CysC In Patients Research Articles

A biomarker for estimating no-reflow phenomenon in PCI-treated non-ST-segment elevation myocardial infarction patients: serum Cystatin C

Aims: Cystatin C (Cys-C) is a biochemical marker associated not only with renal function but also with inflammatory processes. We aimed to investigate the relationship between the post-percutaneous coronary intervention (PCI) no-reflow phenomenon (NRP) and Cys-C in patients with non-ST-segment elevation acute coronary syndrome (NST-ACS).
 Methods: This retrospective, single-center observational study consecutively enrolled patients who were hospitalized with a diagnosis of NST-ACS and underwent PCI between October 2021 and February 2022. Baseline characteristics, medications, admission laboratory parameters, and angiographic features were recorded. Logistic regression and sensitivity analyses were performed to identify parameters associated with NRP.
 Results: Out of 199 patients (mean age: 62.0±10.3, 59.8% male), 36 (18.1%) developed NRP. Patients who developed NRP had a lower ejection fraction (49.7±10.3% vs. 53.5±7.1%, p=0.046) and were less likely to be male (36.1% vs. 65.0%, p=0.001). Additionally, individuals with NRP exhibited higher blood urea and C-reactive protein levels than those without NRP (p1.1 mg/L for Cys-C determined NRP with 72.2% sensitivity and 66.9% specificity (area under the curve=0.711, p

Correlation between Serum Homocysteine Level and Cystatin C Elevation in Patients with H-type Hypertension

[Objective] To investigate the correlation between serum levels of homocysteine (Hcy) and cystatin C (CysC), a sensitive marker of renal function, in patients with H-type hypertension. [Methods] A total of 857 patients with essential hypertension without moderate to severe renal impairment (estimated glomerular filtration rate ≥ 60 ml/(min-1.73 m2) by Modification of Diet in Renal Disease equation) visited the Seventh Affiliated Hospital of Sun Yat-sen University from May 2018 to May 2020 were selected as the research subjects. The observation group (n = 635) consisted of patients with H-type hypertension (essential hypertension with Hcy ≥ 10 mmol/l) and the control group (n = 222) consisted of patients with non-H-type hypertension (essential hypertension with Hcy < 10 mmol/l). Multivariate logistic regression analysis, curve fitting, and threshold analysis were used to evaluate the correlation between elevated CysC and serum Hcy levels. [Results]CysC in observation group was significantly higher than that in control group (0.96 ± 0.160 vs 0.84 ± 0.13 mmol/l; p < 0.001). Multivariate logistic regression analysis, curve fitting, and threshold analysis showed that there was a significant difference in the risk of CysC elevation between Hcy levels at 10-25 mmol/L and Hcy levels below 10 mmol/L; there was no significant difference in the risk of CysC elevation between Hcy levels above 25 mmol/L and Hcy levels below 10 mmol/L. The inflection point of Hcy was 15.23 mmol/L, and when Hcy was < 15.23 mmol/L, the probability of CysC elevation increased by 27\% for each 1 mmol/L increase in Hcy (OR 1.27, 95\% Cl: 1.12, 1.44; P = 0.0002). When Hcy was > 15.23 mmol/l, the probability of CysC elevation was reduced by 4\% for each 1 mmol/l increase in Hcy (OR 0.96, 95\% Cl: 0.92, 1.01; P = 0.1085). [Conclusions] The risk of CysC in patients with H-type hypertension is higher than that in patients with non-H-type hypertension when Hcy is between 10-25 mmol/L; and the probability of cystatin C elevation is the highest when Hcy is at 15.23 mmol/L.

Cystatin C as a New Biomarker in Patients with Chronic Kidney Disease a Review and Meta-Analysis

The objective of this study was to evaluate the correlation between cystatin C (CysC) and patients with Chronic Kidney Disease (CKD). Prospective or retrospective cohort studies which compared the levels of CysC in patients with CKD and healthy controls were searched on PubMed, Contents, CINAHL and EMBASE from 2013 to December 31, 2020. R3.5.2 software was utilized to perform data analysis. Based on the meta-analysis criteria, 17 randomized controlled trials with 3592 cases of CKD afnd 5234 cases of healthy controls were included in this study. A random effect model suggested that the level of CysC in patients with CKD was higher than that in healthy controls with the Mean Difference (MD) at 0.46, 95%CI: [0.39; 0.54], Z = 12.30, P<0.0001. Moreover, there was significant heterogeneity (I2 = 98%; P<0.01). The sensitivity analysis showed that the random effect model was robust to the MD. The ROC curve result indicated the area under the AUC of CysC (0.805) was greater than that of creatinine (SCr) (0.683). This study found that CysC levels were more sensitive than SCr in CKD evaluation. Furthermore, CysC can be considered as a new biomarker in patients with CKD.

Cystatin C and arterial stiffness in patients without chronic kidney disease.

Cystatin C (cysC) is freely filtered in the glomeruli, and its serum concentration is independent of muscle mass, diet, gender, or age. In patients with chronic kidney disease (CKD), cysC is associated with advanced atherosclerosis and increased arterial stiffness. The purpose of this study was to define possible associations between arterial stiffness parameters and cysC in patients without CKD. The study included 111 non-CKD patients. Basic demographic and laboratory data were recorded. Arterial stiffness was measured by applanation tonometry (sphygmocor, Australia). Mean age of the patients was 64.3 ± 9.4 years, 65.8% were men. Most common co-morbidities were arterial hypertension (AH) (n = 86, 77.5%), hyperlipidemia (n = 64, 57.7%), and diabetes mellitus (DM) (n = 22; 19.8%). Mean creatinine was 77.7 ± 13.8 µmol/L (range 49 - 108), estimated GFR 81.3 ± 9.4 mL/min/1.73m2 (range 62 - 90), and cysC 0.94 ± 0.18 mg/L (range 0.67 - 1.63). Mean carotid-femoral pulse wave velocity (cfPWV) was 10.1 ± 2.4 m/s (range 6.2 - 16.8), subendocardial viability ratio (SEVR) 165.7 ± 36.1% (range 92 - 299), ejection duration (ED) 33.8 ± 4.4 ms (range 22 - 46), and pulse pressure (PP) 46.6 ± 14.8 mmHg (range 17 - 94). A statistically significant association was found between cysC and cfPWV (r = 0.472, p < 0.001), SEVR (r = -0.316, p < 0.001), ED (r = 0.217, p = 0.025), and pulse pressure (PP) (r = 0.241, p = 0.012). Multiple regression analysis between arterial stiffness parameters and cysC, age, male gender, AH, DM, hyperlipidemia, and eGFR confirmed a statistically significant and independent association between cysC and cfPWV (β = 0.220, p = 0.038), between cysC and SEVR (β = -0.278, p = 0.017), and between cysC and ED (β = 0.241, p = 0.045). Elevated cysC is associated with increased cfPWV, increased ED, and decreased SEVR.

Estimation of Glomerular Filtration Rate and Predicting Diagnostic Accuracy of Cystatin C and Creatinine in Detection of Renal Function among Longstanding Type-2 Diabetics

Introduction: Estimation of Glomerular Filtration Rate (GFR) is dependent on Serum Creatinine (SCr). Though, a sudden decrease in GFR would not result in rapid rise in concentrations of SCr, as they are imprecise but it leads to the over diagnosis of Chronic Kidney Disease (CKD). Aim: To calculate GFR using Cystatin-C (Cys-C) based formulas to contrast its accuracy with SCr based formulas and to predict the diagnostic accuracy of Cys-C in patients with diabetes. Materials and Methods: A total 48 type-2 diabetic patients were diagnosed with CKD and their GFR was assessed using the Cys-C and SCr. GFR was measured and estimated using three equations (Cockcroft-Gault (CG), Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CDK-EPI), that are based on SCr and three equations (LeBricon, Grubb and Hoek) based on Cys-C among the 48 CKD patients. The filtration rate was measured using labelled diethylenetriaminepentaacetic acid (99mTc-DTPA) renal scan method as the standard for comparison. The Receiver Operating Characteristics (ROC) analysis was used to evaluate the diagnostic accuracy of the filtration rate. Results: A significant association was observed (p=0.0001) among both the estimates which were equivocal when compared with measured iGFR, SCr and Cys-C based GFR estimate. A greater difference of Area Under the Curve (AUC) was observed between SCr (0.765±0.07) and Cys-C (0.569±0.09) (p=0.04) in the ROC analysis at a creatinine clearance &lt;60 mL/min/m2. conclusion: The SCr and Cys-C based formulae has equivocal performance in estimating GFR. SCr could be a better marker to estimate GFR among patients with Cr clearance &lt;60 mL/min/m2.

Comparative assessment of renal function by cystatin C level in patients with hypertension and extrasystole

Although the tight connection of the cardiovascular system and the kidneys is well known, using of cystatin C (Cys-C) opens new horizons in studying early renal failure stages. The study aimed to compare the functional status of the kidneys in patients with hypertension and extrasystole to the level of Cys-C. 156 patients with stage II hypertension (EH II) were examined. 124 of them had frequent symptomatic extrasystoles (74 – of supraventricular origin and 50 – ventricular), 32 patients had no arrhythmias, and were referred to the comparison group. The control group consisted of 30 healthy people with normal blood pressure (BP). All patients underwent a complete clinical examination, blood pressure measurement, daily blood pressure monitoring, daily electrocardiogram monitoring, echocardiography, and determination of renal function (creatinine, blood electrolytes, serum cystatin C) followed by calculation of glomerular filtration rate (GFR). The level of Cys-C in patients with hypertension was significantly higher (p&lt;0.001) compared with healthy individuals. Among patients with arrhythmias, the highest level of Cys-C was noted in patients with ventricular arrhythmias. The correlation analysis showed that the level of Cys-C was higher in the presence of frequent extrasystoles (namely of ventricular origin), smoking, high blood pressure, increased systolic and pulse blood pressure, the presence of concentric left ventricular hypertrophy, dyslipidemia, increased creatinine level and decreased GFR. All three EH II patient groups had significantly lower GFR (calculated by creatinine level) (p&lt;0.001). The lowest creatinine-based GFR was revealed in patients with ventricular extrasystole. All patients with EH II had significantly lower Cys-C based GFR than the control group (p&lt;0.001). Mean Cys-C-based GFR values in patients with extrasystole were significantly lower than in patients without extrasystole (p&lt;0.03). The analysis of GFR levels depending on the extrasystole origin was provided. The lowest level of GFR was recorded in patients with ventricular extrasystole. It was significantly different from the patients with supraventricular extrasystole (p=0.02). Our findings confirm the opinion of other researchers that Cys-C is an early marker of renal dysfunction in patients with hypertension, which is more sensitive than creatinine. Another finding is that ventricular extrasystole is more hemodynamically and metabolically unfavorable compared to supraventricular based on clinical and prognostic evaluation.

Cystatin C, a Controversial Biomarker in Hypothyroid Patients under Levothyroxine Therapy: THYRenal, a Pilot Cohort Observational Study.

Background: Cystatin C (Cys-C) is recognized as one of the most reliable renal function parameters in the general population, although it might be biased by thyroid status. Herein, we tested Cys-C and conventional renal parameters in a cohort of hypothyroid patients treated with Levothyroxine. Methods: Eighty-four hypothyroid patients were recruited and subgrouped according to their serum thyroid-stimulating hormone (TSH) values as a paradigm for therapeutic targeting (n = 54, optimal TSH range = 0.5–2 µIU/mL; n = 30, TSH > 2µIU/mL). Serum Cys-C, creatinine, measured and estimated glomerular filtration rates (mGFR and eGFR) were assessed. Results—mGFR and eGFR were comparable among the two subgroups, whereas Cys-C was significantly higher in patients with suboptimal TSH values (>2 µIU/mL) (p < 0.0001). TSH significantly correlated with Cys-C in the overall patient group, and in the subgroup with TSH above the target value (>2 µIU/mL). Out of 20 patients with abnormal Cys-C, 19 had suboptimal TSH levels. Receiver operating characteristic (ROC) analysis indicated Cys-C as a moderately accurate diagnostic tool (AUC = 0.871) to assess Levothyroxine replacement efficacy in hypothyroid patients (63% sensitivity, and 98% specificity). Conclusions: The observation of increased serum Cys-C in patients with suboptimal TSH would suggest the importance of a careful interpretation by clinicians of this biomarker in the case of hypothyroid patients.

Serum Ang and CysC Levels in Essential Hypertension Complicated by Hypertensive Emergencies.

To explore the value of serum angiotensin Ⅱ (Ang II) and cystatin C (CysC) levels in predicting hypertension emergency in patients with essential hypertension. Experimental study. Hangzhou Hospital of Zhejiang Medical and Health Group, from January 2018 to February 2020. One hundred and thirty seven patients with essential hypertension were divided into hypertension emergency group (Group A, 42 cases) and essential hypertension group without emergency (Group B, 95 cases). Ninety-five healthy subjects were selected as control group. Correlation between serum Ang and CysC and essential hypertension complicated with hypertension emergency was analysed. Diagnostic ability of Ang and CysC was analysed by ROC curve. Serum Ang and CysC levels in Group A and B were higher than those in control group (all p <0.001); serum Ang II and CysC levels in Group A were higher than those in Group B (both p <0.001). Serum Ang II and CysC levels were positively correlated with essential hypertension complicated with hypertension emergency (r=0.480, p <0.001; r=0.485,p <0.001, respectively). Area under ROC curve of serum Ang II combined with CysC for predicting hypertension emergency was 0.905 (95%CI: 0.854-0.955), which was larger than that of serum Ang II, CysC alone. Serum Ang II and CysC in patients with primary hyperemia complicated with hypertension emergency were higher. Combined detection of serum Ang II and CysC might be used as an effective reference index for predicting hypertension emergencies in patients with essential hypertension. Key Words: Serum, Angiotensin Ⅱ (Ang II), Cystatin C (CysC), Essential hypertension, Hypertension emergency.

Factors Resulting Correlation and Differences in Renal Function Evaluation Index Using the Serum Cystatin C and Creatinine as Measured by an Enzymatic Method

We previously reported the association of the estimated glomerular filtration rate (eGFRcreat) calculated from the serum creatinine level (S-Cr) measured using the Jaffe method with the GFR (eGFRcys) estimated from the serum cystatin C level (CysC). However, few studies have compared the eGFRcreat using the enzymatic method with the eGFRcys. It is unclear whether there are differences in the results of renal function assessment. The purpose of this study was to compare the eGFRcreat calculated from the S-Cr with the eGFRcys calculated from the CysC in patients in whom the S-Cr and CysC were simultaneously measured using the enzymatic method, examine the correlations of respective parameters, and clarify physiological factors involved in differences among the parameters. The subjects were 1334 patients treated in 5 institutions. The mean values and correlation coefficient were statistically analyzed using Student's t-test and Pearson's test, respectively. Influential factors between formulae were analyzed using multiple regression analysis. The mean eGFRcreat was 67.0 mL/min/1.73 m2, being significantly higher than the mean eGFRcys (63.2). Multiple regression analysis showed that factors influencing differences in the S-Cr and CysC included the sex, age, serum albumin, and blood urea nitrogen BUN/S-Cr. Furthermore, factors involved in the overestimation of the eGFRcreat in comparison with the eGFRcys included the serum albumin and BUN/S-Cr. The differences between the eGFRcreat calculated from the S-Cr and eGFRcys were less marked than when adopting the Jaffe method in our previous study. However, the eGFRcreat were higher than the eGFRcys in patients with malnutrition or dehydration.

Cystatin C promotes cognitive dysfunction in rats with cerebral microbleeds by inhibiting the ERK/synapsin Ia/Ib pathway.

Although higher serum level of cystatin C (CysC) was observed in patients with cerebral microbleeds, its associated role in the disease has not been elucidated. In this work, a rat model of cerebral microbleeds was created with the aim of investigating effects of CysC on cognitive function in rats with cerebral microbleeds and the underlying mechanism. Serum samples of patients with cerebral microbleeds and healthy people of the same age were collected. Levels of cystatin C expression in these samples were measured using CysC kits. Moreover, 48 spontaneously hypertensive rats (SHRs) bred under specific pathogen-free (SPF) conditions were randomly divided into 4 groups: sham surgery control group (sham), model group (CMB), model + empty vector control group (CMB + vehicle), and model + cystatin C overexpression group (CMB + CysC). Expression levels of CysC in hippocampus of rats in each group were measured by western blot analysis. The Y-maze was used to evaluate cognitive function of rats. Hippocampal long-term potentiation (LTP) in rats was assessed by the electrophysiological assay. Alterations in levels of p-ERK1/2 and p-synapsin Ia/b proteins associated with cognitive function were identified by western blot analysis. The serum levels of CysC in patients with cerebral microbleeds were significantly upregulated (P<0.001). After injection of CysC, its expression levels in rat hippocampus were significantly increased (P<0.001), which enhanced the decline in learning and memory function, as well as the decrease of LTP in the rat model of cerebral microbleeds (P<0.001). Western blot results showed that injection of CysC further reduced the levels of p-ERK1/2 and p-synapsin Ia/b in the rat model of microbleeds (P<0.001). CysC was up regulated in serum of patients with cerebral microbleeds. It promoted cognitive dysfunction in rats with microbleeds by inhibiting ERK/synapsin Ia/Ib pathway.

The Clinical Importance of Cystatin C and Hepatic Artery Resistive Index in Liver Cirrhosis.

Background: Data suggest cystatin C (CysC) levels and hepatic artery resistive index (HARI) correspond to the progression of chronic liver disease. We aimed to evaluate the clinical significance of these parameters in assessment of fibrosis in patients with liver cirrhosis. Methods: The cross-sectional study included 63 patients with liver cirrhosis. A control group consisted of 30 age- and gender-matched healthy persons. Results: We confirmed significantly higher values of CysC in patients with cirrhosis compared to control group (p = 0.036). Average value of HARI in the examined group was increased (0.72 ± 0.06) and there was the statistically significant difference compared to controls (0.66 ± 0.03) (p < 0.001). We found statistically significant correlation between HARI and CysC in the study group. Analyzing the possibility of distinguishing healthy subjects from patients with fibrosis, we have found that the area under the curve is far greater in the HARI index than CysC. Comparison of CysC among Child–Pugh stages and correlation with a model for end-stage liver disease (MELD) score showed statistically significant results. Conclusion: We confirmed HARI is a more accurate parameter than CysC in discriminating healthy subjects from patients with fibrosis, while CysC could be a better indicator of the stage of liver cirrhosis.

Association of serum Cystatin C with neuromyelitis optica spectrum disorders.

The relationship between Cystatin C (CysC) and neuromyelitis optica spectrum disorders (NMOSD) is unknown. Serum CysC levels were measured in 105 Chinese patients with NMOSD (53 in relapse, 52 in remission) and 109 healthy controls (HCs). The association of CysC with NMOSD and its clinical and magnetic resonance imaging parameters were evaluated. Cystatin C levels were significantly lower in patients with relapsing NMOSD than in those in remission (P < 0.001) or HCs (P < 0.05). CysC levels in NMOSD remission were higher than in HCs (P = 0.002). CysC levels were positively associated with age and negatively associated with brain lesion numbers in relapsing NMOSD (r = -0.252, P = 0.069). Our results indicate a reduced serum level of CysC in patients with relapsing NMOSD and an increased level in remission. Further studies on the role of CysC in NMOSD are warranted.

Expression and application of serum NGAL, KIM-1 and CysC in patients with renal tumor

Objective To investigate the expression and clinical significance of serum neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1) and serum cystain C (CysC) in patients with renal tumor. Methods A total of 120 patients with renal tumor diagnosed in International Hospital of Zhejiang University from January 2016 and March 2016 was selected as the research object, and 60 patient medical volunteers were selected as control. The levels of NGAL and KIM-1 were determined by enzyme-linked immunosorbent assay (ELISA) method, and the levels of serum CysC were determined by electrochemical luminescence method. The levels of NGAL, KIM-1, and CysC were compared, and their relevance was analyzed. Results The levels of NGAL, KIM-1, and CysC in research object were significantly higher than the control group; the levels of NGAL, KIM-1, and CysC in malignant tumor patients were significantly higher than the benign tumor; the levels of NGAL, KIM-1, and CysC in one level of serum tumor were lower than the two levels, three levels, and four levels of tumor patients. With the more Furhman grading, the levels of NGAL, KIM-1, and CysC were higher, the differences were statistically significant (P<0.05). The levels of serum NGAL, KIM-1, and CysC were significantly related to renal damage degree. The levels of serum NGAL were significantly positively related to KIM-1 and CysC (r= 0.812 and 0.765). The levels of serum KIM-1 expression were significantly positively related to CysC (r=0.832) (P<0.05). Multiple regression analysis showed that the levels of serum NGAL, KIM-1, and CysC were significantly related to patients with renal tumor Furhman classification (P<0.05). Conclusions The levels of NGAL, KIM-1 and CysC were significantly increased in patients with renal tumor renal tumor, the higher the clinical stage, the higher expressive level, and were significantly related to renal damage degree. NGAL, KIM-1, and CysC can be used as the diagnostic markers of renal tumor. Key words: Gelatinases/ME; Membrane glycoproteins/ME; Cystatins/ME; Kidney neoplasms/ME

Monitoring the estimated glomerular filtration rate (eGFR) in patients with small-cell lung cancer during chemotherapy: equations based on serum creatinine or cystatin C?

This study compared the differences between the estimated glomerular filtration rate (eGFR) calculated by several equations based on serum creatinine (Scr) and cystatin C (CysC) concentrations for monitoring renal function in patients with small-cell lung cancer (SCLC) during chemotherapy. Seventy-one patients with SCLC were retrospectively analyzed. The eGFR before and after each chemotherapy cycle was calculated by the following equations: the chronic kidney disease epidemiology collaboration (CKD-EPI) equation, the modification of diet in renal disease (MDRD) equation, the Cockcroft-Gault (CG) equation, and five CysC-based equations. The patients were compared among the different eGFR groups. The mean decreases in eGFRCKD-EPI (-2.25±9.89ml/min/1.73m2) between each treatment cycle were more significant than the decreases in eGFRCG (-0.46±10.17ml/min/1.73m2), eGFRMDRD (-0.48±9.79ml/min/1.73m2), and five calculated eGFRCysC (p<0.05). Single-/multiparameter analyses showed that patients with a higher body mass index (BMI>23) and receiving more treatment cycles (>3) were at increased risk for developing renal impairment with an eGFR less than 60ml/min/1.73m2 during chemotherapy. The eGFR calculated by the CKD-EPI equation changed more significantly between each chemotherapy cycle than did the eGFR from the other equations based on Scr or CysC in patients with SCLC. Oncologists should pay more attention to the renal function of specific patient groups during treatment.

Cystatin C is an Independent Risk Factor and Therapeutic Target for Acute Ischemic Stroke.

Cystatin C (CysC) has been used as a renal function indicator and a strong predictor of cardiovascular events. In this study, we determined the prognostic value of serum CysC in patients with acute ischemic stroke (AIS) and examined its protective role on ischemic brain injury. First-ever stroke patients (601 cases) and control subjects (325 cases) were recruited. Serum CysC level in patients with AIS were significantly higher than that in controls. Multivariate logistic regression analyses showed that elevated CysC is an independent risk factor of AIS; the odds ratio (95% confidence interval) was 9.80 (3.12-30.83). The integrated population was divided into quintiles according to serum CysC. Compared with the first quintile, the odds ratios of risk for AIS in fourth quintile and fifth quintile were 1.92 (1.08-3.40) and 2.88 (1.49-5.54), respectively. Serum CysC was not associated with neurological deficits and the location of ischemic area; however, serum CysC in patients decreased after one-week therapy. This was consistent with CysC expression after ischemia/reperfusion injury in a mouse focal ischemia/reperfusion injury model. Exogenous CysC exerted neuroprotective effects by reducing infarct volume in this animal stroke model. Therefore, serum CysC is highly associated with AIS and is an independent prediction marker for AIS. Since our findings demonstrated the protection of exogenous CysC on ischemic brain injury, CysC is a novel and promising therapeutic target for AIS.

Cystatin C as a Predictor for Outcomes in Patients with Negligible Renal Function

Background: High serum cystatin C (CysC) has been associated with clinical risks independently of the glomerular filtration rate (GFR). This study aims to investigate the predictive power of CysC in patients with a negligible GFR. Methods: Patients on chronic hemodialysis or peritoneal dialysis were enrolled for measurement of CysC levels and were followed up for one year. A daily urine amount <100 ml was considered negligible residual renal function (RRF). Results: CysC results were available in 183 dialysis patients. Of these, 131 patients had a negligible RRF. The multivariate Cox proportional hazards model showed that CysC was an independent predictor of fatal and nonfatal cardiovascular and infection events in all dialysis patients and in dialysis patients with a negligible RRF. Conclusion: CysC maintained its predictive power for adverse outcomes in patients with no meaningful GFR, indicating that the prognostic value of CysC is independent of the GFR. i 2014 S. Karger AG, Basel

Impact of Growth Hormone on Cystatin C

Background: Cystatin C (CysC) is an alternative marker to creatinine for estimation of the glomerular filtration rate (GFR). Hormones such as thyroid hormones and glucocorticoids are known to have an impact on CysC. In this study, we examined the effect of growth hormone (GH) on CysC in patients with acromegaly undergoing transsphenoidal surgery. Methods: Creatinine, CysC, GH and insulin-like growth factor-1 (IGF-1) were determined in 24 patients with acromegaly before and following transsphenoidal surgery. Estimated GFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration formula. Results: In all patients, surgical debulking resulted in decreased clinical disease activity and declining GH/IGF-1 levels. Postoperatively, biochemical cure was documented in 20 out of 24 patients. Creatinine levels (mean ± SEM) increased from 72 ± 3 to 80 ± 3 µmol/l (p = 0.0004) and concurrently, estimated GFR decreased from 99 ± 3 to 91 ± 3 ml/min (p = 0.0008). In contrast to creatinine, CysC levels decreased from 0.72 ± 0.02 to 0.68 ± 0.02 mg/l (p = 0.0008). Conclusions: Our study provides strong evidence for discordant effects of GH on creatinine and CysC in patients with acromegaly undergoing transsphenoidal surgery, thus identifying another hormone that influences CysC independent of renal function.

Predictive value of elevated cystatin C in patients undergoing primary angioplasty for ST-elevation myocardial infarction

ObjectivesThe prognostic value of cystatin C (CysC) has been documented in patients with acute coronary syndrome without ST-segment elevation. However, its value in acute ST-segment elevation myocardial infarction (STEMI) remains unclear. The aim of this study was to evaluate the prognostic value of CysC in patients with STEMI undergoing primary percutaneous coronary intervention (PCI). MethodsWe prospectively enrolled 475 consecutive STEMI patients (mean age 55.6 ± 12.4 years, 380 male, 95 female) undergoing primary PCI. The study population was divided into tertiles based on admission CysC values. The high CysC group (n = 159) was defined as a value in the third tertile (>1.12 mg/L), and the low CysC group (n = 316) included those patients with a value in the lower two tertiles (≤1.12 mg/L). Clinical characteristics and in-hospital and one-month outcomes of primary PCI were analyzed. ResultsThe patients of the high CysC group were older (mean age 62.8 ±13.1 vs. 52.3±10.5, P < .001). Higher in-hospital and 1-month cardiovascular mortality rates were observed in the high CysC group (9.4% vs. 1.6%, P < .001 and 14.5% vs. 2.2%, P < .001, respectively). In Cox multivariate analysis; a high admission CysC value (>1.12 mg/L) was found to be a powerful independent predictor of one-month cardiovascular mortality (odds ratio, 5.3; 95% confidence interval, 1.25-22.38; P = .02). ConclusionsThese results suggest that a high admission CysC level was associated with increased in-hospital and one-month cardiovascular mortality in patients with STEMI undergoing primary PCI.

Serum cystatin C level is a useful marker for the evaluation of renal function in patients with cirrhotic ascites and normal serum creatinine levels

Background/AimsSeveral studies suggested that serum cystatin C (CysC) is more useful than serum creatinine (Cr) for the assessment of renal function in patients with liver cirrhosis. This study evaluated the clinical significance of CysC in patients with cirrhotic ascites and normal Cr level.MethodsWe enrolled patients with cirrhotic ascites and a normal serum Cr level (<1.2 mg/dL). GFR was measured by 99mTc-DTPA renal scan. Serum Cr, CysC, and Cr clearance (CCr) were measured on the same day. Significant renal impairment and severe renal impairment were defined as GFR <60 mL/min and GFR <30 mL/min, respectively.ResultsEighty-nine patients with cirrhotic ascites were enrolled in the study (63 men and 26 women; age, 55±11 years). Forty-seven (52.8%) and 42 (47.2%) patients were in Child-Pugh grade B and C, respectively. Serum Cr and CysC levels and GFR were 0.8±0.2 mg/dL, 1.1±0.3 mg/L, and 73.4±25.5 mL/min, respectively. Significant and severe renal impairment were noted in 28 (31.5%) and 2 (2.2%) patients, respectively. GFR was well correlated with serum Cr, CysC, and e-GFRMDRD, while it was not correlated with e-GFRC&G. In multivariate analysis, only CysC was significantly correlated with GFR (β, 45.620; 95% CI, 23.042-68.198; P<0.001). Serum CysC level was the only independent predictor for significant renal impairment.ConclusionsSignificant renal dysfunction was not rare in patients with cirrhotic ascites, even their serum Cr level is normal. Serum CysC is a useful marker for detecting significant renal dysfunction in these patients.

Serum cystatin C level is a good prognostic marker in patients with cirrhotic ascites and normal serum creatinine levels

Serum creatinine (Cr) is not a reliable marker for early detection of renal dysfunction in patients with cirrhotic ascites. Several reports have suggested that cystatin C (CysC) is more sensitive than Cr for detecting reduced renal function in these patients. This study evaluated the clinical significance of CysC in patients with cirrhotic ascites and a normal serum Cr level. We enrolled patients with ascites and a normal serum Cr level (<1.2 mg/dl). Liver function tests, international normalized ratio (INR) and serum Cr and CysC levels were measured on the same day for all patients. CysC levels were measured using the automated latex-enhanced immunonephelometric method. The endpoint of follow-up was the development of hepatorenal syndrome (HRS) or mortality. Seventy-eight patients with cirrhotic ascites were enrolled in the study (58 men and 30 women; age, 53+/-11 years). The underlying liver diseases in these patients were chronic hepatitis B (37%), chronic hepatitis C (4%), alcoholic liver disease (53%) and others (6%). Forty-six (59%) and 32 (41%) patients were in Child-Pugh classes B and C respectively. HRS developed in 14 patients during the follow-up period (349+/-241 days), with cumulative incidences of 10.2% and 20.4% at 6 and 12 months respectively. The CysC level was the only independent predictive factor for HRS. Twenty-three patients died during the follow-up period. CysC level and INR were independent factors for predicting mortality. Serum CysC level is a good marker for predicting HRS and survival in patients with cirrhotic ascites and a normal Cr level.