Question
A 2-year-and-a-half-old child can only produce simple syllables, has an abnormal gait, cannot run or jump, poor fine motor skills, difficulty swallowing, drooling, and incontinence of urine and feces. Is there a way to diagnose methylmalonic acidemia?
Answer
Mild cases of methylmalonic acidemia often have lower levels of methylmalonic acid. Consumption of propionate and methylmalonic acid precursors or amino acids may increase the accumulation of methylmalonic acid, even leading to ketosis or acidosis. Some cases are also accompanied by low methionineemia and cystathioninuria. Methylmalonic acid concentration can be detected in amniotic fluid or urine from pregnant mothers in the second trimester, or enzyme activity can be measured in cultured amniotic cells for prenatal diagnosis.