Nonketotic hyperglycinemia

National Taiwan University Hospital from 1996 to 2003 once the diagnosis and treatment or to assist the treatment of the six babies suffering from this disease. First they start the performance, including sleepiness and apnea, age at onset in about 1-3 days, especially all of the patients had neonatal hiccup phenomenon, and soon after birth can be observed. These patients will be gradually shown, in part or in whole body clonic cramps or muscle, anti-epileptic drugs on the control of these movements ineffective and usually required the use of several drugs at the same time can slow down the case of myoclonus. The diagnosis of all patients are in compliance with the non-ketone high glycine hyperlipidemia, including cerebrospinal fluid glycine values have increased, blood glycine values have increased, and cerebrospinal fluid glycine value on the blood values of the ratio of glycine greater than 0.08. These patients have specific changes in brain waves, in line with the non-ketone high glycine hyperlipidemia diagnosis.

These patients are at about one month beginning accepted for non-ketone high glycine Hyperlipemia rare drug treatment, including Sodium benzoate and Dextromethorphan. Sodium benzoate glycine concentration in order to reduce the special drug, but in these patients, the use of Sodium benzoate, although the blood glycine values returned to normal, but cerebrospinal fluid in glycine minimal value dropped to normal range inside.

Dextromethorphan (commonly known as merchandise Medicon) generally used to cough, but in these patients, the use of high doses of Dextromethorphan (per kilogram of body weight 20-35 mg) can effectively reduce muscle tension and spasm cramp slowed phenomenon. In addition, these patients in the neonatal period, both the phenomenon of intractable spasticity, you may need to simultaneously use several kinds of anti-epileptic drugs. In the after-effects, these patients have serious head, stiffness of limbs, paralysis, and severe developmental delay phenomenon. Since one of the three patients with aspiration pneumonia or related complications, respectively, died a year and a half, three-year-old and five-year-old. A patient's younger brother, but also the performance of 3-day-old when the symptoms begin, after adequate genetic counseling, the parents decided to give up aggressive treatment, so we do not have kids for intubation and the use of respirators, only to give oxygen therapy. The patient died five days. As regards the remaining two patients, the current three-year-old and a half years and separately for the two-year-old, brain MRI showed severe brain atrophy and white matter lesions, neurological development in babies less than four months.

Current non-ketone high neonatal glycine treatment of hyperlipidemia, although there is Sodium benzoate and Dextromethorphan such as medicine, but the outcome of treatment is still unsatisfactory. Even if early treatment, but also save the damaged nerve cells. As remnants of nerve cells, due to high concentration of glycine caused by sustained stimulation of intractable spasticity. Therefore, for such patients, whose prognosis is not very optimistic.

As for prenatal diagnosis, the current use of someone abroad enzyme test for human chorionic cells, but there are false positive and false negative of the question have to be overcome. If there were children at home and have found genetic mutation point, they may make use of genetic testing, to do prenatal diagnosis. But did not find mutations point home, they can only rely on an enzyme test to diagnose. Based on these difficulties, we give the parents of these six patients adequate genetic counseling, they must face their own future reproductive choices.

(Original published in the Journal of Child Neurology)