Differential Diagnosis for 68y Female with Blood in Urine
Single Most Likely Diagnosis
- Degenerative Fibroid: The CT scan mentions an incidental calcification outside of the urinary system, likely a degenerative fibroid. Fibroids, especially in postmenopausal women, can undergo degeneration and cause bleeding, which could lead to hematuria (blood in urine).
Other Likely Diagnoses
- Urinary Tract Infection (UTI) with Negative Culture: Although the culture is negative, it doesn't entirely rule out a UTI, especially if the sample was taken after antibiotic use or if the infection is caused by a fastidious organism.
- Kidney Stones: Despite the CT not showing abnormalities of the kidneys or upper tracts, small stones might not be visible, and the patient could still be experiencing bleeding due to a stone.
- Bladder or Urethral Trauma: Given the absence of findings on the CT, trauma to the bladder or urethra could be a cause, especially if the patient has recently experienced any form of injury or instrumentation.
Do Not Miss Diagnoses
- Urothelial Carcinoma (Bladder or Upper Tract Cancer): Although the CT does not show abnormalities, cancer can sometimes be missed on imaging. Hematuria is a key symptom of urothelial carcinomas, and missing this diagnosis could be fatal.
- Renal Cell Carcinoma: Similar to urothelial carcinoma, renal cell carcinoma can present with hematuria, and a negative CT does not entirely rule out this possibility, especially if the tumor is small.
- Vascular Causes (e.g., Arteriovenous Malformation): Rare vascular abnormalities could cause hematuria and might not be visible on a standard CT scan.
Rare Diagnoses
- Endometriosis Involving the Urinary Tract: Although rare, endometriosis can involve the urinary tract and cause cyclic hematuria, especially if the endometriotic implants are near or involve the bladder or ureters.
- Sickle Cell Disease or Trait: In patients with sickle cell disease or trait, sickling in the low oxygen environment of the kidney medulla can cause ischemia and lead to hematuria.
- Tuberculosis: Genitourinary tuberculosis is a rare cause of hematuria in developed countries but should be considered, especially in patients with risk factors for TB exposure.