Lactate dehydrogenase (LDH) isoenzyme pattern LDH1 > LDH2 (flipped pattern) is characteristic of:

• A Pulmonary embolism
• B Megaloblastic anaemia only
• C Hepatocellular carcinoma
• D Acute myocardial infarction ✓

Explanation

The 'flipped LDH pattern' where LDH1 exceeds LDH2 occurs in acute myocardial infarction because the heart is rich in LDH1 (H4 tetramer). Normally LDH2 > LDH1. Pulmonary embolism raises LDH3. Megaloblastic anaemia can also show a flipped pattern due to haemolysis, but the classic teaching association is with MI. Hepatic disease raises LDH5.

Reference: Harper's Illustrated Biochemistry, 32nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.