Sanjad-Sakati Syndrome

Genetically transmitted polymalformative syndrome characterized by hypoparathyroidism, growth retardation, developmental delay, seizures, and facial dysmorphism (e.g., micrognathia).

Hypoparathyroidism with Short Stature, Mental Retardation, and Seizures; Kalam Hafeez Syndrome.

Autosomal recessive. The genetic locus is on the short arm of chromosome 1 at position 42-43 (1q42-q43).

Virtually undetectable levels of parathyroid hormone resulting in hypocalcemia associated with hypophosphatemia. Growth hormone and insulin-like growth factor levels were also found to be low in affected children. Treatment with human growth hormone produced a rapid increase in the height and weight of one affected 5-year-old child. It was speculated that the hypothalamus plays a role in the regulation of both parathyroid hormone and growth hormone.

Clinical features plus the onset of hypocalcemia with very low parathyroid hormone levels, usually in the newborn period. Usually consanguineous parents.

Early onset hypocalcemia, which may be asymptomatic, associated with hyperphosphatemia. Very low parathyroid hormone levels, and possibly low growth hormone and insulin-like growth factor. Consequently, patients have retarded growth (more than 2 SD [standard deviations] below the mean). Facial dysmorphism is very consistent, especially within families with more than one affected child: microcephaly, deep-set eyes, depressed nasal bridge with beaked nose, long philtrum, thin upper lip, micrognathia, and large, floppy ear lobes. Most children have skeletal defects, such as medullary stenosis. Developmental delay is usual. Seizures may occur. Reduced numbers of some T-cell subsets have been detected in some patients, but immunological function seems normal.

An anesthesiology consultation is recommended before elective surgery. Detect and treat hypocalcemia/hyperphosphatemia. Evaluate the patient carefully for potential difficult tracheal intubation.

A difficult direct laryngoscopy and tracheal intubation may be expected, especially in patients with micrognathia. If so, spontaneous respiration should be maintained until the airway is secured and lung ventilation confirmed. Considerations of uncorrected hypocalcemia: long QT interval and associated dysrhythmias, hypotension caused by peripheral vasodilation and ventricular dysfunction, seizures, and increased neuromuscular irritability (prone to laryngospasm). Respiratory or metabolic acidosis can further decrease ionized calcium by increasing protein binding, and thus increase the likelihood of the above-mentioned considerations. Affected patients may be more sensitive to nondepolarizing muscle relaxants. Older children may be uncooperative as a result of developmental delay.

Increased sensitivity to muscle relaxants.

DiGeorge Syndrome: Recurrent infections, defective thymus functions, heart defects, and characteristic facial features caused by a deletion in chromosome 22.

Kenny-Caffey Syndrome: Congenital hypoparathyroidism associated with short stature, mental retardation, seizures, and a characteristic physiognomy. Cortical thickening of bones (osteosclerosis) and hypocalcemia. Autosomal recessive, which maps to the same region (1q42-q43); probably allelic to Sanjad-Sakati syndrome.