Lactate dehydrogenase isoenzymes

Keywords: LD isoenzymes

Specimen:

5 mL blood in plain or lithium heparin tube.

Method:

Electrophoresis. Other methods are not reliable.

Reference Interval:

Consult laboratory.

Application:

Occasionally required for identification of the tissue source of increased LD.

Interpretation:

LD1 is predominant in Myocardial infarction, haemolysis, ineffective erythropoiesis (especially Megaloblastic anaemia), renal infarction, some malignancies (eg, teratoma), chronic muscle destruction (eg, Duchenne/Becker muscular dystrophy).

LD2 or LD3 predominate in malignancy, infectious mononucleosis, platelet destruction (eg, ITP).

LD5 predominates in liver and skeletal muscle disease.

See also Pleural/pericardial fluid exam and Peritoneal fluid examination.

Reference:

von Eyben FE. Clin Biochem 2001; 34(6): 441-454.