This neonate was born at 34 weeks' gestational age via elective cesarean section because of breech presentation. He weighed 1950 g, and his Apgar scores were 7 and 8, at 1 minute and 5 minutes, respectively.
He was noted to have facial asymmetry. While resting, his upper face (including forehead skin folds and nasolabial folds) appeared symmetric (A); while crying, his mouth pulled to the lower right side (B). Other physical findings were normal. There was no family history of this malformation. The mother's health had been unremarkable during her pregnancy, and she had not taken any medications.
An MRI scan of the brain and an echocardiogram were normal. The patient's karyotype was also normal, and results of a fluorescent in situ hybridization (FISH) study for a 22q11.2 chromosomal deletion were negative. Atiya Khan, MD, of Fort Wayne, Ind, and Aaron Provance, MD, of Morgantown, WVa, determined that the asymmetric facies were the result of an absent left depressor anguli oris muscle.
Asymmetric crying facies syndrome is a very rare disorder associated with unilateral absence or hypoplasia of the depressor anguli oris muscle. Usually, this is a cosmetic defect and an isolated finding. Nevertheless, the condition may be associated with underlying anomalies: a careful workup--which includes MRI, an echocardiogram, and karyotyping--is therefore indicated. For example, heart defects may accompany the facial asymmetry (cardiofacial, or Cayler, syndrome). The gene map locus for Cayler syndrome has also been linked to the CATCH 22 (cardiac defect, abnormal facies, thymic hypoplasia, cleft palate, hypocalcemia) and VACTERL (vertebral anomalies, anal atresia, cardiac malformations, tracheoesophageal fistula, renal anomalies, limb abnormalities) associations.1 Other malformations include GI tract and genitourinary tract anomalies, CNS defects, microcephaly, micrognathia, and mental retardation.
The male-to-female ratio of this malformation is 2:1.2 In one study of 5532 infants, the incidence of absence or hypoplasia of the depressor anguli oris was 0.3%.3 Rarely, this malformation is familial; in one study, 3 of 12 siblings were affected.4
This disorder is often confused with facial nerve palsy. Patients with lower motor neuron facial nerve palsy have an asymmetric forehead and nasolabial folds; they are unable to close the eye completely on the affected side. In patients with an absent or hypoplastic depressor anguli oris muscle, the forehead skin folds and nasolabial folds are symmetric and eye closure is normal bilaterally. Affected newborns usually have no difficulty in feeding or trouble with drooling. The malformation becomes less apparent with age.
Treatment is for cosmesis. Parents need to be reassured that this condition is not caused by birth trauma.