Endocrine Abstracts

Introduction: Pendred syndrome is a rare autosomal recessive condition characterised by sensorineural deafness, goitre and impaired iodine organification. We report a case of a 43-year-old female who presented with hearing impairment, and the development of a multinodular goitre with tracheal compression. Perchlorate testing and genetic studies confirmed a diagnosis of Pendred syndrome. She subsequently underwent partial thyroidectomy and requires lifelong follow-up.

Case report: A 43-year-old Afro-Caribbean female presented at age 30 in our endocrine clinic with a 15-year history of goitre, where she described only hoarseness of voice. She has a background of childhood deafness bilaterally, a presumed complication of measles. She was noted to have negative thyroid autoantibodies, TSH 2.7 mU/l and FT₄ 10 pmol/l. She was discharged, but re-referred 8 years later due to increasing goitre size, resulting in dysphagia and difficulties breathing. Ultrasound and CT imaging revealed a sizeable multinodular goitre with right-sided tracheal deviation and lateral compression. She underwent a left lobectomy and isthmusectomy, but suffered vocal cord palsy complications, and did not undergo a right lobectomy. A positive perchlorate test followed by genetic studies, which demonstrated homozygous c.1151A>G, confirmed the diagnosis of Pendred syndrome. She requires lifelong follow-up.

Discussion: The combination of sensorineural deafness and goitre should alert the clinician to the possibility of Pendred syndrome, which is due to biallelic mutations in the SLCC26A4 gene. As the condition is autosomal recessive, a full family history should be taken. Although the thyroid goitre is usually benign, hypothyroidism occurs in up to 40% of cases. Even following surgery, re-growth of goitre can occur. The perchlorate test, a radiolabelled iodine scan, aids in the diagnosis of Pendred syndrome, which shows poor orgnanification of iodine. Genetic testing (homozygosity of c.1151A>G) confirms the diagnosis.