Opitz C syndrome: Trigonocephaly, mental retardation and craniofacial dysmorphism
We describe a 4-year-old female child with a dysmorphic and neurological syndrome of trigonocephaly, mental and psychomotor retardation and dysmorphic facial features. The anomalies of the face were the following: slight upward palpebral fissures, ocular hypertelorism, depressed nasal bridge, hypoplastic nasal root, short nose with anteverted nares; small low set ears, smooth broad philtrum and thin upper lip. The patient had important cerebral anomalies with diffuse alterations in white matter that caused developmental delay with verbal and nonverbal disabilities and severe learning difficulties. This clinical presentation is compatible with the diagnosis of the Opitz C syndrome, a heterogeneous disease of multiple neurological and craniofacial abnormalities. The physical sign more detectable and notorious is the trigonocephaly that is manifested by a prominent metopic suture, but also can be distinguished the other minor facial anomalies that are found in the eyes, nose, mouth and ears that constitute the phenotype of the disorder. The neurological development was altered by the compression of the cerebral frontal lobes with narrowing of this cerebral area, producing hypotonia with muscle weakness, epileptic episodes manifested by seizures, and neurobehavioral and neurocognitive disorders. This syndrome is a very rare genetic disorder with autosomal recessive inheritance trait; our patient had no chromosomal abnormality in the usual karyotype but the fluorescence in situ hybridization (FISH technique) showed a balanced translocation between the chromosomes two and eleven: t(2:11) (q32.2/q24).