Serum cystatin C is a sensitive early marker for changes in the glomerular filtration rate in patients undergoing laparoscopic surgery

Abstract

OBJECTIVE:Pneumoperitoneum during laparoscopy results in transient oliguria and decreased glomerular filtration and renal blood flow. The presence of oliguria and elevated serum creatinine is suggestive of acute renal injury. Serum cystatin C has been described as a new marker for the detection of this type of injury. In this study, our aim was to compare the glomerular filtration rate estimated using cystatin C levels with the rate estimated using serum creatinine in patients with normal renal function who were undergoing laparoscopic surgery.METHODS:In total, 41 patients undergoing laparoscopic cholecystectomy or hiatoplasty were recruited for the study. Blood samples were collected at three time intervals: first, before intubation (T1); second, 30 minutes after the establishment of pneumoperitoneum (T2); and third, 30 minutes after deflation of the pneumoperitoneum (T3). These blood samples were then analyzed for serum cystatin C, creatinine, and vasopressin. The Larsson formula was used to calculate the glomerular filtration rate based on the serum cystatin C levels, and the Cockcroft-Gault formula was used to calculate the glomerular filtration rate according to the serum creatinine levels.RESULTS:Serum cystatin C levels increased during the study (T1 = T2<T3; p<0.05), whereas serum creatinine levels decreased (T1 = T2>T3; p<0.05). The calculated eGlomerular filtration rate-Larsson decreased, whereas the eGlomerular filtration rate-Cockcroft-Gault increased. There was no correlation between cystatin C and serum creatinine. Additionally, Pearson's analysis showed a better correlation between serum cystatin C and the eGlomerular filtration rate than between serum creatinine and the eGlomerular filtration rate.CONCLUSION:This study demonstrates that serum cystatin C is a more sensitive indicator of changes in the glomerular filtration rate than serum creatinine is in patients with normal renal function who are undergoing laparoscopic procedures.

The ischemic/nephrotoxic acute kidney injury and the use of renal biomarkers in clinical practice

“…It is not secreted by renal tubules and does not vary with gender, race, weight, changes of muscle mass, and nutrition. The half-life of Cystatin C (1.5 h) is three times shorter than that of Creatinine; thus, its serum concentration will rise more rapidly than SCr when GFR decreases [37][38][39][40][41]. But marked albuminuria decreases tubular reabsorption of Cystatin C because albumin is also reabsorbed by megalin-facilitated endocytosis thereby competing with its tubular reabsorption.…”

Biomarcadores No Diagnóstico Precoce Da Injúria Renal Aguda

“…Adicionalmente, o biomarcador deve ser endógeno, não tóxico, filtrado livremente pelo glomérulo e excretado sem alteração pelos rins (LIMA et al, 2014).…”

“…Acredita-se que nenhum dos novos biomarcadores será capaz de satisfazer todos os critérios de exigência, visto que um único marcador sozinho teria que ter acurácia para estimar a TFG e indicar a natureza de injúria renal ao mesmo tempo (LIMA et al, 2014).…”

“…Todas as células nucleadas parecem produzir a cistatina C, uma protease inibidora de 13kDa (DE LOOR et al, 2013) que é filtrada e absorvida pelo receptor megalina, localizado nas células epiteliais tubulares proximais, local de degradação (KOVALINKA, 2014). É removida pelo glomérulo e reabsorvida pelos túbulos renais e então, metabolizada e não volta para a circulação (LIMA et al, 2014). O padrão normal das concentrações urinárias de cistatina C está entre 0,03 a 0,3mg/L e o aumento de cistatina sérica é proporcional à queda na TFG (KEPLA et al, 2013).…”

“…Adicionalmente, estudos recentes mostraram que a cistatina C se eleva precocemente na IRA, fato que pode ser observado em pacientes internados em unidades de tratamento intensivo, após transplante hepático, cirurgia cardíaca, quimioterapia com cisplatina, angiografia cardíaca, após uninefrectomia e na progressão da nefropatia diabética (ABENSUR, 2014). Os valores de cistatina C no soro podem ser afetados pelo sexo, altura, peso, diabetes, uso de corticosteróides, função anormal de tireóide e inflamação sistêmica (LIMA et al, 2014). Constatou-se uma variação de 37% nos valores de referência quando a concentração alterou-se em decorrência de fatores extrarrenais o que pode ter sido um fator complicador na interpretação dos resultados (COBRIN et al, 2013).…”