This syndrome includes typical facies and cardiac anomalies. Many other malformations can be associated (endocrine and ophthalmic).
22Q11.2 Microdeletion Syndrome; VCS Syndrome; Shprintzen Syndrome; Sedlackova Syndrome; Takao Syndrome.
1:1,800 to 1:5,000 live births.
Autosomal dominant, (de novo: 80% of cases).
Observed anomalies result from microdeletion on 22q11.2.
Evocated in patients with typical facies (prominent nose and retrognathia, cleft palate), cardiovascular defects, and mental retardation. Proved by resolution banding and fluorescence in situ hybridization, which can find the 22q11.2 microdeletion (karyotype study is insufficient).
Clinical features also include multiple anomalies overlapping those encountered in other 22q11 deletions. Patients have short stature, overabundant hair, elongated face with mandible anomalies as in Pierre Robin Syndrome, malformed ears and eyes (inability to close the eyes, narrow palpebral fissures, malformed retinal vessels, blue sclerae, retinal colobomas, cataracts), and basilar impression. Intracranial lesions concern white matter and vermis. Language is slow and behavior disorders are observed. Immunologic and endocrine systems are often involved: adenoids, tonsils, and thymus are absent or small. In many cases, hypothyroidism and hypocalcemia can occur. Cardiovascular anomalies are frequent (85%), including right aortic arch, ventricular septal defect, tetralogy of Fallot, abnormal internal carotid arteries, and left subclavian artery. Other clinical signs supplement the disease: scoliosis, abnormal extremities, inguinal hernia, and anal anomalies.
Precautions before anesthesia
Evaluate patients for the possibility of cardiopathy (clinical, chest radiography, echocardiography) and airway (clinical, radiographs). Perioperative laboratory investigations should include calcemia, FT4, T3.
Direct laryngoscopy and tracheal intubation can be extremely difficult because of orofacial deformations and may require fiberoptic, laryngeal mask airway, or retrograde intubation. Spontaneous ventilation should be preserved until airway is secured and lung ventilation is confirmed. T-cell immunodeficiency requires strict aseptic procedures and specific blood (irradiated). Spine and extremity deformities need careful intraoperative position; regional anesthesia can be difficult to realize. Central venous access can be dangerous because of carotid and subclavian arteries malposition, use ultrasound guidance.
Avoid cardiodepressive drugs. Prophylactic antibiotics must be considered in cases of cardiopathy. The possibility of immunodeficiency is also an indication for antibiotics. Muscle relaxants should be avoided until airway is secured and lung ventilation is confirmed. Intraoperative fluid administration should be adapted to the cardiac function.
Other conditions to be considered
☞DiGeorge Syndrome: Characterized by hypocalcemia arising from parathyroid hypoplasia, thymic hypoplasia, and outflow tract defects of the heart. Results from microdeletion of the long arm of chromosome ...