Cystatin C as a predictor of acute renal damage after radical surgical treatment in patients with muscle-invasive bladder cancer

Purpose of the study. To assess the clinical and prognostic significance of serum and urinary cystatin C (uCys-C and sCys-C) in patients undergoing radical cystectomy (RC) in relation to AKI.Patients and methods. In this prospective study, uCys-C and sCys-C levels were measured during the first week after undergoing RC in a heterogeneous group of patients undergoing RC (n=186), mean age 59.5±11.4 years. The observation period of the patients was 6 months. The diagnosis of AKI that developed within the first week after surgery was based on the KDIGO criteria.Results. Of the 186 examined patients, 43 developed AKI according to generally accepted criteria. During the follow-up period, no patient required renal replacement therapy. AKI patients had a longer hospital stay (22.4±22.9 versus 13.0±4.1). The sCys-C levels were significantly associated with the occurrence of AKI and CKD in the long-term postoperative period and had an area under the ROC curve of 0.76 and 0.81, respectively, for predicting severe outcomes. At an optimal cut-off value of 161.17 ng/ml, sCys-C showed a sensitivity of 65 % and a specificity of 58 % for predicting AKI. The greatest increase in the concentration of sCys-C was detected 6-12 hours after surgery, followed by a decrease in the long-term follow-up.Conclusion. Peak sCys-C levels are associated with AKI and independently predict the development of AKI in patients after RC and the onset of CKD within 6 months.

Evaluation of serum and urine neutrophil gelatinase-associated lipocalin and cystatin C as biomarkers of acute kidney injury in horses

Introduction Diagnosis of acute kidney injury (AKI) in horses is difficult at the subclinical stage, due to nonspecific clinical signs. The aim of this study was to evaluate the concentrations of selected serum and urinary biomarkers in healthy horses, horses at risk of AKI, and those with clinical AKI. Material and Methods Thirty healthy horses, 30 horses at risk of AKI and 11 horses with clinical AKI and azotaemia were included in the study. Serum and urinary neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C were measured using commercially available enzyme immunoassay tests. Results The median and (in parentheses) first and third quartile concentrations of selected biomarkers in healthy horses, horses at risk of AKI and horses with AKI were respectively as follows: serum cystatin C – 0.25 (0.19–0.37), 0.23 (0.15–0.37) and 0.61 (0.37–1.13) mg/L; serum NGAL – 50.5 (38.8–58.8), 51.1 (40.4–66.9) and 98.1 (59.4–128.2) ng/mL; urinary NGAL – 20.7 (17.9–24.5), 32.3 (32.7–55.8) and 36.6 (26.8–89.9) ng/mL; and urinary cystatin C – 0.1 (0.07–0.13), 0.13 (0.1–0.2) and 0.34 (0.22–0.37) mg/L. There were significant differences in the concentration of all biomarkers between the healthy and AKI-affected horses. Conclusion Horses with AKI all had biomarker concentrations higher than the healthy horses. None of the biomarkers made azotaemia recognisable in all affected horses. The obtained results indicate the need to create a serum and urinary biomarker panel to detect AKI.

Acute Kidney Injury in Critically Ill Patients

Abstrak: Gagal ginjal akut (GGA) sering ditemukan dalam praktek klinik namun diagnosisnya dapat tertunda oleh karena keterbatasan alat diagnostik. Dewasa ini, kriteria diagnostik RIFLE, AKIN, dan KDIGO untuk menilai adanya GGA dan keparahannya dianggap tidak cukup untuk menggambarkan kompleksitas sindrom GGA. Proteinuria dan mikroalbuminuria yang merupa-kan marker klasik progresi cedera ginjal kronik, telah dipergunakan dan divalidasi untuk progresi GGA ke CKD. Kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), dan urinary cystatin C dapat berperan dalam memrediksi pemulihan ginjal. Indikasi biopsi ginjal pada pasien kritis ialah gangguan ginjal yang tidak jelas atau progresi CKD dengan hematuria glomerulus dan proteinuria lebih dari 1 gram per hari, manifestasi ginjal dari penyakit sistemik yang mengancam nyawa, kecurigaan penolakan akut atau kronik dari ginjal transplan. Mempertahankan hemodinamik yang adekuat seharusnya bermanfaat dalam pence-gahan onset atau perburukan GGA, namun kelebihan cairan harus dihindari. Sampau saat ini penentuan saat inisiasi acute renal replacement therapy (ARRT) masih kontroversial, demikian pula nilai ambang spesifik untuk memulainya belum sepenuhnya disepakati. Kata kunci: gagal ginjal akut; penyakit kritis' laju filtrasi glomerulus (LFG) Abstract: Acute kidney injury (AKI) is a common problem in clinical practice, but its diagnosis could be delayed due to the inherent limitation of current diagnostic tools. Current practice suggests that RIFLE, AKIN, and KDIGO diagnostic criteria used to assess the presence of AKI and its severity are insufficient to illustrate the complexity of the AKI syndrome. Proteinuria and micro-albuminuria, classical markers of chronic kidney disease (CKD) progression, have been used and validated for the progression of AKI to CKD. Kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), and urinary cystatin C could play a role in prediction of renal recovery. Indication of renal biopsy in critically ill patients are unexplained renal impairment or progression of CKD with both glomerular hematuria and proteinuria more than 1 gr per day, renal manifestations of life threathening systemic disease, suspected acute or chronic rejection of a transplanted kidney. The maintenance of adequate hemodynamics should be beneficial in preventing the onset or the worsening of AKI, but fluid overload should be avoided. Timing of acute renal replacement therapy (ARRT) initiation is still controversial, moreover, specific thresholds for starting are still unclear.Keywords: acute kidney injury (AKI); critically ill; glomerular filtration rate (GFR)

Clusterin as a New Marker of Kidney Injury in Children Undergoing Allogeneic Hematopoietic Stem Cell Transplantation—A Pilot Study

Background and aims: The markers of renal damage defining subclinical AKI are not widely used in children undergoing allogeneic hematopoietic stem cell transplantation (alloHSCT). The aim of the study was to evaluate serum and urinary clusterin as indices of kidney injury after alloHSCT in relation to damage (kidney injury molecule (KIM)-1) and functional (cystatin C) markers. Material and methods: Serum and urinary clusterin, KIM-1 and cystatin C concentrations were assessed by ELISA in 27 children before alloHSCT, 24 h, 1, 2, 3 and 4 weeks after alloHSCT and in controls. Results: All parameters were significantly higher in HSCT patients compared to controls even before the transplantation. The serum concentrations increased after HSCT and this rising trend was kept until the third (clusterin) or 4th (KIM-1, cystatin C) week. Urinary clusterin and KIM-1 were elevated until the third week and then decreased yet remained higher than before HSCT. Urinary cystatin C has risen from the second week after HSCT and decreased after the third week but was still higher than before alloHSCT. Conclusions: The features of kidney injury are present even before alloHSCT. Clusterin seems useful in the assessment of subclinical AKI and may become a new early marker of sublethal kidney injury in children.