Renal effects of ibuprofen for the treatment of patent ductus arteriosus in premature infants

Management of Acute Kidney Injury in Extremely Low Birth Weight Infants

Acute kidney injury (AKI) is a common problem in the neonatal intensive care unit (NICU). Neonates born at <1,000 g (extremely low birth weight, ELBW) are at an increased risk of secondary associated comorbidities such as intrauterine growth restriction, prematurity, volume restriction, ischaemic injury, among others. Studies estimate up to 50% ELBW infants experience at least one episode of AKI during their NICU stay. Although no curative treatment for AKI currently exists, recognition is vital to reduce potential ongoing injury and mitigate long-term consequences of AKI. However, the definition of AKI is imperfect in this population and presents clinical challenges to correct identification, thus contributing to under recognition and reporting. Additionally, the absence of guidelines for the management of AKI in ELBW infants has led to variations in practice. This review summarizes AKI in the ELBW infant and includes suggestions such as close observation of daily fluid balance, review of medications to reduce nephrotoxic exposure, management of electrolytes, maximizing nutrition, and the use of diuretics and/or dialysis when appropriate.

Oral ibuprofen promoted cholestatic liver disease in very low birth weight infants with patent ductus arteriosus

OBJECTIVES

Hemodynamically significant patent ductus arteriosus (hsPDA) in very low birth weight (VLBW) infants is routinely treated in many countries with oral ibuprofen. This study retrospectively assessed whether the risk of cholestatic liver disease (CLD) increased due to oral ibuprofen administration in VLBW infants.

METHODS

A total of 122 VLBW preterm infants (26∼32 weeks, birth weight<1500g) diagnosed with patent ductus arteriosus (PDA) admitted to our neonatal intensive care unit (NICU) between September 2016 to August 2018 were included. Sixty-four infants were diagnosed with hs-PDA and received ibuprofen treatment. VLBW infants with PDA untreated with ibuprofen served as controls. Soybean oil and fat emulsions were routinely added to parenteral nutrition (PN). Once CLD was diagnosed, the fat emulsions were immediately replaced with multi-oil fat emulsion injections. To assess the independent association of treatment and duration of ibuprofen with CLD and duration of fasting and PN, binary logistic regression or multivariate linear regression analyses were conducted, adjusting for major confounders (birth weight, gestational age, Clinical Risk Index for Babies, and cholestasis-associated risk factors).

RESULTS

The duration of PN increased due to ibuprofen treatment for 6.559 days (95% CI: 1.769, 11.349; P=0.008), and the risk of prolonged fasting (cutoff>5 days) might have increased due to ibuprofen treatment (OR: 3.043, 95% CI: 0.965, 9.594; P=0.057). Furthermore, CLD was influenced by ibuprofen treatment (OR: 6.730; 95% CI: 1.279, 35.41; P=0.024), early thrombocytopenia 7 days postnatal (OR: 6.996; 95% CI: 1.769, 27.658; P=0.004), and late onset sepsis (OR: 6.976; 95% CI: 1.561, 31.169; P=0.011). Further analysis adjusting for cholestasis-associated risk factors revealed that CLD was influenced by the duration of ibuprofen treatment (OR: 2.864; 95% CI: 1.104, 7.422; P=0.030), Platlets counts 7 days postnatal (OR: 0.971; 95% CI: 0.950, 0.994; P=0.013), and duration of antibiotics (OR: 1.134; 95% CI: 1.002, 1.282; P=0.046).

CONCLUSIONS

This retrospective study indicated oral ibuprofen duration-dependently increased the risk of CLD in VLBW infants with PDA, and early thrombocytopenia served as the critical risk factor.

Developmental Programming of Renal Function and Re-Programming Approaches

Chronic kidney disease affects more than 10% of the population. Programming studies have examined the interrelationship between environmental factors in early life and differences in morbidity and mortality between individuals. A number of important principles has been identified, namely permanent structural modifications of organs and cells, long-lasting adjustments of endocrine regulatory circuits, as well as altered gene transcription. Risk factors include intrauterine deficiencies by disturbed placental function or maternal malnutrition, prematurity, intrauterine and postnatal stress, intrauterine and postnatal overnutrition, as well as dietary dysbalances in postnatal life. This mini-review discusses critical developmental periods and long-term sequelae of renal programming in humans and presents studies examining the underlying mechanisms as well as interventional approaches to "re-program" renal susceptibility toward disease. Clinical manifestations of programmed kidney disease include arterial hypertension, proteinuria, aggravation of inflammatory glomerular disease, and loss of kidney function. Nephron number, regulation of the renin-angiotensin-aldosterone system, renal sodium transport, vasomotor and endothelial function, myogenic response, and tubuloglomerular feedback have been identified as being vulnerable to environmental factors. Oxidative stress levels, metabolic pathways, including insulin, leptin, steroids, and arachidonic acid, DNA methylation, and histone configuration may be significantly altered by adverse environmental conditions. Studies on re-programming interventions focused on dietary or anti-oxidative approaches so far. Further studies that broaden our understanding of renal programming mechanisms are needed to ultimately develop preventive strategies. Targeted re-programming interventions in animal models focusing on known mechanisms will contribute to new concepts which finally will have to be translated to human application. Early nutritional concepts with specific modifications in macro- or micronutrients are among the most promising approaches to improve future renal health.

Longitudinal assessment of renal size and function in extremely low birth weight children at 7 and 11 years of age

BACKGROUND

There are a lack of studies describing a longitudinal association between preterm delivery and renal complications later in life. We assessed renal size and function in preterm infants born with extremely low birth weight (ELBW) during 4 years of follow-up, comparing these parameters to age-matched children born full term (term controls).

METHODS

The results of selected renal laboratory tests [levels of cystatin C, creatinine, blood urea nitrogen (BUN)] and of renal ultrasound evaluations were compared between the ELBW group and the term control group at age 7 and 11 years.

RESULTS

The study population consisted of 64 children born with ELBW (ELBW children) who had been recruited at birth and 36 children born at term (term children) who took part in both follow-up assessments. Renal ultrasound examination revealed a significantly smaller renal volume in the 7- and 11-year-old ELBW children compared to the term controls [right kidney volume: 50.8 vs. 61.2 ml/m(2), respectively, at 7 years (p <0.01) and 51.4 vs. 58.2 ml/m(2), respectively, at 11 years (p <0.01); left kidney volume: 51.4 vs. 60.3 ml/m(2), respectively, at 7 years (p <0.01) and 55.2 vs. 60.7 ml/m(2), respectively, at 11 years (p = 0.02)]. Renal function in ELBW children was also affected. Serum cystatin C levels were significantly higher in ELBW children than in the controls at 7 years of age, and this difference remained statistically significant at 11 years of age [0.63 vs. 0.59 mg/l, respectively, at 7 years (p = 0.02) and 0.72 vs. 0.61 mg/l, respectively, at 11 years (p = 0.01)]. Six ELBW children also had elevated cystatin C levels (0.97-1.11 mg/l) at 11 years of age. Cystatin C levels were within normal range in the ELBW children at age 7 years and in term children in both follow-up studies. BUN levels were higher in ELBW children at the age of 11 years (4.49 vs. 4.15 mmol/l; p = 0.028).

CONCLUSION

Continued follow-up of these patients will reveal whether the observed worsening in renal function will persist into adulthood.

Laboratory blood tests useful in monitoring renal function in neonates

It is important to monitor renal function in the neonate, especially in premature infants where nephrogenesis is still in process upon birth. The kidneys are responsible for maintaining homeostasis in the extracellular environment by preventing overaccumulation of waste products and electrolytes. This review describes developmental physiology of the renal system as well as laboratory testing to monitor renal function and glomerular filtration in neonates. Drugs that may affect renal function in infants are also discussed.

Treatment of patent ductus arteriosus (PDA) using ibuprofen: renal side-effects in VLBW and ELBW newborns

OBJECTIVES

This study aims to determine whether or not treatment of preterm neonates with PDA using IV ibuprofen can impair renal function and in what range of birth weights and gestational ages the risk of major renal side-effects due to ibuprofen is highest.

METHODS

134 preterm newborns with PDA were enrolled and randomized to receive either placebo or a 3-day-course (10, 5 and 5 mg/kg) of IV ibuprofen. 67 newborns (mGA: 27(+3) w and mBW: 989 g) with PDA received ibuprofen.

RESULTS

Subdividing the infants according to BW and to GA, the values of creatinine and BUN were only significantly higher than initial values at the end of the therapy in newborns with a BW ≤1000 g and/or GA ≤26 weeks. Renal impairment is greater the lower the weight and gestational age of the infant at birth.

CONCLUSIONS

Ibuprofen significantly impairs renal function in preterm infants with a GA ≤26 weeks and/or in ELBW neonates, while it may be considered safe for infants with a BW >1000 g and/or GA >26 weeks. Thus, before starting therapy with IV ibuprofen, it is essential to take into account the BW and GA of newborns and the effective need for treatment from the point of view of the ratio of risks to benefits, due to its substantial renal side-effects.

Preterm birth and the kidney: implications for long-term renal health

Although the majority of preterm neonates now survive infancy, there is emerging epidemiological evidence to demonstrate that individuals born preterm exhibit an elevated risk for the development of hypertension and renal impairment later in life, thus supporting the developmental origins of health and disease hypothesis. The increased risk may potentially be attributed to a negative impact of preterm birth on nephron endowment. Indeed, at the time when most preterm neonates are delivered, nephrogenesis in the kidney is still ongoing with the majority of nephrons normally formed during the third trimester of pregnancy. A number of clinical studies have provided evidence of altered renal function during the neonatal period, but to date there have been limited studies describing the consequences of preterm birth on kidney structure. Importantly, studies in the preterm baboon have shown that nephrogenesis is clearly ongoing following preterm birth; however, the presence of abnormal glomeruli (up to 18% in some cases) is of concern. Similar glomerular abnormalities have been described in autopsied preterm infants. Prenatal and postnatal factors such as exposure to certain medications, hyperoxia and intrauterine and/or extrauterine growth restriction are likely to have a significant influence on nephrogenesis and final nephron endowment. Further studies are required to determine the factors contributing to renal maldevelopment and to identify potential interventional strategies to maximize nephron endowment at the start of life, thereby optimizing long-term renal health for preterm individuals.

Should we definitively abandon prophylaxis for patent ductus arteriosus in preterm new-borns?

Although the prophylactic administration of indomethacin in extremely low-birth weight infants reduces the frequency of patent ductus arteriosus and severe intraventricular hemorrhage, it does not appear to provide any long-term benefit in terms of survival without neurosensory and cognitive outcomes. Considering the increased drug-induced reduction in renal, intestinal, and cerebral blood flow, the use of prophylaxis cannot be routinely recommended in preterm neonates. However, a better understanding of the genetic background of each infant may allow for individualized prophylaxis using NSAIDs and metabolomics.

Therapeutic closure of the ductus arteriosus: benefits and limitations

Patency of the ductus arteriosus (PDA), a common complication of preterm birth, has been associated to increased risk for intraventricular cerebral hemorrhage, necrotizing enterocolitis, bronchopulmonary dysplasia and death. Consequently, prophylactic or curative treatment has been advocated before the critical left-to-right shunting occurs. A host of studies has shown that both pharmacological agents and surgical closure are effective in closing the ductus arteriosus in premature infants. Indomethacin has long been the drug of choice. However, renal and cerebral haemodynamic side effects have been frequently reported. Strategies to minimise adverse effects of indomethacin, such as the association with frusemide, dopamine or the use of low-dose prolonged treatment with indomethacin have failed or shown partial benefit. Other NSAIDs have been investigated. But either the profile of adverse effects was unfavourable, as in the case of mefenamic acid, or their efficacy was less than that of indomethacin for PDA closure. More recently, ibuprofen has been proposed for the treatment of PDA as it was shown to induce less adverse effects on cerebral blood flow, intestinal and renal hemodynamics, while retaining similar efficacy to indomethacin. However, since renal perfusion, GFR and diuresis in early neonatal life strongly depend on the vasodilator effects of PGs on the afferent glomerular arterioles, ibuprofen, as other COX-inhibitors may not be exempt of some renal undesirable effects. While numerous studies have shown that PDA is a risk factor associated with immaturity and with increased incidence of complications of preterm birth, including broncho-pulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis and death, there is little evidence that such association is causative. Moreover, still little evidence exists from even recent randomized controlled trials that the pharmacological closure of PDA benefits to premature infants in terms of clinically significant short-term or medium-term outcomes, beyond a positive effect on DA patency. The use of COX-inhibitors for the prophylaxis or closure of PDA during the first hours or days of life should thus be cautious and based on an individual evaluation of benefit and risk. There is need of a randomized, placebo-controlled trials designed to assess the benefits in terms of mortality and morbidity outcomes of an early, or even very early pharmacological closure of PDA in extremely low gestational age infants.

Safety and effectiveness of indomethacin versus ibuprofen for treatment of patent ductus arteriosus

We compared the rates of medical closure of patent ductus arteriosus (PDA) and complications (renal dysfunction, necrotizing enterocolitis, spontaneous intestinal perforation, and intraventricular hemorrhage) between infants treated with indomethacin and infants treated with ibuprofen. We performed a retrospective comparative cohort study of infants treated with indomethacin or ibuprofen for symptomatic PDA at Duke University Medical Center between November 2005 and November 2007. We identified 65 infants who received indomethacin and 57 who received ibuprofen. The rate of survival without surgical ductal ligation was 62% (40/65) in the indomethacin group and 58% (33/57) in the ibuprofen group (p = 0.71). The rate of the composite of complications (death, necrotizing enterocolitis, or intestinal perforation) was 40% (26/65) in the indomethacin group and 32% (18/57) in the ibuprofen group (p = 0.35). There was no significant difference between groups in elevation of serum creatinine during treatment. In clinical practice, ibuprofen appears to be as effective as indomethacin for closure of patent ductus arteriosus with similar complication rates. The decision to use one agent over the other should be based on dose schedule preference and the currently published clinical trials until more safety and effectiveness data are available.

Is there an optimal timing for surgical ligation of patent ductus arteriosus in preterm infants?

BACKGROUND

We sought to define the variables associated with hospital outcome in preterm infants with patent ductus arteriosus (PDA) and identify the optimal timing for PDA closure to improve hospital outcome.

METHODS

Included were 201 premature babies (< or = 32 weeks gestational age), from January 2001 to June 2007, with PDA who received primary medical treatment with ibuprofen. Number of ibuprofen cycles, gestational age, body weight, and presence of symptomatic hypotension requiring vasoactive/inotropic drugs were related to hospital outcome, including hospital mortality, presence of necrotizing enterocolitis, acute renal failure, intraventricular hemorrhage, retinopathy and bronchopulmonary dysplasia at week 36. Data were analyzed with a logistic regression model.

RESULTS

Medical treatment was effective in 149 patients (75%), but 52 (25%) required surgical ligation after medical treatment failed. They had younger gestational age (25 weeks [IQR, 24 to 27 weeks] vs 27 weeks [IQR, 25 to 28 weeks], p < 0.0001), lower body weight at birth (730 g [IQR, 595 to 915 g] vs 840 g [IQR, 670 to 1016], p = 0.05), and a higher incidence of symptomatic hypotension (38 of 52 [73%] vs 56 of 149 [38%], p < 0.0001) than patients who responded to ibuprofen. More than two cycles of ibuprofen was significantly associated with an increased risk for bronchopulmonary dysplasia (odds ratio [OR], 2.81; p = 0.03) and acute renal failure (OR, 3.81; p = 0.09).

CONCLUSIONS

The prolonged patency of the ductus arteriosus in preterm infants is related to an increased morbidity. Surgical ligation of PDA is a safe and effective treatment and should be done soon after two complete cycles of ibuprofen, especially in selected patients, to improve clinical outcome.

Factors affecting postnatal changes in serum creatinine in preterm infants with gestational age <32 weeks

OBJECTIVE

The Aim of this study was to investigate maternal and neonatal factors associated with serum creatinine (SeCr) changes in a representative cohort of preterm newborns during their first week of life.

STUDY DESIGN

Retrospective study. All the infants born less than 32 weeks of gestational age (GA) and cared for in our neonatal intensive care unit between January 2001 and December 2005 were eligible for the analysis. Epidemiological data of all mother-infant pairs and neonatal SeCr values were recorded.

RESULT

A total of 652 infants were studied. Multivariate regression analysis showed that the main independent factors associated with high SeCr at day 1 were hypertensive disease of pregnancy (P<0.0001) and advancing hour of life (P<0.0001), with minimal contribution of placental abruption (P<0.05) and higher GA (P<0.05). Lower GA (P<0.0001) and ibuprofen-treated patent ductus arteriosus (PDA; P<0.0001) were the main analyzed factors independently associated with higher SeCr peak (defined as the highest SeCr during the week), with less contribution of respiratory distress syndrome (P<0.01) and early onset infection (P<0.05). In infants with hemodynamically significant PDA (hsPDA) SeCr before ibuprofen administration was higher when compared to GA-matched controls without hsPDA (P< 0.0001).

CONCLUSION

SeCr peak was inversely correlated to GA in preterm infants born less than 32 weeks of GA. Neonatal rather than maternal morbidity affected SeCr peak. In hsPDA, SeCr increase preceded ibuprofen administration.

Oral-ibuprofen-induced acute renal failure in a preterm infant

The side effects of indomethacin for ductal closure in preterm neonates (e.g. increased incidence of necrotizing enterocolitis, decreased cerebral blood volume and transient renal failure) have led clinicians to seek a safer alternative. Intravenous indomethacin and ibuprofen appear to be equally effective for patent ductus arteriosus closure, but oral ibuprofen remains an experimental option with theoretical advantages yet with potential side effects. We herein report a case of transient but severe acute renal failure developing in a preterm infant in whom oral ibuprofen was used and discuss the safety of this drug in relation to its pharmacokinetics.