Questions & Answers
McArdle’s Disease Questions and Answers
What is McArdle’s disease?
McArdle’s disease is a metabolic disease of skeletal muscle. Humans need the enzyme muscle phosphorylase to convert glycogen to glucose within cells during physical activity. In McArdle’s disease, this enzyme is either missing or non-functional. The result of this inability to metabolize glycogen properly is premature muscle fatigue and risk of muscle injury.
How many people have McArdle’s disease?
It is estimated that McArdle’s disease affects 1 in 100,000 individuals. However, since the disease remains undiagnosed in many people until they reach adulthood, that number may be higher.
What is glycogen?
Glycogen is a storage polymer of glucose. Muscles store glucose as glycogen in order to have immediate access to an abundant energy source during exercise. Glycogen is replenished within the cell after it is depleted, which only occurs after hours of physical activity like running. Marathon runners and athletes often consume large amounts of carbohydrates the day before an event in a practice known as “carbo loading,” intended to increase the muscles’ stores of glycogen and extend performance.
Is McArdle’s disease life-threatening?
McArdle’s disease is not by itself life-threatening, but muscle failure itself can be hazardous in a number of ways. Strenuous activities depend on glycogen metabolism, and without the energy to sustain such activities people with McArdle’s disease may find themselves unable to finish what they have started. While swimming, chewing and swallowing food, an episode of muscle failure can be disastrous. People with McArdle’s disease should always remain aware of their limitations to avoid danger.
Is there a cure for McArdle’s disease?
There is no known cure for McArdle’s disease. A number of genetic mutations responsible for non-functioning or missing phosphorylase enzyme have been identified. To date, gene replacement therapies have not advanced beyond the experimental stage in animals.
How is McArdle’s disease treated?
Because the muscle injury that can occur with McArdle’s disease releases large amounts of protein into the blood, it can cause renal dysfunction and therefore demands medical attention. Such injuries, known as rhabdomyolysis, may be treated with intravenous saline. Refer to your physician for recommendations on treatment or if you have McArdle’s disease and want to take a pain relief medication. By avoiding such injuries and participating in a good diet and regular low-impact aerobic activity such as walking – with careful warmup periods – people with McArdle’s disease can remain quite healthy. Otherwise, there remains no consensus therapy for McArdle’s disease beyond diet and lifestyle management.
Im interested in a wonderful man who told me he has this disease. I was wondering if our sex life would be the same as that of any other couple, and if not, what I should expect.
Jennifer, While at 72, I may not be the perfect responder, I can
tell you that wonderful man has shared a fact that many put on
a back burner. In fact, it would be ideal if we knew more about
the extent of his condition. In any case, have you taken long walks with
him, danced for a few dances, been swimming or exercised together?
If you have, without him being too tired, your sex life should
be just fine. Foreplay is always a good thing in any sexual relationship, but sometimes more important for the “M” person as
a long and strenous sex act without a climax can be too tiring and
result in an involuntary need to stop for awhile and rest. Jim Ottesen
Jennifer I am 21 and have ‘m’ as far as my sex life goes if he has the energy and strength there should’nt be a problem. But sometimes he might need to rest or maybe you could just do the work more often. Sometimes my husband gets frustrated because he has to do most of the work but he understands. The more you know and the more you understand about the condition the easier the issues will be to deal with. And try to be as supportive as possible the more support you give him the less anxiety to perform there will be. And just be ok when he needs to rest. I’m possitive that if your supporitve and understand the need to rest it will be great. And remember it wont happen every time.
Rebecca, You mentioned you have “m”, but you told us you have never
seen a neurologist, did your rheumatologist do the diagnosis? How did he
make the diagnosis – what technique? Ischemic forearm, leg biopsy or
blood test? I am concerned your situation might be complicated by
other issues and feel a board certified neurologist with a speciality
in neuromuscular diseases is essential to confirm your diagnosis. I
know you are having a time finding one, but keep trying, it’s very
important. Good luck! Jim Ottesen
My 17 yr old son Robert was just diagnosed with M with thigh biopsy by a neurologist BUT many of his symptoms do not match. He does not have fatigue, cramps, or “blasting” during exercise, he has had uncontrolled muscle weakness the next day. Last summer his legs collasped he fell hit his head went to ER found very low K (2.4) and later high CK 12,000 after hard physical work for a week at Boy Scout camp. The next month after football camp, no symptoms of muscle cramps or fatigue but CK of 14,000. The next week went to nephrologist CK 1100 urine and blood clean otherwise. No myglobulin in urine. First neurologist normal EMG. Started wrestling, woke up with weak arms, CK 10,000. Last nuero said no military, easy exercise, high protein diet, diet pop not regular, no sugary drinks, need genetic test to confirm M. Should we seek 2nd opinion? Should he eat more carbs? Could it be a milder form of M without exercise induced fatigue and cramps or myoglobulin in urine?
Diane,
Yes! Your son sounds very much like he has McArdle’s Disease. The normal
for CPK is like 50 to 250. 12000 is very bad and your son could suffer
acute kidney failure if muscle stress and hard work contine to cause high CPK readings. Forget the EMG readings as they mean almost nothing
where McArdle’s Disease is concerned. While there are milder “forms”
of “M”, they can all result in serious results if not carefully monitored. I have posted many effective tools to help live with “M” so
I encourage you to read them to help guide Robert. Whey protein, lots
of vegetables, fruits, 6 to 8 glasses of water and a greens formula will
help. L-Carnitine (to 500mg) and B-6 (to 100 mg) help a great deal. If
you want to send me a copy of his biopsy, I will review it. I am not a
doctor, but at 72 and having “M” since birth I know too much about lab
tests. My e-mail is jott440148@aol.com. I also suggest the ischemic
forearm test and the genetic blood test to confirm McArdles. Periodic
blood and urine tests are appropriate and, unless Robert has high glucose readings, I wonder why he would be restricted to diet colas.
At this time, Robert should not be in competitive sports, he should
never go in the military and a light exercise program is in order.
As to a second opinion, if you can find a neuromuscular doctor specializing with afflicted patients (like one with the MDA) it would be
a good idea for the tests I have mentioned above. Robert may be in some
expected denial of his fatigue, and cramps often happen later in the
evening. I would suggest hemasticks to test the urine for blood if
the CPK continues high. I hope this helps, but let me know if I can do more. My best wishes to you an Robert. Jim
@Diane Partridge
Diane,
Any news? There is a non-ischemic forearm test that is being successfully used to confirm the biopsy and it is virtually
pain-free. I also suggest a DNA or genetics test for your son. I
really feel more clarity is essential. I suggested a second opinion
through MDA or another neurologist that deals regularly with
neuromuscular testing procedures and afflicted patients.
There are so many things that could be a problem. You must
try to remove any ambiguity.
Good luck to you! Please let us know if we can help.
Jim
We are waiting for pre-authorization from insurance company for genetic testing. After reading your great info, I looked some more, the neurologist who diagnosed Robert is a co-director of local MDA clinic in Portland. He did say research was inconclusive, but B6 and creatine could help. He also said lots of fruits and vegetables. We have started Robert on B6, whey protein, and he was told to drink lots of water, enough that he has to pee every 2 hours. Robert is determined to wrestle, his is a very small school, his coach says its up to him. So he has agreed to drink lots of water, eat a granola bar 30 minutes prior to practice, and take it easy. To be clear, he has NO cramps or muscle burning at any time, he just has the high CK counts, and has woken up with weak legs or arms 3 times in the last six months. His urine and kidneys tested clean. He has normal glucose readings. He is musclular and athletic. It sounds like the challenge will be for him to balance his exercise to stay fit and not bring on symptoms of Mcardles. I have requested copies of his biopsy and blood tests from OHSU but am waiting. When I get them I will forward to you. I will ask the nreurologist about ischemic forearm test, but he said the biopsy was very clearly showing Mcardles. I will ask about hemasticks and periodic CK tests. If you have any advice on where to go to design exercise programs, monitoring (frequency of hemasticks and CK test), and diet let me know. We do know the dietician at our local hospital. We have a good physical therapy clinic locally. Thanks again for a most excellent site, it is very valuable. We greatly appreciate it.
Diane,
I am glad we can help. If Robert does not have pain, does not tire
on exertion, does not suffer leg cramping, his level of McArdle’s is
not as serious as most. Having said that, remember that the disease
can progress in some people and acute kidney failure is always a risk.
He must always be aware that darker urine as much as 48 hours after
muscle stress is not a good sign and warrants a hemastick test. As additional precautions, blood tests(for CPK, etc.), urine tests for
blood and protein every quarter during competition is prudent. As
for an exercise program, the focus is on aerobic – not anaerobic.
Cardiovascular versus heavy weights. While not essential, the results of the
Non-ischemic forearm test and genetic tests should help to confirm
the seriousness of Robert’s disease. The dietician can help a great
deal with an analysis of percentages of carbs and protein and which
supplements might help. However, she must do her homework before she
offers any suggestions. We do not want to create problems from food.
A carefully selected personal trainer who knows – and will respect -
the risk of muscle strain can be of great value, but must be monitored.
Physical therapy is not indicated unless we have severe muscle strains
or pulls. I am still concerned over the fact that Robert has woken up
with weak arms and/or legs in the last six months – those days would
be perfect to use the hemastick and/or check the CPK. Remember, “M”
can literally destroy muscle tissue and that same tissue can clog the kidneys
so caution is uppermost for the McArdle’s athlete. Please keep me informed as to your doctor’s thoughts, the tests and progress.
I hope this helps. Let me know. Best wishes, Jim
@Jim Ottesen
Hello Jim,
My name is Brenda and I am a 45 year old female from Ontario, Canada. I was diagnosed with McArdles 9 years ago, and 6 years ago Type 1 Diabetes. The diabetes has sure made the McArdles much harder to manage as they are both battling each other, one cannot use the carbs, the other needs the carbs. Have you encountered any other patients with both diseases such as mine together? I ended up in emergency with a very, very high sugar level 6 years ago, almost to the diabetic ketoacidosis stage, and a intern was very excited to talk to me about the McArdles, he has just read an article in the New England Journal of Medicine. I guess I am a bit of a freak of nature to have two completely different channeling diseases which both affect the pancreas. I would love to hear back from you or anyone else who is a double disease sufferer such as myself. Thank you.
Hi JIm-
Just an update on Robert. Thanks again for all you are doing for patients with Mcardles. The good news is no pre-authorization is needed for genetic testing and they can use the muscle tissue from the biopsy, results in about a month. The less than good news is Robert tried light workouts the past couple of days, no cramps or muscle pain except what sounds like lactic acid buildup, but colored urine this morning (light coffee color) so no workout and lots of water today. He has upped his water intake, is taking B6 and whey protein. His CPK was measured the day he woke up with weak legs (last July) and it was 12,000 (196 high end normal) and one of the days he woke up with weak arms (this November), the first lab measured it at 222,200 which stills seems unbelievable, so a day later I took him to the other blood lab in town and it measured 9,900 still high but not as gut wrenching. The lowest it has been measured was in between (August) a week after football camp ended it was 1,100 (no weakness no pain). The article at nature.com titled “Mcardles disease: what do neurologists need to know?” talks about moderate aerobic exercise being good, and that serum CK levels decrease with training, they cite an article in the Clinical Journal of Sports Medicine 17:297-303 (2007). Because Robert’s pain/exercise tolerance symptoms are mild, he would really like to stay fit and active as much as possible. We just need to figure out how to do that. I am having the biopsy test results sent to our local doctor, and will set up a follow up appointment with him. Thanks again.
@Brenda Krushnisky
Hi Brenda,
I, too, have the pre-diabetes problem and McArdle’s. I do the best I can to avoid sugar, reduce carbs and add protein, exercise as often as possible, take B-6 (to 100mg), a strong multi-vitamin (Theragran M),
20 to 30 grams of whey or egg protein, a good greens formula and lots
of water. If one has a weight issue, try to get rid of the problem. Avoid muscle stress, focus on cardiovascular exercise, have your urine
and CK checked any time you feel overly tired or feel too much muscle
pain or at least twice a year and make sure you have an excellent internist for follow-up.
Diabetes is your biggest problem – do all you can to beat back that
problem. “M” is a big pain, but if you protect your muscles, you protect
your kidneys. Don’t lift heavey “stuff” and don’t overdo anything.
I hope this helps you out. Let me know if I can do more.
Pray for the folks in Haiti.
God bless,
Jim
@Diane Partridge
Diane,
Great news on the OK for genetic testing to confirm any doubt about
about McArdle’s Disease. However, I remain concerned about Robert’s
coffee/coke colored urine. You need to get as soon as possible
hemasticks to check for blood in the urine if he has the darker colored
urine. If a bad reading, you will need the blood tests (for CK, etc)
and urine (for blood and protein,etc.).
Yes, moderate, aerobic exercise is great, but often others translate
that to muscle building and I feel that could be harmful to Robert.
LIGHT weights, recumbent cycle, treadmill, rowing machine and exercycle
are OK in moderation. Until we have Robert’s “M” confirmation, we must
go slow. We want him to stay fit, but too much muscle deterioration
in the kidneys can result in acute kidney failure.
As a suggestion, I would suggest you maintain a graph of Robert’s activity 48 hours prior to a urine and CK test to evaluate the effect
of just how much the CK goes up as a relationship to activity. I would
also check with your doctor, neurologist or nephrologist to see at what
level would they consider a CK, urine, or other response as a danger to Robert’s kidneys. Then, I would ask for their honest opinion if Robert
is approved for wrestling, weights and moderate exercise.
At the moment, Robert (thanks to you) is eating, drinking and taking the
right vitamins and supplements. Let’s hope the news gets better and
better. I pray Robert improves, he can do the wrestling and moderate
exercise without any problem. By the way, my son’s name is Robert.
Please pray for the folks in Haiti.
Best personal regards,
Jim