ICD-9-CM 359.23 is a billable medical code that can be used to indicate a diagnosis on a reimbursement claim, however, 359.23 should only be used for claims with a date of service on or before September 30, 2015. For claims with a date of service on or after October 1, 2015, use an equivalent ICD-10-CM code (or codes).
A syndrome of short stature; generalized myotonia with contractures of major joints, microstomia, and muscle rigidity; ocular anomalies, mainly blepharophimosis; and characteristic facies marked by pinched or frozen smile puckered lips. Some degree of mental retardation occurs in about 25% of patients. The affected children usually appear normal at birth and the symptoms become recognizable at 1 to 3 years of age. Malignant hyperthermia is a potentially lethal hazard during anesthesia