Differential Diagnosis for a 74-year-old Male with Urinary Retention and Back Pain

The patient's presentation of urinary retention, pain, and back pain without fever suggests a range of possible diagnoses. Here's a categorized differential diagnosis:

• Single Most Likely Diagnosis

  • Benign Prostatic Hyperplasia (BPH): This is a common condition in older males where the prostate gland enlarges, potentially causing urinary retention. The patient's age and symptoms align with BPH, making it the most likely diagnosis.

• Other Likely Diagnoses

  • Urinary Tract Infection (UTI): Although the patient denies fever, UTIs can cause urinary retention and pain, especially in older adults. The absence of fever does not rule out a UTI.
  • Kidney Stones: Back pain and urinary retention can be symptoms of kidney stones, especially if the stone is obstructing the ureter.
  • Prostate Cancer: Similar to BPH, prostate cancer can cause urinary retention due to prostate enlargement. Given the patient's age, this is a plausible diagnosis.

• Do Not Miss Diagnoses

  • Spinal Cord Compression: This is a medical emergency that can cause urinary retention along with back pain. It's crucial to consider this diagnosis to prevent permanent neurological damage.
  • Abdominal Aortic Aneurysm (AAA): Although less common, an AAA can cause back pain and, if ruptured, can lead to shock and death. The absence of fever and the presence of back pain make this a "do not miss" diagnosis.
  • Sepsis from a Urinary Source: While the patient denies fever, sepsis can present atypically in the elderly. Sepsis from a urinary source is a life-threatening condition that requires prompt recognition and treatment.

• Rare Diagnoses

  • Neurogenic Bladder: This condition, resulting from nerve damage, can cause urinary retention. It's less likely but should be considered if other diagnoses are ruled out.
  • Phimosis or Paraphimosis: These conditions, related to the foreskin, can cause urinary retention but are less common in this age group and would typically present with additional symptoms.

Workup in the Emergency Department

The workup should include:

• Urinalysis: To check for infection, blood, or other abnormalities.
• Complete Blood Count (CBC): To assess for signs of infection or inflammation.
• Blood Urea Nitrogen (BUN) and Creatinine: To evaluate renal function.
• Imaging: A renal ultrasound or non-contrast CT scan can help identify kidney stones, obstruction, or other abnormalities.
• Prostate-Specific Antigen (PSA) Test: Depending on the clinical context and after discussion with the patient about the pros and cons.
• Neurological Examination: To assess for signs of spinal cord compression or other neurological issues.
• Abdominal Examination: To evaluate for tenderness or masses that could suggest an AAA or other abdominal issues.

This approach will help narrow down the differential diagnosis and guide further management.