Hereditary Neuropathy with liability to Pressure Palsis
Almost two years ago my oldest daughter who was six at the time suddenly lost some of the use of her left hand. It was instant and without apparent injury.
She could not lift her her hand at the wrist, could not make a fist, could not spread her fingers and had a very weak grip. I thought she had just slept on her hand funny and that it would come back. She later told me that it had actually stopped working the night before when she was listening to her Aunt read her a story. She was doing nothing at all, just resting her head on her hands propped up on her elbows It didn't improve and upon visiting the doctor he rushed us to Primary Children's Hospital for immediate tests which all came back normal. A relief, but she was obviously not normal so the tests continued. Over several months she had X-rays, CAT scans, MRIs with and without contrast, ultrasounds, a nerve conduction test, numerous physicals, and so on. All that was determined was that she did have nerve damage and they had no idea why. We were so sick of doctors and tests with no answers and she wasn't getting any better. One symptom she did not have was pain, thankfully. There was mention of a possible genetic nerve disorder being the cause by the pediatric neurologist. She said that this disease allows the nerves to be injured more easily but I completely dismissed it. She wasn't DOING anything. How could that injure the nerves, more vulnerable or not. Plus, I had never heard of anything at all like this happening in my family or my husband in his. The only option they gave us for help was surgery on her elbow to move her nerves. My husband and I were not comfortable with this especially when it wasn't clear why or how the nerve damage occurred and requested that we try physical therapy. We were referred to a wonderful group of therapists and the actual type she received is called occupational therapy. Her therapist began aggressive treatments. We would visit several times a week at first where he taught her at home exercises to do and he would shock her muscles in the hand and arm to force contractions. She had almost complete atrophy at this point. Her progress was very slow in the beginning but once she regained some muscle her movement and ability improved very quickly and within a few more months she had complete recovery except for a small section of her arm that still has no feeling. It was bizarre but we were very thankful and thought we were done with that. Almost exactly a year after the first injury she was playing a boxing game on the wii when suddenly she lost strength in her right hand, arm, shoulder and back. I immediately took her into the therapists and he was shocked by the second injury and even more that it was with the other hand. He did some work with her but said we needed to go back to the doctors. I really didn't want her to go through all of that again but we went back to the pediatrician who sent us back to the neurologist. To my surprise, the neurologist said with almost complete certainty that it was the genetic nerve disease causing the problem. I had expected more confusion but this second injury had brought more clarity. All she needed was a blood test to confirm and we would go from there. I took down the name of the disease this time and began my own research. Unfortunately, there is not a lot of information out there and because it is so rare in the general population, most doctors have not even heard of it. This is the reason it took so long to get it diagnosed and is also the reason many people with this disease get improper treatment if any at all and will often go undiagnosed. It is rare in the general population but anyone that has it will find it very common in their family. This is because you cannot be a carrier of this disease. You either have it or you don't. If you do, there is a 50% chance that you will pass it on to each child. Since our daughter was confirmed to have this disease, it meant that either my husband or I did have it, and then one of our parents and then one of theirs, and so on, not to mention any number of extended family members that inherited it as well. I was able to find one good website with information that has just been compiled by those who also have experience with this disease hnpp.org After studying these pages I came to understand how varied in severity this disease can be and that it can affect any part of the body. I came to recognize the symptoms and once I had learned what questions to ask I began interviewing our families about their related medical history. I was amazed at how easily I was able to find those with the disease. Even my own husband's injuries, which he had had, we thought were not at all connected until we began studying about HNPP. For example, my husband had weakness in his arms when he would hold them above his head. This finally bothered him enough that he went to a doctor which referred him to a therapist. The therapist did some testing on him and was very confused by it. He said that based on where he lacked movement and strength he had all the symptoms of someone who had torn their rotary cuff except he had no pain. He gave him some exercises to do which helped and that was the end of it. An example of one of his milder symptoms is when he gets his blood pressure checked his entire arm goes numb for about five minutes. Most people who are bothered enough by an HNPP related nerve injury to see a doctor never make it far enough along to get to a neurologist, which are the only doctors that would even know to look for that as a cause. This disease is not too bad if you must have a disease. It is labeled as a nuisance disease because the injuries are usually mild in nature and the weakness is often regained over time as the nerves heal. It also doesn't usually express in children. Because our daughter has already had two "severe" injuries the neurologist suspects she has a severe case of the disease. It is not life threatening and if you know what to watch for and are careful in your activities, you can avoid a lot of injuries.
Who Has It?:
We have learned it has been passed through the Renstrom line at least as far back as Andrew Renstrom. There is even one line of cousins that is already aware of this disease and had already been tested and confirmed to have HNPP. I have not been able to trace it beyond but Andrew's grandson believes these nerve problems were common in the village he came from in Sweden.
Why Should I Watch for it?
Surgery will not help a nerve injury in someone who has HNPP and most likely will only cause more nerve damage. It is important to be aware of this family condition to potentially prevent unnecessary tests, doctors bills, surgeries and injuries.
How Does Having HNPP make nerves more susceptible to Injury?
The myelin coating that covers the nerves acts as a rubber band and coating to keep them protected and in place. With HNPP the myelin has lost its "elasticity" and once a nerve is stretched, it is left exposed and vulnerable. Normal daily activities can cause nerve injury to someone with this disease.
How Do I Prevent an HNPP Related Injury?
The nerves being extended too far, worn from repeated movement, or have too much pressure applied can cause injury. As a mother this is frustrating because it sounds like there is no way to protect my daughter. But the best way is to avoid repetitive movements by changing up what you are doing often, avoid pressure by changing how you are resting or sitting often, and avoid over stretching by not pushing your body to the limits of its ability.
I am not a doctor and am simply sharing what I have learned through our experiences with our family and from my research and our daughter's doctors. Each person will vary greatly on how their body reacts to stress placed on the nerves. If you do have this disease, get to know your limits and do not push them. I wanted to put this information out there so any possible family members that may have related symptoms can get properly diagnosed.
