Correlation of 12 hour urine protein and the urinealbümin/creatinin ratio with 24 hour urinary protein value in thediagnosis of preeclampsia

Objective: To asses the association between protein/creatinine ratio (PCR), albumin/creatinine ratio (ACR) in spot urine and protein excretion in 24-hour urine sample of the patients evaluated for preeclampsia (PE), and to review the value of such association for prediction of proteinuria in the patients with PE. Furthermore, 12-hour urine collection technique instead of 24-hour urine collection shall be analysed in the present study. Material and Method: The study was carried out with 70 pregnant women (30 patients with PE, 40 pregnant women for control). Demographic features, previous and current pregnancy characteristics, high blood pressure statys, blood analyses, urine culture results and urine protein quantities of the case and control groups were reviewed and compared. The association of PCR and ACR in spot urine sample with protein quantity in 24-hour urine, primary and secondary 12-hour urine samples were reviewed. Findings: There was not any difference detected between the case and control groups for age, education level, co-morbidity, insulin use, smoking habit, risk factor, antihypertensive use, anti-aggregant use, gestational week, conception method, gravida, parity, abort state, number of live births, urine culture results, the week that high blood pressure was detected and blood pressure levels, and quantitative protein levels in urine (p>0.05). Use of magnesium sulphate (MgSO4) and incidence of oedema were higher in the case group (p<0.05). No difference was detected between the case and control groups in terms of levels of haemoglobin, platelet, creatinine, aspartate aminotransfrease (AST), albumin and c-reactive protein (CRP) levels (p>0.05). Urea, alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) values were significantly higher in the case group (p<0.05). In the case group, PCR in the spot urine, ACR in the spot urine, protein/day ratio in 24-hour urine, protein/day ratio in 12-hour urine and in secondary 12-hour urine were significantly higher (p<0.001). A positive and strong correlation was detected between PCR and ACR in the spot urine sample, and protein levels of 24-hour, 12-hour and secondary 12-hour urine in the case group of the present study (p<0.05). There was not any correlation was detected between PCR and ACR in the spot urine sample, and protein levels of 24-hour, 12-hour and secondary 12-hour urine in the control group (p<0.05). The area under the curve (AUC) for PCR in the spot urine was 0.787cm2 with a cut-off value of 0.21, sensitivity and specifity values of 80% and 75%, respectively. The AUC for ACR in the spot urine was 0.780 cm2 with a cut-off value of 0.19, sensitivity and specifity values of 83.3% and 60%, respectively. Gestational week at birth was significantly lower in the case group (p<0.05). There was not any difference between the groups for mode of delivery (p>0.05). The incidence of emergency termination of the pregnancy was significantly higher in the case group (p<0.05). The incidence of emergency termination of the pregnancy was significantly higher in the case group (p<0.05). Placental abruption was not detected both in the case and control groups. There was not any difference between the groups for intrauterine growth retardation (IUGR) (p>0.05). Consequently, ACR and PCR in the spot urine were detected significantly higher in the patients with PE. Although sensitivity and specificity is not as higher as daily protein quantity measurement, it may be used to support the diagnosis in suspected and urgent cases. Since it is a feasible method, specificity and sensitivity values for diagnosis may be increased through repeated measurements. Since 12-hour urine collection is associated with higher sensitivity and specificity rather than 24-hour urine collection, this method may be used for suspected cases.