Article Text
Abstract
Objective To review the use of spot protein creatinine ratio as a diagnostic test for preeclampsia in comparison to 24 hour urine.
Methods This was a retrospective observational study on 100 pregnant women referred to the day assessment unit with new onset hypertension. A spot test for PCR and a 24 hour collection were commenced at the same time. Patients with renal disease, proven UTI and diabetes were excluded. Data was analysed using Microsoft Excel. Significant proteinuria was defined as a PCR value of 30 mg/mmol and 300 gms/24 hours or more with 24 hour urine. With 24 hour urine as a standard, having excluded the under and over collections, the co-relation between PCR and 24 hour urine protein was determined by Spearman co-relation coefficients. The sensitivity, specificity, NPV and PPV were calculated.
Results Of the 100 women, 7 were excluded due to proven UTI 43 patients were subsequently excluded as the 24 hour urine collections were incomplete as deemed by the urinary creatinine excretion. Among the rest of the 50 patients, The PCR values were found to correlate well with the 24 hour collection results. The test is found to have a sensitivity of 90% and a specificity of 84% with a positive likelihood ratio (LR) of 5.2 and a negative LR of 0.1.
Conclusion The 24 hr collection is cumbersome, time consuming and there can be errors in collection, while the spot PCR test compares very well to the 24 hour protein test, is easier to perform.