Müjgan ERCAN, Esra FIRAT OĞUZ, Serpil ERDOĞAN, Fatma Meriç YİLMAZ, Cevdet TÜRKYÜREK

Comparison of estimated glomerular filtration rate values calculated using serum cystatin C and serum creatinine

Amaç: Bu çalışmada sistatin C ve/veya serum kreatinin kullanılarak hesaplanan tahmini glomerüler filtrasyon hızı (eGFR) formüllerini karşılaştırma ve bunların diyabetli hastalarda mikroalbuminürik düzeydeki hasarı tespit edip edemeyeceğinin araştırılması amaçlanmıştır.Yöntemler: Çalışmaya tip 2 DM tanısı olan toplam 99 hasta dahil edilmiştir. Hastalar 24 saatlik idrar albumin miktarına göre normoalbuminürik (grup 1), mikroalbuminürik (grup 2), makroalbuminürik (grup 3) olarak üç gruba ayrılmıştır. Kreatinin klirensi ile Cockcroft-Gault (C-G), MDRD (Modification of Diet in Renal Disease) ve CKD-EPI (The Chronic Kidney Disease Epidemiology), eGFR1, eGFR2, eGFR3 düzeyleri formüllerle hesaplanmıştır.Bulgular: GFR değerlerinde Grup 1-3 ve Grup 2-3 arasında anlamlı farklılık gözlenirken, Grup 1 ile Grup 2 arasında anlamlı fark gözlenmedi. Sistatin C içeren eGFR formüllerinin diğer formüllere göre kreatinin klirensi ile daha anlamlı bir korelasyon gösterdiği bulundu.Sonuç: Diabetik hastaların takibinde Sistatin C bazlı formüllerin kullanımının, hesaplamada sistatin C kullanmayan diğer formüllere göre kreatinin klirens tahmininde daha iyi olduğu bulunmuştur. Ancak hiçbir formül böbrekteki mikroalbuminürik düzeydeki hasarı tespit edememiştir.

Serum sistatin C ve serum kreatinin kullanılarak hesaplanan tahmini glomerüler filtrasyon hızı değerlerinin karşılaştırılması

Objective: In this study, we aimed to compare estimated glomerular filtration rate (eGFR) formulas based on cystatin C and serum creatinine and investigate whether the formulas can detect the renal damage at microalbuminuric level in diabetic patients.Methods: Totally, 99 type 2 diabetic patients were included and divided into 3 groups according to 24 hour urine albumin levels as normoalbuminuric group (group 1), microalbuminuric group (group 2) and macroalbuminuric group (group 3). Creatinine clearance, Cockcroft-Gault (C-G), Modification of Diet in Renal Disease (MDRD), The Chronic Kidney Disease Epidemiology (CKD-EPI), eGFR1, eGFR2 and eGFR3 levels were calculated using formulas.Results: There were significant differences between group 1-3 and group 2-3, but there was no significant difference between group 1 and 2 in calculated GFR levels. Cystatin C-based formulas were found to have a better correlation with creatinine clearance. Conclusion: As a result, cystatin C-based formulas were found to predict creatinine clearance better than the other calculated GFR formulas in diabetic patients. However none of the formulas can discriminate the renal damage at microalbuminuric level. J Clin Exp Invest 2015; 6 (2).

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