Investigation of Hypoglycaemia in Childhood
It is most important to ensure that appropriate samples are collected at the time of the hypoglycaemia. Certain tests should be performed as soon as practically possible, including:
- fluoride oxalate blood; free fatty acids, 3 hydroxybutyrate, lactate
- urine; organic acids
Other tests should then follow as indicated either by the clinical presentation or the results of the earlier tests.
Absolute values for FFA (free fatty acids) and 3 hydroxybutyrate are not stated as the diagnosis is developed on the relative concentrations of these two analytes rather than their absolute values.
Urine dip-stick tests for ketones detect acetoacetate but not 3 hydroxybutyrate and therefore cannot be relied upon to detect ketonuria with disorders of hepatic redox states and/or intracellular acidosis.