Many cancers can raise LDH levels, so LDH may be used as a tumor marker, but at the same time, it is not useful in identifying a specific kind of cancer. Measuring LDH levels can be helpful in monitoring treatment for cancer. Noncancerous conditions that can raise LDH levels include heart failure, hypothyroidism, anemia, pre-eclampsia,  meningitis, encephalitis, acute pancreatitis, HIV and lung or liver disease.
Tissue breakdown releases LDH, and therefore, LDH can be measured as a surrogate for tissue breakdown (e.g., hemolysis). LDH is measured by the lactate dehydrogenase (LDH) test (also known as the LDH test or lactic acid dehydrogenase test). Comparison of the measured LDH values with the normal range help guide diagnosis.