CPK Level Abnormal (18,000)

I'm a 40 y.o. white male in good health. I went to my doctor for chest pain and difficulty catching my breath. My heart rate at rest was about 115 (normal for me =75). Blood pressure was bouncing around from 180/110 to 122/64. I had assumed that my chest pain was due to an upper respitory issue since I had been congested for a few days. My doctor ran some blood work and became alarmed when my CPK came back at 18,000. She wanted to admit me for more test; however, I did not want to stay so I made arrangements to come back the following day for more test. The following day my CPK came down to 16,000. EMG was normal. EKG normal. All other blood test were normal. No kidney issues. No muscle soreness. No stiffness. on the 5th day my CPK was down to 1,000. My chest was feeling much better. Blood pressure was normal. Heart rate was normal (actually slightly better than normal for me). I was feeling much much better with no treatment. Now they want to do a muscle biopsy. Do you think this is necessary? What do you think could cause a CPK to jump this high?

[DrNoopurMD]

Hi,

Thanks for writing in.
CPK is an enzyme that is present inside the muscles. When muscle cells are damaged CPK is released in to the blood. Elevated CPK levels indicate Myositis or inflammation of muscles, medications, trauma, alcohol, viral infections or genetic problems with the muscles.
There are found in the heart muscles, skeletal muscles and brain cells. CPK-MB is found in the heart muscles and is elevated in viral myocarditis or heart attack.
It is only after clinical evaluations can one say, if the muscle biopsy is required or not.