EP17.54: Assessment of the angiogenic ratio versus glycosylated fibronectin in predicting adverse neonatal outcome in women with suspected pre‐eclampsia

To compare inter-manufacturer angiogenic ratio rule-in/rule-out predictive performance for composite adverse maternal and neonatal outcome versus a point-of-care (PoC) test in East Asian women presenting with a singleton pregnancy after 20 weeks of gestation with hypertension ± clinical features of pre-eclampsia (PE). Pro- and anti-angiogenic levels of placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt1) were measured using the Roche Cobas e411, BRAHMS Kryptor, Ningbo-Aucheer Imagin1800 immunoassays in 225 maternal serum samples, 67 of whom subsequently developed PE. Glycosylated fibronectin (GlyFn) levels were determined using the LumellaTM PE PoC test. Women with PE at presentation were excluded. PE was diagnosed according to the ISSHP 2021 classification. The sFlt1:PlGF ratio was stratified as “High” or “Low” using assay specific thresholds equivalent to a Roche sFlt1:PlGF ratio of 38. GlyFn was classified as “High” or “Low” using a GlyFn level of 263 ug/ml. Adverse outcome was defined as prematurity, small for gestational age, neonatal death, neonatal ICU admission, 5th min Apgar <7, perinatal depression and neonatal sepsis/RDS/IVF/NEC. Negative predictive value (NPV) to rule-out composite adverse outcome and positive predictive value (PPV) to rule-in composite adverse outcome at time of presentation were determined. 159 pregnancies had an adverse outcome. NPV of “Low” Roche, Kryptor, and Ningbo-Aucheer sFlt-1:PlGF ratio and “Low” GlyFn to rule-out adverse outcomes were respectively 36.6%, 35.8%, 38.6%, 29.6%. Corresponding manufacturers PPV of a “High” sFlt-1:PlGF ratio or GlyFn to rule-in adverse outcomes were 83.1%, 83.8%, 83.9%, 71.4%. NPV and PPV of different assay manufacturers sFlt-1:PlGF ratio were similar once standardised to a common equivalent threshold and higher than GlyFn.