Evaluation of Plasma Amino Acid Levels in Preterm Infants and Their Potential Correlation with Retinopathy of Prematurity

AIM: The aim of this study is to ascertain whether the level of circulating amino acids (aa) is associated with retinopathy of prematurity (ROP). METHODS: This is a randomized controlled study of 55 infants born at gestational age (GA) ≤32 weeks or birth weight (BW) ≤1500 grams. Serum samples were obtained from two groups: Group A comprised of 26 preterm infants with ROP and Group B comprised of 29 preterm infants without ROP. Plasma aa levels were analyzed using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Correlation test and multivariate regression analysis were used to evaluate the relationship between plasma aa levels and variables. RESULTS: The mean serum arginine and glutamine levels were significantly higher, but the mean lysine and aspartic acid levels were significantly lower in Group A, compared to Group B (p = 0.04, p = 0.002, p = 0.029, and p = 0.002, respectively). In multivariate analysis, the mean arginine and lysine levels were significantly associated with the stage of the disease (p = 0.03 and p = 0.01, respectively). No significant differences were determined between the groups in terms of alanine, asparagine, valine, leucine, phenylalanine, tyrosine, serine, proline, citrulline, cysteine, ornithine, tryptophan, methionine, threonine, taurine, and isoleucine amino acids (p > 0.05, respectively). CONCLUSIONS: These results indicate a significant association between high arginine and glutamine, with low lysine and aspartic acid serum concentrations with ROP. Due to higher serum concentrations in ROP, extra arginine-glutamine supplementation in hyperoxic conditions may be unfavorable through pathways involving reactive oxygen, particularly in patients with ROP.