Endocrine Abstracts

Background: DiGeorge syndrome (DGS) is the rare genetic disorder caused by a 22q11.2 chromosome microdeletion. The main clinical features are associated with defective development of the pharyngeal pouch system and usually include congenital heart disease, hypoplasia of thymus resulting in immune deficiency and hypoparathyroidism. Also DGS patient has characteristic long face with narrow palpebral fissures, broad nasal bridge, micrognathia and small mouth, small dysmorphic ears.

Aim: To describe the 20 years old patient with delayed diagnosis of DGS due to unspecific disease manifestation.

Clinical case: Ventricular septal defect and patent foramen ovale were diagnosed at birth and repaired when the patient was 3 years old. Since childhood pediatrics have noted moderate delay in the cognitive function and rare episodes of febrile seizures up to 3–4 times a year. However, hypoparathyroidism was diagnosed only at the age of 17 years, when the low serum calcium levels were first determined. Despite the prescribed calcium supplementation the febrile convulsions have persisted. Upon admission to our center the patient presented with periodic muscle convulsions in the upper and lower extremities, recurrent headaches, stabbing pain in the heart, weakness, memory loss. Physical examination revealed mild facial dimorphism (wide and flat nose, small low-set ears), hyperkyphosis, obesity (BMI 30.0 kg/m²). Pathological laboratory findings were as follows: corrected calcium 1.38 mmol/L (2.1–2.55), ionized calcium 0.68 mmol/l (1.03–1.29), phosphorus 3.0 mmol/l (0.74–1.52), PTH 9.13 pg/ml (16–65). CT-scan showed the calcifications in basal ganglia. No clinical and laboratory evidence of significant immunodeficiency was found in our patient. He had been managed by combined therapy with alfacalcidol (1 μg per day), cholecalciferol (7500 IU per week), calcium (6000–8000 mg per day) for one year. The follow-up examination demonstrated the significant improvement as persistent normocalcemia, absence of convulsions and paresthesia, posture straightening, muscle weakness reduction, weight loss and increased physical activity. A genetic study identified a large chromosome 22q11.2 deletion and the diagnosis was confirmed for DGS. Besides there were found the insertion in X-chromosomal Sox3 gene that can explained the mental retardation.

Conclusion: Clinical presentation of DGS can be variable and the severity of each organ involved is wide. Although the symptoms associated with hypocalcemia suggest a wide range of diseases, DGS should be considered in children and young adults with concomitant cardiac defects, development delays and other suspicious features.