당뇨병환자의 신기능 평가지표로서 혈청 Cystatin C 측정의 유용성 = Usefulness of Serum Cystatin C for the Evaluation of Renal Function in Diabetic Patient

다국어 초록 (Multilingual Abstract)

Background : Diabetic nephropathy is the most frequent complication in patients with diabetes mellitus (DM). In clinical practice, the glomerular filtration rate (GFR) is often estimated from serum creatinine. Recently, serum cystatin C has been suggested being a better parameter for diagnosis of impaired renal function. We evaluated serum cystatin C as a potential new marker of GFR in diabetes patients. Methods : Serum cystatin C and serum creatinine (sCr) were measured in 73 DM patients to evaluate their usefulness in diabetic patients. DM patients were divided into three groups (whole DM patients, albuminuric patients, and DM patients with sCr<1 mg/dL). Serum cystatin C and sCr were compared with creatinine clearance (CCr). Results : The overall correlation coefficient for the reciprocal of serum cystatin C was superior to that of the reciprocal of serum creatinine in all three patient groups. With CCr cut-off values of 60 mL/min and 80 mL/min, receiver operating characteristic (ROC) plotting demonstrated that serum cystatin C had a higher sensitivity and specificity for detecting decreased GFR than did serum creatinine in all three patient groups. Conclusions : These findings suggest that serum cystatin C is superior to serum creatinine as a marker of GFR measured by correction or mean ROC-plot AUC in diabetic patients; therefore, serum cystatin C could be used for the early detection of the impairment of renal function.

국문 초록 (Abstract)

배경 : 당뇨병성 신증은 당뇨병 환자의 가장 흔하게 발생하는합병증 중의 하나이다. 현재 임상에서 사구체 여과율을 평가하기위한 지표로서 혈청 크레아티닌을 사용하고 있지만, 최근에 사구체 여과율을 반영하는 새로운 지표인 cystatin C가 소개되었다. 이에 본 연구에서는 당뇨병 환자에서 혈청 cystaitn C의 유용성에 대해 평가해보고자 하였다.방법 : 73명의 당뇨병 환자에서 혈청 크레아티닌과 혈청 cystatinC를 측정하였으며, 실험 환자군은 전체 당뇨병 환자군, 알부민뇨증을 보이는 당뇨병 환자군, 혈청 크레아티닌이 정상인 당뇨병 환자군으로 나누었다. 세 가지 환자군에서 각각 혈청 cystatin C, 혈청 크레아티닌, 24시간 요를 이용하여 산정된 크레아티닌 청소율을 기 준 으 로 서 로 비 교 하 였 다 .결과 : 모든 세 환자군에서 혈청 cystatin C가 혈청 크레아티닌보다 높은 상관계수를 보였다. 사구체 여과율의 역치를 60 mL/min과 80 mL/min 2가지로 설정하여 ROC 곡선 분석을 하였을때 세 환자군에서 모두 혈청 cystatin C가 혈청 크레아티닌 보다,민감도와 특이도가 더 높은 값을 보였다.
결론 : 이러한 결과로 볼 때 당뇨병 환자군에서 사구체 여과율을 반영하는 지표로서 혈청 cystatin C가 혈청 크레아티닌보다 조기에 신기능 저하를 찾아내는데 유용하게 이용될 것이다.

참고문헌 (Reference)

1 "Serumcystatin C may predict the early prognostic stages of patients withtype 2 diabetic nephropathy" 17 : 164-7, 2003

2 "Serum cystatin C in patients withmyeloma" Clin Chim Acta 309 : 1-6, 2001

3 "Serum cystatin C as an endogenousmarker of the renal Function" 37 : 389-95, 1999

4 "Relationship between serum cystatinC and creatinine in kidney and liver transplant patients" Clinica ChimicaActa 316 : 165-70, 2002

5 "Relationship amongserum cystatin C,serum creatinine,lean tissue mass and glomerularfiltration rate in healthy adults" 59 : 587-92, 1999

6 "Prognosticsignificance of serum cystatin C concentration in renal transplantrecipients:5-years follow up" 34 : 1152-8, 2002

7 "New insights into the significanceof microalbuminuria" 13 : 83-91, 2004

8 "Interest of cystatin C in screening diabetic patients for earlyimpairment of renal function" 52 : 1258-64, 2003

9 "Initial eval-uation of cystatin C measurement by particle-enhanced immuno-nephelometry on the Behring nephelometer systems" 1016-22,

10 "Evaluation of plasma cystatin C as a markerfor glomerular filtration rate in patients with type 2 diabetes" 52 : 363-70, 1999

11 "Evaluation of cystatin C and -2microglobulin as markers of renal function in patients with type 2diabetes mellitus" 17 : 160-8, 2003

12 "Diabetic nephropathy -an acquired orinherited disease" 1253 : 149-61, 2003

13 "Cystatin Cis not more sensitive than creatinine for detecting early renal impair-mentin patients with Diabetes" 38 : 310-6, 2001

14 "Cystatin C:Efficacy as screening test for reduced glomeru-lar filtration rate" 20 : 97-102, 2000

15 "Cystatin C:An ImprovedEstimator of Glomerular Filtration Rate" 48 : 699-707, 2002

16 "Conforming the utility of four kidney biomarker tests in a longitudinalfollow up study" 25 : 797-817, 2003

17 "Comparison of cystatin C versus creatinine for detection of mildrenal failure" 54 : 374-81, 2000

18 "Biologic variation of cys-tatin C:implication for the assessment of glomerular filtration rate" 44 : 1535-9, 1998

19 "A comparison between cystatinC,plasm a creatinine and the Cockroft and Gault formular for theestimation of glomerular filtration rate" 18 : 2024-31, Transplant2003