The Association of Patent Ductus Arteriosus with Inflammation: A Narrative Review of the Role of Inflammatory Biomarkers and Treatment Strategy in Premature Infants

Correlation between the Closure Time of Patent Ductus Arteriosus in Preterm Infants and Long-Term Neurodevelopmental Outcome

In patent ductus arteriosus (PDA) in preterm infants, the relationship between treatment timing and long-term developmental prognosis remains unclear. The purpose of this study was to clarify the relationship between the age in days when ductus arteriosus closure occurred and long-term development. Preterm infants with a birth weight of less than 1500 g who were admitted to our NICU over a period of 9 years (2011-2019) and were diagnosed with PDA were included. A new version of the K-type developmental test for corrected ages of 1.5 and 3 years was used as an index of development. The relationship between the duration of PDA and the developmental index was evaluated using Pearson's correlation coefficient, and multiple regression analysis was performed. Development quotient (DQ) at the ages of 1.5 and 3 years showed a correlation with the PDA closure date and the standard deviation (SD) value of the term birth weight. Multiple regression analysis showed a positive correlation of the DQ at 1.5 and 3 years with the SD value of the term birth weight and a negative correlation with the PDA closure date. In addition, a stronger correlation was found in the "posture/motor" sub-item at 3 years. On the other hand, the analysis including preterm infants without PDA showed that preterm infants with PDA closure on the 6th day or later after birth had a significantly lower 3-year-old DQ than preterm infants with a PDA exposure within 5 days. In conclusion, it is suggested that the decrease in cerebral blood flow due to PDA in preterm infants has an adverse effect on long-term neurodevelopment. Appropriate interventions, including surgical treatment for PDA in preterm infants without delay, ideally within 5 days of birth, may be effective in improving the developmental prognosis.

Closing the Gap: Investigation of Various Approaches in the Management of Patent Ductus Arteriosus

In preterm newborns with extremely low birth weights, patent ductus arteriosus (PDA), which is defined as a remnant connection between the aorta and pulmonary artery after 72 hours of birth, is frequently linked to substantial morbidity and mortality. If left untreated, a hemodynamically significant PDA (hsPDA) increases the risk for bronchopulmonary dysplasia, necrotizing enterocolitis, and intraventricular hemorrhage among other morbidities, and can even lead to death. While instances of patent ductus arteriosus (PDA) resolving on their own are frequent, the primary approach for managing PDA closure in premature infants involves pharmacological interventions, commonly utilizing indomethacin, ibuprofen, or paracetamol. However, with these pharmacological treatment options, there is an increased risk of renal toxicity, gastrointestinal bleeding, and reopening of PDA among other complications. If pharmacological interventions are not successful or contraindicated, PDA can be closed via transcatheter closure or surgical ligation. As with any medically invasive procedure, it is not without risks and can lead to long-term complications. This review explores the different management options and the benefits and outcomes of conservative management vs. active management in order to get one step closer to standardizing the treatment for PDA. With so much controversy surrounding the best management option, there is a lack of evidence to support one treatment method superior to the other in reducing overall mortality, and this needs to be explored further.

Melatonin as a Therapy for Preterm Brain Injury: What Is the Evidence?

Despite significant improvements in survival following preterm birth in recent years, the neurodevelopmental burden of prematurity, with its long-term cognitive and behavioral consequences, remains a significant challenge in neonatology. Neuroprotective treatment options to improve neurodevelopmental outcomes in preterm infants are therefore urgently needed. Alleviating inflammatory and oxidative stress (OS), melatonin might modify important triggers of preterm brain injury, a complex combination of destructive and developmental abnormalities termed encephalopathy of prematurity (EoP). Preliminary data also suggests that melatonin has a direct neurotrophic impact, emphasizing its therapeutic potential with a favorable safety profile in the preterm setting. The current review outlines the most important pathomechanisms underlying preterm brain injury and correlates them with melatonin's neuroprotective potential, while underlining significant pharmacokinetic/pharmacodynamic uncertainties that need to be addressed in future studies.

Nutrition of the preterm infant with persistent ductus arteriosus: existing evidence and practical implications

The persistence of a patent ductus arteriosus (PDA) is a common condition in preterm infants with a prevalence inversely proportional to gestational age. PDA is associated with mild-to-severe gastrointestinal complications such as feeding intolerance, gastrointestinal perforation, and necrotizing enterocolitis, which represent a major challenge for the nutritional management in preterm infants. In this context, the Section on Nutrition, Gastroenterology and Metabolism and the Circulation Section of the European Society for Pediatric Research have joined forces to review the current knowledge on nutritional issues related to PDA in preterm infants. The aim of the narrative review is to discuss the clinical implications for nutritional practice. Because there is little literature on postnatal nutrition and PDA in preterm infants, further research with well-designed studies on this topic is urgently needed. Guidelines should also be developed to clearly define the implementation and course of enteral nutrition and the target nutritional intake before, during, and after pharmacologic or surgical treatment of PDA, when indicated. IMPACT: Persistent ductus arteriosus (PDA) is associated with gastrointestinal complications such as feeding intolerance, gastrointestinal perforation, and necrotizing enterocolitis, which pose a major challenge to the nutritional management of preterm infants. In PDA infants, fluid restriction may lead to inadequate nutrient intake, which may negatively affect postnatal growth and long-term health. The presence of PDA does not appear to significantly affect mesenteric blood flow and splanchnic oxygenation after enteral feedings. Initiation or maintenance of enteral nutrition can be recommended in infants with PDA.

Systemic Cytokines in Retinopathy of Prematurity

Retinopathy of prematurity (ROP), a vasoproliferative vitreoretinal disorder, is the leading cause of childhood blindness worldwide. Although angiogenic pathways have been the main focus, cytokine-mediated inflammation is also involved in ROP etiology. Herein, we illustrate the characteristics and actions of all cytokines involved in ROP pathogenesis. The two-phase (vaso-obliteration followed by vasoproliferation) theory outlines the evaluation of cytokines in a time-dependent manner. Levels of cytokines may even differ between the blood and the vitreous. Data from animal models of oxygen-induced retinopathy are also valuable. Although conventional cryotherapy and laser photocoagulation are well established and anti-vascular endothelial growth factor agents are available, less destructive novel therapeutics that can precisely target the signaling pathways are required. Linking the cytokines involved in ROP to other maternal and neonatal diseases and conditions provides insights into the management of ROP. Suppressing disordered retinal angiogenesis via the modulation of hypoxia-inducible factor, supplementation of insulin-like growth factor (IGF)-1/IGF-binding protein 3 complex, erythropoietin, and its derivatives, polyunsaturated fatty acids, and inhibition of secretogranin III have attracted the attention of researchers. Recently, gut microbiota modulation, non-coding RNAs, and gene therapies have shown promise in regulating ROP. These emerging therapeutics can be used to treat preterm infants with ROP.