Endocrine Abstracts

An 18 year old nursery nurse suffered two probable seizures. She was commenced on Phenytoin. She had had a cleft palate repair. Clinical examination revealed hypertelorism and short fourth metatarsals. Early papilloedema was noted. Routine blood tests showed profound hypocalcaemia of 1.2 mmol/l. Serum phosphate , magnesium and parathormone levels were normal. She suffered a further seizure and was given intravenous calcium. She suffered no further seizures and calcium levels were normal at discharge. Chromosomal analysis revealed a sub-microscopic deletion on the proximal portion of the long arm of chromosome 22 (22q11.2).

The CATCH 22 syndrome is an acronym for many of the defects (Cardiac defects, Abnormal facies, Thymic hypoplasia, Cleft palate and Hypocalcaemia) associated with the 22q11 microdeletion. Our patient was very unusual in remaining undiagnosed until her late teens. She was also unusual in the mode of presentation with seizures and papilloedema secondary to low calcium levels. This case indicates that all patients with late onset or recurrent hypoparathyroidism, often presumed to be autoimmune in aetiology, have analysis for the chromosome 22q11 microdeletion.