Cystatin C is a sensitive marker for detecting a reduced glomerular filtration rate when assessing chronic kidney disease in patients with rheumatoid arthritis and secondary amyloidosis

Abstract

Serum cysC can identify a reduced GFR more accurately than sCr-eGFRs. Serum cysC >1.09 mg/L (i.e. eGFR(Rule)<60 mL/min/1.73 m(2)) could be a marker of a reduced GFR, and serum cysC >1.365 mg/L would strongly suggest a reduced GFR in patients who have RA with secondary amyloidosis.

Serum cystatin C is not an appropriate marker for kidney involvement in patients with primary Sjögren's syndrome

“…In some auto‐immune and auto‐inflammatory diseases such as familial Mediterranean fever (FMF) and RA, routine urinalysis in search of albuminuria and proteinuria is essential in the follow‐up of affected patients, as it appears early in the course of renal damage . Recent studies suggest that cysC is an independent, accurate, effective and early marker for assessment of renal involvement in FMF and RA patients, especially complicated by secondary amyloidosis . However, findings in this study suggest no association between serum cysC levels and proteinuria in pSS patients.…”

“…Moreover, studies have suggested significant associations between the degree of inflammation and cysC levels in different inflammatory clinical conditions. Although cysC has been proposed as an alternative marker, both for renal assessment and the degree of inflammation in a variety of chronic diseases, to our knowledge there is no study evaluating cysC levels and and their relation with renal involvement and acute inflammatory response in patients with pSS. Therefore, we aimed to evaluate serum cysC levels and their association with renal involvement and acute‐phase response in patients with pSS.…”

Factors contributing to discrepant estimated glomerular filtration values measured by creatinine and cystatin C in patients with rheumatoid arthritis

“…Nozawa et al 19 compared Cin with eGFR using the serum creatinine (eGFRcreat), eGFR using the serum cystatin C concentration (eGFRcys), the mean of eGFRcreat, eGFRcys (eGFRavg) and endogenous 24-h creatinine clearance × 0.715 (Ccr × 0.715) in 30 RA patients with a daily prednisolone dose less than 10 mg and demonstrated that eGFRcys was correlated best with Cin, and that the relationship was close to y = x. It has been reported that serum cystatin C concentration is affected by factors such as steroid dose 19 , disease activity 20 , 21 , and thyroid function 22 . However, in this study, most of the patients were receiving less than prednisolone 10 mg daily, and patients with moderate to high disease activity according to DAS28CRP were 7 (15.5%) in group A and 20 (10.3%) in group B, representing relatively small numbers.…”

Glomerular Filtration Rate Estimation using Cystatin C Levels Identifies Subclinical Renal Dysfunction in Patients with Rheumatoid Arthritis

“…Kazama et al reported that age, gender, glucose tolerance, proteinuria, systemic in ammation, lupus, or systemic use of steroids did not interfere in the relationship between sodium thiosulfate clearance and 1/CysC, and that serum CysC measurement is an excellent diagnostic test for identifying patients with subclinical renal dysfunction (9) . Sato et al reported that serum CysC >1.09 mg/L can identify a lower GFR more accurately than serum creatinine, with serum CysC >1.365 mg/L strongly suggesting a low GFR in patients who have RA with secondary amyloidosis (10) . To date, little attention has been paid to RA patients with renal dysfunction because they have low serum creatinine levels so their eGFR(cre) appears normal, but according to Kimura et al, serum CysC, which is unaffected by muscle quantity, is a potentially superior marker to creatinine for estimating renal function (11) .…”