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Ascariasis is the most prevalent helminth affecting approximately 819 million people worldwide. The acute phase of Ascariasis is characterized by larval migration of Ascaris spp., through the intestinal wall, carried to the liver and lungs of the host by the circulatory system. Most of the larvae subsequently transverse the lung parenchyma leading to tissue injury, reaching the airways and pharynx, where they can be expectorated and swallowed back to the gastrointestinal tract, where they develop into adult worms. However, some larvae are trapped in the lung parenchyma inciting an inflammatory response that causes persistent pulmonary tissue damage long after the resolution of infection, which returns to tissue homeostasis. However, the mechanism by which chronic lung disease develops and resolves remains unknown. Here, using immunohistochemistry, we demonstrate that small fragments and larval antigens of Ascaris suum are deposited and retained chronically in the lung parenchyma of mice following a single Ascaris infection. Our results reveal that the prolonged presence of Ascaris larval antigens in the lung parenchyma contributes to the persistent immune stimulation inducing histopathological changes observed chronically following infection, and clearly demonstrate that larval antigens are related to all phases of tissue adaptation after infection: lung injury, chronic inflammation, resolution, and tissue remodeling, in parallel to increased specific humoral immunity and the recovery of lung function in mice. Additional insight is needed into the mechanisms of Ascaris antigen to induce chronic immune responses and resolution in the host lungs following larval migration., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ricardo Toshio Fujiwara reports financial support was provided by Fundação de Amparo a Pesquisa do Estado de Minas Gerais. Ricardo Toshio Fujiwara reports financial support was provided by Conselho Nacional de Desenvolvimento Científico e Tecnológico. Nothing to declare., (Published by Elsevier Ltd.)

Control of human ascariasis, the most prevalent neglected tropical disease globally affecting 450 million people, mostly relies on mass drug administration of anthelmintics. However, chemotherapy alone is not efficient due to the high re-infection rate for people who live in the endemic area. The development of a vaccine that reduces the intensity of infection and maintains lower morbidity should be the primary target for infection control. Previously, our group demonstrated that immunization with crude Ascaris antigens in mice induced an IgG-mediated protective response with significant worm reduction. Here, we aimed to develop a multipeptide chimera vaccine based on conserved B-cell epitopes predicted from 17 common helminth proteomes using a bioinformatics algorithm. More than 480 B-cell epitopes were identified that are conserved in all 17 helminths. The Ascaris -specific epitopes were selected based on their reactivity to the pooled sera of mice immunized with Ascaris crude antigens or infected three times with A. suum infective eggs. The top 35 peptides with the strongest reactivity to Ascaris immune serum were selected to construct a chimeric antigen connected in sequence based on conformation. This chimera, called ASCVac-1, was produced as a soluble recombinant protein in an Escherichia coli expression system and, formulated with MPLA, was used to immunize mice. Mice immunized with ASCVac-1/MPLA showed around 50% reduced larvae production in the lungs after being challenged with A. suum infective eggs, along with significantly reduced inflammation and lung tissue/function damage. The reduced parasite count and pathology in infected lungs were associated with strong Th2 immune responses characterized by the high titers of antigen-specific IgG and its subclasses (IgG1, IgG2a, and IgG3) in the sera and significantly increased IL-4, IL-5, IL-13 levels in lung tissues. The reduced IL-33 titers and stimulated eosinophils were also observed in lung tissues and may also contribute to the ASCVac-1-induced protection. Taken together, the preclinical trial with ASCVac-1 chimera in a mouse model demonstrated its significant vaccine efficacy associated with strong IgG-based Th2 responses, without IgE induction, thus reducing the risk of an allergic response. All results suggest that the multiepitope-based ASCVac-1 chimera is a promising vaccine candidate against Ascaris sp. infections., Competing Interests: AG-G and RF are inventors in a patent related to the chimeric protein against Ascaris sp. infection (Brazilian INPI Protocol #BR10 20200269682). The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Gazzinelli-Guimarães, Nogueira, Amorim, Oliveira, Coqueiro-Dos-Santos, Carvalho, Kraemer, Barbosa, Fraga, Santos, de Castro, Russo, Akamatsu, Ho, Bottazzi, Hotez, Zhan, Bartholomeu, Bueno and Fujiwara.)

Ascariasis is one of the most common infections in the world and associated with significant global morbidity. Ascaris larval migration through the host's lungs is essential for larval development but leads to an exaggerated type-2 host immune response manifesting clinically as acute allergic airway disease. However, whether Ascaris larval migration can subsequently lead to chronic lung diseases remains unknown. Here, we demonstrate that a single episode of Ascaris larval migration through the host lungs induces a chronic pulmonary syndrome of type-2 inflammatory pathology and emphysema accompanied by pulmonary hemorrhage and chronic anemia in a mouse model. Our results reveal that a single episode of Ascaris larval migration through the host lungs leads to permanent lung damage with systemic effects. Remote episodes of ascariasis may drive non-communicable lung diseases such as asthma, chronic obstructive pulmonary disease (COPD), and chronic anemia in parasite endemic regions., Competing Interests: The authors have declared that no competing interests exist.

Background: Ascariasis and malaria are highly prevalent parasitic diseases in tropical regions and often have overlapping endemic areas, contributing to high morbidity and mortality rates in areas with poor sanitary conditions. Several studies have previously aimed to correlate the effects of Ascaris-Plasmodium coinfections but have obtained contradictory and inconclusive results. Therefore, the present study aimed to investigate parasitological and immunopathological aspects of the lung during murine experimental concomitant coinfection by Plasmodium berghei and Ascaris suum during larvae ascariasis., Methods: C57BL/6J mice were inoculated with 1 × 10 4 P. berghei strain NK65-NY-infected red blood cells (iRBCs) intraperitoneally and/or 2500 embryonated eggs of A. suum by oral gavage. P. berghei parasitaemia, morbidity and the survival rate were assessed. On the seventh day postinfection (dpi), A. suum lung burden analysis; bronchoalveolar lavage (BAL); histopathology; NAG, MPO and EPO activity measurements; haematological analysis; and respiratory mechanics analysis were performed. The concentrations of interleukin (IL)-1β, IL-12/IL-23p40, IL-6, IL-4, IL-33, IL-13, IL-5, IL-10, IL-17A, IFN-γ, TNF and TGF-β were assayed by sandwich ELISA., Results: Animals coinfected with P. berghei and A. suum show decreased production of type 1, 2, and 17 and regulatory cytokines; low leukocyte recruitment in the tissue; increased cellularity in the circulation; and low levels of NAG, MPO and EPO activity that lead to an increase in larvae migration, as shown by the decrease in larvae recovered in the lung parenchyma and increase in larvae recovered in the airway. This situation leads to severe airway haemorrhage and, consequently, an impairment respiratory function that leads to high morbidity and early mortality., Conclusions: This study demonstrates that the Ascaris-Plasmodium interaction is harmful to the host and suggests that this coinfection may potentiate Ascaris-associated pathology by dampening the Ascaris-specific immune response, resulting in the early death of affected animals.

Ascariasis is considered the most neglected tropical disease, and is a major problem for the public health system. However, idiopathic pulmonary fibrosis (IPF) is a result of chronic extracellular deposition of matrix in the pulmonary parenchyma, and thickening of the alveolar septa, which reduces alveolar gas exchange. Considering the high rates of ascariasis and pulmonary fibrosis, we believe that these two diseases may co-exist and possibly lead to comorbidities. We therefore investigated the mechanisms involved in comorbidity of Ascaris suum (A. suum) infection, which could interfere with the progression of pulmonary fibrosis. In addition, we evaluated whether a previous lung fibrosis could interfere with the pulmonary cycle of A. suum in mice. The most important findings related to comorbidity in which A. suum infection exacerbated pulmonary and liver injury, inflammation and dysfunction, but did not promote excessive fibrosis in mice during the investigated comorbidity period. Interestingly, we found that pulmonary fibrosis did not alter the parasite cycle that transmigrated preferentially through preserved but not fibrotic areas of the lungs. Collectively, our results demonstrate that A. suum infection leads to comorbidity, and contributes to the aggravation of pulmonary dysfunction during pulmonary fibrosis, which also leads to significant liver injury and inflammation, without changing the A. suum cycle in the lungs., Competing Interests: The authors have declared that no competing interests exist.

Ascaris suum is a helminth parasite of pigs closely related to its human counterpart, A. lumbricoides, which infects almost 1 billion people. Ascaris is thought to modulate host immune and inflammatory responses, which may drive immune hyporesponsiveness during chronic infections. Using transcriptomic analysis, we show here that pigs with a chronic A. suum infection have a substantial suppression of inflammatory pathways in the intestinal mucosa, with a broad downregulation of genes encoding cytokines and antigen-processing and costimulatory molecules. A. suum body fluid (ABF) suppressed similar transcriptional pathways in human dendritic cells (DCs) in vitro. DCs exposed to ABF secreted minimal amounts of cytokines and had impaired production of cyclooxygengase-2, altered glucose metabolism, and reduced capacity to induce interferon-gamma production in T cells. Our in vivo and in vitro data provide an insight into mucosal immune modulation during Ascaris infection, and show that A. suum profoundly suppresses immune and inflammatory pathways., (© The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Ascaris lumbricoides or roundworms' propensity to produce large number of eggs that are resistant to extremes of environmental conditions have made them one of the highly prevalent and geographically well distributed nematodes among poor socio-economic regions throughout the world. We present an unusual case of fatal gastro-intestinal ascariasis where general neglect, and firm and prolonged reliance on traditional healing methods led to aggregation of roundworms to such an extent that otherwise seems improbable in modern times and, hence, is worth reporting., (© The Author(s) 2015.)

We receive around 60 cases of hepatic abscess in a year. The commonest diagnosis reached at the time of discharge is amoebic liver abscess. The diagnosis of amoebic liver abscess is mostly presumptive and thus the patients are usually given a mixed treatment with injection ceftriaxone and tablet metronidazole. Here we report three cases of hepatic abscess diagnosed recently, where ascariasis was the probable etiology. Ascariasis may be a much commoner cause of hepatic abscesses in this region than we think.

A 10-year-old child presented with dull aching periumbilical abdominal pain for 15 days. The child was not gaining weight despite a good appetite. Physical examination of the child revealed grade-I protein energy malnourishment (PEM) according to IAP (Indian Academic of Paediatrics) classification. The rest of the systemic examination was normal. Routine blood investigation revealed anaemia with eosinophilia. Abdominal ultrasonography did not show any abnormality with curvilinear transducer (3.5-5 MHz), however, linear ultrasound transducer (7.5-12 MHz) with harmonic tissue imaging showed worms in the lumen of the small intestine with curling movement on real time scanning. Stool examination for the eggs of ascariasis was positive. The patient was treated with antihelminthic drugs. Dietary modification for the PEM was advised. After 3 months of treatment, the patient improved and stool examination for Ascaris was negative on follow-up., (2015 BMJ Publishing Group Ltd.)

Introduction: Ultrasonographic demonstration of intra biliary parallel lines or "inner tube sign" is considered diagnostic for biliary ascariasis in regions where ascariasis is endemic., Patients & Methods: 148 patients with inner tube sign on ultrasonography were evaluated. In most, diagnosis was confirmed by ultrasonographic demonstration of restitution of normal appearance of bile duct with passage of round worms in vomitus or faeces., Results: Diagnosis was confirmed in 122 of 148 patients. 26 patients were lost to follow-up. Biliary ascariasis was responsible for the sign "parallel lines" in 113 patients. Of the remaining, intrabiliary stents were responsible for the "inner tube sign" in six whereas in three it was due to hydatid membranes following intrabiliary rupture of hydatid cyst., Conclusion: Biliary ascariasis is the commonest cause of inner tube sign in the tropics. However, this sign can also be produced by biliary stents and hydatid membranes. Awareness of these possibilities is essential for sonologists in the tropics.

Background: Ascariasis is a worldwide health problem. Patients usually get treated with antihelminthics. Rarely, undiagnosed cases can present with surgical complications., Aim: To study the clinico-pathological characteristics of small bowel specimens of patients presenting with surgical complications of ascariasis., Methods: This is a retrospective analysis of small bowel specimens of patients presenting with surgical complications of ascariasis from a period of 2010 to 2012, received in our department., Results: The patients were of all age groups and mainly presented with intestinal obstruction and perforation. Transmural gangrenous change was seen in all nine cases. Encysted ova were seen in five cases. Two of the cases showed partial to complete infarction of isolated mesenteric lymph nodes., Conclusion: Ascariasis may cause transmural gangrene of bowel as well as mesenteric lymph node infarction.

Studies related to the immunobiological aspects of an Ascaris spp. infection are still scarce, especially those that aim to elucidate the early events of the immune response. In this study, we demonstrated a novel standardized method for early experimental Ascaris infection, providing additional information about the infectivity of eggs embryonated in vitro as well as the influence of host age on development of the infection. Finally, we characterised the immunopathology of early infection, focusing on the tissue and systemic cytokine profiles and the histopathology of infection in the lungs of BALB/c mice. Our results demonstrated that the highest egg infectivity occurred on the 100th and 200th days of in vitro embryonation and that 8 week-old BALB/c mice were more susceptible to infection than 16 week-old mice. Ascaris-infected mice showed an early, significant level of IL-5 production in the lungs 4 days p.i., followed by an increase in the level of neutrophils in the inflammatory infiltrate at 8 days p.i, which was correlated with the peak of larval migration in the tissue and a significant level of IL-6 production. The inflammatory infiltrate in the lungs was gradually replaced by mononuclear cells and eosinophils on the 10th and 12th days p.i., respectively, and an increase in TNF levels was observed. The downmodulation of systemic TCD4(+) cell numbers might suggest that T cell hyporesponsiveness was induced by the Ascaris spp. larvae, contributing to safeguarding parasite survival during larval migration. Taken together, the novel aspects of Ascaris infection presented here enabled a better understanding of the immunopathological events during larval migration, providing insight for further studies focused on immunisation and immunoprophylatic assays., (Copyright © 2013 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.)

Background: Co-infection with malaria and intestinal parasites such as Ascaris lumbricoides is common. Malaria parasites induce a pro-inflammatory immune response that contributes to the pathogenic sequelae, such as malarial anaemia, that occur in malaria infection. Ascaris is known to create an anti-inflammatory immune environment which could, in theory, counteract the anti-malarial inflammatory immune response, minimizing the severity of malarial anaemia. This study examined whether Ascaris co-infection can minimize the severity of malarial anaemia., Methods: Data from a randomized controlled trial on the effect of antihelminthic treatment in Nigerian preschool-aged (6-59 months) children conducted in 2006-2007 were analysed to examine the effect of malaria and Ascaris co-infection on anaemia severity. Children were enrolled and tested for malaria, helminths and anaemia at baseline, four, and eight months. Six hundred and ninety subjects were analysed in this study. Generalized linear mixed models were used to assess the relationship between infection status and Ascaris and Plasmodium parasite intensity on severity of anaemia, defined as a haemoglobin less than 11 g/dL., Results: Malaria prevalence ranged from 35-78% over the course of this study. Of the malaria-infected children, 55% were co-infected with Ascaris at baseline, 60% were co-infected four months later and 48% were co-infected eight months later, underlining the persistent prevalence of malaria-nematode co-infections in this population. Over the course of the study the percentage of anaemic subjects in the population ranged between 84% at baseline and 77% at the eight-month time point. The odds of being anaemic were four to five times higher in children infected with malaria compared to those without malaria. Ascaris infection alone did not increase the odds of being anaemic, indicating that malaria was the main cause of anaemia in this population. There was no significant difference in the severity of anaemia between children singly infected with malaria and co-infected with malaria and Ascaris., Conclusion: In this cohort of Nigerian preschool children, malaria infection was the major contributor to anaemia status. Ascaris co-infection neither exacerbated nor ameliorated the severity of malarial anaemia.

Ascaris lumbricoides is the largest intestinal nematode parasite of man, which can lead to various complications because of its mobility. As the esophagus is not normal habitat of Ascaris, the report of esophageal ascariasis is rare. An old female presented with dysphagia after an intake of several red bean buns and haw jellies. The barium meal examination revealed a spherical defect in the lower esophagus. Esophageal bezoar or esophageal carcinoma was considered at the beginning. The patient fasted, and received fluid replacement treatment as well as some oral drugs such as proton pump inhibitor and sodium bicarbonate. Then upper gastrointestinal endoscopy was done to further confirm the diagnosis and found a live Ascaris lumbricoides in the gastric antrum and two in the duodenal bulb. The conclusive diagnosis was ascariasis. The esophageal space-occupying lesion might be the entangled worm bolus. Anthelmitnic treatment with mebendazole improved patient's clinical manifestations along with normalization of the radiological findings during a 2-wk follow-up. Authors report herein this rare case of Ascaris lumbricoides in the esophagus, emphasizing the importance of awareness of this parasitic infection as it often presents with different and unspecific symptoms.

Ascaris suum is the most important internal parasite in farmed pigs world-wide. In England, the BPEX Pig Health Scheme (BPHS) monitors the prevalence of ascariosis in slaughtered finished pigs by identifying milk spots - the healing lesions caused by A. suum larvae migration through the liver. This study investigates the trend of milk spot lesions from July 2005 to December 2010 to identify the progress made by the industry in controlling this parasitic disease. For visual explorations, the monthly prevalence for milk spots was modelled using "STL", a seasonal-trend decomposition method based on locally weighted regression. Random effects binomial modelling accounting for clustering at batch level was used to test the significance of the trend and seasonality. Additionally, the differences in the milk spot prevalence trends for BPHS members (those that joined the scheme) and non-members were investigated and tested. A mean of 12,442 pigs was assessed per month (in 290 batches) across 12 pig abattoirs over the study period, from which a monthly mean of 7102 pigs (159 batches) came from BPHS members. A mild overall decrease in prevalence of milk spots over the monitored period was identified as well as a seasonal variation which showed peaks in summer and at the beginning of autumn. BPHS members maintained a lower prevalence than non-members. The results from this work illustrate ascariosis as a persistent problem in current farm production., (© 2011 Elsevier B.V. All rights reserved.)

Ascaris Lumbricoides is the most common worm found in human beings and it is the largest of the intestinal nematodes parasitizing humanity. The most common complication of Ascariasis is mechanical bowel obstruction caused by a large number of worms. Bowel obstruction can also be caused by various toxins released by the worms. A large worm bolus can also cause volvulus or intussusception. We report a case of Intestinal Obstruction due to an Ileal MZBCL in an Ascaris. Lumbricoides infestation setting.

Ascaris infestation in the gastrointestinal tract is well known in Asian countries. It can be asymptomatic or can present with symptoms of acute abdomen. Perforation and torsion with gangrene are its very rare fatal complications but an important cause of mortality in children. Although ascariasis is very rare in developed countries, clinicians should consider this potentially dangerous, yet treatable, infection in the differential diagnosis of acute abdomen. We herein report a series of five cases of intestinal gangrene secondary to extensive infestation by Ascaris lumbricoides in children aged 1-4 years., ((c) 2009 Elsevier GmbH. All rights reserved.)

Ascariasis is the most common helminthic infection in developing countries. It may cause chronic abdominal pain, tenderness and bloating. Our aim is to report a case of acute episodic abdominal pain and pancreatitis associated with ascariasis. We report a 59-year-old female patient who was admitted for acute abdominal pain, having had several previous similar events before one of them was diagnosed as acute idiopathic pancreatitis. On admission, her physical exam was normal. Laboratory results showed hemoglobin 12.2 g/dL, white blood cell count 11 900 cells/mm(3), eosinophils 420 cells/mm(3), serum amylase 84 IU/mL, lipase 22 IU/mL and normal liver function tests. Abdominal ultrasound and a plain abdominal X-ray were also normal. An upper endoscopy showed round white worms in the duodenum and the stomach, some of them with bile in their intestines. The intestinal parasites were diagnosed as Ascaris lumbricoides, and the patient was started on albendazole, with full recovery within a week. We believe that ascariasis should be considered in patients with recurrent abdominal pain and idiopathic pancreatitis.

The generative mechanism(s) of aggregation and predisposition to Ascaris lumbricoides and A. suum infections in their host population are currently unknown and difficult to elucidate in humans and pigs for ethical/logistical reasons. A recently developed, optimized murine model based on 2 inbred strains, putatively susceptible (C57BL/6j) and resistant (CBA/Ca) to infection, was exploited to elucidate further the basis of the contrasting parasite burdens, most evident at the pulmonary stage. We explored the kinetics of early infection, focusing on the composite lobes of the liver and lung, over the first 8 days in an effort to achieve a more detailed understanding of the larval dispersal over time and the point at which worm burdens diverge. Larval recoveries showed a heterogenous distribution among the lobes of the lungs, being higher in the right lung of both strains, and in the susceptible strain larvae accumulating preferentially in 2 (caudal and middle) of the 4 lobes. Total larval burdens in these 2 lobes were largely responsible for the higher worm burdens in the susceptible strain. While total lung larval recoveries significantly differed between mouse strains, a difference in liver larval burdens was not observed. However, an earlier intense inflammatory response coupled with more rapid tissue repair in the hepatic lobes was observed in CBA/Ca mice, in contrast to C57BL/6j mice, and it is possible that these processes are responsible for restricting onward pulmonary larval migration in the resistant genotype.

Erythema nodosum belongs to a group of relatively common hypodermal inflammations. It occurs mainly among women, particularly young women. The etiology of the disease is not clear. Most frequently, changes appear on the surface of the frontal part of the shins. Initially, red nodules change in color to dark brown and then to yellow and green. There is neither dissolution nor cicatrization of the exanthema. Regression is frequent. We present a case of erythema nodosum caused by Ascaris lumbricoides infection as well as by an early Chlamydophila pneumoniae infection, whose etiology has rarely been described in the literature. We were not able to confirm which factor was responsible for the occurrence of the skin changes as treatment of both infections was effective and all skin changes later disappeared completely. Particular attention should be paid to the fact that precise diagnosis of a patient and the search for etiologic factors, even rare ones, are crucial to obtain good results with treatment of erythema nodosum.

Pigs infected with Ascaris suum or controls were given 100 microg (low-dose) or 1,000 microg (high-dose) all-trans retinoic acid (ATRA)/kg body weight in corn oil or corn oil alone per os on days after inoculation (DAI) -1, +1, and +3 with infective eggs. Treatment with ATRA increased interleukin 4 (IL4) and IL12p70 in plasma of infected pigs at 7 DAI and augmented bronchoalveolar lavage (BAL) eosinophilia observed at 7 and 14 DAI. To explore potential molecular mechanisms underlying these observations, a quantitative real-time reverse transcription (RT)-PCR array was used to examine mRNA expression in tissue. Ascaris-infected pigs had increased levels of liver mRNA for T-helper-2 (Th2)-associated cytokines, mast cell markers, and T regulatory (Treg) cells, while infected pigs given ATRA had higher IL4, IL13, CCL11, CCL26, CCL17, CCL22, and TPSB1 expression. Gene expression for Th1-associated markers (IFNG, IL12B, and TBX21), the CXCR3 ligand (CXCL9), IL1B, and the putative Treg marker TNFRSF18 was also increased. Expression of IL4, IL13, IL1B, IL6, CCL11, and CCL26 was increased in the lungs of infected pigs treated with ATRA. To determine a putative cellular source of eosinophil chemoattractants, alveolar macrophages were treated with IL4 and/or ATRA in vitro. IL4 induced CCL11, CCL17, CCL22, and CCL26 mRNA, and ATRA increased the basal and IL4-stimulated expression of CCL17 and CCL22. Thus, ATRA augments a diverse Th1-, Th2-, Treg-, and inflammation-associated response in swine infected with A. suum, and the increased BAL eosinophilia may be related to enhanced induction of eosinophil chemokine activity by alveolar macrophages.

Ascaris lumbricoides and Ascaris suum are important helminth parasites of humans and pigs, respectively. Although it is now well established that the presence of mature adult worms in the host intestine contributes to significant nutritional morbidity, the impact of larval migratory ascariasis is far less well understood. The development of a mouse model to explore susceptibility and resistance to larval ascariasis in the lungs provided an opportunity to observe the impact of larval migration on host growth during the course of infection. Changes in body weight were monitored in two strains of inbred mice, the susceptible C57BL/6j and the resistant CBA/Ca. Groups of mice received one of four doses: 100, 500, 1000 and 3000 fully embryonated A. suum ova. Infected mice underwent post-mortem on days 6, 7 and 8 post-infection. Control mice received a placebo dose of intubation medium and underwent post-mortem on day 7 post-infection. Mice were weighed pre-infection (day 0) and post-infection on the day of post-mortem. At post-mortem, the lungs of each mouse were removed for enumeration of Ascaris larval burdens by means of the modified Baermann method. Control mice of each strain showed an increase in weight from pre-infection to post-infection day. Within the C57BL/6j strain, mice infected with higher doses of Ascaris eggs experienced a reduction in body weight; for those given 3000 eggs this was on all three post-mortem days, and for those given 1000, on days 7 and 8. For CBA/Ca mice, only mice receiving the 3000 dose demonstrated a reduction in body weight. These findings suggest that larval migratory ascariasis has a significant negative impact upon host growth and that this is related to infective dose and larval burden.

Summary: The genotypes of both host and parasite may influence the outcome of parasitic infections, but few attempts have been made to quantify the effect of parasite genotype on macroparasite infections of socio-economic importance. We examined variation in particular traits during the infection in pigs with the parasitic nematode Ascaris suum. We infected 26 pigs with mixtures of equal proportions of embryonated eggs from 4 single female worms each with a unique mtDNA haplotype--the eggs from each female worm were a mixture of siblings and half-siblings. Pigs were necropsied on days 14, 17 and 28 following inoculation, which corresponded to time-points before, during and after the main immune responses against the nematode. A total of approximately 11,000 worms were recovered at necropsy. The location in the small intestine was recorded for all worms and the length and mtDNA haplotype were determined for about 4200 individual worms. There were significant differences in the distribution and abundance of the 4 individual haplotypes among individual pigs demonstrating strong interactions between parasite and host. We found significant differences in the abundance and position in the small intestine as well as the size of worms among haplotypes. We conclude that both parasite and host effects as well as the interplay between them play important roles in determining the characteristics and outcome of infection.

This report present first case of Ascaridia numidae isolated from three dead rock partridges (Alectoris chukar) with stressing morphological characteristics and its responsiveness to the medical treatment. A. numidae was confirmed by presence of one papilla on the posterior region of the preanal sucker and a total of 10 pairs of the caudal papillae. In necropsy, a total of 680 (282 male and 3,988 female) A. numidae and 289 (147 male and 142 female) Heterakis dispar were isolated from all partridges. Females were 11.20 mm longer and 0.22 mm wider than males. There was no difference in length of oesophagus (2.27 mm). Lengths of the spikules were equals and ranged from 2.08 to 2.93 according to the body size. Vulva was located in medial line and the mean egg size was 0.10 x 0.06 mm. Faecal samples from live birds from the same farm contained Ascaridia spp. and Heterakis spp. eggs. No eggs were encountered 1 week after oral administration of a single dose of levamisole (30 mg/kg), but 3 months post-medication. In conclusion, this is the first case reporting A. numidae in exotic birds in Turkey. A. numidae has unique papillae that are distinguishable from the other ascarids and is responsive to medical treatment as long as hygienic conditions are maintained.

Background: Vesicovaginal fistulae are well-recognized complications of radiotherapy for the treatment of cervical cancer. These patients often require some form of urinary diversion. Small bowel is often utilized for these purposes., Case: A patient with stage IIB cervical cancer presented with a vesicovaginal fistula 6 years post-radiotherapy. An ileal conduit was performed. On day 9 post-surgery breakdown of the small bowel anastomosis was suspected. At laparotomy small bowel anastomotic breakdown was confirmed with round worms at the anastomotic site., Conclusion: Perforation of small bowel by round worm has been previously described in a patient with Meckel' s diverticulum. This report describes an unusual cause of small bowel anastomotic breakdown following urinary diversion.

Ascariasis is an important infection in humans (Ascaris lumbricoides) and pigs (Ascaris suum) and individuals appear to be predisposed to either heavy or light worm burdens. These extremes of susceptibility and resistance are represented in a mouse model by 2 strains of mice, CBA mice showing high resistance to infection and C57BL/6 which are highly susceptible, as reflected in worm burdens in the lungs 6-7 days after infection. In an attempt to identify the point at which the difference between these 2 strains is first manifested, we quantified worm burdens at key stages during infection leading up to the pulmonary stage of development. Thus mice were inoculated with fully embryonated A. suum eggs and larval burdens were enumerated in the large intestine and rectum, liver and lungs of the 2 strains at 6 h post-inoculation (p.i.) and on each of days 1-8 p.i. inclusively. A higher percentage of the total inoculum was recovered from the intestine/rectum of C57BL/6j mice in contrast to CBA/Ca mice at 6 h p.i. Larvae were recovered from the intestinal contents and also whilst actively migrating through the large intestinal wall. The number of larvae recovered was significantly reduced in CBA/Ca mice in contrast to C57BL/6j mice between the phase of migration from the liver and arrival in the lungs. The combined results of the inoculation of mice with corticosteroids and the examination of the change in profile and number of leukocytes present in bronchoalveolar lavage fluid suggested that the pulmonary inflammatory immune response was not prominently involved in primary protection of mice to A. suum infection in the latter days of infection in the lungs. The susceptible C57BL/6j mice produced a BAL response almost twice as intense as that of resistant CBA/Ca mice with stronger neutrophil, lymphocyte and eosinophil but not macrophage components, suggesting that the difference in worm burdens between the strains was generated earlier in the course of infection. These results were further corroborated by a histological examination of the lung tissues which showed that the passage of the larval stages of A. suum through the mouse lungs was associated with a marked inflammatory response in both strains. Again, C57BL/6j mice exhibited increased inflammation relative to CBA/Ca mice. Hence some hepatic/post-hepatic factor that varies between the 2 strains, but exerts its effect before the lung phase plays a critical role in determining the success of larvae through the host tissues. The possible sites of this host defence are reviewed.

Although the etiology of eosinophilic cholecystitis is still obscure, the postulated causes include allergies, parasites, hypereosinophilic syndrome, and eosinophilic gastroenteritis. It is sometimes accompanied by several complications, but a simultaneous onset with pericarditis is very rare. A 28-year-old woman complained of acute right hypocondrial pain and dyspnea associated with systemic eruption. Several imaging modalities revealed acute cholecystitis and pericarditis with massive pericardial effusion. A marked peripheral blood eosinophilia was observed, and the eruption was diagnosed as urticaria. Her serum had a high titer of antibody against Ascaris lumbricoides. Treatment with albendazole drastically improved all clinical manifestations along with normalization of the imaging features and eosinophilia. We report herein a rare case of simultaneous onset of acute cholecystitis and pericarditis associated with a marked eosinophilia caused by parasitic infection.

Pigs single inoculated with Ascaris suum eggs expel the majority of larvae between days 14 and 21 post inoculation (p.i.), but the role of the immune system in expulsion is unclear. To investigate the dynamics of immune responses before, during and after the expulsion of A. suum larvae, pigs inoculated with 10 000 A. suum eggs were sequentially necropsied. Ascaris suum gradually moved distally from days 10-14 p.i. and only a few larvae were left by day 21 p.i. Pronounced increases in mucosal A. suum-specific IgA antibody secreting cells (ASCs) were already found by day 10 p.i. especially in the proximal jejunum, while only small increases in parasite-specific IgM ASCs were observed by day 21 p.i. in both proximal and distal jejunum. No mucosal IgG ASC responses could be detected. Increases in systemic A. suum-specific IgG1, IgM and to a lesser extent IgA antibodies were observed, while IgG2 remained almost unchanged. The levels of eosinophils and mast cells in the small intestinal mucosa did not change throughout infection. The results demonstrate that both systemic and mucosal A. suum-specific effector mechanisms are strongly stimulated in A. suum single infections and indicate that mucosal IgA may be an important mediator in the expulsion of A. suum.

Objective: Numbers of mast cells (MCs) of different subpopulations and the extent of eosinophil infiltration were compared in Crohn's disease and ascariasis. These two types of intestinal inflammation are complementary with regard to T cell response (TH1 versus TH2), prevalence and environmental factors., Methods: Histochemical, immunohistochemical and ultrastructural tools were applied to biopsies of morphologically uninvolved colon, ileum and duodenum from Crohn's and ascariasis patients, as well as resection margins and tissues from an experimental porcine ascariasis model. MC subsets were defined by their dye-binding properties, and their chymase content was analysed using biochemical tools., Results: The TH2 (IgE-mediated) response in ascariasis was characterised by a dramatic increase in mucosal- type MCs (MMCs) and eosinophils in both the mucosa and the deeper layers of the intestinal wall and a simultaneous decrease of connective tissue-type MCs (CTMCs). Uninvolved intestine of Crohn's patients showed moderate proliferation of CTMCs in the deeper layers of the intestinal wall, but a significant decrease of the MMCs, associated with moderate eosinophilia in all layers of the gut. Similar changes were present in the uninvolved duodenum of Crohn's patients. Comparable amounts of chymase could be extracted from mucosal and submucosal duodenum, with similar proportions of its two principal isoforms in each., Conclusions: Our results indicate that T cell responses (TH1 or TH2) are associated with different MC subsets in intestinal inflammation. Changes remote from the focus of inflammation point to the systemic nature of the different MC responses., (Copyright 2003 S. Karger AG, Basel)

From June 1985 to June 1999, 120 patients were diagnosed by means of panendoscopy, choledocoscopy, and endoscopic retrograde cholangiopancreatography as having biliary and pancreatic ascariasis. All duodenoscopic procedures were performed under fluoroscopic control. Endoscopic extraction was successful in 99 of 108 (92%) patients, some of whom had had previous endoscopic sphincterotomy. The endoscopic accessories used were a basket catheter, polypectomy snare, and balloon catheter. Because no significant complications were observed after this endoscopic treatment, we recommend endoscopic extractions for biliary ascariasis.

This paper describes the histopathological features and the cellular distribution of T lymphocytes (CD3), B cells (CD79a), immunoglobulin (IgG, IgA, IgM)-bearing plasma cells, macrophages (Mac387 and alpha-1-antitrypsin), MHC class II antigen and S-100 protein in hepatic white spots associated with naturally occurring Ascaris suum parasitism in 35 pigs. Hepatic granulomas were observed in 10 pigs, whereas lymphoid proliferation with a diffuse or lymphonodular pattern was the main histopathological lesion in 14 other pigs, and portal fibrosis in a further 11 animals. In lymphonodular lesions, the distribution of immunoreactive cells with all antibodies tested was closely similar to that found in the cortex of lymph nodes. Thus, lymphoid follicles were composed mainly of CD79a(+)B cells and interfollicular tissue was composed mainly of CD3(+)T lymphocytes. The presence of follicular dendritic and interdigitating cells expressing S-100 protein and MHC class II antigen in lymphonodular lesions suggested that these are highly organized structures developed to enhance antigen presentation to B and T cells, and consequently the local immune response against the parasite. The humoral local response was represented mainly by IgG-secreting plasma cells., (Copyright Harcourt Publishers Ltd.)

An experimental infection with Ascaris of pig origin showed that Ascaris suum larvae can migrate extra-intestinally in chickens. Furthermore, after feeding piglets with Ascaris infected chicken liver and lungs, it was possible to recover larvae from their lungs. These observations suggest that the chicken could serve as a paratenic host for Ascaris. There is also the possibility for zoonotic transmission if raw chicken livers are consumed by humans.

Following reports of increased IgE in severe malaria and hypothesizing that helminth coinfections could modify its outcome, we conducted a retrospective case-control study to establish whether helminths affect the evolution of Plasmodium falciparum malaria. Some 182 severe cases, 315 mild controls and 40 controls with circulating schizonts were examined for intestinal helminths. Comparing cerebral malaria with mild controls, Ascaris lumbricoides was associated with a protective adjusted odds ratio (OR) of 0.58 (0. 32-1.03) P = 0.06, for coinfection with Ascaris and Necator americanus, OR = 0.39 (0.17-0.88) P = 0.02. Protection followed a dose-effect trend (P = 0.008). When comparing cerebral malaria cases and controls with circulating schizonts the OR was 0.25 (0.009-0.67) P = 0.006. We hypothesized that Ascaris infected patients may have had decreased cyto-adherence, possibly through endothelial cell receptor downregulation and/or decreased splenic clearance leading to the absence of selection of virulent P. falciparum strains. IgE-anti-IgE immune complexes resulting from helminth preinfection may have an important role in influencing clinical presentation of severe malaria, and in establishing malaria tolerance, through the CD23/NO pathway.

A 13-month-old boy developed eosinophilic meningoencephalitis, retinitis, and a protracted encephalopathy with severe residual deficits. The initial MR examination revealed diffuse periventricular white matter disease, and follow-up images showed atrophy. Brain biopsy, serology, and epidemiologic studies lead to the diagnosis of Baylisascaris procyonis infection, a parasitic disease contracted through exposure to soil contaminated by the eggs of a common raccoon intestinal roundworm. The pathologic, epidemiologic, and imaging features of this disease are herein reviewed.

The normal tissue migration of Ascaris suum in the pig host involves larval development in the liver accompanied by considerable pathological changes. The vast majority of larvae that reach the small intestine are later expelled by unknown mechanisms. We show that when migration through the liver is bypassed by inoculation of pigs with an intravenous dose of larvae hatched in vitro, the larvae not only complete migration and return to the small intestine, but they also seem to have a greater chance of survival to adulthood. This technique offers new possibilities for studies on specific lung involvement in protective immunity, provides valuable information for the understanding of self cure by larval expulsion, and adds to our understanding of the evolution of migration of Ascaris larvae in tissues.

Little is known about preexisting lesions in livers of children with pyogenic liver abscess (PLA). Study of these lesions may elucidate possible predisposing factors for the disease. In Vitória, state of Espirito Santo, Brazil, PLA in children is frequently associated with helminthic infections and eosinophilia. We hypothesize that nematode infection with larvae migrating through the liver is a predisposing factor for PLA, because the infection induces immunomodulation and likely trapping of bacteria in liver granulomas. In this report, we describe observations of 22 cases of PLA in children studied at autopsy (16 cases) or in surgical biopsies (6 cases), including 17 boys and 5 girls ranging in age from 1 to 13 years (mean 4.6 years, median 3.5 years). Multiple abscesses in both lobes were found in 13 cases and a single abscess was found in the right lobe in 10 cases. All cases showed histologically classical pyogenic inflammation without morphological evidence of amoebiasis. In six cases there were granulomas similar to those caused by larva migrans visceralis (from Toxocara or other nematodes) in liver tissue not affected by the abscess. Nematode antigens in central areas of necrosis of granuloma in all six cases and fragments of a larva, possibly of Toxocara, were found on samples immunohistochemically stained with polyclonal anti-Toxocara antibodies. There were numerous eosinophils in abscesses with Charcot-Leyden crystals. Eosinophils were found frequently in portal triads far from the abscess wall. In four cases, in which bile duct ascariasis was found, worms were noted in the bile ducts, and eggs were found in liver parenchyma surrounding the abscess in two cases. Foreign-body granulomas were found in one case in which penetrating trauma was the cause of abscess. In one case there was one histiocytic granuloma whose origin was not determined. The observation of six cases of granuloma similar to larva migrans visceralis (or produced by other nematode larva) in liver tissue not directly affected by the abscess supports the hypothesis that helminth infections with larva migrating through the liver are a predisposing factor for pyogenic hepatic abscess in children.