sFlt-1, PlGF, sFlt-1/PlGF ratio and uterine artery Doppler for preeclampsia diagnostics

Background and objective: Angiogenic factors such as soluble fms-like tyrosine kinase 1 (sFlt- 1) and placental growth factor (PlGF) play a key role in the pathogenesis of preeclampsia. Uterine artery (UA) blood flow is important for preeclamptic pregnancy outcome, but small amount of evidence suggests UA dopplerometry for preeclampsia diagnostics and management. The aim of our study was to compare the value of angiogenic factors and UA dopplerometry in preeclampsia diagnosis and determine cut-off values to obtain the highest sensitivity and specificity of the parameter.
Materials and methods: We performed a case controlled study of 72 pregnant women with preeclampsia and 72 healthy matched controls. SFlt-1 and PlGF were measured in serum samples, the sFlt-1/PlGF ratio was calculated and UA pulsatility (PI) and resistance (RI) indexes were registered.
Results: Significantly higher levels of sFlt-1, sFlt-1/PlGF ratio and mean UAPI and UARI and lower levels of PlGF were found in preeclampsia group when compared to controls. The highest sensitivity and specificity for preeclampsia had SFlt-1/PlGF and PlGF with the cut-off values of ≥35 (sensitivity of 95.8% and specificity of 96.2%, respectively) and ≤138.6 pg/mL (sensitivity of 95.8% and specificity of 93.7%, respectively). For diagnostics of early-onset preeclampsia, all factors sFlt-1, PlGF and sFlt-1/PlGF had equal significance with the cut-off values of ≥7572 pg/mL (specificity of 97.5%, sensitivity 92.3%), ≤100.5 pg/mL (specificity 96.2%, sensitivity of 100%) and ≥54.6 (specificity 97.5%, sensitivity 97.5%) respectively.
Conclusions: The sFlt-1/PlGF ratio and PlGF are superior to sFlt-1, UAPI and UARI for preeclampsia diagnosis. For early-onset preeclampsia diagnostics either sFlt-1 or PlGF is sufficient.