Saturday, February 25, 2012

Annual Neurological Checkup

I took our oldest in for her annual exam with the Neurologist at the Children's Hospital. They did another nerve conduction test (electromyogram or EMG) on her extremities. The first time she had this done was a few years ago during all her exploratory testing to determine what was wrong with her. I was promised that she would be medicated for the test. This is a test where they put a needle into a muscle and send a shock, then they measure the response time and strength from the nerves. My daughter is very afraid of needles so I was grateful she was going to receive medication for it. My husband was able to go with her for it but when they finally set her up for the test, the doctor said that there was not enough time to administer and wait for the medication to take effect so they had to do it unmedicated. He chose to go ahead with the testing since we had waited so long to get an appointment for it. It was a very traumatic experience for her. When my husband told me about it, I was very angry about how it was handled. This was just part of my poor daughter's trial in the effort to get her mystery problems diagnosed. They wanted to get another conduction test done because it has been a few years and because their readings weren't very accurate due to her distress during the last one. The medication was a priority this time and it did go much smoother thankfully. We also had a much less in depth EMG done on our second oldest who is six to see if there were any abnormal nerve responses. There is a 50% chance that each of our children have the disease but our oldest is the only one who has expressed any symptoms and the only one tested for the disease. Testing her, our second, provides us with a base line to work from should she develop symptoms later and may show if there is any damage. It will not confirm whether she does or does not have HNPP but if there is any nerve damage, it is a possibility.
The Results:
Our oldest showed evidence of nerve damage on every nerve tested. Her arms, wrists, legs and ankles were all tested. Not good at only 9 years old but things could be worse. She appears to be functioning normally right now and her only recent issue was very mild. She woke up with one arm much weaker than the other. She could move everything as she should but it took a lot more effort. Thankfully this problem was gone by the end of the day. We have her sleeping on a memory foam mattress to reduce pressure while she sleeps but it is not a guarantee.
This disease is so hard to monitor. Nerves can and are being injured during normal daily activity but you don't know until enough of the nerves in the bundle get damaged that the others can no longer compensate for the difference. Then we see it, when normal function is effected. She had a period of over a year where she was incontinent. Her bladder muscles were very weak. Very unusual in young children who are well beyond toilet training. It only made sense to me that it was HNPP related. Muscle weakness onset with no apparent injury and then the eventual "healing" on its own. We went to several doctors about this problem too and none could agree on a cause or found something that would help. Some thought it might be related, some said it wasn't, and no one said it was for sure due to HNPP. Another trial in having a rare, lesser studied and lesser known disease.
Our second child's results were that she did have some nerve damage in her wrists. Similar to carpal tunnel at six years old. Not normal but not a confirmation that she has it, probably does in my opinion.
I understand genetically how each of our children have a 50% chance of having this disease. It is not one that can be a recessive gene, you cannot be a carrier. You either have the needed gene(PMP22) or you don't. Normal individuals have two PMP22 genes. This gene affects the myelin coating or sheath surrounding and protecting the nerves. Those with CMT have more than two, those with HNPP are missing one. The non affected parent gives one PMP22 gene, and the other parent has a 50% chance of giving the gene or not giving it. Thus there is a 50% chance that you will get that needed second gene. If you don't get it, you have HNPP. This being said, there seems to be a much higher percentage in my husband's family. His father, who has been tested and confirmed to have HNPP, had four children. All four show symptoms of HNPP. Of these four, two of them had children. The oldest children in these two families thus far have expressed symptoms of HNPP.
In My Opinion: It seems to be difficult for doctors to accept unusual symptoms from HNPP patients being due to HNPP. Not only is it rare, it is also rarely diagnosed due to its hugely varied symptomatology, varied degree of severity and lack of knowledge among the medical community. My husband visited several doctors over the years for various problems that were considered "mysterious" in some way and not only was the condition HNPP not considered, it was completely unknown to them. He was never led to a neurologist and there are many others with mild enough symptoms that they never mention them to a doctor. We were only led to the knowledge of it in our family through our daughter's problems, and even then I feel we were lucky we received the correct diagnosis despite it taking a year. Her neurologist was familiar with it. Even with this knowledge we hit stumbling blocks with doctors who just don't know enough about it to accept what we say. They still want to eliminate all other possibilities for having the trouble they do before reaching the conclusion that the only thing you can do is leave it alone until it starts to heal and then mild occupational or physical therapy to regain as much movement as you can. I appreciate doctors and all they are able to do but they are also part of a frustrating cycle at times. Hopefully in years to come it will get better as more information becomes available to all of us.