Adams-Oliver Syndrome (AOS)

Very rare inherited disorder characterized by defects of the scalp associated with multiple scarred and hairless areas that usually have dilated blood vessel directly under the skin. Scalp defects are present at birth. The extremities are either short (hypoplastic fingers and toes) or characterized by absent hands and lower legs. Congenital heart defect must be ruled out.

Congenital Scalp Defects with Distal Limb Reduction Anomalies; Absence Defect of Limbs, Scalp, and Skull.

Described in 1945 by Forrest H. Adams and C.P. Oliver, both American physicians.

Rare congenital abnormality. Approximately 100 cases have been described. Both sexes are equally affected.

In most families, the disorder clearly follows an autosomal dominant pattern of inheritance, but in some families the penetrance is reduced. No genetic background information or molecular data concerning the Adams-Oliver syndrome are available.

The pathophysiologic mechanism remains unknown, but a vascular pathogenesis with interruption of early embryonic blood supply to the subclavian arteries has been discussed.

The diagnosis is made clinically with findings of a scalp defect combined with distal limb anomalies.

For some researchers, this syndrome represents one of many forms of Aplasia Cutis Congenita. The congenital midline scalp defect often is solitary and associated with an underlying skull defect and dilated scalp veins converging to the skin defect. Typically, these lesions appear as small ulcerations that may heal spontaneously. Larger lesion may require surgery with skin grafting and often are associated with an underlying bone defect. In a small number of patients, these defects have resulted in death secondary to infection (fatal meningitis) or hemorrhage from the sagittal sinus. However, the clinical expression of this syndrome is highly variable. The defect of the cranium usually is not associated with nervous system abnormalities. Intellectual development seems normal. However, hydrocephalus, microcephaly, seizure disorder, and mental retardation have been reported in a few patients. Limb reduction anomalies (found in 80% of patients) are most commonly characterized by hypoplastic or absent distal phalanges and in some cases absence of the lower leg below the midcalf level. On the upper limb, the metacarpals or the fingers may be completely absent or the terminal phalanges of the fingers are hypoplastic. Other anomalies may include congenital heart defects (present in up to 13% of patients, e.g., tetralogy of Fallot, pulmonary atresia, double-outlet right ventricle, pulmonary vein stenosis, atrial septal defect), cerebral arteriovenous malformations, encephalocele, microphthalmia, cleft lip/palate, cutis marmorata telangiectatica congenita, Epidermolysis Bullosa, thin and hyperpigmented skin, woolly hair, and supernumerary nipples. Bronchial and renal anomalies and portal hypertension have been described in a small number of patients.

In neonates, look carefully for associated abnormalities. Cardiac malformations should be excluded by echocardiography. The anesthesiologist must be aware of the possible association with Epidermolysis Bullosa. Look for possible complications of large or multiple scalp defects, such as infection (meningitis) or hemorrhage. Obtain complete blood count, electrolytes, ...