Kidney Week

Abstract: TH-PO1081

Performance of Blood and Urine KIM-1 as Noninvasive Kidney Injury Biomarkers for Diagnosing Acute Tubular Injury (ATI) and Interstitial Fibrosis and Tubular Atrophy (IF/TA)

Session Information

• Pathology and Lab Medicine
  October 22, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Pathology and Lab Medicine

• 1700 Pathology and Lab Medicine

Authors

• Qin, Zhiqiang, Southern Medical University Nanfang Hospital State Key Laboratory of Organ Failure Research, Guangzhou, Guangdong, China

Zhiqiang Qin, MBBS

• Hou, Fan Fan, Southern Medical University Nanfang Hospital State Key Laboratory of Organ Failure Research, Guangzhou, Guangdong, China

Fan Fan Hou, MD, PhD

• Yang, Xiaobing, Southern Medical University Nanfang Hospital State Key Laboratory of Organ Failure Research, Guangzhou, Guangdong, China

Xiaobing Yang, MD, DrMed

Background

This is an observational cohort study. Serum and urinary KIM-1 were measured at renal biopsy in Testing and Validation cohorts. ATI and IF/TA were graded histologically. Multivariable restricted cubic spline, logistic regression, and ROC analyses were performed.

Methods

This is an observational cohort study. Serum and urinary KIM-1 were measured at renal biopsy in Testing and Validation cohorts. ATI and IF/TA were graded histologically. Multivariable restricted cubic spline, logistic regression, and ROC analyses were performed.

Results

There were 342 and 289 patients in the Testing and Validation cohorts, separately. Mean age was 37.0 vs 46.0 yrs, mean eGFR was 87.3 vs 81.1 mL/min/1.73m², median daily proteinuria was 1.7 vs 1.3 g/day, while serum/urinary KIM-1 levels did not significantly differ between the Testing and Validation cohorts. Compared to the lowest tertile, the highest tertile of serum KIM-1 was associated with 9.1-fold higher odds of ATI while 28.4-fold higher odds of IF/TA after multi-variable adjustment in the Testing cohort. As for urinary KIM-1, the highest tertile was associated with 25.0-fold higher odds of ATI while 10.5-fold higher odds of IF/TA compared with the lowest tertile after multi-variable adjustment in the Testing cohort. For diagnosing renal ATI, the AUC of urine KIM-1 outperformed serum KIM-1 (0.89 versus 0.83); whereas for IF/TA, the AUC of serum KIM-1 was higher than urinary KIM-1 (0.86 vs 0.73) in the Testing cohort. The Validation cohort showed consistent results.

Conclusion

Serum and urinary KIM-1 performed distinctly in diagnosing histological acute and chronic renal tubular injury. Urinary KIM-1 was more suitable for diagnosing ATI, and serum KIM-1 performed better in diagnosing IF/TA.

A&B: Diagnosing IF/TA; C&D: Diagnosing ATI

Funding

• Government Support – Non-U.S.