Symptomatic hypoparathyroidism based on a 22q11 deletion first diagnosed in a 43-year-old woman

Congenital hypoparathyroidism usually manifests in early childhood with hypocalcaemia with or without clinical characteristics. This report describes a Caucasian woman who, at the age of 43 years, was diagnosed with dysgenesis of the parathyroid glands due to a de novo microdeletion in chromosome 22q11 or DiGeorge syndrome. This syndrome is characterised by a considerable variability in clinical symptoms, including heart defects, thymic hypoplasia and mental retardation. Our patient presented with generalised convulsions due to extreme, symptomatic hypocalcaemia. The convulsions had been apparent for 18 months at the time of the diagnosis. Remarkably, whereas parathyroid hormone levels were undetectable, the 1,25-dihydroxy vitamin D level was normal. Chromosome 22q11 deletion was confirmed by fluorescence in situ hybridisation analysis.