What is the management plan for a patient with a Glomerular Filtration Rate (GFR) of 15, indicating Impaired Renal Function?

Management of GFR 15 mL/min/1.73 m²

A patient with GFR 15 mL/min/1.73 m² requires immediate nephrology referral and urgent preparation for renal replacement therapy, as this represents Stage 4 CKD approaching end-stage renal disease. 1

Immediate Nephrology Referral

• Refer immediately to nephrology for any patient with eGFR <30 mL/min/1.73 m², as consultation at this stage reduces costs, improves quality of care, and delays dialysis. 1
• At GFR 15, the patient is at the threshold of Stage 5 CKD (kidney failure), making preparation for renal replacement therapy urgent. 1
• Dialysis initiation should be considered when GFR falls below 15 mL/min/1.73 m², though certain complications of kidney failure may justify earlier initiation even before reaching this threshold. 2

Monitoring Frequency and Laboratory Assessment

• Monitor creatinine, eGFR, urinary albumin excretion, and potassium at least twice yearly, increasing to quarterly or more frequently if rapid progression occurs, new medications are initiated, or clinical status changes. 1
• Measure serum calcium, phosphorus, and intact parathyroid hormone (iPTH) every 3 months to screen for secondary hyperparathyroidism and CKD-mineral bone disease. 3
• Check hemoglobin and complete anemia workup including iron studies, as erythropoietin deficiency becomes prevalent at this GFR threshold. 3
• Evaluate and correct metabolic acidosis by checking serum electrolytes, as this commonly develops at this level of kidney function. 1, 4
• Obtain complete lipid panel including triglycerides, LDL, HDL, and total cholesterol for cardiovascular risk evaluation. 3

Blood Pressure Management

• Target systolic BP <130 mmHg and diastolic BP <80 mmHg. 1, 4
• Use ACE inhibitors or ARBs as first-line agents for blood pressure control and kidney protection. 1, 4
• Check blood pressure at every clinic visit, minimum every 3 months. 3
• Small elevations in serum creatinine (up to 30% from baseline) with ACE inhibitors or ARBs should not be confused with acute kidney injury and do not require discontinuation. 4

Critical Medication Adjustments

Antidiabetic Medications (if applicable)

• Metformin: Contraindicated at eGFR <30 mL/min/1.73 m² and must be discontinued immediately. 1, 4
• Insulin: Reduce total daily dose by 35-50% due to decreased renal clearance and reduced gluconeogenesis. 1
• Canagliflozin: Maximum 100 mg daily; may continue for kidney and cardiovascular benefit until dialysis, though not expected to be effective for glycemic control in advanced CKD. 2, 1
• Sitagliptin: 25 mg daily if eGFR <30 mL/min/1.73 m². 2
• Alogliptin: 6.25 mg daily if eGFR <30 mL/min/1.73 m². 2
• Saxagliptin: Maximum dose of 2.5 mg daily if eGFR ≤45 mL/min/1.73 m². 2
• Glimepiride: Consider alternative if eGFR <15 mL/min/1.73 m²; if used, start lower dose (1 mg daily) with caution due to hypoglycemia risk. 2
• Glyburide: Avoid use - contraindicated. 2
• Exenatide: Contraindicated - not recommended with eGFR <30 mL/min/1.73 m². 2
• Lixisenatide: Avoid if eGFR <15 mL/min/1.73 m². 2
• Liraglutide, dulaglutide, and semaglutide require no dose adjustment but monitor eGFR when initiating or escalating doses. 2

Fluid Management Precautions

• Consult nephrology before administering IV fluids, as patients with eGFR 15 are at significantly increased risk of fluid overload. 1
• Monitor daily for signs of fluid overload when IV fluids are necessary. 1
• Assess for volume overload through history, physical examination, and weight at every clinical contact. 4

Preparation for Renal Replacement Therapy

• Begin patient education about the progressive nature of kidney disease and potential need for dialysis or transplantation. 1, 4
• Discuss options for renal replacement therapy including hemodialysis, peritoneal dialysis, and kidney transplantation. 3, 1
• Consider vascular access planning for hemodialysis or peritoneal dialysis catheter placement. 1, 4
• It may be optimal to perform kidney transplantation or begin home dialysis before patients reach CKD stage 5 (GFR <15). 2

Glycemic Management (if diabetic)

• Target HbA1c <7.0% for most patients, though higher targets may be appropriate for those with severe comorbidities, limited life expectancy, or high hypoglycemia risk. 1
• Monitor HbA1c twice yearly, increasing to quarterly if not at target or therapy changes. 1

Common Pitfalls to Avoid

• Do not delay nephrology referral - at GFR 15, the patient is at the threshold of end-stage renal disease and requires urgent specialist input. 1
• Do not continue metformin - it is absolutely contraindicated at this eGFR level. 1, 4
• Do not assume small creatinine increases with ACE inhibitors/ARBs represent acute kidney injury - up to 30% increase is acceptable and does not predict worse outcomes. 4
• Do not administer IV fluids liberally without nephrology input - these patients have severely impaired ability to handle volume loads. 1, 4
• Do not wait for symptoms to appear - clinical symptoms and signs are poorly predictive of reduced renal function until GFR is extremely low (<15 mL/min/1.73 m²). 5

Indications for Earlier Dialysis Initiation

Even when GFR is >15 mL/min/1.73 m², certain complications justify earlier initiation of dialysis therapy: 2

• Uremic pericarditis
• Severe fluid overload refractory to medical management
• Severe metabolic acidosis refractory to medical management
• Severe hyperkalemia refractory to medical management
• Uremic symptoms affecting nutrition or quality of life