<p>  When a preoperative examination reveals an elevated creatine kinase (CK) level, the cause of the elevation is usually sought before planning general anesthesia. However, a definitive diagnosis may not always be possible ; in such cases, careful attention must be paid to general anesthesia management. Here, a 6-month-old girl with bilateral cleft lip and palate is reported. No other remarkable clinical or family history findings were noted. However, blood tests showed persistently high CK levels, strongly suggesting the presence of a disease involving muscle tissue ; nevertheless, a definitive diagnosis could not be made. Therefore, considering the risk of complications (such as malignant hyperthermia), cleft lip corrective surgery was performed under total intravenous anesthesia (TIVA). The patient’s intraoperative vital signs were stable. No postoperative respiratory complications were noted. She was subsequently found to be a carrier of Duchenne muscular dystrophy (DMD). DMD carriers can have the same pathophysiology as DMD patients. Therefore, a thorough preoperative evaluation and measures to prevent intraoperative and postoperative complications were considered important in the present case.</p>