A case of vitamin B12--independent methylmalonic aciduria.

The reported case was a female infant aged 7 months with severe ketoacidosis associated with vomiting, dehydration and cardiorespiratory disturbances at the time of exacerbation of the disease. The analysis of urinary organic acids by the GC-MS method revealed methylmalonic aciduria. After placing the infant on a low-protein diet (1.5 g of protein per 1 kg of body weight) and initially vitamin B12 parenterally a striking clinical improvement with evident progress in psychomotor development of the child was achieved.