Pediatric Acute Abdominal Pain

Interesting Cases in PR

|

April 21, 2023

In this case, a 10-year-old boy visited the emergency room due to acute abdominal pain. According to the patient’s parents, the stomachache had been progressing over the course of 22 days and had been irradiating into the right iliac fossa (RIF). This affliction had been accompanied by nausea, mild hematuria, and mild leukocytosis. An abdominal ultrasound was performed, although the ileocecal appendix could not be identified. Thus, the patient was discharged with a suspected urinary infection and treated with antibiotics. Nevertheless, the recurrence of the symptoms brought the patient back to the hospital with acute abdominal pain in the RIF and a positive Rovsing sign. At this time, blood work showed no evidence of leukocytosis although eosinophilia was present. Due to this scenario, an ultrasound, and an abdominal CT scan were ordered, yielding a retrocecal appendix whose diameter was larger than its supposed size.

As a result, the patient underwent a laparoscopic appendectomy. After the intervention, the patient's symptoms disappeared and antibiotics treatment remained in place.

‍

What is the most likely diagnosis?

a. Appendicitis with Enterobius vermicularis

b. Appendicitis with Ascaris lumbricoides

c. Appendicitis with Giardia lamblia

d. Appendicitis with Entamoeba histolytica

‍

Figure 1.

‍

Figure 2.

‍

Figure 3.

‍

Know the correct answer?

Read full article

Click here to open the document

Click here to see the answer

Answer: A

Pathological analysis of the appendix showed a congested wall, opaque serosal covering with serofibrinous exudate, eosinophilic infiltrate, lymphoid hyperplasia, mucosal ulceration, suppuration, and vascular congestion; all consistent with Enterobious Vermicularis appendicitis.

Acute appendicitis is one of the most common causes of acute abdomen, being the most frequent surgical emergency. Obstruction of the vermiform appendix has been proposed as the main etiology of this inflammatory condition, which is why some authors consider that the obstruction is the result and not the cause of inflammation of the appendix. Currently, there is no single theory that explains all cases of acute appendicitis, which is variable depending on the age range.

Parasitic infections of the appendix are a rare etiology of acute appendicitis, although they should always be considered in children with abdominal pain. Among these parasitoses, microbiological agents such as Enterobius, Ascaris, Giardia, and E. histolytica should be considered.

Enterobiasis is a family-type infection produced by Enterobius vermicularis, formerly known as Oxiurus vermicularis, is characterized by pruritus (anal, nasal, vulvar, etc.), and gastrointestinal and nervous disorders. This parasite is a small, filiform, white obligate nematode that affects millions of people. This is the most frequent infection by nematodes worldwide, although there is a marked geographic and population variability; yet, the highest prevalence of this parasitosis occurs in children and adolescents.

It is an exclusive human parasite that is transmitted through the fecal-oral route. The most common site of colonization is the anal margin, which is why anal itching is the most common symptom. The parasite can move to other ectopic regions, giving rise to symptoms due to local inflammation or even bacterial superinfection. Among them, it is worth highlighting the infiltration of the fallopian tube, which can cause tubo-ovarian abscesses, and granulomas in the vulva, vagina, uterus, or ovaries. There is also an increase in the incidence of urinary tract infections, due to migration through the urethra and bladder.

Within their intestinal habitat, these parasites can migrate and reach the cecal appendix where many investigators consider that they play a key pathophysiological role in the fostering of acute appendicitis.

On the other hand, Enterobius vermicularis can irritate the appendicular mucosa, producing microtraumas in this tissue and thus allowing germs to enter the wall, vital for the inflammatory process typical of appendicitis.

During microscopical evaluation using hematoxylin-eosin stain, the presence of eggs that are classically white, and transparent is evident alongside its acute inflammatory infiltrate in the appendicular wall.

In conclusion, we must not forget that parasitosis associated with appendicitis is a rare pathology, although we must maintain high suspicion in pediatric patients with symptoms of nonspecific abdominal pain or anal pruritus. In the case of acute appendicitis secondary to infection by E. vermicularis, appendectomy is not the definitive treatment, being necessary to complete it with anthelmintic drugs (albendazole or mebendazole) in order to prevent progression or treat the larval parasitic infection.

‍

References

1. Efared, B., Atsame-Ebang, G., Soumana, B.M. etal. Acute suppurative appendicitis associated with Enterobiusvermicularis: an incidental finding or a causative agent? A casereport. BMC Res Notes 10, 494 (2017).

2. H. Alemayehu, C.L. Snyder, S.D. St Peter, D.J.Ostlie. Incidence and outcomes of unexpected pathology findings afterappendectomy. J Pediatr Surg, 49 (2014), pp. 1390-1392.

3. L.W. Lamps. Beyond acute inflammation: a review ofappendicitis and infections of the appendix. Diagn Histopathol, 14 (2008),pp. 68-77.

4. Mohamed A, Bhat N. Acute appendicitis dilemma ofdiagnosis and management. Internet J Surg. 2010;23(2):1528–8242.

5. Zuhair D. Hammood, Abdulwahid M. Salih, Shvan H.Mohammed, Fahmi H. Kakamad, Karzan M. salih, Diyar A. Omar, Marwan N. Hassan,Shadi H. Sidiq, Mohammed Q. Mustafa, Imad J. Habibullah, Drood C. Usf, Anmar E.Al obaidi. Enterobius vermicularis causing acute appendicitis, a case reportwith literature review, International Journal of Surgery Case Reports (2019),Vol 63, pp. 153-156.

‍

Contributors

José Lev Alvarez Gomez, BS, MA, MA (Content), Gloria Ramos Rivera, MD & Juan C. Santa-Rosario, MD (Images).