Which statement best describes CKD stage 1?

• A. eGFR 60-89 with albuminuria
• B. eGFR ≥90 with evidence of kidney damage
• C. eGFR ≥90 with no signs of damage
• D. Evidence of kidney damage with eGFR ≥90 mL/min/1.73 m2

Answer: (D)

Stage 1 CKD is defined by normal or high filtration rate (eGFR at least 90 mL/min/1.73 m2) together with evidence of kidney damage. The description that best matches this is kidney damage present with an eGFR of 90 or higher. This means your kidneys are structurally or functionally damaged even though their filtration capacity is still in the normal range. Evidence of damage can be things like elevated urine albumin excretion (albuminuria), abnormal imaging, or biopsy findings.

Understanding this helps distinguish stage 1 from scenarios where the eGFR is normal but there’s no evidence of damage (which wouldn’t be CKD), or from stages where the eGFR is reduced (which correspond to CKD stages 2–5, depending on how low the eGFR is). In practice, stage 1 CKD often has few or no symptoms, so identifying damage markers and assessing risk factors (like diabetes or hypertension) guides management to slow progression, including blood pressure control (often with ACE inhibitors or ARBs if albuminuria is present), lifestyle measures, and avoiding nephrotoxins.