One child, two syndromes

We present a first child of non-consanguineous parents. During pregnancy, fetal facial dysmorphism was suspected and amniocentesis was performed. A normal female karyotype was found. The girl was born small for gestational age and presented marked nasal hypoplasia. She was admitted to the neonatal intensive care unit and discharged at the age of 4 weeks. The girl was readmitted to the hospital at the age of 3 months with failure to thrive. All growth parameters were below the third centile. Dysmorphic features, including depressed nasal bridge, nasal hypoplasia, asymmetric eyes and overriding toes, were observed. Diagnostic work-up revealed obstructive sleep apnea syndrome, hypoplasia of the maxilla, laryngomalacia and stenosis of the left pulmonary artery. Subtle skeletal anomalies were found on the Xrays. CGH-array was performed with the 44k Agilent array. The results showed deletion of the region for a well-known microdeletion syndrome, which was clinically not suspected. With time, the girl developped mild developmental delay and the values of some laboratory markers are in accordance with what is seen in the microdeletion syndrome. However, a second monogenic condition is also present and the sum of these two syndromes gives rise to a particular phenotype.