Pre-eclampsia screening/ prediction assays
Every year 2,000 pregnant women in Ireland are affected by PE. In severe forms (10% of cases), maternal, fetal and/or neonatal complications can develop rapidly with serious complications and a potentially fatal prognosis. Induced delivery may be proposed by the clinician based on the clinical signs of the patient and the impact on the fetus.
Assays of pre-eclampsia biomarkers can be used for:
- SCREENING in the 1st trimester of pregnancy:identifying patients at risk of developing pre-eclampsia who could benefit from preventive measures (for example, treatment with 150-160 mg aspirin implemented 16 WA) and/or intensive out-patient monitoring.
- NEW: PREDICTIVE in the 2nd semester of pregnancy:allows prediction or exclusion of pre-eclampsia several weeks in advance of its onset so that early care can be provided to prevent complications or the patient can be reassured and kept at home.
Benefits of screening in the 1st trimester:
- Establish close obstetric monitoring
- Initiate aspirin therapy at low doses before 16 WA
"PE risk" patients can be screened for the presence of risk factors with the Doppler measurement of the pulsatility
index (PI) of the uterine arteries (UAD), mean arterial pressure (MAP) and the assay of PAPP-A and PIGF biomarkers.
Benefits of the predictive test for 2nd trimester (>20WA):
- Reassure and keep at home patients with a very low short-term risk (80% of patients).
- Early warning for patients who are likely to develop the first signs of PE (headache, visual disturbances, edema, abdominal pains ...).
- Referral of patients with a high short-term risk for early hospitalization or regular monitoring.
Ratio used: sFlt-1 / PlGF : The imbalance in sFlt-1 and PlGF concentrations is detectable several weeks before the clinical onset of pre-eclampsia. The sFlt-1/PlGF ratio has a better positive predictive value (PPV) than the measurement of sFlt-1 by itself.