Urinary angiotensinogen is elevated in patients with nephrolithiasis

Area of Science:

• Nephrology
• Biomarker Discovery
• Renal Pathophysiology

Background:

• Elevated urinary angiotensinogen (UA) is a known prognostic biomarker for chronic kidney disease.
• The diagnostic potential of UA in nephrolithiasis patients requires further investigation.

Purpose of the Study:

• To evaluate the diagnostic utility of urinary angiotensinogen (UA) as a biomarker in patients with nephrolithiasis.
• To explore the correlation between UA levels, renal function markers, and kidney stone presence.

Main Methods:

• Urine samples from 60 nephrolithiasis patients and 50 healthy controls were analyzed for UA and α1-microglobulin using ELISA.
• Estimated glomerular filtration rate (eGFR) was calculated for all participants.
• Simple regression analysis was employed to assess correlations between UA, α1-microglobulin, and eGFR.

Main Results:

• Nephrolithiasis patients exhibited significantly higher median UA levels compared to controls (1250.78 ± 439.27 vs. 219.34 ± 45.27 pg/mL; P < 0.01).
• Patients with higher UA levels (>1250 pg/mL) had significantly higher serum creatinine (92.23 ± 18.13 μmol/L vs. 70.07 ± 11.17 μmol/L; P < 0.05).
• UA levels positively correlated with urinary α1-microglobulin (r = 0.733; P = 1.33 × 10⁻¹⁵) and negatively correlated with eGFR (r = -0.343; P = 1.03 × 10⁻⁴).

Conclusions:

• Urinary angiotensinogen (UA) serves as a novel diagnostic biomarker for nephrolithiasis.
• Elevated UA levels suggest renal tubular injury in patients with kidney stones.
• Further research into UA's molecular mechanisms and larger clinical trials are warranted.