Neutrophil-to-Lymphocyte Ratio, Platelet-to-Lymphocyte Ratio and Complete Blood Count Components in the First Trimester Do Not Predict HELLP Syndrome

Background and Objectives: Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), mean platelet volume (MPV), and other components of the routine complete blood count (CBC) were found to be sensitive biomarkers of preeclampsia and other inflammatory obstetric conditions in previous studies, with conflicting results. We speculated that the same associations existed with hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome in the first trimester of pregnancy. Materials and Methods: We conducted a retrospective case-control study at a tertiary care hospital in NY (USA), in the time frame between January 2016 and December 2018. Our population consisted of pregnant women in the first trimester: We compared patients with HELLP syndrome (cases) with healthy patients (controls) matched by age, body mass index (BMI), parity, and race. Patients with preeclampsia, infection, and fever were excluded. Venous blood samples were obtained as part of the routine work-up during the first prenatal visit in the first trimester, which includes a CBC. The main outcomes were NLR and PLR, and the secondary outcomes were hemoglobin, RDW, platelet count, MPV, neutrophils, and lymphocytes. Results: There were 10 patients in each group. There were no differences in NLR and PLR levels and other CBC components between the two groups. Conclusions: In our study NLR, PLR, and other CBC components did not predict HELLP syndrome. We speculate that HELLP syndrome has a sudden increase of tissue inflammation in the third trimester that is not manifested during the early phases of placentation. Larger studies are needed to evaluate the true ability of NLR, PLR, and CBC components to predict HELLP syndrome in the first trimester.