Host Th1/Th2 immune response to Taenia solium cyst antigens in relation to cyst burden of neurocysticercosis.

Neurocysticercosis (NCC), Taenia solium larval infection of the brain, is an important cause of acquired seizures in endemic countries, which relate to number, location and degenerating cysts in the brain. Multicyst infections are common in endemic countries although single-cyst infection prevails in India. Single-cyst infections in an endemic country suggest a role for host immunity limiting the infection. This study examined ex vivo CD4(+) T cells and in vitro Th1 and Th2 cytokine responses to T. solium cyst antigens of peripheral blood mononuclear cells of healthy subjects from endemic and nonendemic regions and of single- and multicyst-infected patients for association with cyst burden of NCC. T. solium cyst antigens elicited a Th1 cytokine response in healthy subjects of T. solium-endemic and T. solium-non-endemic regions and those with single-cyst infections and a Th2 cytokine response from subjects with multicyst neurocysticercosis. Multicyst neurocysticercosis subjects also exhibited low levels of effector memory CD4(+) T cells. Th1 cytokine response of T. solium exposure and low infectious loads may aid in limiting cyst number. Th2 cytokines and low effector T cells may enable multiple-cyst infections to establish and persist.

Analysis of the mucosal immune responses induced by single and trickle infections with the bovine abomasal nematode Ostertagia ostertagi.

The purpose of this study was to provide more information on the kinetics of the immunological changes occurring in the abomasal mucosa after single and trickle infections with the bovine parasite Ostertagia ostertagi. The time course analysis of gene expression revealed that the major changes coincided with the emergence of adult worms from the gastric glands. These changes consisted of a simultaneous upregulation of Th1- and Th2-type cytokines. In addition, a single O. ostertagi infection elicited an upregulation of the epithelial-derived cytokine IL33, while TSLP expression levels were not impacted. Apart from the massive increase in inflammatory cytokines IL6, IL17 and IL21, O. ostertagi infection also elicited an upregulation of the immunosuppressors TGFB, IL10 and ARG1, as well as NK and γδ-T cell markers. Furthermore, the cytotoxic factors granulysin, perforin and granzyme B were upregulated following an O. ostertagi infection. Analysis of cytokine transcript levels in animals receiving trickle infections for 60 days showed a similar trend as observed following a single infection except for IL33, IL6, GATA-3, TBX21 and NCR1, which were no longer upregulated after trickle infections. Finally, the long trickle infections were associated with mucosal eosinophilia and mastocytosis.

Giardia duodenalis stimulates partial maturation of bovine dendritic cells associated with altered cytokine secretion and induction of T-cell proliferation.

Giardia duodenalis is an important intestinal parasite in animals and humans. The role of dendritic cells (DC) in the initiation of the immune response against G. duodenalis is poorly documented. The aim of this study was to test the hypothesis that G. duodenalis interferes with bovine DC function. Therefore, the effect of trophozoites and excretion/secretion products on bovine monocyte-derived dendritic cells (MoDC) was investigated. We assessed MoDC maturation and cytokine production of G. duodenalis-stimulated MoDC and the ability of these MoDC to take up antigen and induce lymphocyte proliferation. Little or no upregulation of maturation markers CD40 and CD80 was measured, but MHCII expression was increased after stimulation with low parasite concentrations. A dose-dependent decrease in ovalbumin uptake was observed in G. duodenalis-stimulated MoDC. In addition, stimulated MoDC induced proliferation of CD3(-) , γδ-T-cells and TCRαß(+) CD4(+) and CD8(+) T-cells. Increased transcription of TGF-ß was shown in CD4(+) T cells, and increased TNF-α, TGF-ß, IL-10 and IL-4 were seen in γδ-T-cells. We found no evidence that G. duodenalis has a regulatory or inhibitory effect on bovine MoDC. MoDC stimulated with G. duodenalis are functionally active and able to induce proliferation of T cells that produce both pro- and anti-inflammatory cytokines.

Recent advances in the diagnosis, impact on production and prediction of Fasciola hepatica in cattle.

Fasciola hepatica is a pathogenic trematode parasite of ruminants with a global distribution. Here, we briefly review the current epidemiology of bovine fasciolosis in Europe and discuss the progress made over the last decade in the diagnosis, impact on production and prediction of F. hepatica in cattle. Advances in diagnosis have led to significantly improved coprological and serological methods to detect presence of infection. Diagnostic test results have been correlated with intensity of infection and associated production losses, unravelling the impact on carcass weight and milk yield in modern cattle production systems. The economic impact of fasciolosis may, however, go beyond the direct impacts on production as evidence shows that F. hepatica can modulate the immune response to some co-infections. Control of bovine fasciolosis remains hampered by the limitations of the currently available flukicidal drugs: few drugs are available to treat dairy cows, many have low efficacies against juvenile stages of F. hepatica and there is evidence for the development of drug resistance. This makes research into the prediction of risk periods, and thus the optimum application of available drugs more pertinent. In this field, the recent research focus has been on understanding spatial risk and delivering region-specific spatial distribution maps. Further advances in epidemiological and economic research on bovine fasciolosis are expected to deliver farm-specific economic assessments of disease impact, to leverage non-chemotherapeutic management options and to enhance a more targeted use of anthelmintics.

Gene expression analysis of ABC transporters in a resistant Cooperia oncophora isolate following in vivo and in vitro exposure to macrocyclic lactones.

Members of the ATP-binding cassette (ABC) transporter family (P-glycoproteins, Half-transporters and Multidrug Resistant Proteins) potentially play a role in the development of anthelmintic resistance. The aim of this study was to investigate the possible involvement of ABC transporters in anthelmintic resistance in the bovine parasite, Cooperia oncophora. Partial sequences of 15 members of the ABC transporter protein family were identified, by mining a transcriptome dataset combined with a degenerate PCR approach. Reverse transcriptase PCR showed that most of the ABC transporters identified were constitutively transcribed throughout the life cycle of C. oncophora. Constitutive differences in gene transcript levels between a susceptible and resistant isolate were only observed for Con-haf-9 and Con-mrp-1 in eggs of the resistant isolate, while no differences were observed in L3 or the adult life stage. Analysis of resistant adult worms, collected from calves 14 days after treatment with either ivermectin or moxidectin, showed a significant 3- to 5-fold increase in the transcript levels of Con-pgp-11 compared to non-exposed worms. Interestingly, a 4-fold transcriptional up-regulation of Con-pgp-11 was also observed in L3 of the resistant isolate, after in vitro exposure to different concentrations of ivermectin, whereas this effect was not observed in exposed L3 of the susceptible isolate. The results suggest that the worms of this particular resistant isolate have acquired the ability to up-regulate Con-pgp-11 upon exposure to macrocyclic lactones. Further work is needed to understand the genetic basis underpinning this process and the functional role of PGP-11.

Myospherulosis as a complication of functional endoscopic sinus surgery: a double case report.

INTRODUCTION: Paraffinomas (also known as 'sclerosing lipogranulomas' or 'myospherulosis') are a widely acknowledged complication of cosmetic paraffin injections but they are rare following functional endoscopic sinus surgery. CASE PRESENTATIONS: Our first case features a 45-year-old woman presenting with a peri-ocular swelling two weeks after functional endoscopic sinus surgery. The procedure was complicated by a fractured lamina papyracea. A nasal packing with antibiotic ointment was left in situ. Initially, the inflammation was controlled successfully with corticosteroids but the swelling persists to this day. Our second case is a 45-year-old man who suffered from a recurrent swelling of the right eyelid after endoscopic sinus surgery. Multiple treatments with oral antibiotics and corticosteroids brought about no improvement. Debulking surgery was performed and a PDS film was placed between the peri-orbita and the bony orbital floor but the swelling recurred. The patient finally consulted a plastic surgeon as a last resort, but the reconstructive procedure only exacerbated the clinical picture. In both cases a biopsy was performed which established the foreign body reaction typical of a paraffinoma. At present, both patients still suffer from this condition. CONCLUSION: The complete resection of a paraffinoma is seldom possible because of diffuse infiltration and recurrence is very likely. We therefore conclude that paraffin-based ointments should not be used with nasal packing after sinus surgery, especially when there has been a lesion involving the orbital wall.

The economic effects of whole-herd versus selective anthelmintic treatment strategies in dairy cows.

Current control practices against gastrointestinal nematodes in dairy cows rely strongly on anthelmintic use. To reduce the development of anthelmintic resistance or disposition of drug residues in the environment, novel control approaches are currently proposed that target anthelmintic treatment to individual animals instead of the whole herd. However, such selective treatment strategies come with additional costs for labor and diagnostics and, so far, no studies have addressed whether they could be economically sustainable. The objectives of this study were to (1) investigate the economic effects at farm level of whole-herd versus more selective anthelmintic treatment strategies in adult dairy cows, and (2) determine how these economic effects depend on level of infection and herd size. A Monte Carlo simulation, fed by current epidemiological and economical knowledge, was used to estimate the expected economic effects and possible variation of different control strategies under Belgian conditions. Four treatment strategies were compared with a baseline situation in which no treatments were applied: whole herd at calving (S1), selective at calving with (S2) or without (S3) treatment of the first-calf cows, and whole-herd when animals are moved from grazing to the barn in the fall (housing treatment, S4). The benefit per lactation for an average dairy herd varied between -$2 and $131 (average $64) for S1, between -$2 and $127 (average $62) for S2, between -$17 and $104 (average $43) for S3, and between -$41 and $72 (average $15) for S4. The farmer's risk associated with any treatment strategy, as indicated by the width of the 95% credible intervals of economic benefit of anthelmintic treatment, decreased with increasing level of exposure, as assessed by bulk tank milk ELISA. The order of the different strategies when sorted by expected benefit was robust to changes in economic input parameters. We conclude that, on average, strategies applying anthelmintic treatment at calving outperform a strategy applying treatment at housing. Within the strategies that applied treatment at calving, more selective treatment strategies can be economically sustainable. However, given the large variation in possible benefits within each treatment strategy, decision support systems are needed to account for the multitude of cow, epidemiological, and economic factors that determine the economics of nematode control and select the optimal treatment strategy for a specific farm.

Immunizing pigs with Ascaris suum haemoglobin increases the inflammatory response in the liver but fails to induce a protective immunity.

To determine whether purified Ascaris suum haemoglobin (AsHb) is a suitable vaccine candidate for the control of Ascaris infections, pigs were vaccinated with AsHb in combination with QuilA adjuvant and challenged with A. suum eggs. The number of liver lesions and worms in the intestine was assessed on day 14, 28 and 56 post-infection (p.i.). No significant differences were found in the number of worms recovered between vaccinated and control pigs on any of these days. However, significantly more white spots were counted on the livers of vaccinated pigs on day 14 (+86%) and day 28 (+118%) p.i. compared with nonvaccinated controls. To investigate whether the increased immunoreactivity against the liver stage L3s in vaccinated pigs was triggered by and directed against AsHb, the transcription and expression of AsHb in this larval life stage was analysed by RT-PCR and immunoblotting. The results showed that neither the AsHb transcript nor protein was detectable in freshly hatched L3. However, the immunoblot analysis showed that vaccination with AsHb resulted in the production of antibodies binding to several other antigens of the L3, suggesting that these might be involved in the increased white spot development.

Assessment of a 27-kDa antigen in enzyme-linked immunosorbent assay for the diagnosis of fasciolosis in Vietnamese patients.

Fasciolosis has emerged as an important zoonotic disease in many parts of the world. In recent years, an increasing number of human cases were reported in Vietnam. In this study, the 27-kDa component protein from the excretory/secretory production of adult Fasciola gigantica, purified by high performance liquid chromatography, was assessed in an enzyme-linked immunosorbent assay (ELISA) to detect antibodies against Fasciola spp. for diagnosis of human fasciolosis. The ELISA showed a high sensitivity (100%) and specificity (97.67%) when tested on patients with fasciolosis, other parasitic infections, cholangiocarcinoma and on healthy controls. The assay was applied for diagnosis on 143 patients in the Viet Duc-Hanoi hospital who presented with clinical signs of liver disease and lesions in their livers as shown by imaging techniques. Antibodies were found in 37 (25.9%) of these patients, of whom only 3 shed Fasciola eggs in their stools (2.1%). The excellent response to triclabendazole treatment of 37 sero-positive patients confirmed the diagnosis of fasciolosis. This study demonstrated the diagnostic potential for human fasciolosis of the 27-kDa antigen ELISA. Fasciolosis should be considered in the differential diagnosis of hepatic disease in Vietnam.

Diffusion-weighted magnetic resonance imaging of the temporal bone.

This paper summarizes the value of diffusion-weighted magnetic resonance imaging in the evaluation of temporal bone pathology. It highlights the use of different types of diffusion-weighted magnetic resonance imaging in the different types of cholesteatoma, prior to first stage surgery and prior to second look surgery. The value of diffusion-weighted magnetic resonance imaging in the evaluation of pathology of the apex of the petrous bone and the cerebellopontine angle is also discussed.

Persistent left superior vena cava (PLSVC) connected to the left atrium.

A persistent left superior vena cava draining into the left atrium was diagnosed in an adult patient, scheduled for surgical correction of a large inferiorly located sinus venosus atrial septal defect. In the majority of cases a persistent left superior vena cava is found incidentally and causes little or no symptoms. Nevertheless, anaesthesiologist should be aware of its occurrence; because of different technical difficulties and clinical problems that can be encountered. Echocardiography plays an key role in the detection of a persistent left superior vena cava.

GLOWORM-PARA: a flexible framework to simulate the population dynamics of the parasitic phase of gastrointestinal nematodes infecting grazing livestock.

Gastrointestinal nematodes are a significant threat to the economic and environmental sustainability of keeping livestock, as adequate control becomes increasingly difficult due to the development of anthelmintic resistance in some systems and climate-driven changes to infection dynamics. To mitigate any negative impacts of climate on gastrointestinal nematode epidemiology and slow anthelmintic resistance development, there is a need to develop effective, targeted control strategies that minimise the unnecessary use of anthelmintic drugs and incorporate alternative strategies such as vaccination and evasive grazing. However, the impacts climate and gastrointestinal nematode epidemiology may have on the optimal control strategy are generally not considered, due to lack of available evidence to drive recommendations. Parasite transmission models can support control strategy evaluation to target field trials, thus reducing the resources and lead-time required to develop evidence-based control recommendations incorporating climate stochasticity. Gastrointestinal nematode population dynamics arising from natural infections have been difficult to replicate and model applications have often focussed on the free-living stages. A flexible framework is presented for the parasitic phase of gastrointestinal nematodes, GLOWORM-PARA, which complements an existing model of the free-living stages, GLOWORM-FL. Longitudinal parasitological data for two species that are of major economic importance in cattle, Ostertagia ostertagi and Cooperia oncophora, were obtained from seven cattle farms in Belgium for model validation. The framework replicated the observed seasonal dynamics of infection in cattle on these farms and overall, there was no evidence of systematic under- or over-prediction of faecal egg counts. However, the model under-predicted the faecal egg counts observed on one farm with very young calves, highlighting potential areas of uncertainty that may need further investigation if the model is to be applied to young livestock. The model could be used to drive further research into alternative parasite control strategies such as vaccine development and novel treatment approaches, and to understand gastrointestinal nematode epidemiology under changing climate and host management.

Evaluation of the therapeutic efficacy of praziquantel against schistosomes in seven countries with ongoing large-scale deworming programs.

The World Health Organization (WHO) recommends periodic assessment of the therapeutic efficacy of praziquantel (PZQ) to detect reduced efficacy that may arise from drug resistance in schistosomes. In this multi-country study (2014), we assessed the therapeutic efficacy of a single oral dose of PZQ (40 mg/kg) against Schistosoma mansoni (Brazil, Cameroon, Ethiopia, Mali, Madagascar and Tanzania), S. haematobium (Cameroon, Ethiopia, Mali, Tanzania and Zanzibar) and S. japonicum (the Philippines) infections in school-aged children, across a total of 12 different trials. Each trial was performed according to the standardized methodology for evaluating PZQ efficacy as described by the WHO. Overall, therapeutic efficacy, measured as the reduction in arithmetic mean of schistosome egg counts following drug administration (egg reduction rate; ERR), was high for all three schistosome species (S. mansoni: 93.4% (95%CI: 88.8-96.8); S. haematobium: 97.7% (95%CI: 96.5-98.7) and S. japonicum: 90.0% (95%CI: 68.4-99.3). At the trial level, therapeutic efficacy was satisfactory (point estimate ERR ≥90%) for all three Schistosoma species with the exception of S. mansoni in Cameroon where the ERR was 88.5% (95%CI: 79.0-95.1). Furthermore, we observed that in some trials individual drug response could vary significantly (wide 95%CI) and that few non-responsive individuals could significantly impact ERR point estimates. In conclusion, these results do not suggest any established reduced efficacy of the standard PZQ treatment to any of the three schistosome species within these countries. Nevertheless, the substantial degree of variation in individual responses to treatment in some countries underpins the need for future monitoring. The reported ERR values serve as reference values to compare with outcomes of future PZQ efficacy studies to ensure early detection of reduced efficacies that could occur as drug pressure continues increase. Finally, this study highlights that 95%CI should be considered in WHO guidelines to classify the therapeutic efficacy of PZQ.

Multilocus genotyping of Cryptosporidium and Giardia in non-outbreak related cases of diarrhoea in human patients in Belgium.

Stool samples from Belgian patients suffering from abdominal pain and/or diarrhoea were examined for Cryptosporidium and Giardia. Cryptosporidium-positive samples were genotyped using the 70 kDa heat shock protein and the 60 kDa glycoprotein (GP60) genes: C. hominis was identified in 54.2% and C. parvum in 45.8% of the samples. Sequencing at the GP60 locus indicated that subgenotype IbA10G2 of C. hominis and subgenotype IIaA15G2R1 of C. parvum were the most prevalent, although several other subgenotypes were identified. For Giardia, sequencing at the beta-giardin, triose phosphate isomerase (TPI) and glutamate dehydrogenase (GDH) genes revealed assemblage B as the most prevalent (74.4%) in human patients. A high degree of heterogeneity was found, especially on the beta-giardin gene, and to a lesser extent on the GDH gene. Furthermore, using a novel species-specific PCR based on the TPI gene, mixed infections with both assemblage A and B were detected in a large number (32.4%) of human patients, which might have important epidemiological implications.

Cross-protection between Trypanosoma congolense strains of low and high virulence.

The aim of this study was to assess the existence of possible cross-protection between Trypanosoma congolense strains of low and extreme virulence circulating in the same trypanosomiasis focus. Groups of six mice were infected using one of three strains of low virulence and challenged with one of three strains of extreme virulence. A group of six mice was used as control for each strain of low and extreme virulence. The results showed that mice infected with one of the strains of extreme virulence developed high parasitaemia and a significant drop of the PCV compared to mice infected with a strain of low virulence and challenged with one of the strains of extreme virulence. With an exception of one strain of extreme virulence (strain F), the survival time of mice infected with the strains of extreme virulence was shorter compared to mice infected with strains of low virulence and subsequently challenged with a strain of extreme virulence. These results suggest that in an area where trypanosomes of various virulence profiles circulate, livestock infected with T. congolense strains of low virulence can be protected against the adverse effects of extremely virulent T. congolense strains.

Giardia and other intestinal parasites in different dog populations in Northern Belgium.

The objectives of this study were to obtain data on the prevalence of intestinal parasites in different dog populations in northern Belgium, to estimate the zoonotic risk associated with these infections and to identify potential risk factors. Between 2004 and 2007 a total of 1159 faecal samples were collected from 451 household dogs, 357 dogs from breeding kennels and 351 dogs with gastrointestinal disorders. The samples from dogs with gastrointestinal disorders were sent to the diagnostic Laboratory for Parasitology at Ghent University by veterinary practitioners. In household dogs the prevalence of intestinal parasites was relatively low. Giardia was the most commonly found parasite (9.3%, CI 5.5-13.1), followed by Toxocara canis (4.4%, CI 2.7-6.8). Much higher infection rates were observed in kennel dogs, especially for Giardia spp. (43.9%, CI 37.8-50.0); T. canis (26.3%, CI 21.8-31.2) and Cystoisospora spp. (26.3%, CI 21.8-31.2). Also in dogs with gastrointestinal problems, Giardia spp. (18.1%, CI 13.1-23.1), Cystoisospora spp. (8.8%, CI 6.1-12.3) and T. canis (7.4%, CI 4.9-10.7) were the most frequently detected parasites. In all dog populations pups were more frequently infected with Cystoisospora (P<0.0001 to P<0.05), Giardia (P<0.001 to P<0.05), and T. canis (P<0.0001 to P<0.001) than adult dogs, except for T. canis in household dogs, where this correlation was not significant. A significant association of anthelmintic treatment with T. canis infections was only observed within the household population. Household dogs with a higher number of treatments per year were more frequently infected with T. canis (P<0.05). There was a significant difference between the different breeding kennels for the occurrence of Cystoisospora, Giardia and T. canis (P<0.0001) and large kennels harboured relatively more infected animals than smaller breeding facilities (P<0.05). However, this was not significant for Giardia spp. Breed and gender did not affect the risk of an infection in any of the study populations. Toxocara and Giardia present a zoonotic risk, especially in household dogs, where the majority of Giardia positive samples (80%) belonged to the zoonotic assemblage A. In kennel dogs and clinically affected dogs the host-specific Giardia assemblages C and D were most prevalent (94% and 80%, respectively).

Monitoring the efficacy of ivermectin and albendazole against gastro intestinal nematodes of cattle in Northern Europe.

Faecal egg count reduction tests (FECRT) using ivermectin (IVM) and benzimidazole (BZ) were conducted to investigate the prevalence of anthelmintic resistance in gastro-intestinal nematodes on cattle farms in Germany, Belgium and Sweden in 2006 and 2007. Based on sufficient numbers of eggs prior to the study, between 3 and 10 farms per country were selected. 10-15 animals were randomly selected per farm and subcutaneously treated with 0.2 mg IVM/kg bodyweight (Ivomec, Merial). Faecal samples were collected individually from every animal on day 0 (treatment), day 7 (Belgium & Sweden) or 14 (Germany), and day 21 (Germany, Belgium and Sweden). Faecal egg counts (FEC) were performed at each sampling occasion to estimate the eggs per gram of faeces (EPG) and the reduction of eggs after treatment. The FECRT using IVM in 2006 revealed mean reduction of egg counts between 69-100% on day 7/14 (95% confidence interval (CI) 19-102) and 35-96% (95% CI 0-102) on day 21. Farms with a suggested problem of anthelmintic resistance have been re-visited in 2007 and except for one case all results obtained in 2006 were confirmed in 2007. Larvae obtained from faecal cultures were identified using microscopic identification keys or genus-specific real time PCR. Cooperia oncophora was the predominant species detected after treatment, but Ostertagia ostertagi was found in samples on 3 farms in Germany and 3 farms in Sweden post-treatment. In 2007 additionally a FECRT using benzimidazoles was conducted in Germany and Sweden. In Germany oral Valbazen (albendazole, 10%, Pfizer) was used at a concentration of 7.5 mg albendazole/kg bodyweight; in Sweden Valbazen Vet (albendazole, 10%, Orion Pharma) at a dose of 8 mg/kg was used. For benzimidazoles an efficacy of 100% was obtained on all tested farms in both countries. This is the first report of a multinational anthelmintic efficacy investigation in cattle in Europe. The results suggest that testing of anthelmintic efficacy should be performed more intensively due to possible insufficient efficacy of current drugs.

Optimizing physicians' instruction of PACS through e-learning: cognitive load theory applied.

This article outlines the strategy used by our hospital to maximize the knowledge transfer to referring physicians on using a picture archiving and communication system (PACS). We developed an e-learning platform underpinned by the cognitive load theory (CLT) so that in depth knowledge of PACS' abilities becomes attainable regardless of the user's prior experience with computers. The application of the techniques proposed by CLT optimizes the learning of the new actions necessary to obtain and manipulate radiological images. The application of cognitive load reducing techniques is explained with several examples. We discuss the need to safeguard the physicians' main mental processes to keep the patient's interests in focus. A holistic adoption of CLT techniques both in teaching and in configuration of information systems could be adopted to attain this goal. An overview of the advantages of this instruction method is given both on the individual and organizational level.

Magnetic resonance imaging of cholesteatoma: an update.

OBJECTIVE: To report on the value and limitations of new MRI techniques in pre- and post-operative MRI of cholesteatoma. The current value of magnetic resonance imaging (MRI) in diagnosing congenital, acquired, and post-operative recurrent or residual cholesteatoma is described. METHODOLOGY AND RESULTS: High resolution computed tomography (HRCT) is still considered the imaging modality of choice for detecting acquired or congenital middle ear cholesteatoma. However, MRI may provide additional information on the delineation and extension of cholesteatoma and on potential complications. Detecting post-operative residual or recurrent cholesteatoma with HRCT was shown to be inaccurate due to the technique's low sensitivity and specificity. CONCLUSIONS: Recently, improvements in MRI techniques have led to a more accurate diagnoses of cholesteatoma using delayed contrast enhanced T1-weighted imaging and diffusion-weighted imaging.

Mixed Giardia duodenalis assemblage A and E infections in calves.

A molecular epidemiological study was conducted on 100 dairy (499 calves) and 50 beef (333 calves) farms in Belgium to estimate the prevalence of different Giardia duodenalis assemblages in calves younger than 10 weeks of age. Positive samples from the epidemiological study and from a previous clinical study were selected and genotyped based on the amplification of the beta-giardin gene. To investigate the occurence of mixed assemblage A and E infections in calves, a novel assemblage-specific PCR was developed based on the triose-phosphate isomerase gene. The prevalence was 22% (95% Probability Interval (PI): 12-34%) in dairy calves and 45% (95% PI: 30-64%) in beef calves. In total, 120 Giardia-positive samples from dairy and beef calves collected in the epidemiological study and from clinically affected calves were identified based on the amplification of the beta-giardin gene. Overall G. duodenalis assemblage E was more prevalent (in 64% of the samples), although the majority (59%) of the dairy calves were infected with G. duodenalis assemblage A. Furthermore, mixed G. duodenalis assemblage A and E infections were identified in 31% of the calf samples (n=101) using the assemblage-specific PCR. We believe this is the first report of mixed infections in calves, and the results of the present study indicate that calves, although mainly infected with the host-specific G. duodenalis assemblage E, are frequently infected with the zoonotic assemblage A, either as a mixed or mono-infection, suggesting that calves might be underestimated as a potential zoonotic reservoir for human infections.