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BACKGROUND: Elevated serum alkaline phosphatase (ALP) levels are a risk factor for all-cause mortality in hemodialysis patients. Traditionally in Japan, ALP measurements were conducted using the JSCC method, which yields higher ALP measurement values than the IFCC method, mainly due to its increased sensitivity to intestinal ALP. METHODS: Serum total ALP levels before and after switching the assay method from JSCC to IFCC were compared among different blood types in 521 hemodialysis patients (Study 1). The association between ALP levels measured by the JSCC method and 7-year mortality was analyzed, including blood types and liver function parameters as covariates, in 510 hemodialysis patients (Study 2). RESULTS: ALP levels measured by the JSCC method were approximately three times higher than those measured by the IFCC method, with significant elevation in patients with blood types B and O compared to those with blood types A and AB. Similarly, ALP levels measured by the IFCC method were significantly higher in patients with blood types B and O compared to those with blood types A and AB (Study 1). The highest tertile of ALP levels showed a significantly increased risk of all-cause mortality, even after adjusting for patient background. However, this significance disappeared when serum liver function-related or inflammatory markers were included as covariates (Study 2). CONCLUSION: ALP levels measured by the JSCC method are associated with life prognosis, but caution should be exercised due to their elevation in patients with blood types B and O and in those with hepatic dysfunction or inflammation.
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INTRODUCTION: The usefulness of the Oxford classification (MEST-C score) for deciding the management approach for IgA nephropathy (IgAN) remains unclear. METHODS: Effects of steroid therapy on the long-term prognosis for all 858 patients with IgAN and patients classified according to each MEST-C score were evaluated using Kaplan-Meier and Cox regression analyses. Steroid responder score (SRS) and steroid nonresponder score (SNRS) were determined using individual pathology scores when steroids were found to be independently associated, or not, with clinical benefits. In addition, the effects of steroid therapy according to the total SRS/SNRS were analyzed. RESULTS: Steroid therapy improved the 20-year renal survival rates of patients with IgAN after matching (steroids[+] vs. steroids[-]; estimated glomerular filtration rate [eGFR] [ml/min per 1.73 m2]: 79.4 vs. 77.0, not significant; proteinuria [g/d]: 0.80 vs. 0.62, not significant; renal survival rate: 75.5% vs. 61.7%; P = 0.025) and of patients with M1, E1, S1, C1+2, and T0 scores. Therefore, we considered the total of the M1, E1, S1, and C1+2 scores (point 0: low, 1-2: medium, and 3-4: high) as the SRS and the total of the T1+2 scores (0: low and 1: high) as the SNRS. Multivariate Cox regression analyses revealed that steroid therapy improved the renal prognosis of patients with IgAN with high SRS and any SNRS, unlike patients with IgAN with medium SRS and any SNRS. CONCLUSION: Patients with M1, E1, S1, and C1+2 scores responded to steroid therapy; however, those with T1+2 scores did not. Although a high SRS was a useful indicator for steroid therapy, SNRS indicated resistance to steroid therapy.