[MIM 610 443]

Prevalence: 1/16,000. Chromosomal abnormality due to a mutation of the KANSL1 gene (17q21.31), or, more frequently, to a microdeletion on 17q21.31 ranging in size between 500 and 650kb and including at least six genes:

C17 or F69 , CRHR1 , IMP5 , MAPT , STH and KIAA1267.

It is characterized by:

-        developmental and psychomotor retardation of variable importance

-        hypotonia, especially in the neonatal period and in early childhood: sucking problems

-        facial dysmorphism: elongated face, high and wide forehead, downslanting palpebral fissures, epicanthus, nose either tubular or pear shaped with a bulbous tip, large and prominent ears, prominent lower lip. This facial dysmorphism can evolve with age, with an elongation of the face and coarser facial characteristics.

-        characteristic friendly behavior.

-        epilepsy (50 %)

-        cardiac anomalies: ASD, VSD, pulmonary stenosis

-        short stature, pectus excavatum, scoliosis, long and thin fingers

-        ligament hyperlaxity, dislocation of the hip

-        renal and urological anomalies

-        abnormal hair pigmentation and consistance

Anesthetic implications:

epilepsy, preoperative echocardiography, check renal function, short stature, scoliosis

References :

-        Kavakli AS.
Anaesthesia and orphan disease: a child with Koolen-de Vries syndrome.
Eur J Anaesthesiol 2018; 35: 980-1.

Updated: November 2018