The activity of LDH is often measured in clinical settings as a marker for tissue damage or disease. Elevated levels of LDH in blood serum can indicate conditions such as myocardial infarction, liver disease, and certain types of cancer. The specific isoform pattern can provide insights into the affected tissue. For example, an increase in LDH-1 is often associated with cardiac damage, while a rise in LDH-5 may indicate hepatic or muscle injury.