ABSTRACT

Non-ketotic hyperglycinemia (NCH) is a life-threatening autosomal recessive hereditary metabolic disease characterized by accumulation of a large amount of glycine in serum and cerebrospinal fluids. A 3-month-old girl was referred to our intensive care unit due to poor feeding, respiratory failure and refractory seizures. Physical examination revealed poor general condition, hypotony, lethargia and quite shallow breathing. Her complete blood count, peripheral blood smear, liver and kidney function tests, serum electrolytes, blood gases, C-reactive protein, procalcitonin, ammonia and lactate levels were within the normal ranges. Her tandem mass and urine organic acid analyses were also normal. Blood and cerebrospinal fluid cultures were sterile. A suppression-burst pattern (modified hypsarrhythmia) was detected in electroencephalographic evaluation. The cerebrospinal fluid glycine level was elevated more than 10 folds and the cerebrospinal fluid glycine/plasma glycine ratio was 0.15. According to these laboratory findings, she was diagnosed with NCH and dextromethorphan and sodium benzoate therapies were initiated. Ventilatory support was provided due to respiratory failure. She was followed by the Synchronized intermittent mandatory ventilation + pressure support mode, and ketamine (2 mg/kg, iv) therapy was initiated. At the 7^th day of this therapy, there was no need for mechanical ventilation anymore. This case gives us an idea about the efficiency of ketamine in ceasing NCH patients from mechanical ventilation at early stages of disease.

Keywords: Non-ketotic hyperglycinemia, respiratory failure, ketamine