Hypokalemic Periodic Paralysis

I had a couple of questions the other day about Digger's disease and I realized that I had never addressed it head-on here, just mentioned it in passing in a couple of posts.

All of my kids have an inherited disease called Hypokalemic Periodic Paralysis (HypoKPP) which they inherited from their father, who inherited it from his father, who inherited it from his father...as far back as anyone can research.

It affects 1 in 100,000 people statistically (unless you happen to inherit the lucky gene) and causes signs and symptoms ranging from periodic extremity weakness to full-on paralysis, sometimes involving the respiratory muscles.  It's what's known as an ion channelopathy, specifically affecting the sodium/potassium and calcium channels in the cells.  Potassium must be pumped out of the cell and sodium pumped in.  It's all a very complicated way to maintain homeostasis (or balance) within the body.  Calcium is the necessary ion for muscle contraction, without calcium to activate the troponin and tropomycin, which then allows the actin and myosin heads to be released, no contraction can occur.  When those channels don't work, it throws a monkey wrench into, well, pretty much everything.

In a family with HypoKPP, each offspring has the following chances or not of inheriting the disease:

• 25% will inherit the trait and will exhibit signs and symptoms
• 50% will inherit the train, but will not exhibit signs and symptoms, but may pass on the trait to their offspring
• 25% will be home free; they won't inherit the trait, won't show any signs and symptoms, and won't pass it on to their kids

I knew that my husband had the trait (and exhibited all signs and symptoms) and expected that if I had kids, they would probably have the disease.  The degree to which patients are affected varies.  For example, Digger has mornings when he wakes up a quad, but Ashinator's disease manifests itself via muscle weakness and drop attacks.  Ash tends to recover faster from attacks than Digger, who can take days to fully recover.  Monster complained of muscle weakness when he was younger, but no longer seems to exhibit any signs or symptoms.

It's much, much worse in puberty, but can be brought under control in adulthood.  Digger currently controls his with an assortment of prescription medications designed to help control his potassium balance.  Ashinator and Monster have such mild attacks, that they don't take any daily medications and will take prescription potassium only during an attack.

I worry about him living so far away with his roommates because I've seen the worst of his attacks and they're not pretty.  However, he's managing them pretty well for now.

We've developed a pretty good sense of humor about the whole thing - in fact, Digger's got about a 10 minute routine in which he re-counts the story of the day Ashinator tried to move him from his bedroom to the couch using a skateboard.  If I can get him to let me film him telling it, I'll be sure to put it up.