Are low birth weight children predisposed to renal loss of carnitine?

Aim: The plasma homeostasis of both free and esterified carnitines is mostly regulated by renal tubular reabsorption, which may be disturbed in low birth weight children. The aim of study was to check whether disturbances in excretion of l-carnitine (LC) and its main ester, acetyl-carnitine (ALC), may be the result of renal dysfunction in low birth weight children (LBW).Methods: This study included 59 LBW children (2165 g [1490-2440]) and 22 children with normal birth weight as a reference group (3500 g [3275-3650]). Subjects were divided into three groups: 0-3 months, 4-12 months and over 1 year at the time of testing. Urinary levels of carnitine were measured spectrophotometrically.Results: The urine excretion of Free LC, Free LC/cr, Total LC and Total LC/cr. Were significantly higher in 0-3 and 4-12-month old LBW infants study groups when compared to the reference groups. We found statistically significant higher urine excretion of ALC and ALC/cr. in all age groups of LBW infants compared to the reference group. There was a negative correlation between birth weight and free LC/cr. (r= -0.3, p < .05), Total LC/cr. (r= -0.34, p < .05), and ALC/cr. (r= -39, p < .05), and in the children >12-month-old strong negative correlation between eGFR and free LC/cr. (r= -0.6, p < .05), Total LC/cr. (r= -0.61, p < .05), ALC/cr. (r= -0.61, p < .05.)Conclusion: Higher urine excretion of both LC and ALC and its negative correlation with birth weight and eGFR may reflect some degree of renal dysfunction in LBW infants.

Is symmetric dimethylarginine a sensitive biomarker of subclinical kidney injury in children born with low birth weight?

OBJECTIVE: The aim of this study was to investigate if Symmetric Dimethylarginine (SDMA) is a sensitive biomarker of renal function and may predict subclinical kidney injury in low birth weight (LBW) children. METHODS: We studied 68 LBW children and 20 children as reference group. An enzyme-linked immunosorbent assay was used to measure serum SDMA and Cystatin C (Cys C). RESULTS: SDMA levels were higher in study groups compared to reference groups. There was a strong correlation between SDMA and Cys C, also SDMA negatively correlated with eGFR. CONCLUSION: Elevated SDMA concentration may play an important role in pathogenesis of chronic kidney disease.