Etiologies

Over 70 specific etiologies are identified in the 2017 National Deaf-Blind Child Count. Some are exceedingly rare, with less than five cases. Others are much more prevalent. There are 13 etiologies with at least 100 cases, and one—Cornelia de Lange syndrome—with 99.

Complications from prematurity continues to be the most commonly identified etiology. The prevalence of CHARGE syndrome continues to increase. In 2017 there were 933 children and youth identified as having CHARGE syndrome. While still relatively rare, the prevalence of children with Stickler syndrome and Dandy Walker syndrome has also increased. About 19.0% of the children and youth have no determined etiology.

Overall, the total number of children and youth identified with a prenatal congenital or postnatal non-congenital etiology has declined from 2,732 to 2,551 over the past five years, while the number with hereditary syndromes and disorders has increased from 3,945 to 4,482. Hereditary syndromes and disorders now account for 44.8% of all identified etiologies. Prenatal congenital complications account for 13.9% of identified etiologies and postnatal non-congenital complications account for 11.6% of identified etiologies. Complications from prematurity account for 10.5% of identified etiologies and 19.2% of the children and youth had no identified etiology at the time data was collected.

Congenital Rubella Syndrome (CRS), which has long been associated with the development of the deaf-blind technical assistance system, is no longer a prevalent etiology. In 2017, there were 41 individuals whose etiology was identified as CRS, down from 89 in 2010. Over 75% of these individuals are over 10 years of age and over 50% are 15 years of age or older.

The heterogeneous nature of the population cannot be overstated. The etiologies or causes of deaf-blindness bring unique issues and challenges. Some are relatively more common, such as CHARGE syndrome, Down syndrome, Usher syndrome, and Cytomegalovirus. Some are very rare, with less than five individuals reported nationally, such as Batten disease, Prader-Willi, and Kearns-Sayre syndrome.