Management of Chronic Kidney Disease

Diagnosis and Initial Evaluation

An eGFR of 73 mL/min/1.73 m² in a young adult represents Stage 2 CKD and warrants immediate investigation to identify the underlying cause, as this level of renal impairment is abnormal for this age and suggests pathology rather than normal aging 1, 2
The American Journal of Kidney Diseases recommends obtaining a urine albumin-to-creatinine ratio (UACR) on a morning spot urine sample to assess for albuminuria, with normal being <30 mg/g, microalbuminuria being 30-300 mg/g, and macroalbuminuria being >300 mg/g 3, 4
Urinalysis with microscopy should be performed to evaluate for hematuria, pyuria, casts, or other abnormalities suggesting glomerular disease, infection, or interstitial nephritis 5
Repeat serum creatinine and eGFR in 3 months to confirm chronicity, as CKD requires abnormalities present for >3 months 6, 4
Renal ultrasound should be performed to assess kidney size, echogenicity, and rule out structural abnormalities or obstruction 5

The American Journal of Kidney Diseases recommends that if UACR <30 mg/g (normal), the patient has isolated reduced eGFR without proteinuria, and should be investigated for secondary causes including medications, obstruction, or congenital abnormalities, with monitoring of eGFR every 6-12 months 4
If UACR 30-300 mg/g (microalbuminuria), this indicates Stage 2 CKD with moderate risk, and the patient should have blood pressure optimized to <130/80 mmHg, be screened for diabetes, and consider ACE inhibitor or ARB if hypertensive, with monitoring of eGFR and UACR every 3-6 months 3, 6
If UACR >300 mg/g (macroalbuminuria), this indicates high-risk CKD requiring nephrology referral for possible kidney biopsy to establish diagnosis and guide immunosuppressive therapy if indicated 7

The Annals of Internal Medicine recommends targeting blood pressure <130/80 mmHg using lifestyle modifications, and ACE inhibitors or ARBs are recommended only if the patient has hypertension AND albuminuria ≥30 mg/g, as these agents reduce proteinuria and slow CKD progression 6, 3
ACE inhibitors or ARBs are NOT recommended for patients without hypertension to prevent CKD development, as trials showed no benefit and potential harm 3
An initial decline in eGFR of 10-20% after starting ACE inhibitor/ARB is acceptable and does not require discontinuation unless accompanied by hyperkalemia or excessive decline 8
Never combine ACE inhibitors with ARBs, as this increases adverse events without additional benefit 3

Immediate nephrology referral is indicated if there is a rapid decline in eGFR >5 mL/min/1.73 m² per year or sustained decline >20% 7, 9
Proteinuria >1 g/day (UACR ≥60 mg/mmol or PCR ≥100 mg/mmol) also requires nephrology referral, as kidney biopsy may be indicated 7
Unexplained low eGFR in a young patient (age <40) without obvious cause requires nephrology referral 7
Suspected hereditary kidney disease based on family history also requires nephrology referral 7

For Stage 2 CKD with eGFR 60-89 mL/min/1.73 m², repeat eGFR and UACR every 3-6 months depending on stability and albuminuria level 4
Annual screening for CKD complications including anemia, metabolic acidosis, hyperparathyroidism, and vitamin D deficiency is recommended once eGFR approaches 60 mL/min/1.73 m² 6