Introduction: Autosomal dominant polycystic kidney disease (ADPKD) is characterized by progressive cystformation and variable renal function decline that frequently leads to end-stage renal failure... Show moreIntroduction: Autosomal dominant polycystic kidney disease (ADPKD) is characterized by progressive cystformation and variable renal function decline that frequently leads to end-stage renal failure. With theadvent of renoprotective treatment, there is renewed interest in noninvasive biomarkers to help identifypatients at risk of rapid disease progression at early stages. Urinary tissue inhibitor of metalloproteinases-2 (TIMP-2) and insulin-like growth factor–binding protein 7 (IGFBP7) have been validated as early markersof acute kidney injury. Because these markers are associated with tubular damage, we studied the per-formance of both markers in a cohort with chronic tubular pathology. We investigated whether thesebiomarkers may be useful to evaluate disease severity in ADPKD.Methods: In a cross-sectional analysis, we measured TIMP-2 and IGFBP7 in stored spot urine samples of pa-tients with ADPKD with various stages of chronic kidney disease (CKD) and healthy controls by enzyme-linkedimmunosorbent assay. Renal function was estimated using the CKD–Epidemiology Collaboration equation.Patients were stratified according to the Kidney Disease Outcomes Quality Initiative classification for CKD. In asubset of patients, total kidney volume (TKV; using magnetic resonance imaging [MRI]) was measured.Results: In 296 patients with ADPKD (45.5 11.5 years, 51.0% female, serum creatinine 106 [85–147] mmol/l),urine levels of TIMP-2 and IGFBP7 were not increased or tended to be lower as compared with 71 healthycontrols (46.5 18.5 years, 72.6% female). The levels did not differ across CKD stages, which remained so aftercorrecting for urine creatinine or osmolality, and for age, sex, and urine protein in multivariable analyses.Conclusions: Urinary levels of TIMP-2 and IGFBP7 were not higher in patients with ADPKD, and did notcorrelate with disease severity. Show less
