Alternative Names for Lactate Dehydrogenase
Lactate dehydrogenase (LDH) is also known as lactic acid dehydrogenase, and the test may be ordered simply as "LDH" or "total LDH" in clinical practice. 1, 2
Common Terminology and Abbreviations
LDH is the standard abbreviation used universally in clinical laboratories and medical literature 3, 4, 1, 4, 5, 2
Lactic acid dehydrogenase is the full alternative name, though "lactate dehydrogenase" is more biochemically accurate since the enzyme catalyzes the reversible conversion of lactate (not lactic acid) to pyruvate 6, 7
The enzyme may be referred to by its EC number: EC 1.1.1.27 in biochemical contexts 7
Clinical Laboratory Ordering
When ordering this test, you may encounter:
Total LDH - measures overall enzyme activity from all tissue sources 1, 7
LDH isoenzymes or LDH fractions - when specific tissue origin needs to be determined, though this is less commonly ordered 1, 6
Serum LDH or plasma LDH - specifying the sample type 3
Important Clinical Context
The test measures enzymatic activity through spectrophotometric methods that monitor the conversion of lactate to pyruvate (or vice versa) with NAD+/NADH as coenzyme 1, 7. LDH is widely used as a nonspecific marker of tissue damage and cell death, with clinical applications in pleural effusion analysis, cancer prognosis, and various inflammatory conditions 3, 4, 2, 8. The upper limit of normal is highly laboratory-specific and depends on assay conditions 1, 2.