Investigation of the effectiveness of transcutaneous bilirubin measurement in the diagnosis of preeclampsia

Preeclampsia is one of the most complex complications in obstetrics, affecting 2%–8% of pregnancies worldwide. Alongside factors such as postpartum hemorrhage, sepsis, and maternal infection, it remains one of the leading causes of maternal morbidity and mortality. Preeclampsia is currently responsible for over 17% of maternal deaths and is the third most common cause of maternal mortality globally. It is a multisystemic disease presenting with various clinical profiles and can occur even in the absence of hypertension or proteinuria. The onset and clinical progression of the disease are unpredictable, necessitating robust tools for its diagnosis, treatment, and prediction. In our study, we aimed to evaluate the effectiveness of bilirubin measurements obtained using a non-invasive transcutaneous bilirubin (TCB) device from different body regions in pregnant women diagnosed with preeclampsia. The study included 86 pregnant women who were admitted to and delivered at the Department of Obstetrics and Gynecology, Elazig Fırat University Faculty of Medicine, between October 2023 and September 2024. Participants were divided into three groups: healthy pregnancies (Group 1, n = 30), pregnancies with preeclampsia (Group 2, n = 30), and severe preeclampsia cases (Group 3, n = 26). In addition to routine antenatal blood tests, transcutaneous bilirubin measurements were performed on all participants from two different regions (maternal forehead skin and the skin area corresponding to the uterine fundus) using a TCB device. The average of these two measurements was also recorded. Each region was measured three times, and the mean of the three measurements was used. Statistical analyses included ANOVA (Tukey test) for normally distributed quantitative independent data, While Kruskal-Wallis and Mann-Whitney U tests were used for non-normally distributed data. For qualitative independent data, the chi-square test was used, and Fisher's exact test was applied when chi-square test conditions were not met. Pairwise group comparisons were performed using the Mann-Whitney U (MWU) test, with a p-value of <0.05 considered statistically significant. No statistically significant differences were observed in age, gravidity, parity, abortion, curettage number, or body mass index parameters among the patients in Groups 1, 2, and 3. Total serum bilirubin levels were 0.47 ± 0.17, 0.50 ± 0.46, and 0.62 ± 0.48 in Groups 1, 2, and 3, respectively, showing no significant difference (p > 0.05). However, transcutaneous bilirubin levels in the severe preeclampsia group (Group 3) were significantly higher compared to Groups 1 and 2. The forehead, fundus skin, and average TCB values in Group 3 were 7.12 ± 1.81, 6.12 ± 2.25, and 6.63 ± 1.69, respectively (p < 0.05). In Group 1, these values were 3.07 ± 0.85, 2.35 ± 0.97, and 2.71 ± 0.76, while in Group 2, they were 6.09 ± 1.94, 4.94 ± 1.64, and 5.52 ± 1.59, respectively. Comparisons between Groups 1 and 2 revealed statistically significant higher TCB values in Group 2 (p < 0.05). Similarly, comparisons between Groups 2 and 3 showed statistically significantly higher TCB values in Group 3 (p < 0.05).