Enterobius vermicularis-associated appendicitis: A 22-year case series and comprehensive review of the literature

Compilation of Evidence Supporting the Role of a T Helper 2 Reaction in the Pathogenesis of Acute Appendicitis

Despite being the most common abdominal surgical emergency, the cause of acute appendicitis (AA) remains unclear, since in recent decades little progress has been made regarding its etiology. Obstruction of the appendicular lumen has been traditionally presented as the initial event of AA; however, this is often the exception rather than the rule, as experimental data suggest that obstruction is not an important causal factor in AA, despite possibly occurring as a consequence of the inflammatory process. Type I hypersensitivity reaction has been extensively studied, involving Th2 lymphocytes, and cytokines such as IL-4, IL-5, IL-9 and IL-13, which have well-defined functions, such as a positive-feedback effect on Th0 for differentiating into Th2 cells, recruitment of eosinophils and the release of eosinophilic proteins and the production of IgE with the activation of mast cells, with the release of proteins from their granules. Cytotoxic activity and tissue damage will be responsible for the clinical manifestation of the allergy. AA histological features are similar to those found in allergic reactions like asthma. The intestine has all the components for an allergic immune response. It has contact with hundreds of antigens daily, most of them harmless, but some can potentially induce an allergic response. In recent years, researchers have been trying to assess if allergy is a component of AA, with their latest advances in the understanding of AA as a Th2 reaction shown by the authors of this article.

Intestinal Parasitic Infections in 2023

Intestinal parasites include intestinal protozoa and intestinal helminths. Intestinal parasitic infections (IPIs) pose a global health problem affecting over one billion people worldwide. Although these infections are predominantly seen in the developing world, they are frequently seen in the developed countries, particularly in immunocompromised patients. Patients' clinical presentations generally include diarrhea, dysentery, abdominal pain, nausea, vomiting, nutritional deficiency, iron deficiency anemia, anal and perianal itching, and rarely intestinal obstruction. The intestinal parasites have similarities in their mode of transmission and life cycle. The stool test is the primary way of diagnosing IPIs. Treatment is given with various anti-parasitic agents. However, appropriate preventive measures are essential for successfully controlling the IPIs.

An Evaluation of the Efficacy of Systemic Immune-Inflammation Index in Predicting Enterobius-Associated Appendicitis Preoperatively

Objective

Our study aimed to retrospectively evaluate Enterobius-associated appendicitis cases and compare them with acute appendicitis cases in terms of parameters such as the neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP)-to-lymphocyte ratio (CLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII). We primarily aimed to evaluate the utility of SII in the differential diagnosis of Enterobius-associated appendicitis.

Methods

The appendectomy specimens of pediatric patients who were operated on for acute appendicitis between June 2016 and August 2022 were retrospectively evaluated. Enterobius-associated appendicitis cases were included for analysis. All patients were evaluated regarding age, gender, blood count, surgery, and pathology reports. Pathology reports were evaluated for the presence of histological signs of acute appendicitis. The patients were classified into an Enterobius-associated appendicitis group and a regular acute appendicitis group. CRP, white blood cell (WBC), red cell distribution width (RDW), neutrophils, lymphocytes, NLR, monocytes, eosinophils, platelet (PLT), PLR, CLR, and SII values were compared between the two groups.

Results

Eleven cases of Enterobius-associated appendicitis were identified out of 430 total cases (2.55%) examined. The mean age of the group with acute appendicitis was 12.83 ±3.16 years, while the mean age of the group with Enterobius-associated appendicitis was 8.55 ±2.54 years. There was no statistically significant difference in terms of CRP, WBC, RDW, lymphocytes, neutrophils, NLR, monocytes, eosinophils, PLT, PLR, and CLR values between the two groups (p>0.05). However, when the SII values of the participants were analyzed, it was observed that the SII values of the participants in the regular appendicitis group were significantly higher than those of the participants in the Enterobius group (p<0.05). Among the 11 Enterobius-associated appendicitis patients, seven appendectomy specimens revealed no inflammation and were regarded as negative appendectomy (63.63%).

Conclusion

This is the first study to demonstrate the utility of preoperative SII evaluation in Enterobius-associated appendicitis. SII is a simple, easy-to-calculate indicator of Enterobius-associated appendicitis and aids in the preoperative differential diagnosis of acute appendicitis.

Fatal Case of a Child Harboring Enterobius vermicularis

Enterobius vermicularis is a threadlike parasite also known as "pinworms". It is the most common helminth infection, affecting the gastrointestinal tracts of children worldwide, although it seldom causes any fatalities. Enterobius vermicularis infections are usually asymptomatic and may only cause anal pruritis, with occasional reported cases of ectopic migration into the appendix or the female genital tract by adult pinworms. Here, we report a case of a 15-year-old girl who presented to the emergency department with high-grade fever, vomiting, and vague abdominal pain for three days. She was diagnosed with acute abdominal pain and underwent emergency ileocecectomy, but died the following day. Pathological examination of ileocecal junction showed intraluminal and intramural Enterobius vermicularis, which were attributed as the cause of her death in the absence of any other pathologies. Death due to Enterobius vermicularis is rare; this case calls for clinicians to be vigilant in exploring Enterobius vermicularis infections in patients with undiagnosed acute abdominal pain, since it could be a potential cause of death.