Evaluation and Management of Decreased eGFR with Hematuria and Dysuria

Immediate Diagnostic Steps

• The American College of Cardiology and Kidney Disease: Improving Global Outcomes (KDIGO) recommend repeat eGFR and urinalysis within days to weeks to distinguish acute kidney injury (AKI) from chronic kidney disease (CKD) 1, 2
• Obtain urinary albumin-to-creatinine ratio (UACR) on a spot urine sample to quantify proteinuria, as recommended by the American Diabetes Association 1, 3
• Perform urine microscopy to characterize the hematuria, looking specifically for red blood cell casts, dysmorphic RBCs, or white blood cells which indicate different pathologies, as suggested by the National Institute of Diabetes and Digestive and Kidney Diseases 2, 3

Establishing Chronicity and Cause

• Proof of chronicity requires evidence of kidney abnormalities present for ≥3 months, established through review of past eGFR measurements, past urinalysis results, imaging showing reduced kidney size or cortical thinning, medical history of conditions causing CKD, and repeat measurements at and beyond 3 months, as recommended by the Kidney Disease: Improving Global Outcomes (KDIGO) 1, 2
• Establish etiology using clinical context, medication review, and laboratory tests, including complete blood count, serum creatinine and cystatin C, blood glucose and HbA1c, lipid panel, and serum potassium, as suggested by the American Journal of Kidney Diseases 1, 2, 3, 4, 5, 6, 7, 8, 9

Red Flags Requiring Urgent Nephrology Referral

• Refer immediately to nephrology if any of the following are present: rapidly increasing albuminuria or development of nephrotic-range proteinuria, rapidly decreasing eGFR (>5 mL/min/1.73 m²/year), eGFR <30 mL/min/1.73 m², or uncertainty about etiology of kidney disease, as recommended by the American Journal of Kidney Diseases and Diabetes Care 3, 4, 9, 10

Initial Management While Awaiting Workup

• Target blood pressure <130/80 mmHg if CKD is confirmed, and use ACE inhibitor or ARB if hypertension is present with UACR ≥30 mg/g, but monitor creatinine and potassium closely, as recommended by the American Heart Association and American Diabetes Association 3, 4, 8, 9
• Check serum potassium within 1-2 weeks if starting or continuing ACE inhibitor/ARB, and assess for volume depletion which can worsen kidney function, as suggested by the American Journal of Kidney Diseases and Diabetes Care 6, 7, 9