Lactic dehydrogenase (LDH) deficiency
Incidence
Probable AR. Rare.
Clinical Characteristics
Lactic dehydrogenase (LDH) deficiency may be clinically indistinguishable from phosphofructokinase deficiency. It is characterized clinically by cramps, muscle necrosis and myoglobinuria after strenuous exercise. In LDH deficiency there is no lactic acidosis but marked hyperpyruvic acidemia during the ischemic forearm exercise test (if this condition is suspected, pyruvic acid determination should be measured during the test). The diagnosis is made by measuring the LDH-M subunit in erythrocytes
Precipitants
Exercise may triger cramps and myoglobinuria.
Provocation Tests
There is no lactic acidosis but marked hyperpyruvic acidemia during the ischemic forearm exercise test (if this condition is suspected, pyruvic acid determination should be measured during the test).
Diagnostic Procedures
The diagnosis is made by measuring the LDH-M subunit in erythrocytes.