A 70-year-old man comes to the physician complaining of 4-6 months of almost continuous urinary dribbling. It occurs during the day and at night and is progressively worsening. He has no dysuria or hematuria. The patient has a 20-year history of type 2 diabetes, hypertension, alcoholic hepatitis, and coronary artery disease. He had a gastric emptying study done a few weeks ago due to continuous nausea and early satiety. He had laser photocoagulation of both eyes for diabetic retinopathy. The patient has a 50-pack-year smoking history and drinks 4-6 beers daily. His medications include insulin glargine, lispro insulin, metformin, aspirin, metoprolol, lisinopril, and erythromycin. Physical examination shows a normal-size prostate, decreased sensation in both legs below the knees, and absent Achilles tendon and knee reflexes bilaterally. Postvoid residual volume is 550 mL. Urinalysis results are as follows:
Which of the following is the most likely cause of this patient's incontinence?

Question

A 70-year-old man comes to the physician complaining of 4-6 months of almost continuous urinary dribbling.  It occurs during the day and at night and is progressively worsening.  He has no dysuria or hematuria.  The patient has a 20-year history of type 2 diabetes, hypertension, alcoholic hepatitis, and coronary artery disease.  He had a gastric emptying study done a few weeks ago due to continuous nausea and early satiety.  He had laser photocoagulation of both eyes for diabetic retinopathy.  The patient has a 50-pack-year smoking history and drinks 4-6 beers daily.  His medications include insulin glargine, lispro insulin, metformin, aspirin, metoprolol, lisinopril, and erythromycin.  Physical examination shows a normal-size prostate, decreased sensation in both legs below the knees, and absent Achilles tendon and knee reflexes bilaterally.  Postvoid residual volume is 550 mL. Urinalysis results are as follows:
 Which of the following is the most likely cause of this patient's incontinence?

Quizplus · Accepted Answer

11ec25c8_d114_a2fe_bc81_6dbbea54e966_MD0003_00 This patient's presentation is consistent with likely diabetic autonomic neuropathy (DAN) affecting the genitourinary tract. Risk factors for DAN include poor glucose control and other vascular risk factors (eg, hypertension, elevated triglycerides, smoking, obesity). This patient's microvascular complications (peripheral neuropathy, retinopathy, and nephropathy) indicate poorly controlled diabetes. Parasympathetic innervation of the bladder regulates detrusor muscle contraction and internal sphincter relaxation to allow for voiding urine. DAN can cause a neurogenic bladder with decreased ability to sense a full bladder, incomplete emptying, urinary retention, and distended bladder. Patients with a higher bladder than urethral pressure develop overflow incontinence and lose urine until the pressures equalize. The symptoms can occur cyclically both day and night. Physical examination may show a distended bladder with high post-void residual urine volume (>50 mL). (Choice A) This patient's urinalysis showing proteinuria suggests glomerular disease due to diabetic nephropathy. However, diabetic nephropathy does not typically cause urinary incontinence. (Choice C) Medications (eg, anticholinergics, antipsychotics, tricyclic antidepressants, sedative-hypnotics) can block the parasympathetic pathways that initiate micturition and lead to overflow incontinence. However, this patient's current medications are not usually associated with incontinence. (Choice D) Bladder outlet obstruction due to an enlarged prostate is the most common cause of overflow incontinence in men. This patient's normal prostate exam makes this less likely than a neurogenic cause, especially in the setting of retinopathy, neuropathy and nephropathy. (Choice E) Pelvic floor weakness commonly causes stress incontinence in women. Patients develop incontinence due to increased intraabdominal pressure after coughing or sneezing. Stress incontinence can occur in older men after a radical or transurethral prostatectomy. However, patients with this condition usually have normal post-void residual volume. (Choice F) Urethral instability refers to involuntary fluctuations in the urethral pressure with or without urinary incontinence. This can occur even in normal individuals. However, it usually does not cause urinary retention or a high post-void residual volume. (Choice G) Urinary diverticulum is an outpouching of the bladder or urethra into the adjacent tissues. It is more common in women than men. Patients usually develop post-void dribbling, dysuria, and dyspareunia. The urinary stasis can lead to possible recurrent cystitis/urinary tract infection but does not cause a high post-void residual volume. (Choice H) Urinary fistula is a communication between the urethra/bladder and uterus or vagina. It occurs more commonly in women after pelvic surgery. Patients develop continuous leakage of urine without significant urinary retention. (Choice I) Urinary tract infection may cause incontinence without typical dysuria in patients with neuropathy, but patients will still have an abnormal urinalysis (eg, pyuria, positive nitrite/leukocyte esterase) and sometimes systemic symptoms (eg fever, chills). Educational objective: Diabetic autonomic neuropathy can affect the genitourinary tract to cause a neurogenic bladder with urinary retention and distended bladder. Patients can then develop overflow incontinence (eg, dribbling, poor urinary stream) with a high post-void residual volume. References: Bladder dysfunction in diabetes mellitus. (http://www.ncbi.nlm.nih.gov/pubmed/21833175)

A 70-Year-Old Man Comes to the Physician Complaining of 4-6