Proliferative Enteritis Research Articles

Porcine Lawsonia intracellularis Ileitis in Italy and Its Association with Porcine Circovirus Type 2 (PCV2) Infection.

The objective of this study was to employ a diagnostic algorithm, which involves detecting positive farms by stool PCR followed by PCR and histology/immunohistochemistry on ileum samples, for diagnosing Lawsonia intracellularis proliferative enteritis in Northern Italy. The primary aim was to examine the relationship between the gold standard of L. intracellularis diagnostics, namely histology and immunohistochemistry, and PCR in acute and chronic cases of L. intracellularis enteritides. An additional goal was to investigate the coinfection of L. intracellularis with porcine circovirus type 2 (PCV2). Twenty-eight ileum samples, including four from acute cases and 24 from chronic cases, were collected. PCR yielded positive results in 19 cases (four acute and 15 chronic cases). In comparison, immunohistochemistry was positive in 16 cases (four acute and 12 chronic cases), with an observed agreement of 89%. The findings suggest that performing the two tests in series can increase the specificity of the causal diagnosis. PCR may be used as a screening tool to identify the presence of the microorganism, and only positive cases will be examined by histology and immunohistochemistry to confirm the causative role of L. intracellularis. Co-infection with PCV2 was demonstrate in two out of four acute cases and in two out of 24 chronic cases, providing further evidence to support the hypothesis that when the infection starts with ubiquitous pathogens such as L. intracellularis, it may boost the possibility of PCV2 replication, especially in acute cases. As a result, this may trigger a transition from subclinical to clinical forms of PCV2 disease.

Goat Paratuberculosis: Experimental Model for the Evaluation of Mycobacterium Persistence in Raw Milk Cheese.

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of chronic proliferative enteritis found in ruminants, known as paratuberculosis (PTB). The spread of PTB is increasing in countries with advanced animal husbandry practices, leading to significant economic losses. Moreover, a supposed zoonotic role of MAP in Crohn’s disease (CD) in humans has been discussed by the scientific community; however, although the association between MAP and CD has generally been accepted, it is still up for debate if MAP is the main cause of CD, a contributing factor, or merely a commensal organism for the development of CD. The aim of this study was to assess the survival of MAP during the entire production process of a traditional Italian goat’s raw milk fresh cheese, the “Robiola di Roccaverano”, assessing the survival rate and persistence of MAP in the final product. A mix of MAP field isolates from goats of the Roccaverano area and a reference ATCC strain were used to carry out milk in experimental inoculation. Samples of milk, curd and cheese were taken in two consecutive batches of production. Microbiological challenge tests, evaluated by f57-qPCR, showed a significant decrease in MAP charge during the cheesemaking process for both batches, suggesting the productive process has an impact on MAP survival.

Recurrent colic in a 1‐year‐old dromedary camel

AbstractA 1‐year‐old male castrated dromedary camel presented with a 3‐week history of intermittent colic characterized by diarrhoea, inappetence and lethargy. The patient was originally diagnosed with intestinal parasites (Trichuris spp.) 2 weeks prior, for which he was dewormed and released from the hospital. However, the patient's clinical signs did not improve, so further workup was deemed necessary. Based on severe weight loss and hypoalbunaemia, with no further detection of common intestinal parasites, a suspicion of proliferative enteritis led to additional diagnostics. A faecal sample submitted for Lawsonia intracelluris PCR tested positive for the bacterium. The patient received four treatments of oxytetracycline, and clinical signs significantly improved. Another PCR was performed 4 weeks after treatment and was negative for L. intracellularis. While other causes of this camel's clinical signs are possible, this case suggests L. intracellularis may have contributed to signs of recurrent colic in a dromedary camel.

Early Detection of Mycobacterium avium subsp. paratuberculosis Infected Cattle: Use of Experimental Johnins and Innovative Interferon-Gamma Test Interpretative Criteria.

Paratuberculosis (PTB), also known as Johne's disease, is a chronic proliferative enteritis of ruminants caused by Mycobacterium avium subsp.paratuberculosis (MAP). To date, PTB diagnosis, based on serology, fecal culture, and real-time polymerase chain reaction, has identified animals in advanced stages of infection. To detect MAP infection in animals earlier, the interferon-gamma (IFN-γ) test may be applied. This assay detects cytokines produced by T-lymphocytes of infected subjects after stimulation with purified protein derivatives (PPDs), extracted from Mycobacterium bovis (MB) and from M. avium (MA). The study involved three bovine herds: one PTB-infected herd, one PTB-free herd, and one with an outbreak of bovine tuberculosis. The IFN-γ test was performed on 235 animals, using bovine PPD (PPDB), avian PPD (PPDA), and three experimental PPD Johnins (PPDJs) extracted from a synthetic liquid medium culture of MAP (PPDJ A, B, and C), to assess early MAP detection and avoid false reactions to MB. Furthermore, IFN-γ results were evaluated using 12 interpretative criteria (ICs), based on the differences and ratio between PPD optical density (OD) and IFN-γ basal OD values after lymphocytic stimulation. IC accuracy was expressed as area under the receiver operating characteristic curve. Through a longitudinal study, PPDJs proved to be specific and sensitive in the detection of MAP-infected animals. Among the evaluated ICs, six showed the best performance in terms of accuracy (p < 0.0001), highlighting PTB subclinical infections. In particular, the two best criteria reached sensitivity values of 100% [confidence interval (CI) 95%, 94.1–100%] with a specificity of 91.8% (CI 95%, 81.9–97.3%) and sensitivity levels of 80.6% (CI 95%, 69.1–89.2%) with a specificity of 100% (CI 95%, 94.1–100%). Thus, the IFN-γ assay proved to be a useful diagnostic tool to identify early subclinical MAP-infected animals, in order to manage infected cattle or those exposed to MAP and to monitor younger calves within a herd. Furthermore, the IFN-γ test can be considered an additional test to avoid the introduction of MAP-infected animals, especially in herds where disease has already been eradicated and preservation of the health status is required to maintain the PTB certification level.

A real-time loop-mediated isothermal amplification method for rapid detection of Lawsonia intracellularis in porcine fecal samples

Porcine proliferative enteritis is a common diarrheal disease characterized by thickening of the intestinal mucosa in swine due to enterocyte proliferation, which is caused by Lawsonia intracellularis. In this study, a real-time loop-mediated isothermal amplification (LAMP) assay was developed to detect L. intracellularis based on the conserved region of the 16S ribosomal RNA gene. The optimal reaction conditions of the real-time LAMP was 65 °C for 60 min. The LAMP products could be detected by both real-time turbidity and direct visual inspection. The assay was specific for L. intracellularis, as no cross-reaction was observed with other pathogens. The detection limit of the real-time LAMP assay was 1.4 × 10−1pg of L. intracellularis DNA, which was the same as that of real-time PCR and approximately 100 times more sensitive than that of conventional PCR. Of the 136 clinical samples, L. intracellularis DNA was identified in 60 samples by real-time LAMP, which was the same as real-time PCR and higher than conventional PCR (36.8%, 50/136). The specific, sensitive and rapid real-time LAMP assay developed in this study could be a useful alternative tool in point-of-care (POC) diagnosis of L. intracellularis infection.

Síndrome de enterotiflocolitis aguda por "Klebsiella" sp. en un caballo pura raza española. Reporte de un caso

Were study a horse ( Equus caballus ), Purebred Spanish Horse, 6 years old, intact male sex, weight about 550kg, from equestrian center in Fregenal Sierra-Extremadura, Spain. History of acute diarrhea, are apply conventional treatment (hydration, anti-inflammatory and antibiotic). Physical examination showed severe profuse, fetid diarrhea deep red, tachypnea. The physiological parameters were: heart rate 60 bpm, respiratory rate 39 rpm and mucous cyanotic. Temperature: 40°C. Hematological examination showed severe leucopenia, decreased total serum protein, albumin and globulin also diminished. Serum chemistry evidenced severe hyponatremia and hypokalemia, with high levels of chlorine indicating metabolic acidosis. A stool analysis, which was negative and showed no eggs or larvae in the samples studied was performed. The microbial culture allowed the isolation of Klebsiella sp. and susceptibility testing showed sensitivity to ampicillin, Cetafzidine, Ciprofloxacin, Cefepine, gentamicin, imipenem, meropenem, Piperaciclina, piperacillin / tazobactam and trimethoprim sulfa resistance. The horse presented systemic complications associated with endotoxemia and death 36 hours after the onset of diarrhea. At necropsy, severe bleeding was observed enterotiflocolitis. The histological sections showed proliferative enteritis characterized by lymphocyte and mononuclear inflammatory infiltrate plasmocytorious mucosa and submucosa, coagulation necrosis, bacteria and short rod type morphology with no specific grouping. In conclusion a case of acute syndrome enterotiflocolitis reported Klebsiella sp. on a horse Purebred Spanish.

Campylobacter hyointestinalis Isolated from Pigs Produces Multiple Variants of Biologically Active Cytolethal Distending Toxin.

Campylobacter hyointestinalis isolated from swine with proliferative enteritis often is considered to be pathogenic. While the precise virulence mechanisms of this species remain unclear, we have recently identified a cytolethal distending toxin (cdt) gene cluster in C. hyointestinalis isolated from a patient with diarrhea (W. Samosornsuk et al., J Med Microbiol, 27 July 2015, http://dx.doi.org/10.1099/jmm.0.000145). However, the sequences of the cdt genes in C. hyointestinalis were found to be significantly different and the gene products are immunologically distinct from those of other Campylobacter species. In this study, we demonstrate the presence of a second variant of the cdt gene cluster in C. hyointestinalis, designated cdt-II, while the former is named cdt-I. Sequencing of the cdt-II gene cluster and deduced amino acid sequences revealed that homologies between the subunits CdtA, CdtB, and CdtC of ChCDT-I and ChCDT-II are 25.0, 56.0, and 24.8%, respectively. Furthermore, the CdtB subunit of ChCDT-II was found to be immunologically unrelated to that of ChCDT-I by Ouchterlony double gel diffusion test. Recombinant ChCDT-II also induced cell distention and death of HeLa cells by blocking the cell cycle at G2/M phase. Interestingly, the cdt-II genes were detected in all 23 animal isolates and in 1 human isolate of C. hyointestinalis, and 21 of these strains carried both cdt-I and cdt-II gene clusters. Altogether, our results indicate that ChCDT-II is an important virulence factor of C. hyointestinalis in animals.

Prevalence of Lawsonia intracellularis Infections in Pig Herds from the Western Romania

Abstract Porcine proliferative enteritis (PPE) is an important enteric disease and is widespread in intensive pig production. It is caused by Lawsoniaintracellularis, intracellular bacteria which affect more frequently postweaned pigs between 6 and 20 weeks of age. The aim of the study described in this paper was to obtain data on the prevalence of Lawsoniaintracellularis infections in Romanian pig herds. To realize this we used “Lawsonia FIRST test™” kit (MicroCoatBiotechnologie GmbH), a qualitative single-use test designed to be used for the detection of Lawsoniaintracelluaris in porcine feces. The samples were collected from four wean-to-finish herds from the west part of Romania, 15 samples/herd, from pigs with ages between90 and 140 days. These herds were from different counties as it follows: Timis – 2 herds, Bihor and Hunedoara – one herd from each one. This study showed that Lawsoniaintracellularis infection percent is different between herds, varying between 0% (herd 1 from Timiscounty) and 80% (herd 2 from Timis county). In herds from Bihor and Hunedoara counties the infection percent was 60, respectively 46.6%. The results indicate that infection with Lawsoniaintracelluaris is very widespread in investigated pig herds– 46.6% of samples were positive – and it occurs in herds with digestive disorders and in herds without clinical symptoms.

Prevalence, intensity, and pathological lesions of Eimeria infection in goats in western Iran

The present study was carried out to survey the prevalence, intensity and pathological lesions of coccidia in 350 goats in western Iran from March 2012 to February 2013. The overall prevalence of coccidial infection was 83.43 % (292/350), with prevalence of 84 % (168/200) for adult goats and 82.66 % (124/150) for kids. Nine species of Eimeria were identified, namely, Eimeria arloingi, Eimeria parva, Eimeria ninakohlyakimovae, Eimeria pallida, Eimeria christenseni, Eimeria caprina, Eimeria hirci, Eimeria faurei, and Eimeria granulosa. The most common Eimeria species was E. arloingi (85.96 %), and E. granulosa was observed in the smallest proportion (3.08 %) of samples. Concurrent infection with two to five species was present in 78.45 % of positive samples. On gross examination, minimal changes were observed as thickening of the intestinal mucosa associated with a few scattered small whitish foci in the jejunum and ileum and advanced lesions as a pseudoadenomatous pattern in the mucosa and a cerebriform pattern on the serosal surface of the jejunum and ileum. The main histopathological lesion was proliferative enteritis associated with the presence of the developmental stages of parasite in the epithelial cells of the villi and crypts of the jejunum, ileum, and cecum. The results of the present investigation revealed that prevalence of coccidial infection is significantly high in western Iran and also have implications for the control of coccidial infections in the goat industry.

Prevalence and pathology of coccidiosis in goats in southeastern Iran.

Coccidiosis is an economically disease that caused by Eimeria spp. Small and large intestines are target tissues of this protozoan parasite. The aim of this study was to determine the prevalence of coccidial infection and pathology of coccidiosis of goats in Kerman, southeastern Iran, from February 2010 to July 2011. Faecal samples (approximately 3-5g) were obtained from the rectum of 208 goats. The samples were determined microscopically for the presence of oocysts. Eimeria species were identified following sporulation of faeces in a thin layer of 2.5% potassium dichromate for one or 2weeks at 27°C. Results showed the presence of multiple species in 187 out of 208 analyzed samples (89.91%). Nine different Eimeria species were identified: E. arloingi (68.26%), E. christenseni (50.9%), E. ninakohlyakimovae (41.8%), E. caprina (31.7%), E. alijevi (29.8%), E. jolchijevi (26.92%), E. apsheronica (22.59%), E. hirci (11.05%), and E. pallida (5.2%). Goats were considered in three age groups (less than 2years old, 2-3years old and over 3years old). Obtained data indicated that coccidiosis was relatively common among the goats in this area. The highest rate of oocyte counts were observed in goats over 3years old and females were more affected than male. The sex and age of the goat had not significant effects on the prevalence of coccidiosis, as well. There was no significant difference in oocyte per gram during different months. Coccidial lesions occurred in the jejunum and ileum more than other parts of intestine. Grossly, the affected tissues revealed non-pedunculated whitish nodules. Histopathologically, these nodules were characterized as proliferative enteritis with presence of different stages of the Eimeria in the hyperplastic epithelium and mild inflammatory reaction. Parasitological, gross and microscopic examinations revealed Eimeria infection was common in goats of Kerman, southeastern Iran.

Documented and potential research impacts of subclinical diseases in zebrafish.

The zebrafish (Danio rerio) has become a very important animal model in biomedical research. In contrast with other models, such as mice, there has been relatively little documentation or control of subclinical disease in zebrafish research facilities. Several infectious and noninfectious conditions are consistently detected by histopathology in apparently healthy D. rerio. The most commonly observed infectious agent in zebrafish is Pseudoloma neurophilia, which is a microsporidian organism that targets the central nervous system, peripheral nerves, and occasionally other tissues. Mycobacteriosis, caused by Mycobacterium chelonae and other species, is also a frequent finding. Less commonly encountered agents include Pseudocapillaria tomentosa, which can cause extensive proliferative enteritis, and a myxozoan (Myxidium sp.) that inhabits the urinary tract but appears to cause few if any pathological changes. Noninfectious diseases that are often clinically unapparent in zebrafish include hepatic megalocytosis, bile and pancreatic ductal proliferation, and neoplasms of the ultimobranchial gland, gastrointestinal tract, and testis. To date, there is little information on the degree to which these conditions may impact research in subclinically affected fish, but there is reason to believe that they should be considered as potentially significant causes of nonprotocol variation in experiments. Therefore, it is imperative that research facilities monitor their stocks for the presence of these occult diseases and be aware of their existence when interpreting study results. Furthermore, for underlying disease conditions that cannot be readily eradicated, it is essential to determine the physiological and immunological changes that they elicit in zebrafish. Understanding the cause, modes of transmission, and distribution of the pathogens would provide useful information for the development of control and prevention strategies.

Experimental Reproduction of Porcine Circovirus Type 2 (PCV2)-Associated Enteritis in Pigs Infected with PCV2 Alone or Concurrently with Lawsonia intracellularis or Salmonella typhimurium

Porcine circovirus (PCV)-associated disease (PCVAD) has emerged to become one of the most economically important pig diseases globally. One of the less commonly recognized clinical manifestations of PCVAD is PCV2 type 2 (PCV2)-associated enteritis in growing pigs; however, experimental confirmation of the ability of PCV2 alone or PCV2 coinfection with other agent(s) to induce enteritis is lacking. In this study, 120 specific-pathogen-free (SPF) pigs were divided randomly into six groups: controls (negative control pigs), PCV2 (inoculated with PCV2), LAW (inoculated with Lawsonia intracellularis), SALM (inoculated with Salmonella typhimurium), PCV2-LAW (concurrently inoculated with PCV2 and Lawsonia intracellularis) and PCV2-SALM (concurrently inoculated with PCV2 and Salmonella typhimurium). One half of the pigs in each group were subject to necropsy examination 14 days postinoculation (dpi) and the remaining pigs were examined at 28 dpi. The average daily weight gain was not different (P>0.05) between groups. Individual pigs inoculated orally with PCV2 regardless of coinfection status (2/10 PCV2, 1/10 PCV2-LAW, 3/10 PCV2-SALM) developed PCVAD with diarrhoea and reduced weight gain or weight loss between 14 and 28 dpi. Those pigs had characteristic microscopic lesions in lymphoid and enteric tissues associated with abundant PCV2 antigen. Enteric lesions were characterized by necrosuppurative and proliferative enteritis with crypt elongation and epithelial hyperplasia in LAW and PCV2-LAW pigs by 14 dpi, ulcerative and necrosuppurative colitis in SALM and PCV2-SALM pigs by 14 dpi, and lymphohistiocytic enteritis with depletion of Peyer's patches in PCV2, PCV2-SALM and PCV2-LAW pigs by 28 dpi. To the authors' knowledge, this is the first report documenting that under experimental conditions, PCV2 can induce enteritis independently from other enteric pathogens and that oral challenge is a potentially important route and perhaps the natural route of PCV2 transmission in growing pigs.

Detection of Lawsonia intracellularis in Formalin-fixed Porcine Intestinal Tissue Samples: Comparison of Immunofluorescence and In-situ Hybridization, and Evaluation of the Effects of Controlled Autolysis

Two methods, an immunofluorescence assay (IFA; with a Lawsonia intracellularis-specific monoclonal antibody) and fluorescent in-situ hybridization (FISH; with a specific oligonucleotide probe targeting 16S ribosomal RNA of the bacterium), were compared for their ability to detect L. intracellularis (the cause of porcine proliferative enteritis [PE]) in formalin-fixed samples of intestinal tissue. Of 69 intestinal samples with gross lesions of PE, 63 were positive by both FISH and IFA, but six were positive only by IFA. This indicated that the sensitivity of FISH was 91% that of IFA. However, both methods had a specificity of 100%. Fifty normal porcine intestines were negative by both tests. IFA was much less susceptible than FISH to the effects of autolysis. Thus, three of nine samples from pigs with PE were FISH-negative after being kept at 20 degrees C for 4 days, and seven were FISH negative after 2 weeks; after 4 weeks at this temperature, however, six of the nine samples were still IFA positive. After being kept at 4 degrees C for 12 weeks, the majority of samples (> or = 66%) were positive by both methods.

Occurrence of Cryptosporidium sp. in snakes in Japan

The aim of this study was to determine the prevalence of Cryptosporidium in snakes in Japan. Fecal samples or intestinal contents of 469 snakes, consisting of five species, were analyzed and Cryptosporidium oocysts were detected only from the Japanese grass snake Rhabdophis tigrinus. The mean prevalence of Cryptosporidium sp. in Japanese grass snakes was approximately 26% in the region studied. Histopathological observations revealed that the organism caused proliferative enteritis in the small intestine. Sequence analysis of a fragment of the small subunit rRNA gene has shown that the partial sequence of Cryptosporidium sp. isolated from the snakes was identical to that of the Cryptosporidium snake genotype W11 from New Guinea viper boa.

Pathologic lesions of naturally occurring coccidiosis in sheep and goats

Small ruminant coccidiosis is a contagious protozoal disease that especially occurs in kids and lambs, with a worldwide distribution. In this study, a total number of 21 small ruminants including six goats and 15 sheep with ages between 2 weeks to 6 years old with history of depression, loss of appetite, yellow to dark watery diarrhea, progressive dehydration, and emaciation were referred for diagnosis of the disease. At necropsy, gross lesions were seen mostly in the jejunum, ileum, cecum, and sometimes in proximal colon. Three cases had minimal lesions including a few scattered whitish non-pedunculated to pedunculated nodules on the mucosa of the jejunum and ileum. Eighteen cases had marked lesions including numerous small whitish non-pedunculated nodules on the mucosa of the jejunum, ileum, cecum, and proximal colon. Advanced cases had adenomatous-like mucosa and a cerebriform or gyrate pattern on the serosal surface. Microscopically, lesions in both minimal and marked cases were similar to proliferative enteritis except the extent of lesions and amount of inflammatory reaction. In marked cases, the epithelial cells of hyperplastic crypts and villi of the jejunum, ileum, cecum, and proximal part of colon were full of developmental stages of Eimeria, especially progamonts. The giant schizonts were easily discernible in five cases. There was no histologic evidence of presence of developmental stages of Eimeria in the duodenum, distal colon, rectum, submucosal tissues, or mesenteric lymph nodes. In conclusion, this study showed no differences between sheep and goat cases with regards to clinical signs, gross and histopathologic lesions. The most common lesions were in the jejunum, ileum, and cecum, grossly as non-pedunculated whitish nodules and microscopically, as proliferative enteritis with presence of developmental stages of the Eimeria in the hyperplastic enterocytes.

Distinction between Porcine Circovirus Type 2 Enteritis and Porcine Proliferative Enteropathy caused by Lawsonia intracellularis

The presence of porcine circovirus type 2 (PCV2) was studied immunohistochemically in formalin-fixed, paraffin wax-embedded samples of intestinal tissue from 80 pigs with a clinical history suggestive of Lawsonia intracellularis-associated diarrhoea. Histopathologically, enteritis of varying intensity was diagnosed in 64 of the pigs. Of these 64 animals, 34 (18%) were infected with both PCV2 and L. intracellularis. Of the remaining 30 cases of enteritis, 23 (77%) were attributed to PCV2 infection alone. The PCV2-associated enteritis cases showed necrotizing ileitis and colitis, indistinguishable macroscopically from proliferative enteritis (PE) due to L. intracellularis. Histopathologically, L. intracellularis-positive intestines showed adenomatous proliferation of crypt enterocytes, whereas PCV2 enteritis was characterized by histiocytosis of varying intensity, with PCV2-positive cells in the submucosa, lamina propria and crypt epithelium, as well as in the lymphoid tissue of the ileum and colon. Multinucleated giant cells, however, were seen in both infections. PCV2 was about three times more likely to be detected in L. intracellularis-negative than in L. intracellularis-positive samples (P<0.001). There was no association between PCV2 and other intestinal bacterial pathogens. The study demonstrated that PCV2 enteritis should be borne in mind in the differential diagnosis of L. intracellularis infection in pigs aged 2-4 months with a clinical history of diarrhoea.

Pathogenic Effiects of the Coccidium Eimeria ninakohlyakimovae in Goats

Twenty-four coccidia-free goats were reared artificially in indoor cages and allocated to 6 groups of 4 animals each. At 20 days of age, goats in groups 1-3 received 10(4),10(5) and 10(6) sporulated oocysts of Eimeria ninakohlyakimovae per goat, respectively, each as a single dose. Goats in group 4 received daily doses increasing over a 3-week period, starting with 100/day for the first week, followed by 1000, and 10,000/day in weeks 2, 3, respectively. Goats in group 5 received 10(4) oocysts following a challenge dose of 10(6) oocysts on day 32. Goats in group 6 were kept as uninoculated controls. Infected animals showed diarrhoea and weight loss. Goats in group 4 showed longer periods of diarrhoea and patency than other infected goats. Goats in group 5 showed the same severe clinical signs as those in group 3 but produced very low oocyst output after a challenge dose. The diarrhoea was associated with a reduction in alkaline phosphatase activity and increases in packed cell volume and haemoglobin. No significant differences were found in serum aspartate aminotransferase, alanine aminotransferase, total protein, albumin, globulin, Na+, K+,Cl- between groups during 48 days after inoculation. There were no serum enzyme indications of damage to the liver. Histological examination performed 100 days after inoculation revealed that inoculated goats had mild subacute to chronic proliferative enteritis in the lower small intestine and the large intestine, and the mesenteric lymph nodes, gallbladders and livers also showed slight histological lesions. The results showed that E. ninakohlyakimovae was highly pathogenic.

Lawsonia intracellularisProliferative Enteropathy in a Filly

Proliferative enteropathy (PE) caused by the obligate intracellular bacterium Lawsonia intracellularis is a disease of high economic impact in swine worldwide. In most other species the disease occurs as a sporadic infection. This paper reports a PE caused by L. intracellularis in a 9-month-old Pura Raza Española filly with a history of profuse diarrhoea. Pathological lesions consisted of a severe proliferative enteritis associated with argyrophilic bacteria in the apical cytoplasm of proliferating crypt epithelium. Characteristic PCR products confirmed the presumptive diagnosis of L. intracellularis infection. To our knowledge this is the first report of PE in a horse in Europe caused by L. intracellularis.

Progressive Proliferative and Dysplastic Typhlocolitis in Aging Syrian Hamsters Naturally Infected with Helicobacter spp.: A Spontaneous Model of Inflammatory Bowel Disease

Helicobacter spp. have been implicated in a variety of gastrointestinal tract diseases, including peptic ulcer disease, gastric cancer, and inflammatory bowel disease (IBD), in humans and animals. Although most models of IBD are experimentally induced, spontaneous or natural models of IBD are rare. Herein, we describe a long-term study of chronic, progressive lesions that develop in the distal portion of the large bowel of unmanipulated Syrian hamsters naturally infected with Helicobacter spp. Twenty-four Syrian hamsters of three age groups (group A, 1 month [n = 4], group B, 7-12 months [n = 12], group C, 18-24 months [n = 12]), underwent complete postmortem examination. Results of microbial isolation and polymerase chain reaction and restriction fragment length polymorphism analyses confirmed the presence of Helicobacter spp. infection in the distal portion of the large bowel of all animals. Additionally, confounding pathogens, such as Clostridium difficile, Lawsonia intracellularis, and Giardia spp. that can cause proliferative enteritis, were absent in the hamsters of this study. Histopathologic scores for inflammation (P < 0.01), hyperplasia (P < 0.01), and dysplasia (P < 0.05) were significantly higher in the ileocecocolic (ICC) junction of animals in group C, relative to group A. Dysplastic lesions of various grades were detected in 5 of 11 hamsters in group C. Interestingly, the segment of the bowel that is usually colonized by Helicobacter spp. in hamsters had the most severe lesions. One hamster of group C developed a malignant fibrous histiocytoma, whereas another hamster developed a round cell sarcoma originating from the ICC junction. Thus, lesions in the distal portion of the large bowel of aging hamsters naturally colonized with Helicobacter spp. warrants developing the hamster as an animal model of IBD and potentially IBD-related cancer.

PROLIFERATIVE ENTERITIS ASSOCIATED WITH LAWSONIA INTRACELLULARIS IN A JAPANESE MACAQUE (MACACA FUSCATA)

A 2.5-yr-old, intact male Japanese macaque (Macaca fuscata) was observed to have a thickened ileum during exploratory laparotomy. Lawsonia intracellularis-associated proliferative enteritis was diagnosed using histopathology (Warthin-Starry stain), immunohistochemistry, and polymerase chain reaction analysis of the ileal biopsy. The animal developed transient diarrhea and severe hypoproteinemia 16 days after surgery but recovered with intensive treatment using azithromycin. Given the fact that very specific tests are required for identifying this organism, L. intracellularis may be underdiagnosed in nonhuman primates.