Urinary uric acid to creatinine ratio as a marker of perinatal asphyxia and its correlation with arterial blood gas values

Abstract

Objective Perinatal asphyxia is a leading cause of neonatal morbidity and mortality in developing countries. Lack of facilities like arterial blood gas analysis in resource limited settings warrants cost effective methods to support the diagnosis of asphyxia. The study objectives were to evaluate the utility of urinary uric acid to creatinine ratio (UA/Cr ratio) as a marker of perinatal asphyxia and to ascertain its correlation with cord blood arterial blood gas values. Methods It was a prospective comparative study where cases and controls were of asphyxiated neonates and normal neonates respectively delivered in a tertiary care medical college hospital from April 2019 to September 2019. Urinary UA/Cr ratio and its correlation with Apgar score was determined. The ability to predict asphyxia was estimated by ROC curve and p<0.05 was considered as statistically significant. Results Data from 38 asphyxiated and 38 normal neonates were analyzed. The mean urinary UA/Cr ratio was higher in the asphyxiated babies. There was negative correlation between urinary UA/Cr ratio and pH, pO2, Apgar scores and positive correlation with pCO2. The urinary UA/Cr ratio had excellent predictive validity for perinatal asphyxia determined by ROC curve. The urinary uric acid /creatinine ratio had sensitivity of 92.11% and specificity was 92.11%. Conclusion Urinary uric acid to creatinine ratio correlated well with the cord blood arterial blood gas values and the Apgar scores. This study showed that there is a significant increase in the urinary UA/Cr ratio in asphyxiated neonates and it can be used as a biochemical marker of perinatal asphyxia.