What are the possible causes of hematuria, especially in older adults with a history of diabetes, hypertension, or kidney disease?

Causes of Hematuria in Older Adults with Comorbidities

Hematuria in older adults with diabetes, hypertension, or kidney disease requires urgent evaluation for malignancy, which accounts for 30-40% of gross hematuria cases, while simultaneously assessing for glomerular disease, urinary tract infection, urolithiasis, and benign prostatic conditions. 1

Urologic/Malignant Causes (Most Critical in This Population)

Malignancy is the most important consideration in older adults and must be excluded first:

• Bladder cancer (transitional cell carcinoma) is the most frequently diagnosed malignancy in hematuria cases, presenting as painless gross hematuria in 70-80% of patients 1, 2
• Renal cell carcinoma increases in incidence with age and is detected through upper tract imaging 1
• Prostate cancer should be considered in older males with hematuria 1
• Risk factors amplifying malignancy risk include age >60 years, smoking history (especially >30 pack-years), occupational exposure to benzenes or aromatic amines, and history of gross hematuria 1, 3

Benign prostatic hyperplasia (BPH) is extremely common in older males and can cause hematuria, but does not exclude concurrent malignancy and requires full evaluation 1, 4

Renal/Glomerular Causes (Critical in Diabetic/Hypertensive Patients)

Diabetic nephropathy and hypertensive nephrosclerosis are leading causes of chronic kidney disease in this population, manifesting with hematuria when combined with glomerular injury 1

Glomerulonephritis presents with specific urinary findings:

• Tea-colored or cola-colored urine suggests glomerular bleeding 1, 3
• Dysmorphic red blood cells (>80%) indicate glomerular origin 1, 3
• Red blood cell casts are pathognomonic for glomerular disease 1, 3
• Significant proteinuria (>500 mg/24 hours) accompanies glomerular hematuria 1, 3

IgA nephropathy and post-infectious glomerulonephritis are common glomerular causes in adults 1

Infectious and Inflammatory Causes

Urinary tract infection is a common cause of both microscopic and macroscopic hematuria, particularly in diabetic patients who have increased susceptibility 1, 5

Interstitial nephritis can be drug-induced or related to analgesic abuse, relevant in older adults with multiple medications 1

Urolithiasis

Kidney and ureteric stones cause painful hematuria and are more common in patients with metabolic abnormalities 1, 5

Hypercalciuria and hyperuricosuria are metabolic causes that can lead to both hematuria and stone formation 1

Vascular and Systemic Causes

Renal papillary necrosis can occur in diabetic patients and those with sickle cell trait, causing hematuria 1

Nutcracker syndrome (left renal vein compression) causes hematuria with variable proteinuria 1

Medication-Related Considerations

Anticoagulants and antiplatelet agents (commonly used in diabetic/hypertensive patients) do NOT cause hematuria but may unmask underlying pathology—evaluation must proceed regardless of anticoagulation status 1, 3, 4

Critical Clinical Pearls

Never attribute hematuria to the following without full evaluation:

• Anticoagulation therapy (warfarin, DOACs, aspirin) 1, 4
• BPH alone in older males 4
• Diabetes or hypertension medications 1

Gross hematuria carries 30-40% malignancy risk and requires urgent urologic referral even if self-limited 1, 3

In patients with diabetes, hypertension, or known kidney disease, both urologic AND nephrologic evaluation may be necessary, as these patients can have concurrent glomerular disease and urologic malignancy 1, 3

Age >60 years automatically places patients in high-risk category requiring cystoscopy and CT urography regardless of other factors 1, 3