A Case of CATCH22 Syndrome with Normal Parathyroid Function

ABSTRACT

CATCH 22 is a medical acronym for cardiac defects, abnormal faces, thymic hypoplasia, cleft palate, and hypocalcemia, and a variable deletion on chromosome 22. It includes DiGeorge syndrome, conotruncal anomaly face syndrome, and velo-cardio-facial syndrome. It has a prevalence estimated at 13,000-16,000. Most deletions occur at de novo, but autosomal dominant inheritance is observed in 6-10% of cases. Hormonal disorders are common in patients with CATCH22 syndrome. While hypoparathyroidism was the predominant endocrine disturbance that has been documented in the DiGeorge syndrome, other hormonal defects, such as growth hormone deficiency, hypothyroidism, and hyperthyroidism have been occurred in patients with CATCH22 syndrome. The spectrum of parathyroid gland dysfunction in this syndrome ranges from severe neonatal hypocalcemia to normal parathyroid function. Most patients are usually diagnosed in young age, but a few patients with mild abnormality are presented later in life. We report a case of CATCH22 syndrome with normal parathyroid hormone and calcium level in an adult. The diagnosis of CATCH22 syndrome was confirmed by fluorescence in situ hybridization analysis.