A simple method of determining 4-hydroxyisovaleric acid and its level in a patient with isovaleric acidemia

We developed a simple and rapid method for the quantitative determination of 4- hydroxyisovaleric acid using the conversion of this acid to the corresponding lactone,and measured its levels in the plasma of a patient with isovaleric acidemia during an episode of severe ketoacidosis. 4-Hydroxyisovaleric acid reached a peak two days after plasma isovaleric acid was at its highest level.