Differential Diagnosis for 68 y/o Male with Urinary Symptoms

Single Most Likely Diagnosis

• Urinary Tract Infection (UTI): The symptoms of frequent urination, dark yellow urine, and slight lower back discomfort are classic for a UTI, especially in an older adult. The presence of a slight fever further supports this diagnosis.

Other Likely Diagnoses

• Benign Prostatic Hyperplasia (BPH): Given the patient's age and symptoms of frequent urination, BPH should be considered. However, the presence of fever and dark urine might suggest an infectious component rather than just BPH.
• Prostatitis: This condition, an inflammation of the prostate, could explain the lower back discomfort, frequent urination, and fever. It's a plausible diagnosis given the symptom complex.
• Dehydration: Although less likely to cause all symptoms directly, dehydration can lead to dark urine and fatigue. However, it wouldn't typically cause a fever or lower back discomfort without another underlying condition.

Do Not Miss Diagnoses

• Pyelonephritis: An infection of the kidney, which could present with similar symptoms including fever, flank pain (which could be described as lower back discomfort), and changes in urination. Missing this diagnosis could lead to severe consequences, including sepsis.
• Severe Sepsis or Septic Shock: Although less common, if the patient's condition is due to an infection (like a UTI or pyelonephritis) that has progressed, it could lead to sepsis, a life-threatening condition.
• Kidney Stones: While they might not directly cause fever, the pain associated with kidney stones can be severe and is often described in the flank or lower back. If a stone is obstructing urine flow, it could lead to infection, explaining the fever.

Rare Diagnoses

• Interstial Cystitis: A condition causing bladder pressure, bladder pain, and sometimes pelvic pain. The symptoms can overlap with those of a UTI but typically don't include fever.
• Malignancy (e.g., Prostate or Bladder Cancer): Although less likely to present with acute symptoms like fever, cancers of the prostate or bladder can cause changes in urination and, in advanced stages, systemic symptoms like fatigue. However, these would be less common initial presentations.