Presentation Authors: Satoshi Washino*, Saitama, Japan, Keiko Hosohata, Osaka , Japan, Masashi Oshima, Tsuzumi Konishi, Kimitoshi Saito, Tomoaki Miyagawa, Saitama, Japan
Introduction: Upper urinary tract obstruction (UUTO) and the subsequent development of hydronephrosis (HN) can cause kidney injuries, which results in acute or chronic kidney disease. Though a biomarker to assess the disease severity before intervention and monitor the disease after intervention is necessary there has been no good biomarker for UUTO-induced kidney injury. In this study we investigated the diagnostic values of vanin-1, a novel acute kidney injury marker, as a biomarker for adult UUTO.
Methods: Adult patients with HN and those without HN as a control group were enrolled while patients with urinary calculi were excluded. In the HN group, cases were divided into extrinsic UUTO such as malignant ureteral obstruction and intrinsic UUTO such as ureteral stricture, and further categorized into 5 patterns (0 normal, 1 partial obstruction, 2 obstruction, 3 reduced uptake, and 4 severe reduced uptake) based on the MAG3 renal scan results. Urine vanin-1 values in the bladder (BL) and renal pelvic (RP) in the HN group were compared with those in BL in the control group. In cases with the HN group having interventions, urine vanin-1 values were assessed at 1 and 4 weeks after intervention.
Results: A total of 49 cases, 21 in the control and 28 in the HN group, were assessed. In extrinsic UUTO the values of BL and RP vanin-1 were significantly higher than those in the control (6.73 Â± 9.86 and 20.5 Â± 25.9 vs 0.646 Â± 1.12 ng/mgCre, p < 0.05 and p < 0.05). Though the vanin-1 values in intrinsic UUTO (BL: 2.90 Â± 4.55 and RP and 5.36 Â± 1.94 ng/mgCre) were lower than those in extrinsic UUTO RP vanin-1 values were significantly higher than the values in the control. RP vanin-1 values increased according to the UUTO pattern while BL vanin-1 values increased up to pattern 3 but those in pattern 4 turned to be undetectable (Fig 1), which seems to be the cases with complete obstruction. When cutoff line was set at 3.4 ng/mgCre the sensitivity and specificity of the RP vanin-1 was 0.81 and 0.95. At 4 weeks after the intervention, 85% of patients experienced decreases of vanin-1 values compared to RP vanin-1 values at baseline.
Conclusions: Urinary vanin-1 is a sensitive and specific biomarker to detect the UUTO and monitor the clinical course of UUTO. The differential patterns between BL and RP vanin-1 values are useful to assess the severity of UUTO.
Source of Funding: Science Research Promotion Fund