Enterobius vermicularis causing acute appendicitis, a case report with literature review

Enterobius vermicularis Related Acute Appendicitis: A Case Report and Review of the Literature

While the debate on the association between Enterobius vermicularis (E. vermicularis) and acute appendicitis has not been settled, a few case reports of this very rare encounter are beginning to come to light. E. vermicularis is one of the most common parasitic infections around the world, and acute appendicitis, on the other hand, is also a commonly encountered condition in general surgery. However, the association between these two conditions remains controversial. Here we present a case report of a young woman with appendicitis associated with E. vermicularis.

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.

Characterization of antigens of Enterobius vermicularis (pinworm) eggs

Enterobiasis (pinworm infection) caused by Enterobius vermicularis is a common parasitic infection prevalent worldwide especially in children. Infection is diagnosed by microscopic detection of E. vermicularis eggs on perianal swabs. This study aimed to characterize the antigens of E. vermicularis eggs as a preliminary step towards identifying diagnostic targets for detection in infected individuals. The study was conducted between October 2019 and February 2020, following approval from Ethics Review Committee of the Faculty of Medicine, University of Colombo (EC-19-034). E. vermicularis eggs were harvested from perianal swabs using acetone and purified with 1× PBS (pH 7.2). A portion of eggs was used for preparing antigen slides, while the rest were sonicated and vortexed with glass beads and inoculated subcutaneously (with weekly booster doses) into a Wistar rat for developing antibodies. Blood drawing from rat was done weekly for 5 weeks. Confirmation of the presence of antibodies was done by surface immunofluorescence against eggs on the antigen slides. Protein bands were determined using SDS-PAGE assay and immunogenic antigen bands were determined by reacting with antiserum after immunoblotting. The band sizes of the proteins were determined against corresponding bands of a protein ladder. Surface immunofluorescence was positive with serum obtained from day 14 post-inoculation from the Wistar rat as well as that obtained from a person with chronic enterobiasis. The most prominent and immunogenic protein bands identified from egg antigens were 21 kDa, 66 kDa, 83 kDa, 96 kDa, 112 kDa, 121 kDa, 140 kDa and 151 kDa. Methods used in this study were effective in obtaining E. vermicularis egg antigens which were immunogenic. Furthermore, surface antigens of intact eggs reacted with antibodies developed against crushed egg antigens. These findings may pave the way for the development of effective immunodiagnostics.

Comparison of the RIPASA and Labeda Scoring Systems to Assess the Morphological Severity of Acute Appendicitis

BACKGROUND: Acute appendicitis is the most common emergency surgical case, leading to further complications if not treated immediately. Limited diagnostics infrastructure is an obstacle in developing countries, especially in the regions. Therefore, alternatives such as clinical scoring systems are required to assist in diagnosis. AIM: This study aimed to compare the use of the RIPASA and Labeda scores to assess the severity of acute appendicitis morphology by determining the accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and negative appendectomy rate. METHODS: This was a cross-sectional study designed to assess the severity of morphology of intra-operative acute appendicitis in Dr. Chasan Boesoirie Hospital and network hospitals in Ternate, North Maluku, Indonesia. Data regarding patient characteristics, leukocytes, and acute appendicitis severity were collected and analyzed alongside RIPASA and Labeda scores using the Chi-square test. p < 0.05 were considered statistically significant. RESULTS: Of 59 cases, 39 (66.1%) were complicated acute appendicitis and 20 (33.9%) were noncomplicated acute appendicitis. Chi-square test results showed that there was a significant relationship (p ≤ 0.001) between RIPASA/Labeda scores and the severity of acute appendicitis morphology. CONCLUSION: RIPASA and Labeda scores had the same accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for acute appendicitis severity. Thus, RIPASA and Labeda scores can be used by physicians to help establish a diagnosis of acute appendicitis and determine the need for emergency surgery, as well as predict the possibility of morbidity/complications in patients.

Acute appendicitis caused by Enterobius vermicularis: Observations from a case report

Enterobius vermicularis is the most common parasitic worm responsible for gastrointestinal infection worldwide. Acute appendicitis due to E. vermicularis is a rare infection, affecting mostly the children. In this report, we present the case of a 5-year-old girl infant infected by E. vermicularis found in the appendix lumen. A couple of histopathological and parasitological analyses followed by imaging allowed us to diagnose accurately the etiologic agent. Clinicians should be aware of this parasitosis as a possible cause of acute appendicitis.

Prevalence of Enterobius vermicularis infections and associated risk factors among schoolchildren in Nakhon Si Thammarat, Thailand

Background

Enterobius vermicularis infection is an important public health problem worldwide, especially among schoolchildren in tropical and subtropical countries. The prevalence of E. vermicularis infections varies in each region of Thailand; however, its status remains unknown among children who live in rural areas of the southern region. This study aimed to evaluate the current prevalence of E. vermicularis infections and to identify the risk factors for infection among schoolchildren who live in rural communities in Nakhon Si Thammarat, Southern Thailand.

Results

The overall prevalence of E. vermicularis infections was 5.79% (23 of 397). According to a multivariate analysis, the following were found to be risk factors associated with E. vermicularis infections (P < 0.05): those of the male sex (AOR = 4.03, 95% CI 1.22–13.29), those in the 3–6 year age group (AOR = 4.85, 95% CI 1.51–15.59), those who have a mother with a primary school education level (AOR = 11.22, 95% CI 1.75–71.77), those who have older sibling(s) (AOR = 6.25, 95% CI 1.83–21.26), those who have younger sibling(s) (AOR = 6.24, 95% CI 2.00–19.44), those who sometimes wash their hands after using the toilet (AOR = 5.25, 95% CI 1.24–22.21), those who keep their fingernails long (AOR = 29.97, 95% CI 6.16–145.85), and those who suck their fingers (AOR = 3.59, 95% CI 1.21–10.66).

Conclusions

This was the first report that revealed the prevalence of E. vermicularis infections among children who live in rural areas of Southern Thailand through detection using the Scotch tape technique. This study demonstrated that the high prevalence of E. vermicularis infections in schoolchildren with siblings was a significant independent predictor and that the transmission of this infection may occur in the family through their school-age siblings. In addition, children who have poor personal hygiene have a high prevalence of E. vermicularis infections. Therefore, maintaining good handwashing habits, keeping one’s fingernails short, and avoiding sucking one’s fingers should be important preventive measures against infection. Moreover, health literacy or health education, especially for parents or the principal caretakers of children, should be implemented to reduce E. vermicularis infections.