The Effect of Blood on the Protein to Creatine Ratio during Pregnancy

Résumé fourni par la source

The protein-creatinine (PC) ratio is a laboratory value utilized frequently for the diagnosis of pre-eclampsia. Our study looks at the effects of blood on the PC ratio. Urine can be contaminated with blood for multiple etiologies common in pregnancy. We collected urine and blood samples from pregnant patients of at least 20 weeks’ gestation. Patients were screened to exclude baseline proteinuria, defined as a prior PC ratio < 0.3 within 24 hours prior to enrollment. The threshold of 0.3 mg/mg is based on prior validation studies demonstrating correlation with ≥300 mg of protein in a 24-hour urine collection. A urinalysis and PC ratio were completed on samples. Our study found that urine contaminated with blood, ranging from microscopic to visible hematuria, will falsely elevate the PC ratio. Straight catheterization may be required for diagnosing preeclampsia in an obstetric patient when there is concern for blood contamination. These findings support cautious interpretation of PC ratios in visibly bloody specimens and consideration of repeat sampling when contamination is suspected.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.