Early prediction of pre-eclampsia by measurement of kallikrein and creatinine on a random urine sample.
OBJECTIVE
To assess the measurement of inactive urinary kallikrein (IUK) to creatinine (Cr) ratio (IUK:Cr) on an untimed urine sample, collected between 16 and 20 weeks of pregnancy, as a predictive test for the development of both proteinuric and nonproteinuric pre-eclampsia.


METHODS
A prospective longitudinal study.


METHODS
A clinic for antenatal care and a university research department.


METHODS
Three hundred and seven normotensive women randomly selected (124 nulliparous and 183 parous) attending the antenatal clinic for their booking visit.


METHODS
1. Nonproteinuric pre-eclampsia: a rise in diastolic blood pressure of 25 mmHg or more and a crossing of the threshold of 90 mmHg; 2. Proteinuric pre-eclampsia: same as 1. plus the development of significant proteinuria ( > 1 + on urine dipstick).


RESULTS
Thirty-seven women developed pre-eclampsia, 12 of whom had proteinuria. Median IUK:Cr ratio in this group was 78.27, compared with 358.19 in the remainder. Analysis of receiver-operator characteristics gave an area under the curve of 0.803. An IUK:Cr ratio of 170 or less in this study predicted nonproteinuric or proteinuric pre-eclampsia with a sensitivity of 70% and a specificity of 86%. Ten of the twelve women who had proteinuria had an IUK:Cr below 170. Median IUK:Cr for those with proteinuric pre-eclampsia was 72.91.


CONCLUSIONS
Measurement of IUK:Cr on a urine sample, collected between 16 and 20 weeks of gestation, represents a simple and practical test for the risk of subsequent pre-eclampsia, with a sensitivity and specificity comparable to those reported by other investigators using the widely recognised, but less practical, angiotensin II sensitivity test.
Millar
J G
JG
Department of Renal and Endocrine Medicine, University of Southampton, Portsmouth, UK.
Campbell
S K
SK
Albano
J D
JD
Higgins
B R
BR
Clark
A D
AD
D000328:Adult; D003401:Creatine / Q000652:urine*; D005260:Female; D006801:Humans; D007610:Kallikreins / Q000652:urine*; D008137:Longitudinal Studies; D011225:Pre-Eclampsia / Q000175:diagnosis / Q000652:urine*; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011296:Prenatal Diagnosis / Q000379:methods; D011446:Prospective Studies; D012680:Sensitivity and Specificity
D007610:Kallikreins; D003401:Creatine