Molecular and phylogenetic analysis of E. vermicularis in appendectomy specimens from Iran.

Human infection with Enterobius vermicularis occurs worldwide, particularly in children. The role of E. vermicularis in appendicitis is neglected. This study was designed to investigate genotypes of E. vermicularis detected from appendectomy specimens in the human population from Iran and clarify the intra-species variation of the parasite. Seventy appendectomies for acute clinical appendicitis isolates from Azerbaijan and North Khorasan of Iran were used in the present study. The genetic information of Tehran and Hamedan regions was also obtained from GenBank for comparison and analysis. The nucleotide sequence of cytochrome c oxidase subunit 1 (cox1) gene was analyzed to perform genetic differentiation, haplotype network analysis, and population structure. Phylogenetic analysis of all the isolates were included in type B haplogroup. The number of haplotypes in all geographical locations of Iran is not much. Network analysis of sequences for regions such as Thailand, Iran, Denmark, and Poland show three classified subtypes B1, B2, and B3 in the B haplogroup. It seems that the haplotypes of E. vermicularis detected from appendectomy are B type, and divided into three subtypes. Further research using another genetic marker is required to elucidate the genetic variation of the parasites in detail.

A "fruitful" cause of acute appendicitis.

INTRODUCTION: Acute appendicitis is a common health problem mainly due to a lumen obstruction. The obstruction is mainly due to fecal material, lymphoid hyperplasia or parasites. Foreign bodies and especially seeds have been rarely reported as causes of acute appendicitis and account for less than 1% of the different causes. CASE REPORT: The authors described a rare case of acute appendicitis caused by seed and causing diagnostic challenge with the most frequent parasites observed in the appendix lumen. Different arguments were gathered to rule out enterobius vermicularis, taenia species, ascaris infection or schistosomiasis. CONCLUSION: Seed-caused-appendicitis has to be known and identified by pathologists in order to avoid the diagnosis of parasites infection which may induce an overuse of antibiotics after the appendectomy.

Large-bowel obstruction secondary to Enterobius vermicularis pseudotumour.

Enterobius vermicularis infection is typically observed in paediatric patients and manifests with perianal pruritus, but other manifestations or ectopic presentations have been reported in the literature. We present the case of a man in his 60ss with a large-bowel obstruction with symptoms including a 4-day history of progressive abdominal pain, distension, vomiting and absolute constipation. On examination, his abdomen was distended with tinkling bowel sounds on auscultation. Cross-sectional imaging demonstrated an obstructing mass in the distal descending colon. An emergency laparoscopic Hartmann's procedure was performed and the patient made an uneventful recovery. An intraoperative colonoscopy demonstrated numerous white threadworms in the colon. Histological analysis demonstrated a pseudotumour related to Enterobius vermicularis infection. This case represents a rare differential diagnosis for a large-bowel obstruction.

Parasitic Appendicitis in 14.797 Cases: A Retrospective Cohort Study

Objective: This study aimed to determine the frequency of Enterobius vermicularis in appendectomy specimens and evaluate the histopathological characteristics of adult and pediatric cases with E. vermicularis infection. Methods: Appendectomies examined from 1 January 2010, to 1 December 2020, were analysed retrospectively. Cases were divided into two groups: under 18 years (children) and 18 and over (adults). Demographic and histopathological characteristics of patients were also examined. Results: Out of 14.797 patients that underwent appendectomy, 6.130 were children and 8.667 were adults. E. vermicularis was detected in 268 patients, wherein 64.2% were children and 35.8% were adults. In the detection of E. vermicularis in appendectomy specimens, the frequency was higher in children compared to that in adults (2.85%, 1.1%, respectively) (p<0.001). Histopathologically, acute appendicitis was defined in 31.7% (n=85) of 268 cases, and E. vermicularis was found to cause a higher rate of acute appendicitis in adults (p<0.001). Conclusion: The frequency of E. vermicularis in appendectomy specimens is higher in children. However, E. vermicularis causes acute appendicitis more frequently in adults.

Enterobius vermicularis Infestation Mimicking Rectal Malignancy

Enterobius vermicularis is a common intestinal nematode of humans that can be considered relatively harmless. A polypoid lesion mimicking malignancy was detected in the rectum of a 66-year-old female patient who had been operated for sigmoid colon adenocarcinoma in the past. Histopathological examination of the lesion revealed no malignancy but there was adult E. vermicularis nematodes and eggs. In this case report, we aimed to present an enterobiasis infestation that produces non-necrotizing granuloma tissue in the rectum.

Findings in Appendectomies with Enterobius vermicularis Infection: Pinworm Is Not A Cause of Appendicitis

Objective: To evaluate the histopathological findings in appendectomy materials with E. vermicularis infection. Methods: Appendectomy materials with E. vermicularis infection of 24 cases were evaluated for the presence of acute inflammation, congestion, hemorrhage, perforation, lymphoid hyperplasia (LH), necrosis, granuloma, fecalith, obliteration, hyalinization, eosinophilic infiltration and mucosal architectural distortion. Results: The frequency of E. vermicularis among 3222 appendectomies that were scanned for the study was 0.74% (24/3222). Female: male ratio was 1:1 and the median age was 12±9.34 years. The most common findings were LH (100%), and congestion (91.7%) Acute inflammation was found in one third (n=8), with phlegmonous inflammation and/or periappendicitis in 4 of them. The patients with periappendicitis were significantly younger (mean age 4 vs. 14.2 years, p=0.008). Feces was present in the lumen in 79.1% of the patients (fecalith in 25%, soft feces in 29.1% and feces mixed with blood and/or suppuration in 25%). In 6 cases (25%), only E. vermicularis was observed in the lumen, with acute appendicitis in 2 of them. Appendiceal lumen was completely obstructed in 12.5% (n=3), while it seemed narrow due to extensive LH in 3 (12.5%) cases. Fibrous obliteration was seen in 4 patients and it was correlated with age and eosinophil count in lamina propria p<0.05. Conclusion: While E. vermicularis infection appears to be an incidental finding in appendectomies rather than being a cause of appendicitis, it probably stimulates LH which may mimic acute appendicitis clinically.

Enterobius vermicularis Appendiceal Colic.

Enterobius vermicularis associated appendiceal colic and acute appendicitis are rarely encountered in the United States. The 9-year-old patient described in this case presented with right lower quadrant abdominal pain, nausea, and vomiting consistent with acute appendicitis and was brought to the operating room for an appendectomy. Intraoperatively a pinworm, E. vermicularis, was visualized and the presumptive diagnosis of acute appendicitis was revised to E. vermicularis associated appendiceal colic. Retrospective review of the preoperative imaging demonstrates the first reported ultrasonographic image of pinworm inhabitance within the appendiceal lumen. The patient was treated postoperatively with a course of albendazole and recovered appropriately. This article reviews the geographic epidemiology, pathophysiology, surgical, and medical treatment recommendations in the management of E. vermicularis diseases of the appendix. Through dissemination of this ultrasonographic imaging, the authors hope to inform other providers about E. vermicularis associated appendiceal colic and reduce the incidence of avoidable surgeries.

Does the Intestinal Parasite Enterobius vermicularis Cause Acute Appendicitis?

OBJECTIVE: Although intestinal parasitic infections rarely cause acute appendicitis, they are common public health problems in undeveloped and developing countries. Parasitic infections should be kept in mind in patients clinically suspected of having acute appendicitis, and treatment procedures should be adopted according to the etiology. METHODS: Herein we presented the cases of four patients with clinical findings of acute appendicitis. Patients were clinically suspected of having acute appendicitis, and Enterobius vermicularis was detected in the pathological examinations of specimens. Pinworm infections are common parasitic infections that may mimic appendicitis. RESULTS: The pathology of the four cases was noted when the file of 186 patients aged between 4 and 72 years who underwent surgery for acute appendicitis in my hospital was retrospectively reviewed. When the appendectomy specimen was examined histopathologically it was understood that acute appendicitis was caused by Enterobius vermicularis parasite. CONCLUSION: In Enterobius infections, performing systemic therapy for patients and their family members is sufficient. To prevent unnecessary appendectomy, this type of infection should be made to ask in the history and clinical findings of patients.

Enterobius vermicularis in tubo-ovarian abscess: A rare and interesting incidental finding - A case Report.

Enterobius vermicularis is a common intestinal nematode; however, rare extraintestinal Enterobius infections have been reported from different parts of the world. Here, we present a case of tubo-ovarian abscess in an otherwise healthy young sexually active female with no known comorbids with history of on and off lower abdominal pain for one year and high grade fever for one month. On the basis of further workup and radiological evaluation, a preoperative diagnosis of right sided tubo-ovarian abscess was made and salpingo-oophorectomy was performed laproscopically in July 2015. Histopathology of the resected tissue revealed necrosis and in one area Enterobius vermicularis was identified surrounded by neutrophils and eosinophil rich abscess. A final diagnosis of severe acute and chronic salpingo-oophoritis with abscess formation, secondary to Enterobius vermicularis was made. Signs and symptoms of parasitic involvement in tubo-ovarian abscesses are not much different than usual presentations of pelvic inflammatory diseases and identification of a parasite in a tubo-ovarian tissue sample is a rare clinical finding. A high index of suspicion on the part of histopathologist as well as clinician is important for timely diagnosis and effective management of such cases.

Parasitic infestation in appendicitis. A retrospective analysis of 660 patients and brief literature review.

OBJECTIVES: To investigate the incidence of parasitic infestations and inflammation accompanying parasitosis in a series of appendectomy cases.  Methods: Six-hundred-sixty  patients who had undergone appendectomy in Bingöl State Hospital, Bingol, Turkey with the preliminary diagnosis of appendicitis between January 2012 and February 2015 were included in this retrospective study. They were retrospectively evaluated in terms of age, gender and pathological findings. Cases diagnosed with parasitic infestations were re-evaluated histopathologically for inflammatory response.  Results: The mean age was 19.6 years, and the male/female ratio was 1.8. When evaluated in terms of histopathological diagnoses, 573 (86.8%) were diagnosed as acute appendicitis, and parasitic infestation was identified in 12 (1.8%). Among cases with parasitic infestation, Enterobius vermicularis was identified in 9 (75%) and Taenia in 3 (25%) cases. Of cases with Enterobius vermicularis, 4 (44.4%) had lymphoid hyperplasia, 1 (11.1%) had normal-structured appendix vermiformis, and 4 (44.4%) had findings of acute appendicitis. All cases with taeniasis had an inflammatory response: acute appendicitis was identified in 2 (66%) and acute gangrenous appendicitis in 1 (33%) of them.  Conclusion: Parasitic infestations are among the probable causes in appendicitis etiology and should be kept in mind during differential diagnosis. However, whether every parasitic infestation leads to appendiceal inflammatory response is controversial.

Unusual case of appendicitis.

A teenage girl was admitted to the paediatric assessment unit with non-specific abdominal pain that gradually localised to the right iliac fossa (RIF). She remained systemically well; investigations including blood tests, urine sample and abdominal ultrasound were inconclusive. Surgical opinion was sought and the decision was made to perform a diagnostic laparoscopy due to the ongoing pain. Laparoscopy showed no evidence of any significant pathology, and appendicectomy was performed following the routine practice. Numerous pinworms came out while the appendix was resected. The RIF pain resolved and the patient made a full post-operative recovery. A stat dose of mebendazole and amoxicillin were given and the immediate family was also treated. Enterobius vermicularis (pinworm) causes significant morbidity worldwide and has a high prevalence among children in the UK. It can be easily treated and prompt recognition based on clinical symptoms can potentially prevent unnecessary surgery.

[Perforation of the appendix and observation of Enterobius vermicularis]. / Perforeret appendicitis med fund af Enterobius vermicularis.

A nine-year-old girl was admitted to the paediatric ward due to fever and lower abdomen pain through a day. Acute laparoscopic exploration showed a large necrotic perforation at the distal end of the appendix. During the appendectomy multiple small, live Enterobius vermicularis (pinworms) were observed. The patient was admitted for three days of observation and received relevant treatment with intravenous antibiotics and antihelminthic treatment. The histology showed numerous pinworms in the lumen of the appendix and invasion of the pinworms of the submucosal layer and the wall of the appendix.

Enterobius vermicularis salpingitis seen in the setting of ectopic pregnancy in a Malaysian patient.

We report a rare and unusual case of invasive Enterobius vermicularis infection in a fallopian tube. The patient was a 23-year-old Malaysian woman who presented with suprapubic pain and vaginal bleeding. A clinical diagnosis of ruptured right ovarian ectopic pregnancy was made. She underwent a laparotomy with a right salpingo-oophorectomy. Histopathological examination of the right fallopian tube showed eggs and adult remnants of E. vermicularis, and the results were confirmed using PCR and DNA sequencing.

Parasitic infections of the appendix as a cause of appendectomy in adult patients.

OBJECTIVE: Assessment of frequency and clinical findings of parasitic infections for etiology of acute appendicitis. METHODS: Data of 1452 patients who were carried out appendectomy between January 1999 and December 2012 were analyzed retrospectively. Appendectomy was performed in 1159 of the patients with a pre diagnosis of acute appendicitis. Demographics, physical findings, radiologic and laboratory studies, operative findings, pathological results, presence and type of parasitosis were investigated. RESULTS: Among the 1159 patients done appendectomy with a pre diagnosis of acute appendicitis, 719 (62%) were males and 440 (38%) were females. Parasitic infection was demonstrated in 17 (1.4%) of them. Mean average age of these patients was 36.6 ± 20.1 years. Enterobius vermicularis was present in 15 (88.2%) and Entamoeba histolytica in 2 (11.8%) of the patients. Of the pathology specimens of appendix consisting Enterobius vermicularis, 12 (80%) were normal appendix tissues, 1 (6.6%) was acute uncomplicated appendicitis and 2 (13.3%) were perforated appendicitis. One (50%) of the two specimens consisting Entamoeba histolytica was normal appendix and the other (50%) was acute appendicitis. CONCLUSION: Differential diagnosis of parasitic infections in etiology of acute appendicitis should be made properly. It must be remembered that this attention can save patients from a negative laparotomy and morbidity and mortality of it.

[Acute appendicitis and coinfection with enterobiasis and taeniasis: a case report]. / Akut apandisit ve enterobiyaz ile taeniyaz: bir olgu sunumu.

Parasites are rarely associated with inflammation of the appendix. Generally, parasites cause acute abdominal pain via blocking the gut lumen. In this article, we presented a case of appendicitis where Enterobius vermicularis was detected in the surgical specimen and Taenia was detected in the stool. A 31 year old male patient was admitted to the emergency room with severe abdominal pain, which has begun two days ago. On physical examination, tenderness was positive on palpation of the right lower abdominal quadrant and the patient was operated on with the diagnosis of acute appendicitis. Histopathological examination of the patient's appendectomy material revealed numerous parts of parasites resembling Enterobius vermicularis and slight mucosal erosion. On parasitological examination of the patient's stool, Taenia eggs and adult forms were determined. Antiparasitic therapy was started with niclosamide for taeniasis and albendazole for enterobiasis. Parasitic infections can mimic acute appendicitis clinically. Radiological and laboratory findings do not help to distinguish the diagnosis of acute appendicitis. In the histopathological examination of the appendix, the findings of acute inflammation of the appendix wall may not be defined. For patients with normal histopathological examination, screening for parasites should be done, and anti-parasitic treatment should be started after appendectomy.

Enterobius vermicularis: Can it be a possible pathogen in Bartholin gland abscess formation?

The most frequent disorders of the Bartholin glands are cysts or abscesses. Bartholin gland abscesses occur generally as a result of polymicrobial infections or agents that cause sexually transmitted diseases. But as far as we know, no parasite has been previously reported among the infectious agents that are detected from the abscesses of the Bartholin gland. Here, we report a 45-year-old woman, in the Bartholin abscess aspirate of whom Enterobius vermicularis eggs were detected in between the inflammatory infiltrate by cytological examination.