Urology & Urogynecology > Education and Reference

A patient with a neuromuscular disease will ultimately experience an effect of the disease on his/her lower urinary tract. Sometimes the effect is a direct symptom of the disease, sometimes it is a side effect of medication. For example:

• In multiple sclerosis, plaques affect peripheral, central and cortical control of micturition. These patient’s often experience intermittent, otherwise unexplained episodes of incontinence and retention. These symptoms are usually related to detrusor-sphincter dyssynergia(2) or non-relaxing urethral sphincter obstruction(2).
• Patients with Parkinson’s disease may experience incontinence as a result of the disease process or as a side effect of the anti-Parkinson medications.
• Patient’s with spinal disraphism (e.g., spina bifida) require urodynamic evaluation at birth admission, with frequent follow-up (usually every 3 months) their first year of life and at least annually thereafter. This condition results in retention and the patients are on self-cath programs and must be monitored for upper tract damage.
• Diabetes, although considered an endocrine disorder, has a long-term neuromuscular impact. Elevated blood glucose damages peripheral innervation. If a diabetic patient is experiencing numbness of the fingers and toes, diminished sensation in the bladder is occurring as well. This peripheral denervation of the bladder results in a decrease in the perception of fullness, leading to delayed voiding and, gradually, an overstretched, poorly contractile bladder. The fact that poorly regulated diabetics tend to drink and void large amounts, compounds the problem.

A patient with diseases that have a metabolic impact, such as diabetes, cardiac and kidney disease may experience an effect of the disease on his/her lower urinary tract. Sometimes the effect is a direct symptom of the disease, sometimes it is a side effect of medication.

• As previously described, the elevated blood glucose in long-term diabetes can result in peripheral denervation of the bladder. This neuromuscular effect is compounded by increased/excessive thirst (polydipsia), high volume output (polyuria) and electrolyte imbalance.
• Patients with cardiac problems take medications that affect the neuroreceptors in the lower urinary tract. In addition, they often take diuretics.
• Patients with kidney disease are often on restricted intake, have reduced output and are prone to UTI.

The presence of an active, clinical infection in the upper or lower urinary tract is an absolute contraindication for urodynamics, other than non-instrumented Uroflowmetry. However, a urodynamic evaluation may be warranted if pain or voiding symptoms persist after the infection has been treated and resolved. See CONTRAINDICATIONS / CONSIDERATIONS on page 15 for more information.