40 Analysis of the neutrophil-lymphocyte ratio as a marker of severity in pregnant women with acute appendicitis

Abstract Introduction The neutrophil-to-lymphocyte ratio (NLR) has emerged in recent years as a predictor of inflammation in various infectious pathologies. Among them, its value in predicting severity or complications in acute appendicitis has been studied and validated in adults and children. Although these studies are clear about its usefulness, it’s still unclear what value is optimal as a cut-off point. However, there is a knowledge gap in whether this evidence can be extrapolated to pregnant women with acute appendicitis. Gestation is a physiological situation that causes an intrinsic alteration of the immune system, altering white blood cell counts, and making the pregnant woman vulnerable to infection. Among these, acute appendicitis is the most frequent cause of acute abdomen in pregnancy. The aim of this study is to analyse whether NLR can play a predictive role in the severity of acute appendicitis in pregnant women. Methods We reviewed medical records for all consecutive pregnant patients admitted for acute appendicitis from 2018 to 2023 in our tertiary care university hospital. Results Fourteen patients were analysed, mean age was 29 years. Five (35.7%) were in the first trimester, 4 in the second trimester and 5 in the third trimester. The mean evolution time from the onset of symptoms to diagnosis was 2.4 days. The most used diagnostic technique was abdominal ultrasound (13 cases) and only in one patient MRI was performed for diagnosis. Four appendectomies had an open approach, and the others were laparoscopic. During surgery, peritonitis was observed in 9 cases (64%), and in 4 of them there was generalized peritonitis. In 2 cases acute appendicitis triggered birth, both in the third trimester, and both presented peritonitis. The mean hospital stay was 4 days, and 11 patients (78.5%) received empirical antibiotic therapy after surgery. Of the 14 cases, 6 presented complicated acute appendicitis in the pathological study, which did not correlate with intraoperative findings. CPR was significantly elevated in cases with peritonitis (mean 163 mg/l in cases with peritonitis versus 52 mg/l in non-peritonitis). We found the same correlation between NLR and peritonitis, significantly higher with a mean of 15.84% in the peritonitis group versus 7.31% in cases without peritonitis, However, we did not find a correlation between the anatomopathological diagnosis and the NLR. Conclusions In 5 years, only 14 pregnant women presented acute appendicitis in our tertiary hospital, despite being the most common cause of acute abdomen during pregnancy. Due to the small sample we cannot draw conclusions, but we can observe trends. It seems that the NLR behaves similarly as a predictor of complication or severity, especially if there is peritonitis. In published literature, it seems that the average NLR in pregnant women is higher than that of the non-pregnant population. We also observed that more than half of appendicitis in pregnant women presented peritonitis, whether localized or generalized, which is higher than in the general population. It seems that the NLR may behave similarly in pregnant women with peritonitis as in the non-pregnant population, so it could help predict the presence of peritonitis to provide early care in this vulnerable population.