INTRODUCTION:Cyclosporine is a potent immunosuppressive agent used in veterinary medicine to treat a variety of inflammatory or immune mediated conditions. Many adverse effects are associated with this medication, however most of them rarely occur. A 5-year-old, female intact French bulldog was presented with multiple, multifocally distributed, severe hyperkeratotic and papillomatous/verrucous plaques. The dog was on long-term immunosuppressive treatment with cyclosporine for meningoencephalitis of unknown origin (MUO). It had an history of atopic dermatitis and calcinosis cutis. A papillomavirus infection was excluded by polymerase chain reaction (PCR), and histopathologic analysis revealed a chronic lymphoplasmacytic non-specific dermatitis, perifolliculitis and periadnexitis and focal folliculitis with papillomatous epidermal hyperplasia and orthokeratotic hyperkeratosis. The diagnosis of "cyclosporine-induced epidermal hyperplasia with secondary pyoderma" was made. Cyclosporine was discontinued and as an alternative mycophenolate mofetil was started to control the MUO. An antimicrobial treatment was prescribed for three weeks. After four months, the skin lesions had healed completely. To date after 2 years, the dog is still in remission. The occurrence of hyperplastic lesions associated with cyclosporine therapy have already been described in previous reports. Most of them resemble those of psoriasiform lichenoid dermatitis, although papilloma virus may be detected in some instances. The dog of the present case showed some peculiarities in the histopathological findings, and a papillomavirus involvement was ruled out with PCR. Like observed in a previous report, there was no correlation between cyclosporine blood level and the severity of dermatological changes. A discontinuation of cyclosporine resulted in complete healing in 4 months. This case highlights the importance of regular monitoring and follow-ups in patients on immunosuppressive therapy. Even rare side effects should always be considered in these cases.
Canine atopic dermatitis (CAD) is a prevalent inflammatory skin disease of dogs worldwide. Certain breeds such as the West Highland White Terriers (WHWT) are predisposed to suffer from CAD. Microbial dysbiosis is known to play a significant role in the pathogenesis of the disease, which is similar to its human counterpart, atopic dermatitis (AD). To date, no large cohort-study has been conducted in a predisposed dog breed to study the impact of the early-life microbiota on the development of CAD, as well as the possible implication of factors such as hygiene and access to the outdoors. In this study skin samples of 143 WHWT, including 109 puppies up to three weeks old and 34 parent dogs, from 17 breeders, were subjected to 16S rRNA gene and ITS2 amplicon sequencing to disclose the bacterial and fungal oral and skin microbiota, respectively. The oral samples served as a control group to confirm differences between haired and mucosal surfaces. The cutaneous microbiota differed between sample sites and age of the dogs. The season of sampling, geographical origin as well as hygiene status of the household and the access to the outdoors shaped the skin microbiota of the puppies significantly. However, we found that the individual early-life microbiota did not predispose for the later development of CAD.
BACKGROUND:The "hygiene hypothesis" suggests that a western way of life, including the extended use of anti-infective drugs, a high standard of hygiene and the resulting reduced exposure to microorganisms, could be one of the possible explanations for the increasing prevalence of allergic diseases in humans and animals.OBJECTIVES:we wished to evaluate if a nematode infection influenced IgE sensitization and allergic reactions to house dust mites in an experimental atopic dog model.METHODS:Twelve 10-week-old beagles were included: six of them were inoculated orally withToxocara canis (Tc) while six served as non-infected. Tc-specific IgE and IgG against Tc L3 E/S antigen (TcE/S antigen) were measured before and after Tc infection. All twelve dogs were sensitized epicutaneously to Dermatophagoides farinae (Df) house dust mites and then challenged twice epicutaneously with the mite. Total IgE and Df-specific IgE were measured before/after sensitization and after challenge. Local skin lesion scores were assessed before/after sensitization and after challenge while the duration of pruritus manifestations was measured by video after the second challenge.RESULTS:Toxocara canis -infected dogs exhibited higher levels of IgG and IgE levels against Tc, Df-specific IgE, total IgE but lower skin lesion scores and pruritus durations after challenge, compared to dogs not infested with this nematode.CONCLUSION & CLINICAL RELEVANCE:These observations suggest that a Tc infection increases the sensitization to Df in dogs. The possible protective effect against Df-induced clinical signs after allergen challenge should be confirmed in larger studies.
INTRODUCTION Allergen-specific immunotherapy (ASIT) is the only etiologic treatment of atopic dermatitis in dogs. In humans it has been shown that intralymphatic immunotherapy (ILIT) enhanced efficacy and patient compliance and reduced treatment time from 3 years to 8 weeks. As only safety data have been published yet, the aim of this study was to evaluate the clinical efficacy of ILIT in dogs. 20 atopic dogs underwent ILIT with alum-precipitated allergens administered every 4 weeks for 3 to 7 times in the popliteal lymph node. Pruritus (Hill score), CADESI (canine atopic dermatitis severety index), concurrent medications and adverse reactions were recorded initially and every 4 weeks for a total period of 24 weeks. The observed clinical response was good in 12/20 (60%) patients and improvement could be seen in some dogs already after 4 weeks. The median number of injections was 5.6. All dogs tolerated the procedure well and no adverse effects were recognized during or after ILIT. Therefore ILIT should be regarded as a safe alternative to subucaneous ASIT, enabling a faster clinical improvement with the same response rate.
Allergies are often suspected in cats and they are mainly hypersensitivity reactions against insect bites, food- or environmental allergens. Cats, with non flea induced atopic dermatitis, normally present with one oft he following reaction patterns: miliary dermatitis, eosinophilic dermatitis, selfinduced alopecia or head and neck excoriations. None of these reaction patterns is nevertheless pathognomonic for allergic dermatitis, therefore the diagnosis is based on the one hand on the exclusion of similar diseases on the other hand on the successful response on a certain therapy. Recently a study on the clinical presentation of cats with non flea induced atopic dermatitis was published. In this study certain criteria for diagnosing atopy in cats were proposed. For therapy of allergic cats cyclosporin, glucocorticoids, antihistamines, hypoallergenic diets and allergen specific immunotherapy are used. This article should provide a recent overview on the clinical symptoms, diagnosis and therapy of feline allergic dermatitis.
Bovine besnoitiosis, an economically important disease in cattle in some countries of Africa and Asia, is emerging in Europe. The definitive host of Besnoitia besnoiti, the causative agent of bovine besnoitiosis, is unknown and the transmission of the parasite is not completely understood. Sensitive and quantitative DNA detection methods are needed to determine whether serologically positive animals are infectious and to examine the role of vectors (e.g. haematophagous insects) in the transmission of the parasite. To this end, we established two different 5'-nuclease quantitative assays to detect B. besnoiti infection in cattle and to estimate the parasite load in samples (BbRT1 and BbRT2). These PCRs are based on the sequence of the internal transcribed spacer region 1 (ITS-1) of the ribosomal RNA gene. Tests with serial dilutions of B. besnoiti genomic DNA in a buffer containing 100 ng/μl bovine DNA revealed a detection limit of 0.01 pg genomic B. besnoiti DNA. Reliable quantification was possible in samples containing ≥1 pg B. besnoiti genomic DNA with a coefficient of variation of ≤ 2%. To estimate the diagnostic sensitivity of the tests, skin biopsies and scrapings from the mucous membrane of the vestibulum vaginae (vaginal scrapings) were taken from cattle with clinical signs of chronic besnoitiosis. Regardless of the real time PCR assay used, 90.7% (39/43) of these animals were positive in at least one of two samples (skin or vaginal scrapings). Antibody titers, as determined by an immunofluorescent antibody test, and the threshold cycle values of the real time PCR obtained for skin samples and vaginal scrapings, were significantly correlated. The specificity of the PCRs was confirmed using genomic DNA from related parasites, including genomic DNA of Besnoitia spp., Neospora caninum, Toxoplasma gondii, Hammondia hammondi, Hammondia heydorni, Isospora spp., Sarcocystis spp., Eimeria bovis, Cryptosporidium parvum, and Trypanosoma brucei brucei. Since the sequence of the ITS-1 region of B. besnoiti is identical with that of Besnoitia species isolated from donkeys (Besnoitia bennetti), and reindeer (Besnoitia tarandi), both real time PCRs detected also DNA of these parasites. One of the B. besnoiti real time PCRs, BbRT1, but not BbRT2, cross-reacted with Besnoitia darlingi, Besnoitia oryctofelisi, and Besnoitia neotomofelis when large amounts of genomic DNA (10 ng) were used. The other B. besnoiti real time PCR assay (BbRT2) was specific for B. besnoiti, B. bennetti and B. tarandi, but did not react when 10 ng DNA of other related parasite species from the genus Besnoitia or other genera were subjected to analysis.
Bovine besnoitiosis is a protozoal disease of cattle which results in severe skin disease in heavily infected animals. The disease is caused by the cyst-forming coccidian parasite Besnoitia besnoiti and was recently classified by the European Food Safety Authority (EFSA) as an emerging disease in Europe.
Bovine besnoitiosis is an economically important disease in cattle caused by the protozoan parasite Besnoitia besnoiti, which occurs endemically in many countries of Africa and Asia and is spreading in Europe. Serological identification of subclinically infected cattle is important to avoid the introduction of infected animals into naive herds. Here we determine the sensitivity and specificity of the PrioCHECK® Besnoitia Ab, a serological test recently introduced into the European market. Analytical specificity was examined using sera from animals experimentally infected with parasites related to B. besnoiti (n=27). Three animals experimentally infected with Neospora caninum or Toxoplasma gondii showed inconclusive reactions in the ELISA (percent positivity relative to the positive control [PP] 10%≤20%) while all other sera reacted negative (PP<10%). An estimate of the diagnostic specificity was obtained by analysing field sera from bovine herds without besnoitiosis but with abortion problems associated to N. caninum (n=403). The analysis revealed a specificity of 94.3% or 96.8% depending on the applied cut-off (PP 10% or 20%, respectively). Sensitivity was assessed with sera from 110 animals of a herd in Germany where clinical bovine besnoitiosis was first diagnosed in September 2008. A positive serological reference standard was defined regarding sera from animals as reference positive, if these animals had tested positive in at least two of a panel of three other serological tests (two different B. besnoiti immunoblots and one immunofluorescence antibody test) on both of two sampling dates, November 2008 and April 2009. A diagnostic sensitivity of 91.8% or 75.5% was determined for sera collected in November 2008 and a sensitivity of 82.7% or 50% for sera collected in April 2009 (cut-off PP 10% or PP 20%, respectively). The marked drop in sensitivity from November 2008 to April 2009 was predominantly observed in reference-positive cattle without clinical signs. We conclude that PrioCHECK® Besnoitia Ab is a valuable diagnostic tool to detect clinically infected animals. Thus it may be used to support control measures, e.g., for the separation of infected animals from the remaining herd to avoid a further transmission of the infection within the herd.
An outbreak of bovine besnoitiosis in Germany; pathomorphological, ultrastructural and molecular-biological investigationsIntroductionBovine besnoitiosis is caused by Besnoitia besnoiti, an obligate intracellular apicomplexan protozoan parasite, which has been reported from different countries of Africa and Asia as well as from France, Spain, and Portugal. The disease is of high economic importance. This paper reports on the first outbreak of bovine besnoitiosis in Germany.Case reportA 3.4 year-old Charolais cow with unusual skin lesions was admitted to the Clinic for Ruminants of the Ludwig-Maximilians-University in Munich. The animal came from a cow-calf-operation with 214 animals. The skin lesions were distributed mostly all over the body, and consisted of multifocal hypotrichosis, alopecia, lichenification, erythema, and seborrhea. Because of a poor prognosis, the animal was euthanized.Post mortem examination of the animal revealed a marked generalised hyperplasia of peripheral lymph nodes and a severe generalised thickening of the skin (up to 2 cm). Cutaneous changes were most evident around the eyes and at the muzzle, teats and extremities. Additionally, multiple disseminated miliary nodules were present bilaterally in the mucosal membranes of the conchae and the vestibulum vaginae. Skin biopsies were taken from further 53 cattle of the same livestock with suspicion of dermal lesions. For histopathological examination and transmission electron microscopy tissue samples were routinely fixed, embedded, and stained according to standard protocols.Histopathologic findings revealed characteristic cysts of Besnoitia spp. in the skin of the muzzle, eye lids, neck, thorax, teats, tail, extremities and the pelvic region as well as in several organs e.g. conchae, tendons, tonsils, eye lids, septum nasale, vestibulum vaginae and in synovial membranes.The cysts were approximately 250 to 300 pm in diameter, circular in cross section, and were surrounded by a moderate to severe chronic granulomatous inflammation. The cyst wall (up to 20 pm) was composed of a prominent outer hyaline layer, a middle layer consisting of a multinucleated host cell, and a thin inner membrane which enclosed the parasitophorous vacuole. The vacuole contained numerous fusiform bradyzoites measuring from 7 x 2 pm to 8 x 2 pm. Transmission electron microscopy of Besnoitia besnoiti bradyzoites revealed typical apicomplexan structures like a conoid, polar ring, 22 microtubules and several rhoptries. The diagnosis was confirmed by serological examination and the species Besnoitia besnoiti was identified by polymerase chain reaction.DiscussionThe pathogenesis, life cycle, and route of infection of B. besnoiti are poorly understood. The presented case indicates that besnoitiosis crossed a further frontier. It is actually unclear, if the disease has been spread within Germany. Due to an increasing awareness of besnoitiosis in Germany, further cases will possibly be detected in future.
Besnoitia besnoiti, an apicomplexan parasite causes economically important disease in cattle in many countries of Africa and Asia is re-emerging in Europe. Serological identification of infected cattle is important because introduction of these animals into naive herds seems to play a major role in the transmission of the parasite. We report new, simplified immunoblot-based serological tests for the detection of B. besnoiti-specific antibodies. Antigens were used under non-reducing conditions in the immunoblots, because reduction of the antigen with β-mercaptoethanol diminished the antigenicity in both, tachyzoites and bradyzoites. Ten B. besnoiti tachyzoite and ten bradyzoite antigens of 15–45 kDa molecular weight were recognized by B. besnoiti infected cattle, but not or only weakly detected by cattle infected with related protozoan parasites, Neospora caninum, Toxoplasma gondii, Sarcocystis cruzi, Sarcocystis hominis, or Sarcocystis hirsuta. The sensitivity and specificity of B. besnoiti immunoblots were determined with sera from 62 German cattle with clinically confirmed besnoitiosis and 404 sera from unexposed German cattle including 214 sera from animals with a N. caninum-specific antibody response. Using a new scoring system, the highest specificity (100%) and sensitivity (90%) of the immunoblots were observed when reactivity to at least four of the ten selected tachyzoite or bradyzoite antigens was considered as positive. When a cut-off based on this scoring system was applied to both the tachyzoite- and the bradyzoite-based immunoblots, there was an almost perfect agreement with the indirect fluorescent antibody test with a titre of 200 as the positive cut-off. We identified and partially characterized 10 tachyzoite and 10 bradyzoite B. besnoiti antigens which may help to develop new specific and sensitive serological tests based on individual antigens and in the identification of possible vaccine candidates.
Besnoitia besnoiti was in vitro isolated during the first recorded outbreak of bovine besnoitiosis in Germany. Molecular characterization of the new isolate, named Bb-GER1, revealed almost 100% identity with other B. besnoiti isolates obtained in Portugal, Spain, Israel or South Africa, when partial sequences of the 18S ribosomal RNA gene, of the internal transcribed spacer 1 and of the 5.8S RNA gene were compared. Cystozoites obtained from skin tissue of one bull were infectious for gamma-interferon knockout (GKO) mice by intraperitoneal (ip) inoculation. Tachyzoites were detected in the peritoneal cavity, spleen, liver and lung of the mice 5 days post-infection. The parasite could be maintained in GKO mice by ip inoculation for at least 5 passages. Peritoneal washings containing tachyzoites were obtained from infected mice and used to infect five cell lines (Vero, MARC-145, NA42/13, BHK(21), KH-R). The best growth of tachyzoites was observed in BHK(21) cells, but replication occurred to a smaller extent also in MARC-145, NA42/13 and KH-R cells. Subsequent comparative analyses revealed that after direct infection of these cell lines with cystozoites derived from bovine skin, the growth was best in NA42/13 cells. Considerable replication was also observed in the BHK(21) and KH-R cell lines. Our observations on the growth characteristics of Bb-GER1 partially contrast those for other isolates. The preferential growth in particular cell lines may be characteristic for particular B. besnoiti isolates. A potential association between growth properties and differences in virulence remains to be established. This is the first in vitro isolation of B. besnoiti from cattle in Germany.