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.

Morphology, genetic characterization and molecular phylogeny of pinworm Skrjabinema longicaudatum n. sp. (Oxyurida: Oxyuridae) from the endangered Tibetan antelope Pantholops hodgsonii (Abel) (Artiodactyla: Bovidae).

BACKGROUND: The Tibetan antelope Pantholops hodgsonii (Abel) (Artiodactyla: Bovidae) is an endangered species of mammal endemic to the Qinghai-Tibetan Plateau. Parasites and parasitic diseases are considered to be important threats in the conservation of the Tibetan antelope. However, our present knowledge of the composition of the parasites of the Tibetan antelope remains limited. METHODS: Large numbers of nematode parasites were collected from a dead Tibetan antelope. The morphology of these nematode specimens was observed using light and scanning electron microscopy. The nuclear and mitochondrial DNA sequences, i.e. small subunit ribosomal DNA (18S), large subunit ribosomal DNA (28S), internal transcribed spacer (ITS) and cytochrome c oxidase subunit 1 (cox1), were amplified and sequenced for molecular identification. Moreover, phylogenetic analyses were performed using maximum likelihood (ML) inference based on 28S and 18S + 28S + cox1 sequence data, respectively, in order to clarify the systematic status of these nematodes. RESULTS: Integrated morphological and genetic evidence reveals these nematode specimens to be a new species of pinworm Skrjabinema longicaudatum (Oxyurida: Oxyuridae). There was no intraspecific nucleotide variation between different individuals of S. longicaudatum n. sp. in the partial 18S, 28S, ITS and cox1 sequences. However, a high level of nucleotide divergence was revealed between the new species and its congeners in 28S (8.36%) and ITS (20.3-23.7%) regions, respectively. Molecular phylogenetic results suggest that the genus Skrjabinema should belong to the subfamily Oxyurinae (Oxyuroidea: Oxyuridae), instead of the subfamily Syphaciidae or Skrjabinemiinae in the traditional classification, as it formed a sister relationship to the genus Oxyuris. CONCLUSIONS: A new species of pinworm Skrjabinema longicaudatum n. sp. (Oxyurida: Oxyuridae) is described. Skrjabinema longicaudatum n. sp. represents the first species of Oxyurida (pinworm) and the fourth nematode species reported from the Tibetan antelope. Our results contribute to the knowledge of the species diversity of parasites from the Tibetan antelope, and clarify the systematic position of the genus Skrjabinema.

Morphological and molecular characterization of Aspiculuris tetraptera (nematoda: Heteroxynematidae) from Mus musculus (rodentia: Muridae) in Saudi Arabia.

Aspiculuris tetraptera a pinworm of mice, is an important parasite in institutions with mice colonies for both research and teaching purposes. Infection with this parasite has impact on biomedical research. This is likely due to the availability of the parasite's eggs in the environment, therefore can easily be transmitted and infection is generally asymptomatic. No information regarding the prevalence, morphology or phylogeny is available on A. tetraptera from Saudi Arabia. A group of 50 laboratory mice were investigated for the presence of A. tetraptera. Worms were described morphologically and molecular characterization was attempted using 18S rRNA and Cytochrome Oxidase Subunit I genes. The prevalence of A. tetraptera infestation in the laboratory mice examined was found to be 46%. Morphological description indicated that the worms belong to A. tetraptera and this was confirmed by molecular characterization. Both regions studied have shown that the worm under investigation grouped with A. tetraptera. 18S rDNA sequences obtained in the present study showed high identity with sequences from A. tetraptera while Cytochrome c Oxidase subunit I gene (COI) sequences showed intraspecific variation resulted into two haplotypes from the isolates in the present study. A. tetraptera was recorded for the first time from Saudi Arabia. Molecular characterization has shown, based on the COI sequences, that the Saudi isolates of A. tetraptera are distinct.

First report in pre-Columbian mummies from Bolivia of Enterobius vermicularis infection and capillariid eggs: A contribution to Paleoparasitology studies.

OBJECTIVE: This study was designed to search for ancient parasites in abdominal content and coprolites from Bolivian mummies. MATERIALS: Twelve mummified individuals from the Andean highlands, housed at the National Museum of Archaeology (MUNARQ) in La Paz, Bolivia. METHODS: Microscopic analysis of rehydrated samples (coprolites and abdominal content), following Lutz's spontaneous sedimentation technique. RESULTS: Eggs of Enterobius vermicularis were identified in coprolites from one mummy, and capillariid eggs in the organic abdominal content from another individual. CONCLUSIONS: This is the first evidence of ancient intestinal parasites in Bolivian mummies. SIGNIFICANCE: This pioneering study focused on the search of ancient intestinal parasites in human remains of the Bolivian Andes and contributes to greater knowledge of paleoparasitology in South America. LIMITATIONS: All mummies in the MUNARQ belonged to the Andean Bolivian highlands (post-Tiwanaku era or Late Intermediate Period), although the exact provenance of the material and the associated contexts are not well recorded. SUGGESTIONS FOR FURTHER RESEARCH: Considering the great number of well-known archaeological sites and other unexplored sites in Bolivia, in addition to large collections in museums, further paleopathological and paleoparasitological molecular studies in mummies and skeletons are called for.

The Distribution of Intestinal Parasites in Patients Presenting to a University Hospital in Istanbul: A Seven-year Retrospective Analysis

Objective: The purpose of this study was to determine the intestinal parasite distributions in patients who applied to the Parasitology Laboratory of Istanbul University-Cerrahpasa, Cerrahpasa Medical Faculty, by evaluating the parasites retrospectively. Methods: Normal saline and stool lugol were applied for direct examination of stool samples that were sent for parasite examination; cellophane band samples were evaluated microscopically. The samples suspected to have protozoa were evaluated using modified acid fast and trichrome staining methods. We evaluated the parasitological examination results of patients who applied to our laboratory between January 2012 and December 2018. Results: A total of 2.96% of the 20,948 patients who applied had parasites in their faeces. Blastocystis spp. was detected at the highest rate (63.23%), followed by Giardia intestinalis (17.26%), Enterobius vermicularis (12.58%), Taenia saginata (2.42%), Cryptosporidium spp. (1.94%) and Entamoeba histolytica/dispar (1.45%). Conclusion: Although the prevalence of intestinal parasitic infections has decreased when compared to previous years, it still remains important. For this reason, solving infrastructure problems, providing information on personal hygiene and sanitation rules are among the most important tasks needed to reduce the prevalence of intestinal parasites.

Impact of Enterobius vermicularis infection on biochemical parameters in the blood of children in Erbil Province, Iraq.

BACKGROUND: Enterobius vermicularis is an intestinal helminthic parasite that causes a gastrointestinal infection called enterobiasis. Children are more susceptible to infection than adults. The current study aimed to explore the prevalence of E. vermicularis infection among children in Erbil City concerning demographic factors and certain blood parameters. METHODS: A cross-sectional and analytical study was conducted on 505 children (3-10 years). Cellophane tape samples and blood samples were taken from participants. The cellophane tape samples were examined microscopically, whereas blood samples were examined using the auto-analyzer and Cobas. RESULTS: The overall prevalence of E. vermicularis infection was 27.13%, and the infection rate was non-significantly (P = 0.371) higher in females (28.85%) than in males (25.31%). The incidence of enterobiasis was directly proportional to family size. This study demonstrated that the mean serum total protein and iron levels were significantly decreased in infected children, while other trace element levels were not significantly affected. CONCLUSIONS: The prevalence of E. vermicularis is relatively lower than that in previous studies. Serum total protein and iron levels significantly decreased in the enterobiasis-positive group.

The Distribution of Pathogenic Intestinal Parasites in Sivas Cumhuriyet University Faculty of Medicine Research and Application Hospital between 2006-2018

Objective: The aim of this study was to determine the distribution of intestinal parasites in patients admitted to our hospital with gastrointestinal complaints in our city harboring sociocultural and economic changes, and to show the relationship between these parasites and variables such as age, sex and year. Methods: The distribution of intestinal parasites in patients who suffered from gastrointestinal symptoms and were referred to our microbiology/parasitology laboratory from various clinics of the Sivas Cumhuriyet University Training and Research Hospital between January 2006 and December 2018 was determined. After macroscopic examination, 19,760 stool specimens were examined with Nativ-lugol, if necessary, flotation, sedimentation, trichrome and modified acid-fast, Certest Combo Card test Crypto + Giardia + Entamoeba (CerTest Biotec S.L., SPAIN) methods and 5,814 cellophane tape samples were examined with direct microscopy and the results were evaluated retrospectively. Results: Three protozoa and six helminth species were identified in the samples studied. The most frequent parasite was found to be Giardia intestinalis (6.9% n=1.363) from protozoa and Enterobius vermicularis (10.8% n=627) from helminths. Entamoeba histolytica/dispar (1.5% n=289), Cryptosporidium parvum (0.3% n=53), Ascaris lumbricoides (0.2% n=41), Trichuris trichiura (0.1% n=23), Hymenolepis nana (0.1% n=21), Taenia saginata (2.1% n=299) and Dicrocoelium dendriticum (0.01% n=1) were among other intestinal parasites. Conclusion: Between 2006-2018, while decreases in soil-borne parasitoses were observed, there was no statistically significant decrease in annual positive case rates. Despite the development of the infrastructure, parasitoses transmitted by lack of sanitation/cleaning, are still important in our province.

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.

Perforation of the Small Intestine with Acute Peritonitis Caused by Enterobius Vermicularis.

Perianal and perineal pruritus is often associated with Enterobius vermicularis in children. Although this roundworm is common in pediatric practice, most doctors are unaware that it can cause appendicular colic with/or appendicitis, severe urogenital complications, bowel perforation, and peritonitis. We report a case of a young male who presented with signs and symptoms of acute peritonitis. Dur-ing the operation, perforation of the jejunum with a purulent exudate under the transverse colon, a left lateral canal, a Douglas cavity were found as well as single enlarged mesenteric lymph nodes. Histological studies detected Enterobius vermicularis in the lumen of the appendix and jejunum, as well as in the purulent exudate in the intestinal wall and serosa. A mesenteric lymph node, histologically presented with chronic nonspecific lymphadenitis. In conclusion, infection with Enterobius vermicularis should be considered in peri-tonitis, appendicitis, and enlarged mesenteric lymph nodes, especially in young patients.

Preschool Girl With Vaginal Bleeding Due to Pinworm Endometritis.

Genital tract bleeding in prepubertal girls is a rare clinical condition, which can occur for multiple reasons. It frequently generates anxiety in the family and in health care professionals. A thorough anamnesis and careful genital inspection can give important diagnostic hints; however, there are cases in which the cause remains doubtful and a complete gynecological evaluation (including cultures and vaginoscopy) is necessary. Therefore, the attending physician should always consider less frequent diagnoses in order to perform the necessary studies in a sequential and rational manner. We present the case of a preschool girl with vaginal bleeding due to pinworm endometritis, which, to our knowledge, has never been reported before as a cause of genital bleeding in prepubertal girls.

Enterobious vermicularis induced infectious keratitis following penetrating keratoplasty.

A 28-year-old man with a prior history of penetrating keratoplasty in the left eye for total corneal melt presented with a 3-day history of a red, painful left eye. On examination, he was found to have graft infiltrates. Microscopic examination of wet mount preparation of corneal scrapings revealed the presence of embryonated eggs of E. vermicularis. Cellophane (scotch) tape preparation from perianal region also revealed embryonated eggs of E. vermicularis as well as live adult worms. Ocular and adnexal involvement by E. vermicularis is extremely rare. Here, we report the first case of infection of a corneal graft with E. vermicularis.

A new genus and species of pinworm (Nematoda, Oxyuridae) from the gray mouse opossum, Tlacuatzin canescens.

Tlacuatzoxyuris simpsoni n. gen. n. sp. is described from the cecum of the gray opossum, Tlacuatzin canescens, a species endemic to the deciduous dry forest of Mexico. The digestive tracts of four specimens were examined for parasites; three of these were archived in the American Museum of Natural History and one was a live capture. Relative to the other four monotypic genera of pinworms known to infect opossums, the new genus is diagnosed on the basis of a round cephalic plate with a semicircular stoma surrounded by a rim. In addition, males feature a prominent cephalic vesicle not fully developed in females, accounting for sexual dimorphism. The new species includes small worms that feature a conspicuous, not reticulated cephalic vesicle and semicircular stoma and lateral alae with two crests. In addition, the postcloacal cuticle of males features a small area with ornamentation between cloaca and submedial papillae. Finally, both spicule and gubernaculum are relatively short. Although the eggs of Tlacuatzoxyuris n. gen. are unknown, the conspicuous differences in traits used in the diagnosis of genera prompted us to propose a new genus for the new species. This is the first species of Oxyuridae reported in mouse opossums outside South America, and the fifth species of the family occurring in didelphimorph marsupials. This is an example of the usefulness of documenting the diversity of parasites associated with this unique clade of mammals through the examination of preserved tissues.

Intestinal parasitic infections and associated factors in children of three rural schools in Colombia. A cross-sectional study.

Rural children are one of the populations that are most vulnerable to gastrointestinal parasite infections. Such diseases decrease the quality of life and result in growth and cognitive delays in the long term. This cross-sectional study was conducted to determine the frequency of intestinal parasite infections among rural schoolchildren in the municipality of Apulo, Colombia. A total of 97 stool samples from children aged between 5 and 15 years were collected and examined via direct light microscopy. Microscopic examination was repeated with sediments obtained using a fecal parasite concentrator, and the Kato-Katz test was performed. Frequency of intestinal parasite infection was 100%. Endolimax nana (77.35%), Blastocystis sp. (71.1%), Giardia intestinalis (39.1%), Entamoeba coli (25.7%), and the Entamoeba histolytica/dispar/moshkovskii complex (9.2%) were the most prevalent protozoa. Trichuris trichiura was the most prevalent helminth (12.3%), followed by Enterobius vermicularis (6.15%) and Ascaris lumbricoides (5.1%). Among the analyzed associated factors, consumption of untreated water increased the risk of acquiring pathogenic intestinal parasites. Finally, because G. intestinalis was the most prevalent pathogenic protozoan, molecular analysis was conducted to establish genetic assemblages and subassemblages of Giardia through sequence-based genotyping of the glutamate dehydrogenase, triose phosphate isomerase, and beta-giardin genes. A total of 14 G. intestinalis-positive samples were genotyped, which revealed the presence of subassemblages AI (n = 1), AII (n = 7), BIII (n = 2), BIV (n = 2), and BIII/BIV (n = 1) as well as a mixed subassemblage AII + BIII (n = 1). Our results indicate that gastrointestinal parasite infections in the tested population were mainly caused by suboptimal water quality. Moreover, molecular typing of G. intestinalis suggested contamination of water by animal- and human-derived cysts.

Enterobius vermicularis infection: prevalence and risk factors among preschool children in kindergarten in the capital area, Republic of the Marshall Islands.

BACKGROUND: Enterobius vermicularis (pinworm) is one of the most common human parasitic helminths, and children are the most susceptible group. Some behavioral and environmental factors may facilitate pinworm infection. In the Republic of the Marshall Islands (RMI), the status of pinworm infections among children remains unknown. METHODS: In Majuro City, there are 14 kindergartens with a total of 635 preschool children (PSC) whose age range of 5~6 years. The present investigation attempted to determine the pinworm prevalence and associated risk factors as well as investigate whether eggs contaminated the clothes of PSC or the ground and tables in classrooms of 14 kindergartens. Informed consent form and a self-administered questionnaire were given to parents prior to pinworm screening. Perianal specimens were collected by an adhesive scotch tape method, and clothing of belly and hip sites and the ground and tables of the classrooms were inspected using a cellophane tape method to detect any eggs contamination. RESULTS: In total, 392 PSC (5.28 ± 0.56 yrs. old) participated in this project. The overall prevalence of pinworm infection was 22.4% (88/392). Boys (24.5%) had higher prevalence than girls (20.31%) (p = 0.32). PSC aged > 5 years (32.77%) showed a significantly higher prevalence than those aged ≤5 years (17.95%) (p = 0.01). A univariate analysis indicated that PSC who lived in urban areas (22.95%) had a higher prevalence than those who lived in rural areas (20.69%) (p = 0.69). The employment status of the parents showed no association with the pinworm infection rate (p > 0.05). A logistic regression analysis indicated that "having an older sister" produced a higher risk of acquiring pinworm infection for PSC compared to those who did not have an older sister (OR = 2.02; 95%CI = 1.05~3.88; p = 0.04). No significant association between various other risk factors and pinworm infection was found (p > 0.05). Also, no eggs contamination was found on the clothes of the belly and hip sites or on the ground and tables in the 14 kindergartens. CONCLUSIONS: Mass screening and treatment of infected PSC are important measures in pinworm control in the RMI.