D-Dimer: An Early Marker of Disseminated Intravascular Coagulation in Preeclampsia and Eclampsia

Introduction Preeclampsia, a disease of unknown etiology, affects multiple organ systems and carries a grave prognosis for both the mother and fetus. Any hypertension and proteinuria developing after 20 weeks of gestation in a previously normal patient warrants investigation for this disease. Coagulation studies may be deranged in preeclampsia and eclampsia due to their association with disseminated intravascular coagulation (DIC). In DIC, the underlying basic pathology is endothelial dysfunction and intense vasospasm; it can affect any organ but most commonly affects the brain, kidneys, uterus, and placenta. Materials and method This retrospective cross‑sectional study was conducted on a sample size of 432 subjects over a two-year period in a tertiary referral center. Two categories of patients were identified and selected: preeclampsia patients and the control group, which comprised other admitted pregnant patients age-matched with the study group. Patient data were entered into Excel and analyzed using SPSS Statistics Version 24. Continuous variables were represented as mean and standard deviation (SD), while categorical variables were represented as frequency and percentage. Statistical analysis was performed using a parametric test of ANOVA. Significance level (p-value) was 0.05. Results Among the patients, 180 (41.7%) patients were nullipara, while 252 (58.3%) were multipara. All patients showed hypertension, with 382 (88.4%) patients having blood pressure values between 140/90 and 160/110 mmHg and 50 (11.2%) having values above 160/110 mmHg. Among the patients, 191 (44.2%) had grade 2 proteinuria, 79 (18.2%) had grade 3 proteinuria, and 18 (4.2%) had grade 4 proteinuria, as determined by the dipstick method. Additionally, 148 (34%) subjects had platelet count < 150,000/mm³; 31 (7.1%) subjects had severe thrombocytopenia; and 73 (16.8%) subjects had D-dimer < 0.5 µg/mL, 247 (63.4 %) between 0.5 and 4 µg/mL, and 85 (19.6%) ≥4 µg/mL. The observed decrease in platelet count and fibrinogen levels with progressively increasing D-dimer is clinically relevant and in alignment with the pathophysiology of consumptive coagulopathy. The observed trend in our study is in line with the expected behavior of coagulation markers during ongoing increasing fibrinolytic activity. Severe disease presentation is associated with higher proteinuria levels, overt thrombocytopenia, higher fibrinogen levels (unless a patient has landed into consumptive coagulopathy case, which shows decreased fibrinogen levels), and highly elevated D-Dimer levels. Conclusion Preeclampsia increases D-dimer concentrations beyond 0.50 mg/L, which is considered the normal threshold for D-dimer levels, resulting in a false-positive D-dimer test. The D-dimer test performed as an initial diagnostic measure can preclude the need for imaging and, along with other laboratory tests and clinical signs and symptoms, may aid in diagnosis even in non-classical cases, thus reducing fetal mortality.