DIAGNOSTIC ACCURACY OF ANGIOGENIC MARKERS IN PREECLAMPSIA DIAGNOSIS – A REALITY IN A TERTIARY CENTRE

Problem Statement

sFlt-1/PlGF ratio has been suggested as a potential biomarker for preeclampsia diagnosis, but its diagnostic accuracy is still unclear.

Methods

This is a retrospective case-control study of pregnant women admitted to our materno-fetal unit due to suspected preeclampsia between January 2021 and December 2022. Group A consisted of women with gestational hypertension (n=43) and Group B of women with confirmed preeclampsia (n=99). sFlt-1/PlGF ratio was collected at admission in both groups. Low angiogenic imbalance was defined as lower than 38. Severe imbalance was defined as above 85 and 110, for gestational ages under and at or above 34 weeks, respectively.

Results

Mean gestational age at admission was similar between groups (p=0.142). In group A, low, moderate and high sFlt-1/PlGF ratios occurred in 60.5%, 32.6% and 7.0% of the cases, respectively. On the other hand, in group B, low, mild and severe angiogenic imbalance was present in 30%, 26% and 44% of the cases. Significant differences were found between groups (p<0.001). No correlation was found between ratio values and gestational age (p=0.76). Mean value for sFlt-1/PlGF ratio was 33.7 ± 35.6 in group A and 179.0 ± 277.4 in group B (p<0.001).

When considering ratios above 38 as threshold for a positive test, the test’s sensitivity was 73.7% and specificity was 51.2%. Positive (PPV) and negative predictive values (NPV) were 77.7% and 45.8%, respectively. Differently, when considering a positive test as severe angiogenic imbalance, at thresholds of 85 ad 110 according to gestational age, sensitivity decreased (44%), but specificity increased significantly (93%), at a PPV of 93.6% and NPV of 41.7%.

Conclusion

Severe angiogenic imbalance is characteristic of preeclampsia, regardless of gestational age at its measurement. Nevertheless, its reduced sensitivity at higher thresholds might increase failure of diagnosis and morbidity.