A Nonverbal 33-Year-Old Woman With Intellectual Impairment

James Robert Brasic, MD, MPH


October 20, 2021

Cornelia de Lange syndrome is a genetic disorder with phenotypic features apparent at birth. Patients with this syndrome have characteristic dysmorphic facies that include microbrachycephaly; synophrys; curly, unusually long eyelashes; a depressed nasal bridge; anteverted nares; maxillary prognathism; and micrognathia. Prenatal and postnatal growth deficiency, feeding difficulties, hypertonicity, motor delays, behavioral problems, and genitourinary and skeletal malformations are reported.[21] Intellectual disability can range from moderate to profound. A wide spectrum of phenotypic variation is observed.

Cornelia de Lange syndrome can be inherited as an autosomal dominant (gene location 5p13.2) or as an X-linked dominant condition. Males and females are both affected. The occurrence rate in the United States is about 1 in 10,000 live births. Many cases of Cornelia de Lange syndrome have been cited in the medical literature, and include case studies citing multiple affected siblings within families.

Down syndrome (also known as trisomy 21) is the most common human chromosome disorder and is caused by the presence of three copies of chromosome 21 in the patient's genotype. The population frequency in the United States is estimated to be 1 in 700 live births. It is a common cause of intellectual disability, and wide phenotypic variation is observed. Down syndrome is easily diagnosed by karyotype analysis. Interphase fluorescence in situ hybridization facilitates rapid diagnosis of Down syndrome. Laboratory assessments include investigations for possible mosaicism of trisomy 21.[22]

Patients with Down syndrome have a well-defined phenotype. Clinical findings include flattened occiput, shortened neck, midface hypoplasia, ocular findings (eg, epicanthal folds, upward slanting palpebral fissures, Brushfield spots), flattened nasal bridge, micrognathia, tongue protrusion, and low-set ears. Additional physical features can be extremity shortening; short, broad hands; single transverse palmar crease; noted extensibility and flexibility of joints; hypotonia; and diastasis recti. Patients are often diagnosed with hypothyroidism and cardiac and gastrointestinal problems. Congenital heart defects are diagnosed by echocardiography.[22]

Children with Down syndrome often have auditory and ocular concerns. Brainstem auditory evoked responses or auditory brainstem responses are used to identify hearing deficits. Ophthalmologic examinations identify visual deficits.

Cognitive delays may be present, along with problems associated with motor, language, and social development.[22] Intellectual disability can range from moderate to severe. An enriching home environment, early intervention, and integrated education efforts have shown a strong positive influence for children with Down syndrome. Genetic counseling, and continuity of medical care, benefit patients and their families. A comprehensive medical team approach is warranted to address involvement of various organ systems, such as the cardiac, endocrinologic, gastrointestinal, skeletal, and neurologic systems.[22]

Adolescents with Down syndrome merit counseling as they transition to adulthood. Caregivers can help them understand their physical activity limitations. Participating in rewarding physical activities, such as the Special Olympics, should be encouraged. Patients also may benefit from vocational training. Intellectual disabilities may limit their ability to advance to higher education. Providing long-term medical services and supportive living arrangements are warranted, as the average lifespan for these patients living in the United States is 60 years.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.