Transverse Myelitis in the Setting of Enterobius vermicularis (Pinworm) Infection: Case Report.

Myelitis is a rare inflammatory myelopathy, and known associated etiologies only account for a small number of causes. A significant percentage of cases have an unknown etiology and are considered idiopathic. With 64% to 68% of cases fitting into the idiopathic category, helminth infections, and specifically pinworm parainfections, should be considered in cases that would otherwise be classified as idiopathic. This case report outlines a pediatric patient diagnosed with myelitis given her progressive weakness, fussiness, refusal to bear weight as well as magnetic resonance imaging (MRI) demonstrating T2-hyperintense signal and/or T1 gadolinium enhancement, and/or positive cerebrospinal fluid (CSF) inflammatory markers. This patient had a negative evaluation for typical known etiologies for myelitis including no signs of multiple sclerosis and neuromyelitis optica spectrum disorder on brain MRI, oligoclonal banding and aquaporin-4 autoantibodies, and no evidence of bacterial or viral meningitis given normal cell counts and cultures in CSF. She was found to have a pinworm infection, suggesting a parasitic parainfectious etiology of her myelitis. This case outlines the first case noting the correlation between myelitis and pinworm infection in a pediatric patient.

Enterobius vermicularis (Pinworm) Appendicitis: The Real Vermiform Appendix.

Enterobius vermicularis is the most common helminthic infection in the United States, infecting an estimated 40 million persons. A rare complication of E. vermicularis infestation is appendicitis. The diagnosis must be considered during pathologic examination to ensure appropriate treatment with anti-helminthic therapy.

Enterobius vermicularis in Brazil: An integrative review.

Enterobius vermicularis, an intestinal helminth, is transmitted through the ingestion of eggs found in food, water, dust, or other fomites, including infected individuals. This review aimed to examine the frequency and distribution of E. vermicularis infections in Brazil between 1991 and 2022. The conducted bibliographic survey revealed that the frequency of E. vermicularis infections in Brazil ranged from 0.1 to 26.1%, depending on factors such as population ethnicity, individual age group, geographic area, time frame, and diagnostic method. However, these findings were based on a limited number of publications, suggesting that the actual prevalence rates of E. vermicularis infection may still be unknown and potentially underestimated.

Genotype Distribution of Enterobius vermicularis Isolates from Northwest Provinces of Iran.

Background: Human infection with Enterobius vermicularis occurs worldwide. The most common clinical manifestation of a pinworm infection is an itchy anal region. This parasite is incidentally found in appendicitis. This study aims to characterize and genotype this parasite from different samples inferred by mt-DNA. Methods: Forty appendectomies for acute clinical appendicitis, 40 positive scotch-tape samples, and 10 adult females worm isolated from patients. Genetic differentiation, haplotype differences, and isolates population structure were analyzed based on the cytochrome c oxidase subunit I (cox1) gene. Results: It has been demonstrated that all isolations in the appendectomies specimens are similar, and the genetic difference divergence is seen in adult worm specimens. The neutral indices of the samples did not show a significant difference and show that there is no intra-specific and population distribution diversity. Conclusion: Our results show different haplotypes in the B type of E. vermicularis population and add new information about genotyping of these parasites in Iran. In comparison with other studies, intra-specific variation of this parasite from Iran was observed.

Positive rates for Enterobius vermicularis eggs among preschool children in Yeosu-si, Jeollanam-do, Korea (2017-2021).

This study aimed to evaluate the positive rates for Enterobius vermicularis eggs among preschool children in Yeosu-si, Jeollanam-do, the Republic of Korea (Korea) over a period of 5 years (2017-2021). Perianal swab samples, obtained using cellotape, from 10,392 preschool children in 26 districts were examined microscopically for E. vermicularis eggs. The test results were notified through the local health center, and the families of children who tested positive were advised to provide them anthelmintics treatment. The annual positive rates were 5.0%, 5.2%, 4.4%, 2.2%, and 1.0% in 2017, 2018, 2019, 2020, and 2021, respectively. The overall positive rate was higher in boys than in girls (P< 0.05), and children aged 5-7 years were at a higher risk of being infected than those aged 0-4 years (P< 0.05). Although the rates of infection by E. vermicularis in the survey area, Yeosu-si, were still in the 1% range , the results of this study suggest that they can be significantly reduced through continuous intervention centered around the test-treatment strategy.

Clinicopathological Assesment in Patients with Enterobius vermicularis Infection

OBJECTIVE: Enterobius vermicularis is a common gastrointestinal parasite. Acute appendicitis is one of the most common clinical conditions requiring surgical intervention. The coexistence of enterobiasis and acute appendicitis has attracted the attention of researchers for a long time. In this article, it is aimed to present the characteristics of enterobiasis cases detected in appendectomy specimens in a tertiary healthcare institution. In addition, it is aimed to reveal the differences by comparing the cases diagnosed with acute appendicitis without enterobiasis. METHODS: All cases operated for acute appendicitis between January 1, 2008 and December 31, 2021 were retrospectively evaluated through the hospital registry system. The cases with histopathologically determined E. vermicularis were reviewed and a study group was formed. The control group consisted of patients diagnosed with acute appendicitis for reasons other than enterobiasis, matched with the study group in terms of age and gender. Complete blood count, C-reactive protein (CRP) ultrasonography evaluations were compared between the two groups. RESULTS: During the study period, 3.650 appendectomy materials were examined; E. vermicularis was detected in 1.32% (n=48) cases, and acute appendicitis was present in 33.33% (n=16) of the cases. Lymphoid hyperplasia was the most common histopathological change in the study group (n=25; 52.08%). When compared to the control group, leukocyte, neutrophil, CRP, ultrasonographic appendix diameter values were found to be significantly higher in the control group, and the percentage of eosinophils in the study group (p<0.0001; p<0.0001; p<0.0001; p<0.0001; p=0.001; respectively). CONCLUSION: Enterobiasis is a common parasite especially in children. Rarely, it can be seen in patients with acute appendicitis. Histopathological evaluation is necessary to ensure a safe surgical procedure and to complete the treatment with anthelmintic drugs. Enterobiasis should be kept in mind in cases when the acute phase response is lower than expected.

Eosinophilia and potential antibody cross-reactivity between parasites in a child with pinworm and immune dysregulation: a case report.

BACKGROUND: Intestinal parasitic infections are common in humans, especially among young children. These conditions are often asymptomatic and self-limiting, and diagnosis is mainly based on the search for ova and parasites in the stools since serology may be biased due to cross reactivity between parasites. Pinworm is common in children and is not usually associated with hypereosinophilia; adhesive-tape test is the gold standard testing for the microscopic detection of Enterobious vermicularis (Ev) eggs. CASE PRESENTATION: A 13-year-old boy was referred due to a self-resolving episode of vomiting and palpebral oedema after dinner, together with a history of chronic rhinitis, chronic cough, absolute IgA deficiency and Hashimoto's thyroiditis and hypereosinophilia (higher value = 3140/µl). On evaluation we detected only palpable thyroid and hypertrophic nasal turbinates. Food allergy was excluded, but skin prick tests showed sensitization to house dust mites and cat epithelium and spirometry showed a marked obstructive pattern with positive bronchodilation test prompting the diagnosis of asthma for which maintenance inhaled treatment was started. Chest x-ray and abdomen ultrasound were negative. Further blood testing showed positive IgG anti-Echinococcus spp. and Strongyloides stercoralis and positive IgE for Ascaris, while Ev were detected both by the adhesive tape test and stool examination, so that we made a final diagnosis of pinworm infection. Three months after adequate treatment with pyrantel pamoate the adhesive-tape test turned out negative and blood testing showed a normal eosinophil count. The child later developed also type 1 diabetes. CONCLUSIONS: We suggest the need to investigate for enterobiasis in children with hypereosinophilia and to consider autoimmunity as a potential confounding factor when interpreting serology for helminths.

Detection of Enterobius vermicularis in archived formalin-fixed paraffin-embedded (FFPE) appendectomy blocks: It's potential to compare genetic variations based on mitochondrial DNA (cox1) gene.

Acute appendicitis represents one of the most common causes of emergency abdominal surgery worldwide. Meanwhile, Enterobius vermicularis has been suggested as one of the probable causes of appendicitis. In this study, the morphological characteristics of the remnant pinworms and pathologic changes were explored in old-archived FFPE tissues of appendectomies. Moreover, we provide the first molecular identification, genetic, and haplotype variation of this nematode from the old-archived FFPE tissue section of appendectomy using the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. Seventeen FFPE appendectomies with E. vermicularis infection, stored over 12-22 years, were collected from two different geographical areas of Iran. In the histopathological examination, tissue changes were observed in thirteen cases (76.4%) and inflammation in four blocks (23.5%). After DNA extraction, the cox1 gene was amplified in twelve (70.6%) cases using the nested polymerase chain reaction (PCR). Phylogenetic analysis and a median-joining network of 78 available cox1 sequences of E. vermicularis revealed 59 haplotypes. We identified five haplotypes that fell into type B. All Haplotypes are novel except for two haplotypes, Hap32 and Hap37, identical to E. vermicularis sequences from Iran, Greece, and Germany. The ranges of diversity distance and haplotype diversity within the isolates were 0-1.9% and HD:0.643-0.667, subsequently. Overall, the absence of inflammation or even tissue changes in some sections can suggest the possible non-inflammatory role of E. vermicularis in appendicitis. Although FFPE material suffers from PCR inhibition, we could successfully use nested PCR to characterize E. vermicularis in old-archived appendectomy blocks and suggest this method as a complementary diagnosis technique in pathology. While the predominant type was B in the Middle East and Europe, further studies on a larger sample size from different geographical regions could probably confirm the results obtained in the present study.

[Multilocular hepatic masses due to Enterobius vermicularis]. / Multilokuläre hepatische Raumforderungen durch Enterobius vermicularis.

Infestation with Enterobius vermicularis involving extraintestinal manifestation is rare. In a 50-year-old man with lower abdominal pain, computed tomography led to a suspected diagnosis of sigmoid carcinoma with liver metastasis. After ruling out colon cancer by endoscopy, laparoscopic resection of one suspected tumor nodule in the liver was performed. Histopathological examination revealed parasitic granulomas containing pinworms. Hematogenous migration was postulated in the setting of phlebitis with thrombosis of the inferior mesenteric vein.

Seeds or Parasites? Clinical and Histopathological Features of Seeds and Parasites in the Appendix.

OBJECTIVE: Parasites and plant seeds may both be found in appendectomy specimens. Each plant seed has a different appearance and can thus exhibit wide variations under the microscope. Fragmented seeds may histologically mimic parasites. The differential diagnosis between seeds and parasites can be challenging in such cases. This study aimed to determine the incidence of parasites, seeds, and foreign bodies in appendectomy materials and highlight the most characteristic histopathological features associated with these structures. MATERIAL AND METHOD: In this study, pathology slides of 9,480 patients, who underwent appendectomy between 2010 and 2021, were reviewed, and cases that contained parasites, seeds, or foreign bodies were identified. We reviewed the literature on seeds and parasites in appendectomy specimens. RESULTS: Parasites were observed in 56 (0.6%) cases. Of these cases, 45 had Enterobius vermicularis (80%), and 11 had Taenia subspecies (20%). Plant seeds were observed in 47 cases (0.5%), and were macroscopically recognizable in 5 of them as olive, lemon, and cherry seeds. Parasites and seeds were usually observed in the lumen of appendix vermiformis, filled with abundant fecal materials. CONCLUSION: Seeds are seen in approximately 0.5% of the appendectomy specimens. Though rarely seen, the fragmented seed appearance may cause diagnostic difficulties. In this context, the key morphological features of parasites and plant seeds outlined in this study may be helpful in their differential diagnosis.

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.

Is pinworm infection still a public health concern among children in resource-rich regions? Trends in pinworm infection prevalence and associated factors among children in Hualien County, Taiwan: a retrospective cross-sectional study.

BACKGROUND: Enterobius vermicularis (pinworm) is a common intestinal parasitic infection in children. A gradual decrease in the prevalence of pinworm infection has been noted in resource-rich settings, such as Taiwan. However, the influence of sociodemographic factors on the temporal trend in pinworm infection rates in children under the current pinworm infection prevention policy in Taiwan is not well characterized. This study aimed to evaluate the trend of pinworm infection prevalence and the associated factors among children in Hualien County, Taiwan. METHODOLOGY: In this retrospective cross-sectional study, we included a total of 56,197 students (aged 6-10 years) in grades 1 and 4 in Hualien in 2009-2018. Children were screened for pinworm infection using adhesive cellophane perianal swabs in the routine student health examination. Logistic regression was conducted to evaluate the factors associated with pinworm infection. Associations between dependent and independent variables were measured by odds ratios. The Cochran-Armitage test was used to assess whether there were significant trends in different stratifications. Variables with P-values < 0.05 were considered statistically significant. RESULTS: A total of 56,197 school-age children from grades 1 and 4 during 2009-2018 were included. Young age and male sex were risk factors for pinworm infection (P < 0.001). A negative correlation between body mass index and enterobiasis was observed, and decreased pinworm infection was noted during the study reference period. Children living in suburban and rural areas had higher odds of having a pinworm infection than those living in urban areas (P < 0.001). A significant decrease in the overall prevalence rate of pinworm infection was observed among children in 2009-2018 (P < 0.001). However, there was no obvious change in the pinworm infection rate in rural areas during this period (P = 0.953), and it was higher than that in urban and suburban areas. CONCLUSIONS: The overall prevalence of pinworm infection gradually decreased from 2009 to 2018 among school-age children in Hualien. However, there was no declining trend in pinworm infection in rural areas. Young age, male sex, and rural residence were significantly associated with pinworm infection. Pinworm infection remains a major public health concern among children in rural areas of Hualien.

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.

Knowledge and Practice of Pinworm Infection in Preschool Children, Jiangsu Province, China, 2019-2020.

We conducted a two-year (2019-2020) longitudinal study in Jiangsu Province, China to analyze risk factors of pinworm infection and evaluate the effect of behavior change communication-based (BCC-based) interventions in preschool children. The positive rate of pinworm infection was higher in private preschool (2%) than in public preschool (0.24%). Poor sanitation behaviors were risk factors among private preschool children. BCC-based intervention could improve knowledge and practice and reduce pinworm infection. This study may help fill in gaps in pinworm control. (Am J Public Health. 2022;112(12):1716-1720. https://doi.org/10.2105/AJPH.2022.307067).

Prevalence and genetic analysis of Enterobius vermicularis in schoolchildren in lower northern Thailand.

Enterobius vermicularis, a nematode parasite with a global distribution causes enterobiasis in schoolchildren and is considered a neglected parasite. An understanding of the prevalence and genetic diversity of enterobiasis is crucial for appropriate control measures. Therefore, the objectives of this research were to study the prevalence and genetic diversity of E. vermicularis in schoolchildren from lower northern Thailand, based on cytochrome c oxidase subunit I (COI) and internal transcribed spacer 2 (ITS2) sequences. Using the scotch tape technique, 7.4% (188/2544) of schoolchildren from 21 primary schools were found positive for E. vermicularis eggs, which is a relatively low infection rate. Phylogenetic trees of partial COI sequences (397 bp) revealed similar topologies using maximum likelihood (ML) and neighbor-joining (NJ) methods and identified E. vermicularis type A (105 sequences) and B (1 sequence). Haplotype network analysis of the COI sequences demonstrated a high haplotype diversity (Hd = 0.9028). In contrast, phylogenetic analysts of a 343 bp region of the ITS2 locus (52 sequences) revealed a monophyletic group. More sequence analyses of E. vermicularis from humans and other hosts in Thailand are necessary to better understand the genetic diversity of this parasite.

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.