Myasthenia Gravis or a brain tumor?

[milesmom]

The doctors think that my 4 yr old either has myasthenia gravis or a brain tumor.  His eyes stopped working together suddenly and he was diagnosed with 4th cranial nerve palsy by the eye doctor who says that it is caused by his epilepsy.  His neuorologist does not think it is caused by his seizures says that it is 6th cranial nerve palsy.  He also says that it is possibly caused by either myasthenia gravis or a brain tumor.  My pediatrician says that myasthenia gravis is very rare for a child his age and she isn't sure what testing can be done to diagnose.  She spoke of the tensilon test but needs to do some research to see if he is too young to do that test on.  We have been unable to do an MRI because his reactive airway disease is pretty active right now and sedation isn't that safe at this point.  (we are treating with oral steroids, an antibiotic plus his normal breathing treatments).

His most noticable symptom is his eyes - his left eye turns very far in and up, gets stuck from time to time, he tilts his head to see clearly, sees double from time to time when his head is not tilted, and complains of pain in his left eye.  However, everyday he complains of his legs, hands, feet and arms being tired.  I am not sure if that is behavioral, caused by fatigue due to his respiratory issues or even complications from his heart defect (tetralogy of fallot w/pulmonary atresia repaired).  He has a difficult time walking long distances but seems to play very well on the playground in spurts.

His epilpesy is pretty bad but currently well controlled on almost 1000mg of trileptal a day and is not currently (or when the eye stuff started) experiencing any seizure activity that we are aware of.  

Any info, insight, feedback would be greatly appreciated!

[sofa weight]

Has your son had an MRI? the tumor could most likely be ruled out using the MRI. Also, in addition to the post provided by the other member who responded to your question, there is also a kind of EMG they can do that tests for responses given repeated stimulation. I can't remember the name of it. But, basically, they do electrical stimulation over and over and check to see the amt of fatigue.. or the decrease of response at the neuromuscular junction.. either that or I have totally babbled out of control. I looked it up and it said the same thing that I said. :) ok. i'll just say it is a repetitive nerve stimulation test.  The drug that you said that your son is on can cause both the double vision, his eye going off in the wrong direction, and also, although it would be rare, a decrease in the amt of sodium in his body, which could explain the fatigue that he is experiencing when playing for long periods of time on the playground. I am of course, not saying that he doesn't have myesthenia gravis because I have no clue. I am just sharing the info that I have. I think that primarily, your son needs an MRI if he hasn't had one already. He probably was given one though in order to diagnose his epilepsy or at least to rule out a mass as the cause for the epilepsy. Also, I think that an electrolyte test would be in order. That would be the fastest, easiest, and cheapest test to have so would probably be the one that I would choose first. The EMG would need to be done if the electrolyte test, the aChR test and the MRI are normal. I hope that this was helpful. Most probably his neurologist would suggest the same stuff though. but i know that there is always the period of unease in between appointments.

[doublevision1]

There is a blood test that detects the presence of acetylcholine receptor antibodies in patients with MG.  It is a very useful test, however about half of patients will test negative if they have only the ocular form of this disease.  Your son's symptoms of diplopia and muscle fatigue/weakness do sound consistent with MG, unfortunately these symptoms can be caused by so many other neurological conditions that it may take a while to figure it out.  I would think that the blood test for MG would be the next logical step.  I've heard of the Tensilon test but as I understand it, this is done only after the blood test is inconclusive.

There is some good info on MG at:
www. ninds. nih. gov/ disorders / myasthenia _ gravis / detail _ myasthenia _ gravis . htm

(note: you'll need to delete all the spaces I inserted in the above URL, in order to connect to that webpage)


BTW, I had suspected MG last year when I experienced double vision very similar to what you are describing in your son.  I also had lots of numbness, neuropathic pain, dizziness and fatigue.  The blood test for MG was done, results came back quickly and were normal.  Turned out what I have is MS, as revealed by my symptoms and lesions on my brain and spine detected by MRI.  I would not think this is the case with your son.  Although MS can happen in young children, it is very very rare, much more so than MG as I understand it.

I'm sorry your family is going through this, and I hope you find answers and the appropriate treatment soon.

Peace.

~doublevision1~