Urinary Retention: CNS or Local Problem?

[Erica__0]

  I have had approx. 5 episodes of bladder discomfort within the past 18 mos. Have never had bladder pain or UTIs before. Was seen  3 times and told I did not have a bladder infection (after urine cultures/tests were complete). Muscle problem was mentioned.
  This past June, I experienced a neuro-like attack of leg weakness/internal vibration in lower legs, feet and hands. Pins
  needles feeling in left foot, involuntary left leg movement while at rest, and extreme all-over fatigue.
  Before I stabilized, bladder discomfort began again; however, this time I had chronic problems starting stream and finishing, and had to bear down in order to complete voiding. Twice I could not void at all--once after exercise and once upon awakening in AM.
  I was diagnosed with Myasthenia Gravis in 1994. My MG neuro referred me to a urologist for testing last month. Urologist was to determine if I had local or CNS bladder disorder (my understanding).
  After testing, urol referred me to MS specialist because urol felt I had CNS difficulty. (He ruled out local problem.)
  During testing, 4-5 oz. urine was drained from bladder after I finished voiding.
  MS specialist said I did not have MS or a CNS bladder...thru clinical testing. However, he agreed to request MRI of brain with gadolinium. Don't have results yet.
  Urologist put me on Flomax and it has helped. I had to catheterize until urine retention was less than 2 oz. Urol disagrees with MS neuro and maintains that I have CNS problem with bladder. He is happy that Flomax works and is taking a wait and see attitude.
  1. What are examples of "local" causes of urinary retention? [that were ruled out]
  2. Can a local problem mimic a central problem?
  3. If I do not have MS, what other CNS disorder would cause urinary retention and hesitancy?
  4. If MRI is negative, it still does not rule out MS because I could have hidden lesions (my understanding). So, can my
  bladder continue to deteriorate because an "unknown cause" exists?
  5. If I did have MS and was not diagnosed or put on appropriate meds, wouldn't nerve fibers eventually  destroy and cause permanent damage to bladder?
  I appreciate any comments or suggestions....Thanks.

[hfhs M.D.-AK]

Dear Erica,
You ask alot of very difficult and controversial questions.  It would be important to know the diagnosis of your condition such that you could be managed appropriately from a neurologic point of view.  It is true a small number patients have their  diagnosis made of MS due to the presenting symptom of bladder dysfunction, but usually the gold standard is identification of plaques in the CNS.  I will discuss the symptoms and the physiology of MS as it is associated to bladder dysfunction and also for MG.
I will be very general in my answer and will attempt to answer all of your question in a manner not to raise unnecessary worrying on your part.  Normal bladder function is dependent on both an intact nervous system(sensory and motor) as well as anatomic capabilities(physiologic function).  Any disruption of the CNS or anatomic problem may cause bladder dysfunction.  This means any neurologic disease, medical disease that affects sensation, or infectious disease that affect motor control could be the source of your problem.  Both central CNS disorders often have similar signs and symptoms of local disease.  I don’t know what work-up was performed by your urologist to rule out any certain conditions, but the approach your urologist has taken is just how I would approach your problems.  I would establish goals and treat your symptoms to the best of modern day medicines ability.
MS is one of the most common neurologic diseases causing voiding dysfunction.  The disease is caused by impairment of the conduction nerves involved in the function of the bladder.  50-88% of patients with this disease complain of some type of urinary tract dysfunction at some time during their disease process.  Bladder involvement is part of the presenting symptoms in approximately 10% of patients.  The primary urologic findings include, an overactive bladder which squeezes when it is not supposed to, a nonfunctioning (atonic) bladder that cannot squeeze at all, and a bladder that can squeeze but the sphincter or valve to empty the bladder won’t open properly.  The diagnosis is made by identifying plaques in the brain stem and spinal cord.  You are correct that these lesions are not always visible on MRI or CT scan.  The neurologic deterioration of the myelin in MS will occur no matter what medications you are on.  The best way to manage your urological problems is to take care of your symptoms.
For  myasthenia gravis there can also be dysfunction of clinical urologic significance.  As you know, MG is an autoimmune disease with antibodies against the nicotinic receptors.  This results in the diminished contractile force and marked fatigue of all structure with nicotinic receptors.  The bladder is one of these structures.  Therefore, the bladder muscle can become fatigued and not provide the force for complete emptying as in your case.
Your urologist has treated you with Flomax one of the alpha blockers.  It sounds like this medicine is working for you.  This medication often reduces the outlet resistance at the bladder neck thus making it easier for you to void at low pressures.  Of note, however, is that this medicine is not approved for this purpose in women.
Overall the goal for your urologists is to protect your kidneys from deterioration.  In time your bladder dysfunction may become critical and medical as well as surgical intervention may be necessary.
A patient in your situation with history of high post void residuals can always be managed with intermittent catheterization which you have already had some success with.  It will be important that you continue to follow-up with your urologist in the future such that all necessary urodynamic and emptying studies can be completed to manage you appropriately.
I don’t want to make a list of scary neurologic diseases that can be associated with bladder dysfunction because I don’t think it would be of any benefit for you to try and diagnose yourself.  I think you are in good hands with your current doctors and should follow their suggestions.  I wish you luck with you bladder management and a formal diagnosis.
This information is provided for general medical educational purposes only.  Please consult your physician for diagnostic and treatment options pertaining to your specific medical condition.  More individualized care is available at the Henry Ford Hospital and its satellites (1 800 653-6568).
Sincerely,
HFHS M.D.-AK
*keyword:Bladder Dysfunction.

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