Kleefstra syndrome (KS) is an autosomal dominant disorder caused by a 
chromosomal deletion at 9q34.3 resulting in pathogenic variants of the gene that 
codes for the enzyme, euchromatin histone methyltransferase 1 (EHMT1). KS is a 
rare, yet clinically relevant congenital disorder for anesthesiologists because 
of its potential for cardiac and craniofacial involvement. We present a 
3-month-old patient with KS who required anesthetic care for diagnostic 
laryngoscopy and rigid bronchoscopy. The end-organ effects of KS are reviewed 
and our anesthetic care presented.