ESPE Abstracts

Introduction: Kenny-Caffey Syndrome Type 2 (KCS2) is a rare autosomal dominant genetic disorder caused by variants in the FAM111A gene, leading to cortical thickening and medullary stenosis of long bones. It is characterized by primary hypoparathyroidism, electrolyte disturbances, skeletal dysplasia with delayed closure of the anterior fontanelle, hypertelorism, and short stature. Intellectual development is normal.

Case Report: We present the case of a 2-month-old male infant, born to non-consanguineous parents. The pregnancy was uneventful, and delivery was term and normal, with good adaptation to extrauterine life. Birth anthropometrics were appropriate for gestational age. At two weeks of age, the infant began experiencing seizures that were difficult to control. Laboratory tests revealed severe hypocalcaemia and hypomagnesaemia, needing prolonged intravenous supplementation. Parathyroid hormone (PTH) levels were undetectable, with elevated serum phosphate and alkaline phosphatase levels. 1,25-dihydroxy vitamin D levels were adequate. Physical examination showed a frontal bossing associated with a wide anterior fontanelle. After stabilization and transition to oral calcium and magnesium supplementation, genetic testing revealed the c.170G>A (p.Arg569His, R569H) variant on chromosome 11q12.1 in the FAM111A gene.

Discussion: The treatment for Kenny-Caffey Syndrome Type 2 is symptomatic, focusing on correcting phosphocalcic metabolism imbalances and vitamin D supplementation. Due to the potential for ocular abnormalities, an ophthalmological evaluation is recommended.