What is the normal level of creatine kinase isoenzyme in children

The normal value of creatine kinase isoenzyme CK-MB in children is usually 0-24U/L, and the specific value may vary depending on the detection method, age, and physiological status. The main influencing factors include the sensitivity of detection instruments, muscle injury after intense exercise, pathological conditions such as myocarditis, hemolysis interference of specimens, and congenital metabolic abnormalities.

1. Differences in detection methods:

There are differences in the results of CK-MB determination using detection equipment such as immunosuppression and electrophoresis used by different medical institutions. Some high-sensitivity instruments may set the upper limit of normal value to 16U/L, which needs to be comprehensively judged based on the reference range provided by the laboratory.

2. Exercise factors:

Intense exercise may lead to the release of small amounts of CK-MB from skeletal muscles, resulting in pseudo elevation. Children may experience transient numerical fluctuations during high-intensity running, jumping, and other activities within 48 hours before blood draw, but usually not exceeding twice the normal value.

3. Myocardial injury:

Viral myocarditis is a common pathological cause of elevated CK-MB in children, with values exceeding 50U/L, often accompanied by chest tightness and fatigue symptoms. Children with myocardial infarction may experience a sharp increase in CK-MB levels that are more than 5 times higher than normal.

4. Specimen factors:

During the blood collection process, the rupture of red blood cells can lead to hemolysis, and the released adenylate kinase may interfere with the detection results. If the specimen appears light red or the test report indicates hemolysis, it is necessary to re collect blood for re examination.

5. Metabolic disorders: In rare cases, genetic metabolic defects such as glycogen storage disorder and mitochondrial myopathy may lead to sustained mild elevation of CK-MB, often accompanied by muscle weakness, delayed motor development, and other manifestations. When parents discover abnormal CK-MB, they should avoid letting their children engage in vigorous exercise and ensure adequate rest. Daily diet can increase the intake of deep-sea fish, nuts, and other foods rich in coenzyme Q10, which can help with energy metabolism in myocardial cells. If the value remains above 30U/L or is accompanied by symptoms such as arrhythmia and pale complexion, further examinations such as electrocardiogram and echocardiography should be performed in a timely manner. It is recommended to choose the same medical institution for re examination during regular physical examinations to reduce the impact of differences in testing methods on the results.