Avian Enzyme Profiling


A clinicians may tend to scan a blood profile and instantly conclude that any enzyme elevation suggests liver dysfunction, when in fact many incidents are non-hepatic or are of uncertain origin. Assuming no plasma quality problems (hemolysis, lipemia, bacterial contamination), the clinician can use the following guidelines:

Moderate Elevations in AST, LDH, CK- LDH elevates and declines most rapidly, followed by CK and AST. This profile points to non-hepatic cellular damage and leakage, such as skeletal muscle or cardiac muscle. This profile does not rule out partial contribution to AST and LDH elevation derived from hepatic sources.

Moderate Elevation in AST, normal LDH, normal CPK- This pattern suggests two possibilities: acute skeletal or cardiac muscle damage which occurred and ceased 2-4 days previously, or the more likely conclusion that AST contribution stems from hepatic damage.

Normal AST, High LDH, Moderate Elevation in CK- This profile suggests skeletal or cardiac muscular insult commencing less than 24 hours before sampling. Subsequent resampling in 24-48 hours might show normal LDH, slight elevation in CK, and slight-to-moderate elevation in AST.

Normal AST, High LDH, Normal CK- At this point in time, it is not possible to determine whether elevation is contributed by hepatic or cardiac/skeletal muscle. It is important to review plasma/serum quality, as the most common cause of this profile is hemolysis due to sampling or processing errors.

Elevated AST, Elevated LDH, Normal CK- This profile most likely suggests hepatocellular damage.

Normal AST, Normal LDH, Normal CK- There is no evidence of current cellular damage being contributed from the heart, muscle or liver. The clinician is unable to make any conclusion about the patient's liver function, only that no apparent damage is currently occurring.