Impact of nephrotoxic drugs on urinary biomarkers of renal function in very preterm infants

Advocating for the inclusion of kidney health outcomes in neonatal research: best practice recommendations by the Neonatal Kidney Collaborative

Acute kidney injury (AKI) occurs in nearly 30% of sick neonates. Chronic kidney disease (CKD) can be detected in certain populations of sick neonates as early as 2 years. AKI is often part of a multisystem syndrome that negatively impacts developing organs resulting in short- and long-term pulmonary, neurodevelopmental, and cardiovascular morbidities. It is critical to incorporate kidney-related data into neonatal clinical trials in a uniform manner to better understand how neonatal AKI or CKD could affect an outcome of interest. Here, we provide expert opinion recommendations and rationales to support the inclusion of short- and long-term neonatal kidney outcomes using a tiered approach based on study design: (1) observational studies (prospective or retrospective) limited to data available within a center's standard practice, (2) observational studies involving prospective data collection where prespecified kidney outcomes are included in the design, (3) interventional studies with non-nephrotoxic agents, and (4) interventional studies with known nephrotoxic agents. We also provide recommendations for biospecimen collection to facilitate ancillary kidney specific research initiatives. This approach balances the costs of AKI and CKD ascertainment with knowledge gained. We advocate that kidney outcomes be included routinely in neonatal clinical study design. Consistent incorporation of kidney outcomes across studies will increase our knowledge of neonatal morbidity.

Necrotizing Enterocolitis-Associated Acute Kidney Injury-Transforming the Paradigm

Necrotizing enterocolitis (NEC) is one of the most common conditions requiring emergency surgery in the neonatal intensive care unit and is associated with a septic shock-like state contributing to multiorgan dysfunction. NEC affects 6 to 10% of very low-birth-weight infants and remains a leading cause of death. The occurrence of severe acute kidney injury (AKI) following surgical NEC is a harbinger of multiple morbidities. This review presents current evidence about the clinical impact of NEC-associated AKI on the clinical outcomes. Studies evaluating nephroprotective strategies to prevent AKI and its consequences are greatly needed to improve the postoperative recovery and clinical outcomes in neonates with NEC. Future observational studies and clinical trials in preterm infants with NEC prioritize measuring short-term (AKI) and longer term (chronic kidney disease) kidney outcomes. KEY POINTS: · Severe AKI is common following surgical NEC.. · Severe AKI following NEC is associated with poor clinical outcomes.. · Studies evaluating nephroprotective strategies to prevent AKI and its consequences are needed.. IMPACT: · Severe AKI (stage 2 and 3) occurs in 32.6% of neonates after NEC diagnosis and in 58.7% following surgical NEC diagnosis.. · NEC-associated AKI is associated with severe postoperative course, moderate-to-severe bronchopulmonary dysplasia, surgical complications, brain injury, and longer hospital stay in preterm infants.. · Severity of NEC-associated AKI can be utilized by bedside providers for the prognostication of clinical outcomes in preterm infants..

Gestational age-specific clinical correlates of acute kidney injury in preterm infants with necrotizing enterocolitis

BACKGROUND

To study the gestational age-specific risk factors and outcomes of severe acute kidney injury (AKI) in neonates with necrotizing enterocolitis (NEC).

METHODS

Retrospective cohort study comparing gestational age (GA)-specific clinical data between infants without severe AKI (stage 0/1 AKI) and those with severe AKI (stages 2 and 3 AKI) stratified by GA ≤27 and >27 weeks.

RESULTS

Infants with GA ≤27 weeks had double the rate of severe AKI (46.3% vs. 20%). In infants with GA >27 weeks, male sex, outborn, and nephrotoxic medication exposure were associated with severe AKI. On multivariable logistic regression, in infants with GA ≤27 weeks, surgical NEC (OR 35.08 (CI 5.05, 243.73), p < 0.001) and ostomy (OR 6.2(CI 1.29, 29.73), p = 0.027) were associated with significantly higher odds of severe AKI. Surgical NEC infants with GA >27 weeks and severe AKI were significantly more likely to be outborn, have later NEC onset, need dopamine, and have longer hospitalization (158 days [110; 220] vs.75.5 days [38.8; 105]; p = 0.007 than those with non-severe AKI.

CONCLUSION

In neonates with NEC, surgical intervention was associated with moderate-to-severe AKI in infants with GA ≤27 weeks and with longer hospitalization in infants with GA >27 weeks.

IMPACT

In both cohorts need for surgery, stoma, cholestasis, and mechanical ventilation were associated with severe AKI; however, the infants with GA <27 weeks had twice the risk of severe AKI than GA >27 weeks group. The longer exposure to nephrotoxic medication and referral need were significant risk factors for AKI in GA >27 weeks group. GA-specific kidney protective and monitoring strategies to prevent AKI and its consequences are needed to improve the clinical outcomes in neonates with NEC. Understanding the risk factors and short- and long-term outcomes unique to different GA groups will help inform those strategies.

Overview of Antibiotic-Induced Nephrotoxicity

Drug-induced nephrotoxicity accounts for up to 60% of cases of acute kidney injury (AKI) in hospitalized patients and is associated with increased morbidity and mortality in both adults and children. Antibiotics are one of the most common causes of drug-induced nephrotoxicity. Mechanisms of antibiotic-induced nephrotoxicity include glomerular injury, tubular injury or dysfunction, distal tubular obstruction from casts, and acute interstitial nephritis (AIN) mediated by a type IV (delayed-type) hypersensitivity response. Clinical manifestations of antibiotic-induced nephrotoxicity include acute tubular necrosis (ATN), AIN, and Fanconi syndrome. Given the potential nephrotoxic effects of antibiotics on critically ill patients, the use of novel biomarkers can provide information to optimize dosing and duration of treatment and can help prevent nephrotoxicity when traditional markers, such as creatinine, are unreliable. Use of novel kidney specific biomarkers, such as cystatin C and urinary kidney injury molecule-1 (KIM-1), may result in earlier detection of AKI, dose adjustment, or discontinuation of antibiotic and development of nonnephrotoxic antibiotics.