Pallister-Hall Syndrome

Congenital syndrome characterized by hypothalamic hamartoblastoma with panhypopituitarism. Other features include craniofacial abnormalities, polydactyly, endocrine, cardiac, and renal defects. Laryngeal cleft and epiglottis dysplasia are common. Mild retardation is most often present.

CAVE (Cerebro-Acro-Visceral Early Lethality) Complex; Hall-Pallister Syndrome; Congenital Hypothalamic Hamartoblastoma, Hypopituitarism, Imperforate Anus, and Postaxial Polydactyly Syndrome.

This medical condition was described in 1980 by Judith G. Hall, an American geneticist, after observing these anomalies in six children. Philip D. Pallister, an American pediatrician and human geneticist, contributed to the genetic determination before his retirement in 1981.

Prevalence estimated to fewer than 1000 patients.

Associated with mutations in the GLI3 gene (short arm chromosome 7), a gene regulating other genes in early fetal development; most cases are sporadic, but cases of autosomal dominant inheritance have been observed.

Unknown.

Hormonal deficiencies; hypothalamic hamartoblastoma on MRI: it extends from the optic chiasma to the interpeduncular fossa, thus replacing the hypothalamus and nuclei originating from the embryogenic hypothalamic plate. Other associated cerebral anomalies may be present, including occipital encephalocele and Dandy-Walker malformation.

At birth: variable syndactyly and postaxial polydactyly with imperforate anus or variable degrees of rectal atresia; flat midface and nasal bridge; short nose with anteverted nares; external ears anomalies (absent auditory canals, malformed pinnae); micrognathia. Laryngeal cleft and dysplastic epiglottis are common. Bifid epiglottis is present in more than 40% of patients. Congenital heart disease: atrial septal defect, ventricular septal defect, patent ductus arteriosus, coarctation of aorta. Patients present with kidney dysplasia, testicular hypoplasia, micropenis, and cryptorchidism. Severely affected infants have impaired pituitary function: growth hormone deficiency and hypothyroidism are common; hypocortisolemia and diabetes insipidus are rarer. Hypoplastic adrenal glands. Some cases with precocious puberty. Bifid, hypoplastic, or absent epiglottis at laryngoscopy. Cases of laryngeal cleft have been described. Abnormal tracheal cartilage and anomalies of pulmonary lobation and lung hypoplasia or dysplasia is frequent. The majority of patients described have died by 3 years of age, the major cause of neonatal death being hypoadrenalism. Long-term survivors are on hormonal therapy from birth or early infancy. Headaches are common. Some patients have seizures. Intelligence is usually normal.

Check hormonal treatment: it should be continued up to the day of surgery and adapted with the help of the child's endocrinologist; echocardiography to exclude the presence of a congenital heart defect. A proper evaluation of the airway must be done to eliminate the presence of a laryngeal cleft. The medical history for seizure and antiepileptic medication must be reviewed.

Tracheal intubation may be difficult in case of microretrognathia and in the presence of an anomalous epiglottis; anomalies of the larynx or trachea may require an endotracheal tube a size smaller than predicted by age. In the presence of a laryngeal cleft, the maintenance of spontaneous respiration is highly recommended. The anesthetic conduct is dictated by the presence of cardiac anomaly.