Urine Uric Acid Creatinine Ratio as a Diagnostic and Prognostic Marker of Neonatal Birth Asphyxia

Abstract

Background: Cerebral hypoxia can result in anaerobic glycolysis which leads to decreased phosphorylase production and increased uric acid which gets excreted in the urine where it can be easily detected. The aim of the study is to assess the utility of urine uric acid creatinine ratio (UA/Cr) as an additional marker of neonatal depression and birth asphyxia and its utility as a potential prognostic indicator for the immediate outcome. Subjects and Methods: It was a case-control study that included 30 newborns born with an APGAR score of less than 7 at 1-min and requiring positive pressure ventilation. Cases were sub-grouped into neonatal depression and birth asphyxia. Newborns with moderate and severe encephalopathy were considered to have an unfavourable outcome. The urine UA/Cr was estimated in both groups. One-way Anova test, Spearman’s rho and Receiver Operating Characteristic curve were used for statistical analysis. Results: The mean differences of urine UA/Cr were statistically significant (p=0.011) in birth asphyxia (3.02 1.34), neonatal depression (2.31 0.81) and controls (2.01 0.69). A significant negative correlation was seen with APGAR at 1-min (r=-0.43; p=0.001) and 5-min (r=-0.52; p=0.001) and umbilical cord blood pH (r= -0.29; p=0.021). The mean difference of UA/Cr between those with unfavorable (3.23 1.49) and favourable (2.14 0.73) outcomes was significant (p=0.006). A ratio 2.85 suggested the unfavourable outcome. Conclusion: The urine UA/Cr is a useful diagnostic and prognostic biomarker in newborns with birth asphyxia.

The Urinary Uric Acid / Cr ratio as a marker of morbidity and mortality of preterm infants: a case—control study

“…Our study showed a significant higher ratio of UUA/ Cr in premature neonates admitted in NICU suffering hypoxia. Several other studies have reached similar results [2,3,6,8,9,[13][14][15][16][17][18][19][20][21]. In the case -control study of Sreekrishna et al on 50 normal neonates and 50 newborn infant with asphyxia, the mean Urinary Uric Acid / Cr ratio in case and control group was 2.8 ± 0.9 and 0.8 ± 0.2 respectively which shows a significant higher ratio in case group (P < 0.001) [2].…”

“…In recent years, some studies have shown that The UUA/Cr ratio may be used as an additional marker for perinatal asphyxia in full-term and preterm infants. Within 24 h of birth, UUA/Cr ratio is a simple, fast, and inexpensive way to diagnose hypoxic episodes of NICU admitted patients compared with other markers such as xanthine, hypoxanthine and ascorbic acid [5][6][7][8][9]. The Urinary Uric Acid / Cr ratio, as a biochemical marker, can support the clinical diagnosis and severity of asphyxia previously determined by the Apgar score.…”