What is the appropriate treatment plan for a patient with an estimated glomerular filtration rate of about 30 mL/min/1.73 m² (chronic kidney disease stage 3b)?

Treatment Plan for GFR 30 mL/min/1.73 m² (CKD Stage 3B)

Immediate nephrology referral is mandatory, and you must initiate comprehensive management addressing diabetes (if present), blood pressure control, mineral-bone disease, anemia, and preparation for potential renal replacement therapy. 1

Immediate Nephrology Referral

• Refer to nephrology immediately when GFR falls below 30 mL/min/1.73 m², as this threshold marks advanced CKD requiring specialized management and RRT planning. 1, 2
• Referral must occur at least 1 year before anticipated dialysis to avoid late-referral complications including inadequate vascular access preparation and suboptimal patient education. 2

Blood Pressure Management

• Target blood pressure <130/80 mmHg using an ACE inhibitor or ARB as first-line therapy, regardless of the reduced GFR. 1, 3
• Check blood pressure at every clinic visit, which must occur at least every 3 months. 1
• After initiating or adjusting ACE inhibitor/ARB doses, recheck serum creatinine and potassium within 5-7 days. 4, 2
• Continue ACE inhibitor/ARB if creatinine rises <30% from baseline, as this represents expected hemodynamic changes and does not indicate renal injury. 4, 2
• Discontinue or reduce dose only if creatinine rises >30%, potassium exceeds 5.5 mEq/L, or symptomatic hypotension develops. 4, 2

Critical Pitfall to Avoid

• Never discontinue ACE inhibitors/ARBs solely because GFR is 30 mL/min/1.73 m²—this is a common error that eliminates nephroprotection without justification. 4, 3

Diabetes Management (If Applicable)

SGLT2 Inhibitor Therapy

• Initiate dapagliflozin, empagliflozin, or canagliflozin immediately if the patient has diabetes and GFR ≥20 mL/min/1.73 m², as SGLT2 inhibitors reduce CKD progression, cardiovascular events, and mortality. 4
• SGLT2 inhibitors should be started regardless of albuminuria status when GFR is 20-90 mL/min/1.73 m². 4
• Continue SGLT2 inhibitor even if GFR falls below 20 during therapy, unless dialysis is initiated or intolerable adverse effects occur. 5
• Expect a transient 2-3 mL/min/1.73 m² decline in GFR within the first 2 weeks—this is hemodynamic and does not warrant discontinuation. 4

Metformin Management

• Metformin is contraindicated at GFR 30 mL/min/1.73 m²—stop it immediately and do not reinitiate. 1, 2, 3
• The KDIGO 2022 guideline explicitly states: "eGFR <30: Stop metformin; do not initiate metformin." 1

GLP-1 Receptor Agonist

• Add a long-acting GLP-1 RA (liraglutide, semaglutide, or dulaglutide) if glycemic targets are not met despite SGLT2 inhibitor use, or if SGLT2 inhibitors cannot be used. 1
• GLP-1 RAs provide additional cardiovascular and renal protection at GFR ≥30 mL/min/1.73 m². 4
• Dulaglutide and liraglutide require no dose adjustment at GFR 30 mL/min/1.73 m². 1

Glycemic Target

• Target HbA1c <7.0% (53 mmol/mol) to reduce microvascular complications, but individualize between 6.5-8.0% considering hypoglycemia risk. 4

Mineral-Bone Disease Management

• Measure 25(OH) vitamin D, intact PTH, calcium, and phosphorus at baseline and every 3-6 months. 1, 2
• If iPTH >100 pg/mL (or >1.5× upper limit of normal) and 25(OH) vitamin D <30 ng/mL, give vitamin D2 50,000 units orally monthly for 6 months. 1
• If corrected serum calcium <8.5 mg/dL (after addressing phosphorus), give elemental calcium 1 g/day between meals or at bedtime. 1
• Limit dietary phosphorus to 800-1,000 mg/day to prevent renal osteodystrophy. 2

Anemia Management

• Check hemoglobin every 3 months. 2
• If hemoglobin is low despite adequate iron stores, initiate erythropoietin or analogue therapy. 1
• Monitor for vitamin B12 deficiency if the patient was previously on metformin for >4 years. 1

Nutritional Management

• Limit dietary protein to 0.8 g/kg/day (ideal body weight) for non-dialysis CKD stage 3B. 1, 2
• Restrict sodium to <2 g/day (equivalent to <5 g sodium chloride/day). 2
• Monitor body weight and serum albumin every 3 months. 1
• If unintentional weight loss >5% or albumin drops >0.3 g/dL or is <4.0 g/dL, evaluate for causes and provide dietary counseling. 1

Dyslipidemia Management

• Measure fasting lipid panel (total cholesterol, LDL, HDL, triglycerides) at baseline. 1
• Target LDL <100 mg/dL and non-HDL cholesterol <130 mg/dL; treat triglycerides ≥500 mg/dL. 1

Renal Replacement Therapy Planning

• Discuss all RRT modalities (hemodialysis, peritoneal dialysis, transplantation, conservative management) now, as early education improves outcomes. 1, 2
• If the patient is a transplant candidate, refer for transplant evaluation immediately, as living-donor preemptive transplantation should be considered when GFR <30 mL/min/1.73 m². 1, 2
• If hemodialysis is planned, preserve veins suitable for vascular access—no venipunctures or IV lines in non-dominant forearm. 1
• Do not initiate dialysis based solely on GFR 30—dialysis is indicated only when uremic symptoms, refractory fluid overload, uncontrolled hypertension, progressive malnutrition, severe electrolyte abnormalities, or uremic bleeding develop. 2

Monitoring Schedule

• Clinic visits at least every 3 months with blood pressure check at each visit. 1
• Every 3 months: serum creatinine, eGFR, potassium, hemoglobin, albumin, body weight. 1, 2
• Every 3-6 months: calcium, phosphorus, intact PTH. 1, 2
• Every 6 months: urinary albumin-to-creatinine ratio (UACR). 4

Medications to Avoid

• NSAIDs are absolutely contraindicated—they worsen renal function and increase hyperkalemia risk. 2
• Thiazide diuretics are ineffective at GFR <30—use loop diuretics instead if volume overload is present. 2
• Opioid analgesics require marked dose reduction to prevent accumulation and toxicity. 2

Conservative Management Discussion

• All patients must be offered a discussion of conservative (non-dialysis) management as a legitimate option, particularly if elderly, frail, or with multiple comorbidities. 2
• Conservative management includes structured symptom control, psychological support, and end-of-life planning. 2