The Urinary Uric Acid/Creatinine Ratio is An Adjuvant Marker for Perinatal Asphyxia.

Objective: To assess the urinary uric acid/creatinine ratio (UA/Cr) in relation to Apgar score and cord blood gas analysis in identification of perinatal asphyxia and to define the cutoff values.

Design: case control study.

Setting: The newborns admitted in the department of pediatrics and NICU of Mediciti Institute of Medical Science, Ghanpur, Medchal mandal, Telangana from May-July 2011 were enrolled.

Participants/patients: The study was conducted on 31 (18 males, 13 females) controls and 18 (12males, 6 females) asphyxiated neonates.

Outcome Measures: 5ml of arterial cord blood of newborn collected at the time of birth and spot urine samples were collected within 24-72 hours of life. Cord blood gas analysis were done immediately and Urinary uric acid was measured by modified Uricase method, urinary creatinine by modified kinetic Jaffe's reaction.

Results: The mean urinary uric acid and creatinine ratio (2.58± 0.48 vs 1.89 ± 0.59) is significantly higher in Asphyxiated group than in the control group. The umbilical cord blood pH had significant positive correlation with 1 minute Apgar score (r= 0.41, p=0.003), 5 minute Apgar (r= 0.44, p=0.002), while urinary UA/Cr ratio had significant negative correlation with cord blood pH (r= -0.63, p=0.002). Urinary UA/Cr ratio with criterion of >2.43 had 80% sensitivity, 87.5% specificity with AUC of 0.84 (p=0.003) had a better predictive value.

Conclusions: Urinary UA/Cr ratio is easy, non-invasive, painless and economical adjuvant parameter with better predictive value for diagnosing perinatal asphyxia with simple diagnostic equipment.