 2) the type of mutation co-segregating with the disease - a splice-site mutation, probably a splice-acceptor mutation (IVS3 c.315-2A>C), which carries an increased risk of pheochromocytomas or sympathetic paragangliomas.