My 13 yr old son

My son is turning 13. He was diagnosed with Spastic Diplegic Cerebral Palsy. As i watch his muscles deteriorate slowly i became concerned of Muscular Dystrophy (runs high in my family). Things he was able to do before, he can't do anymore. I had his PCP run labs on him (CPK's) and CK-MM was 97, CK-MB was 0, but his CK-BB was a 4 and marked "high" on the lab sheet. His dr called me and said that it was elevated only because he had surgery on his Subclavian artery 3 yrs ago and they cancelled his muscle biopsy saying there was no signs of MD. I looked up on the internet and CC-BB had nothing to do with arteries etc. but says "if high, could be Sclerosing bone disease, blood clots in lungs or lung disease". What is actually going on with my son since we are not getting appropriate answers from PCP? Can you please explain? I am losing sleep over this and im scared for him.

[Neuro Forum]

Thanks for using the forum. I am happy to address your questions, and my answer will be based on the information you provided here. Please make sure you recognize that this forum is for educational purposes only, and it does not substitute for a formal office visit with your doctor.

Without the ability to examine your son and obtain a history, I can not tell you what the exact cause of his symptoms is. However I will try to provide you with some useful information.

Spastic diplegia is diagnosed based on examination findings of spasticity, or increased tone in the legs, with or without weakness, that occurs with injury to the brain from various reasons, and is broadly diagnosed as cerebral palsy. If there is significant brain injury leading to leg weakness, atrophy of the muscles occurs over time. Loss of function can occur due to weakness, but also, progressing spasticity. Therefore, if a child with a [correct] diagnosis of cerebral palsy loses milestones (loses ability to do the things he used to do), possibilities include worsening spasticity or addition of dystonia, a type of abnormal muscle contraction that can start later on in the course of cerebral palsy.

Muscle atrophy in the legs does occur in muscular dystrophy, but spasticity is absent in muscular dystrophy; therefore, this is one of several other physical examination findings that help distinguish the two disorders. In other words, based on the history and based on physical examination, the two disorders are therefore distinguishable by an experienced physician. In muscular dystrophy, the CK-MM isozyme is the form that is elevated. An elevated CK BB level is nonspecific: its elevation can be due to various causes, that do not necessarily portend a worrisome process occuring. CK-BB is not found in skeletal muscle (the muscles of the arms and legs) therefore, its source would be some other tissue (brain or smooth muscle or a few others). While there are some conditions that cause elevated CK-BB, in general, it is not used as a test for any specific disorders because it is again nonspecific.

If your son is losing ability to do the things he once did, it is not unreasonable to reassess his diagnosis of cerebral palsy or to see if there is something else going on, but it is important to understand that patients with cerebral palsy can worsen over time, whether due to worsening spasticity or new types of movement such as dystonia. Evaluation by a pediatric neurologist is recommended, as if his loss of certain skills is due to the latter, this could be treatable with a combination of medications and physical therapy; the pediatric neurologist will also be able to answer your questions about whether or not there is evidence that should raise concern for another disorder such as muscular dystrophy or something else.

Thank you for this opportunity to answer your questions, I hope you find the information I have provided useful, good luck.

[Marcus06]

A related discussion, What is causing my high CK-BB level was started.