Differential Diagnosis for Urinary Incontinence

The patient presents with intermittent urinary incontinence, loss of small amounts of urine when coughing or sneezing, and a history of type 2 diabetes mellitus with complications. The key findings include a postvoid residual volume of 500 mL, decreased sensation in a stocking-glove distribution, absent Achilles tendon reflexes, and 2+ protein on urinalysis without leukocytes or erythrocytes.

• Single Most Likely Diagnosis

  • D) Overflow incontinence from acontractile bladder: This is the most likely mechanism given the patient's significant postvoid residual volume (500 mL), indicating incomplete bladder emptying, and the presence of peripheral neuropathy which can affect the autonomic nerves controlling bladder function.

• Other Likely Diagnoses

  • C) Intrinsic sphincter deficiency: Although less likely than acontractile bladder given the patient's presentation, intrinsic sphincter deficiency could contribute to incontinence, especially with the history of diabetes which can cause neuropathy affecting the sphincter.
  • B) Functional incontinence: Given the patient's gastroparesis and peripheral neuropathy, there might be a component of functional incontinence due to impaired mobility or sensation, but this seems less direct than the impact of acontractile bladder.

• Do Not Miss Diagnoses

  • A) Central nervous system disorder: Although the patient has peripheral neuropathy, a central nervous system disorder (like a spinal cord injury or multiple sclerosis) could also lead to neurogenic bladder and should not be missed due to its significant implications.
  • E) Overflow incontinence from bladder outlet obstruction: While the rectal examination shows a normal-sized prostate, bladder outlet obstruction (from any cause, including prostate issues, strictures, or stones) needs to be considered and ruled out due to its potential for serious complications.

• Rare Diagnoses

  • F) Pelvic floor muscle weakness: This could be a contributing factor but seems less likely given the patient's primary symptoms and the significant postvoid residual volume pointing more towards a neurogenic or obstructive cause.
  • G) Retroperitoneal fibrosis: A rare condition that could potentially cause urinary obstruction, but it would be unusual without other symptoms such as abdominal pain or mass.
  • H) Retroperitoneal lymphadenopathy: Similar to retroperitoneal fibrosis, this would be an uncommon cause of urinary incontinence and would likely present with additional symptoms.
  • I) Urinary tract infection: The absence of leukocytes or erythrocytes in the urinalysis makes this less likely, but it should always be considered in the differential diagnosis for urinary symptoms.