Jan, can a person have Becker's and also have the sensitivity to cold? Things are far worse for me in the colder months. And to even think of going into a cold pool or lake makes me very anxious because I would get as stiff as a board as soon as I went in the water. But, I don't believe I have any of the other Paramyotonia symptoms. Only Becker's symptoms. I still need my DNA testing...hopefully this Fall. Thank you - Tammy
Both types of myotonia congenita are sensitive to cold. And to make it even more confusing, you can have paramyotonia without cold sensitivity. It's all dependent on the specific mutations.
I only swim in therapy pools which are close to 90 degrees. I was a lifeguard as a teenager and remember having some scary episodes with stiffness. In the cooler weather I layer clothes and keep a few packages of ThermaCare Heat Wraps in my car!
This article might be interesting to you since Nowack is a German surname. This is about a sodium channel mutation but without symptoms of paramyotonia.
Jan
Muscle Nerve. 2007 May;35(5):599-606.
A large German kindred with cold-aggravated myotonia and a heterozygous A1481D mutation in the SCN4A gene.
Schoser BG, Schröder JM, Grimm T, Sternberg D, Kress W.
Source
Friedrich Baur Institute, Department of Neurology, Ludwig Maximilians University Munich, Ziemssenstrasse 1a, 80336 Munich, and Department of Neuropathology, University Hospital, RWTH Aachen, Germany. bschoser@med.uni-muenchen.de
Abstract
Muscle sodium-channel disorders cover a spectrum of rare myotonic diseases. In a German family with 17 affected individuals in four generations, we identified a heterozygous missense mutation in exon 24 A1481D (c.4442 C>A) of the voltage-gated sodium channel gene (SCN4A) alpha subunit. Phenotypes of 12 family members were characterized by a mild myotonia with cold sensitivity but without paramyotonia. The index patient presented with fluctuating cold- and exercise-induced stiffness of ocular, facial, and distal muscles. The myotonia became more severe at the age of 22 years. His father had had cold- and exercise-induced periodic weakness with fluctuating myotonia since age 10. Later he developed a more severe, purely exercise- and cold-aggravated myotonia of arms, hands, and facial muscles. The father's mother presented with cold-induced myotonia until age 65, when progressive weakness of proximal limb muscles developed. Her muscle biopsies revealed considerable myopathic changes with a variety of fine structural alterations. This study presents a family with cold-aggravated myotonia and progression of myopathic changes in the muscle biopsy with increasing age. In older patients, sodium channelopathies may mimic the phenotypic features of myotonic dystrophy type 2.
WOW!! That's so interesting, Jan! Can't thank YOU enough! I love my maiden name. It's on my license plate too! :) I have been divorced for twenty years. I would really love to change it back. I will add this to all of my info I am gathering for my records. YOU are so appreciated! Thank you ALWAYS! - Tammy
It seems as though there really are very few constant symptoms of this disease. My Doctor was surprised that I am skinny like a toothpick and that I don't have the big bulky muscles that are described in the literature.
It does make it difficult to figure out.