Cholinergic signaling plasticity maintains viscerosensory responses during Aspiculuris tetraptera infection in mice small intestine

Intestinal parasites alter gastrointestinal (GI) functions like the cholinergic function. Aspiculuris tetraptera is a pinworm frequently observed in laboratory facilities, which infests the mice cecum and proximal colon. However, little is known about the impact of this infection on the GI sensitivity. Here, we investigated possible changes in spontaneous mesenteric nerve activity and on the mechanosensitivity function of worm-free regions of naturally infected mice with A. tetraptera. Infection increased the basal firing of mesenteric afferent nerves in jejunum. Our findings indicate that nicotinic but not muscarinic receptors, similarly affect spontaneous nerve firing in control and infected animals; these axons are mainly vagal. No difference between groups was observed on spontaneous activity after nicotinic receptor inhibition. However, and contrary to the control group, during infection, the muscarinic signaling was shown to be elevated during mechanosensory experiments. In conclusion, we showed for the first time that alterations induced by infection of the basal afferent activity were independent of the cholinergic function but changes in mechanosensitivity were mediated by muscarinic, but not nicotinic, receptors and specifically by high threshold nerve fibers (activated above 20mmHg), known to play a role in nociception. These plastic changes within the muscarinic signaling would function as a compensatory mechanism to maintain a full mechanosensory response and the excitability of nociceptors during infection. These changes indicate that pinworm colonic infection can target other tissues away from the colon.

Extraintestinal oxyuriasis - report of three cases and review of literature

Extraintestinal oxyuriasis, in our experience with three affected women of fertile age, presented itself as a solitary fibrotic nodular lesion, with a varying location. The sites of location were: parietal peritoneum, serous surface of the uterus and wall of the uterine tube. The size of the nodules was 5 to 10 mm. Histologically, the lesions were hypocellular fibrotic nodules with a variable amount of neutrophils and amorphous eosinophilic material in the center, harbouring eggs of the parasite and remnants of pinworm cuticle. All three lesions were asymptomatic, only being discovered incidentally during the operations for unrelated conditions. Their peroperative recovery by a surgeon did not alter the course of surgery. These findings document the ability of pinworms to migrate into the abdominal cavity via the female genital tract.

Macrophage polarisation: an immunohistochemical approach for identifying M1 and M2 macrophages

Macrophage polarization is increasingly recognised as an important pathogenetic factor in inflammatory and neoplastic diseases. Proinflammatory M1 macrophages promote T helper (Th) 1 responses and show tumoricidal activity. M2 macrophages contribute to tissue repair and promote Th2 responses. CD68 and CD163 are used to identify macrophages in tissue sections. However, characterisation of polarised macrophages in situ has remained difficult. Macrophage polarisation is regulated by transcription factors, pSTAT1 and RBP-J for M1, and CMAF for M2. We reasoned that double-labelling immunohistochemistry for the detection of macrophage markers together with transcription factors may be suitable to characterise macrophage polarisation in situ. To test this hypothesis, we have studied conditions associated with Th1- and Th2-predominant immune responses: infectious mononucleosis and Crohn’s disease for Th1 and allergic nasal polyps, oxyuriasis, wound healing and foreign body granulomas for predominant Th2 response. In all situations, CD163+ cells usually outnumbered CD68+ cells. Moreover, CD163+ cells, usually considered as M2 macrophages, co-expressing pSTAT1 and RBP-J were found in all conditions examined. The numbers of putative M1 macrophages were higher in Th1- than in Th2-associated diseases, while more M2 macrophages were seen in Th2- than in Th1 related disorders. In most Th1-related diseases, the balance of M1 over M2 cells was shifted towards M1 cells, while the reverse was observed for Th2-related conditions. Hierarchical cluster analysis revealed two distinct clusters: cluster I included Th1 diseases together with cases with high numbers of CD163+pSTAT1+, CD68+pSTAT1+, CD163+RBP-J+ and CD68+RBP-J+ macrophages; cluster II comprised Th2 conditions together with cases displaying high numbers of CD163+CMAF+ and CD68+CMAF+ macrophages. These results suggest that the detection of pSTAT1, RBP-J, and CMAF in the context of CD68 or CD163 expression is a suitable tool for the characterisation of macrophage polarisation in situ. Furthermore, CD163 cannot be considered a reliable M2 marker when used on its own.

[Microstructural changes in the organs of the rabbit with passaluriasis]

The paper presents the data on morphofunctional changes in some rabbit organs (the liver, kidney, intestine, lung, heart) invaded with the nematode Passalurus ambiguus. The most profound inflammatory and dystrophic changes were found in the cecum which was a site of helminths. The signs of vacuolar dystrophy were also observed in the hepatic and renal parenchyma. There was activation of the immune system and mobilization of overall compensatory responses of the animals.

Impaired intestinal electrolyte transport in rats infested with the common parasite Syphacia muris

An incidentally discovered infestation with the nematode Syphacia muris of cecum and colon in spontaneously hypertensive (SHR) and normotensive control (WKY) rats was investigated over a two-year period. Infestation rates in WKY were higher than in SHR, while clinical signs as well as histological changes of colonic tissues were absent in both strains. In vivo net water absorption (microliter/hr/cm2) in control worm-free SHR turned into secretion in infested rats, ie, from 74.2 +/- 23.2 to -7.5 +/- 35.0 (P less than 0.001); this corresponded with a decrease in net absorption (mumol/hr/cm2) of Na from 18.5 +/- 2.4 to 9.3 +/- 4.3 (P less than 0.001) and of Cl from 14.0 +/- 3.2 to 3.2 +/- 5.7 (P less than 0.001). In WKY, net water absorption decreased from 112.2 +/- 23.2 to 48.0 +/- 25.1 (P less than 0.001) and Na and Cl absorption from 22.3 +/- 3.1 to 16.0 +/- 4.2 (P less than 0.005) and from 19.4 +/- 2.7 to 10.9 +/- 4.7 (P less than 0.005), respectively. Antihelminthic treatment with 0.007% pyrvinium pamoate in the ration (four weeks on, six months off) eradicated Syphacia muris in both rat strains. Body weight gain of young rats on normal and pyrvinium pamoate-substituted diet studied over 18 months was similar, indicating a good tolerance of the treatment. It is concluded that results obtained during comparative intestinal transport studies between SHR and WKY may not only be impaired but also significantly distorted by Syphacia muris infestation as SHR appear to be more susceptible to effects induced by this common parasite than WKY.

Enterobiasis: a histopathological study of 259 patients

Enterobius worms or their eggs, or both, are present in preserved tissue sections or tissue specimens of 259 patients whose medical records are on file at the Armed Forces Institute of Pathology, Washington D.C., U.S.A. The most common site of infection (86.5%) was found to be the lumen of the appendix, where the worms provoke no reaction. Of the 259 patients 11 (4.2%) had worms and/or eggs in granulomas of the abdominal and pelvic peritoneum, and an equal number had granulomas on the peritoneum of the salphinx or on the surface of the ovary. There were also ectopic worms and/or eggs in granulomas on the peritoneum of the small and large intestines (2.7%). These Enterobius granulomas form around degenerating adult worms, around discrete eggs, around clusters of eggs, and, we believe, also around the tracks of migrating worms. Three patients (1.2%) had worms in perianal abscesses. A necrotic granuloma, removed from the lung of one patient, surrounded a degenerating adult worm. This suggests that the worm, carried to the lung as an embolus, impacted in a pulmonary arteriole. A stool specimen of one patient contains eggs of Enterobius, and that of another patient contains an adult Enterobius. This is the largest recorded histopathological study of enterobiasis in man.

Enterobius egg granuloma of the vulva and peritoneum: review of the literature

Two cases of Enterobius granuloma containing eggs only are reported. The first case involved the vulva, where no such granuloma has been reported previously. The coexistence of peritoneal granuloma and rectal adenocarcinoma in the second case suggests the possibility of direct penetration of the damaged colonic wall by the parasite, as emphasized by several previous reports of neoplastic involvement and perforation of the intestinal wall in cases of ectopic infections. The diagnostic criteria of Enterobius eggs granuloma, which might be a diagnostic dilemma for pathologists who are not familiar with such criteria, are described herein.

Appendicitis and Enterobius vermicularis

A histologic examination was made of all appendices delivered to the Dept. of Pathology, Sundby Hospital, Copenhagen, in 1980-87, to ascertain the incidence of Enterobius vermicularis (pinworm) and the possible relation to acute appendicitis. Altogether 2267 appendices were examined, and E. vermicularis was identified in 4.1%. The highest incidence occurred in the 6- to 15-year age group. Infestation was more frequent in female than in male appendices, with the ratio of 1 male to 1.8 females, except in the 11- to 15-year age group, in which the ratio was 1. There was a highly significant difference in the incidence of E. vermicularis in normal appendices and in inflamed appendices, which may indicate that 1) the presence of E. vermicularis in the appendix can give the symptoms of acute appendicitis, or 2) E. vermicularis leaves or does not enter an inflamed appendix.

Pathology of tropical appendicitis

Over the past 25 years, 2921 appendicectomies were performed at this hospital. All were subjected to routine histopathological examination. In 95% of cases, histopathological examination did not add any further information but in 153 (5%) cases, clinically important pathological findings were detected for the first time. Seventy (2.3%) specimens showed typical evidence of tuberculosis. Parasitic infestation was detected in 75 (2.5%), including enterobiasis (1.4%), amoebiasis (0.5%), ascariasis (0.5%), ascariasis with trichuriasis (0.05%), and taeniasis (0.05%). Other lesions found were mucocele (0.1%) and carcinoid tumour (0.1%). It is concluded that routine histopathological examination of all appendicectomy specimens should be performed to avoid missing any clinically important and treatable condition.

[Oxyurid granuloma of the mesentery]

A 44-year-old woman presented with an acute abdominal syndrome associated with fever. Laparotomy revealed a mesenteric mass; pathology demonstrated a granuloma containing an adult threadworm (Enterobius vermicularis) and its eggs. Ectopic oxyuriasis is rare, and only three cases of peritoneal granuloma distant from the pelvis or the appendix have been reported previously. Our observation is the first case to which a clinical symptomatology could be ascribed. The pathogenesis and the treatment of this particular localization of oxyuriasis are discussed.

Hepatic granuloma resulting from Enterobius vermicularis

A nodule of the liver was incidentally noted during left colectomy for a large villous adenoma in a 74-year-old man. Microscopic examination disclosed a granuloma of the liver containing numerous Enterobius vermicularis ova and a cross-section of the nematode. This is the fourth reported case of hepatic oxyuriasis and the second case reported in North America.

Pinworm infestation of the genital tract

Extraintestinal enterobiasis has been reported in the vagina, endometrium, myometrium, ovary, fallopian tube and pelvic peritoneum. Gravid female pinworms may migrate from the perianal area to the vagina, ascend through the genital tract and exit through the fallopian tube to the peritoneum. Ectopic enterobiasis seldom causes clinical symptoms, but chronic granuloma formation may simulate other mass lesions in the pelvis.

Mast cell numbers in appendices with threadworm infestation

A study has been made of mast cells (MC) in surgically resected appendices using a long toluidine blue (LTB) staining method. The numbers of MC in measured areas of both mucosa and submucosa/muscularis were counted and comparisons made between 22 appendices containing threadworms and 22 which were histologically normal. There was considerable variation in MC numbers from case to case and the patients aged under 15 as a group had a higher mean number of mucosal MC than the older patients. The reasons for the high individual variation could not be identified from the histological sections, and no correlation was found between MC numbers and the presence of threadworms.

Invasion of human embryo by Enterobius vermicularis

Two Enterobius vermicularis organisms invading a macerated embryo 2 cm in length were found in the tissue from an endometrial curettage performed for missed abortion in a pregnant woman. Ova from the helminths were recovered from the vagina and endometrium of the patient. This most unusual case provides further evidence for the invading capacity of E vermicularis.

Folliculitis of the buttocks and pinworms. A case report

Folliculitis, both superficial and deep, has increased in frequency, particularly during the warm months of the year. The frictional trauma from tight-fitting jeans, with overhydration and maceration of the skin, has contributed to the increase. Folliculitis is usually accompanied by pruritus, but when pruritus precedes the folliculitis, there may be another cause in addition to the wearing of tight clothes. Such was the case in our patient who had anal pinworms (Enterobius vermicularis).

Perianal abscess due to Enterobius vermicularis. Report of a case

A case of recurrent perianal abscess caused by Enterobius vermicularis infestation of the anal canal and glands in an 11-year-old boy is reported.

Pinworm granuloma of the liver

A granuloma containing Enterobius vermicularis was found in the liver of a 62-year old woman from Arkansas who had a 4-year history of recurrent surgery for adenocarcinoma of the colon. Hematogenous spread and direct penetration of the liver preceded by either invasion of the peritoneum through unhealthy or traumatized intestinal tissue, or from migration up the genital tract are the infective mechanisms considered. This type of parasitic liver lesion is the third reported case, the first in North America, and the first in a female.

[The chronically altered appendix in children. Cooperative work of the Austrian Society for Pediatric Surgery]

In this multicentric study the anamnestic data and parents questionaires of 2-29 children were evaluated, whose appendix vermiformis at the time of operation showed no signs of inflammation. 31,1% macroscopically showed cicatrisation or fasciation, in 13,7% other enteral or gynaecological (1%) findings were present. In 1194 of the cases of patho-histological examination of the appendix had been made of which 36.4% were negative, 37.7% showed cicatrisation, 15,0% oxyuriasis and 10,4% coproliths. In the discussion of the significance of the chronically altered non-inflamed appendix we compared patients with and without macroscopical or microscopical alterations. We came to the conclusion that the probability-index as to sex, duration of symptoms, complexity of symptoms, incidence of postoperative well-being, proved the chronically altered appendix not to be an illness per se, but the result of spontaneously arrested inflammation. Since the rate of children admitted with a perforated appendix is high (15-20%) in comparison with the rate of complications after removal of non-inflamed appendices (2,9%), we believe that according to the diagnostical problems the principle can be maintained: in dubio pro operatione.

Ovarian enterobiasis--a proposed pathogenesis

An Enterobius vermicularis within the parenchyma of the ovary is a rare phenomenon. We present a case and propose that the gravid female, after wandering from perianal skin into the vagina and then through the female genital passages, arrived at the ovary and entered a recently ruptured graafian follicle.

Oxyuris granulomas of pelvic peritoneum and appendicular wall

Infestation with Enterobius (Oxyuris) vermicularis is very common but seldom produces lesions and even more rarely causes granulomas. Two cases of oxyuris granulomas/nodules), one in the serosa of ovaries and left fallopian tube in a female of 32-years and the other in the submucosa of the appendix in a 10-year old girl are identified by the presence of true necrotizing granulomas containing the parasite. The pathogenesis and differential diagnosis of abdominal granulomas is discussed.

Unilateral salpingitis due to Enterobius vermicularis

A case of perforated unilateral salpingitis in which Enterobius vermicularis ova were identified in the inflammatory process is reported. Arguments for considering the parasite to be of etiologic significance in the production of the pathologic changes and clinical symptoms are presented. The infrequent occurrence of symptoms associated with ectopic localization of Enterobius vermicularis is emphasized by a review of the literature.

Ectopic Enterobius vermicularis

Enterobius vermicularis (the pinworm) commonly infests the lumen of the intestine but on rare occasions has been found in the wall or in the tissues outside the gastrointestinal tract. Three such patients have been encountered in whom Enterobius vermicularis was found in the wall of the colon, in the retrocaecal tissues, and on the peritoneum. The pathological lesions and their relationship to the clinical features are discussed. A brief review of the literature is given. It is concluded that Enterobius vermicularis can only penetrate the wall of the gastrointestinal tract if this is diseased. Once in the tissues the worms can cause an inflammatory reaction simulating carcinoma and Crohn's disease, and, by perforation of the intestine, cause a generalized peritonitis.

Pathological effects of oxyuriasis in the laboratory mouse

In mice with oxyuriasis a slight inflammatory reaction occurs in the colonic mucosa. Adult Aspicularis tetraptera can penetrate the colon, thus causing inflammation and a granulomatous reaction in and outside the intestinal wall. Immature parasites can occur in the colonic glands and in the propria mucosa.