Urinary [TIMP-2] × [IGFBP-7] for predicting acute kidney injury in patients undergoing orthotopic liver transplantation

Predictive value of urinary cell cycle arrest biomarkers for all cause-acute kidney injury: a meta-analysis

The cell cycle arrest markers tissue inhibitor metalloproteinases-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) have been identified as potential biomarkers of acute kidney injury (AKI) in critically ill adults in intensive care units and cardiac surgery-associated AKI (CSA-AKI). However, the clinical impact on all-cause AKI remains unclear. Here, we report a meta-analysis performed to evaluate the predictive value of this biomarker for all-cause AKI. The PubMed, Cochrane, and EMBASE databases were systematically searched up to April 1, 2022. We used the Quality Assessment Tool for Diagnosis Accuracy Studies (QUADAS-2) to assess the quality. We extracted useful information from these studies and calculated the sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC). Twenty studies with 3625 patients were included in the meta-analysis. The estimated sensitivity of urinary [TIMP-2] × [IGFBP7] in the diagnosis of all-cause AKI was 0.79 (95% CI 0.72, 0.84), and the specificity was 0.70 (95% CI 0.62, 0.76). The value of urine [TIMP-2] × [IGFBP7] in the early diagnosis of AKI was assessed using a random effects model. The pooled positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were 2.6 (95% CI 2.1, 3.3), 0.31 (95% CI 0.23, 0.40), and 8 (95% CI 6, 13), respectively. The AUROC was 0.81 (95% CI 0.78-0.84). No significant publication bias was observed in eligible studies. Subgroup analysis indicated that the diagnostic value was related to the severity of AKI, time measurement, and clinical setting. This study shows that urinary [TIMP-2] × [IGFBP7] is a reliable effective predictive test for all cause-AKI. However, whether and how urinary [TIMP-2] × [IGFBP7] can be used in clinical diagnosis still requires further research and clinical trials.

Novel biomarkers of acute kidney injury in chronic liver disease: Where do we stand after a decade of research?

Acute kidney injury (AKI) is a frequently encountered complication in decompensated chronic liver disease (CLD) with an estimated prevalence of 20%-50% among hospitalized patients. AKI often heralds the onset of a downhill course in the natural history of CLD. Serum creatinine has several limitations as a stand-alone marker of AKI in patients with decompensated CLD. The concept of hepatorenal syndrome, the prototype of AKI in decompensated CLD, has evolved tremendously over recent years. There is emerging evidence of an additional "structural" component in the pathophysiology of hepatorenal syndrome-AKI, which was previously identified as a purely "functional" form of renal impairment. Lacunae in the existent biochemical arsenal for diagnosis and prognosis of AKI have fueled enthusiastic research in the field of novel biomarkers of kidney injury in patients with cirrhosis. The advent of these biomarkers provides a crucial window of opportunity to improve the diagnosis and clinical outcomes of this vulnerable cohort of patients. This review summarizes the dynamic concept of renal dysfunction in CLD and the available literature on the role of novel biomarkers of AKI in assessing renal function, identifying AKI subtypes, and predicting prognosis. There is special emphasis on the renal tubular injury marker, neutrophil gelatinase-associated lipocalin, the most exhaustively studied biomarker of AKI in the CLD population.

Diabetes mellitus is a risk factor of acute kidney injury in liver transplantation patients

BACKGROUND

Diabetes mellitus has become an increasing global health burden with rapid growing prevalence. Patients with diabetes have higher susceptibility to acute kidney injury (AKI). Liver transplantation (LT) predisposes the kidney to injury. However, the association between diabetes and AKI in LT patients remains unclear.

METHODS

We conducted a retrospective cohort study examining risk factors for AKI in patients undergone orthotopic LT. Potential risk factors including baseline estimated glomerular filtration rate (eGFR), the model for end-stage liver disease (MELD) score, diabetes, hypertension and intraoperative blood loss were screened. The primary endpoint was AKI occurrence. Multivariate logistic regression was used to analyze the association between potential risk factors and AKI.

RESULTS

A total of 291 patients undergone orthotopic LT were included in the present study. Among them, 102 patients (35.05%) developed AKI within 5 days after LT. Diabetes was identified as an independent risk factor for AKI. Patients who developed AKI had worse graft function recovery and higher mortality within 14 days after LT compared to those who did not develop AKI. AKI patients with diabetes had a significant decline of eGFR within the first postoperative year, compared with patients who did not develop AKI and who developed AKI but without diabetes.

CONCLUSIONS

Diabetes is an independent risk factor for AKI after orthotopic LT. AKI is associated with delayed graft function recovery and higher mortality in short-term postoperative period. Diabetic patients who developed AKI after LT experience a faster decline of eGFR within the first year after surgery.

Usefulness of the Biomarker TIMP-2•IGFBP7 for Acute Kidney Injury Assessment in Critically Ill Patients: A Narrative Review

OBJECTIVES

To review the clinical usefulness of the biomarker TIMP-2•IGFBP7 in adult, general medical-surgical intensive care unit (ICU) settings.

DATA SOURCES

PubMed (1946 to mid-February 2021) and EMBASE (1947 to mid-February 2021) with bibliographies of retrieved articles reviewed for additional articles.

STUDY SELECTION AND DATA EXTRACTION

Studies evaluating use of the urinary TIMP-2•IGFBP7 assay in adult patients in ICU settings.

DATA SYNTHESIS

Studies published after investigations leading to TIMP-2•IGFBP7 assay approval confirm the appropriateness of considerations discussed in product labeling, such as use of the test within 12 hours of assessment, use of a dichotomous 0.3 (ng/mL)²/1000 cutoff, and use only in combination with other assessments of acute kidney injury (AKI). However, as a biomarker routinely used for early identification of patients at risk for AKI in mixed ICU populations, the additional resources required for TIMP-2•IGFBP monitoring are difficult to justify because of limited data demonstrating usefulness in preventing or ameliorating AKI and its attendant complications.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Biomarkers are potentially useful not only for assessment and diagnosis of AKI, but also for practitioners involved in the management of nephrotoxic medications and medications needing adjustment for decreased kidney function.

CONCLUSIONS

Although there is evidence to suggest that the urinary TIMP-2•IGFBP7 biomarker is helpful in predicting AKI progression in general medical-surgical ICU patients when used within 12 hours of patient assessment in combination with routine testing, including serum creatinine and urine output, there is little evidence that its use leads to improvements in clinically important patient outcomes.

Biomarkers for detecting and improving AKI after liver transplantation: From diagnosis to treatment

Orthotopic liver transplantation (OLT) is a well-established treatment for patients with liver failure. The shortage of donor organs and postoperative complications remain major obstacles for improving patient survival. Among these complications, acute kidney injury (AKI) is one of the most frequent types, contributing to graft loss. The timely detection and reversal of AKI can reduce its adverse influences on graft and patient outcomes. Traditional markers for detecting AKI are often limited with regard to their accuracy and specificity, and the discovery of better AKI markers and therapeutic targets assumes great importance. During past decades, studies directed toward early detection and treatment of AKI in OLT have been available. This review summarizes the evidence of these biomarkers for the prediction, diagnosis, treatment and prognosis stratification of AKI associated with OLT.