J Zheng

Abstract

Objective: The Down-Klinefelter syndrome (48,XXY,+21) is a rare chromosome abnormality. The aim is to describe the clinical features and diagnosis of rare event. Method: Case report and literature review Case presentation: A newborn boy was presented to our unit because of cyanosis for 13 hours after birth. He was born at 38 weeks' gestation without asphyxia via caesarean section due to oligohydramnios. He presented cyanosis about 30 minutes after birth and relieved after oxygen supplied. The boy was 50 cm in length, 2.7 kg in weight with head circumference of 33.5 cm. His respiratory rate was about 60 times every minute without rales in the lung. He had the characteristic features, including flat facial profile, flat nasal bridge, short thick neck, low-set ears, high palate, low hair line, simian crease, and slanted palpebral fissures. Hypotonia was noted as well. Chest X-ray showed exudative lesions in the lung. The Doppler echocardiography showed atrial septal defect with bidirectional shunt, enlarged right heart, and mild tricuspid regurgitation. Cytogenetic analysis confirmed a karyotype of 48,XXY,+21. Conclusion: Down-Klinefelter syndrome is a rare disease. Karyotyping should be performed for all patients with suspected Down syndrome anyway, even born from young parents.