Testing for food-specific antibodies in saliva and blood of food allergic and healthy dogs.

An elimination diet (ED) followed by re-challenge has been the reference standard to diagnose adverse food reactions (AFR) in dogs, but can be challenging to conduct. This study investigated the accuracy of a saliva-based test for food-specific IgA and IgM and an ELISA serum test for food-specific IgE. Three groups of dogs were tested. Group 1 (n=11) included dogs with previously diagnosed and controlled AFR; group 2 (n=15) comprised dogs with allergic dermatitis at the beginning of their ED; and group 3 (n=16) was composed of clinically healthy research dogs. Saliva samples were collected from all groups and blood samples from group 1 and group 3. The results of clinical re-challenges with individual food components were compared with the test results. Specificity, sensitivity, positive and negative predictive values and likelihood ratios were determined. Forty-one dogs completed the study; one dog was lost to follow up. There was a total of 163 re-challenges. Sensitivity, positive predictive value and likelihood ratio, specificity, negative predictive value and likelihood ratios were unsatisfactory for both tests in most instances, except for IgM testing in group 2, which had moderate specificity. There was no clear difference in the number of positive reactions between the allergic dogs and healthy dogs from a research population. Based on these results, the saliva test for food specific IgA and IgM and the ELISA serum test for food specific IgE were not reliable to diagnose adverse food reactions in dogs. Until more data are available, elimination diets remain the reference standard in the diagnosis of this disease.

Adverse food reactions: Pathogenesis, clinical signs, diagnosis and alternatives to elimination diets.

This review summarises available information about adverse food reactions in dogs and cats. Much of the published information on the pathogenesis of adverse food reactions in these species is transferred from what is known in mice and human beings. Clinical signs affect mostly the integument and gastrointestinal system. Pruritus of the distal limbs, face, ears and ventrum is the most common cutaneous presentation in dogs, although urticaria has also been reported. In cats, all so-called 'cutaneous reaction patterns' may be due to adverse food reactions. The most common gastrointestinal signs in both species are diarrhoea and vomiting. An elimination diet over several weeks using a protein source and a carbohydrate source previously not fed is still the diagnostic tool of choice. Improvement on such a diet, deterioration on re-challenge with the old food and improvement again on the elimination diet confirms the diagnosis of adverse food reaction, whereas alternative tests of blood, serum, saliva and hair have been found to be unsatisfactory. Patch testing with food antigens has been recommended as an aid to choose the elimination diet ingredients, since it has a reasonable negative predictability and likelihood ratio, but is laborious and costly.

Allergen immunotherapy in people, dogs, cats and horses - differences, similarities and research needs.

In human patients with seasonal allergic rhinoconjunctivitis sensitized to grass pollen, the first successful allergen immunotherapy (AIT) was reported in 1911. Today, immunotherapy is an accepted treatment for allergic asthma, allergic rhinitis and hypersensitivities to insect venom. AIT is also used for atopic dermatitis and recently for food allergy. Subcutaneous, epicutaneous, intralymphatic, oral and sublingual protocols of AIT exist. In animals, most data are available in dogs where subcutaneous AIT is an accepted treatment for atopic dermatitis. Initiating a regulatory response and a production of "blocking" IgG antibodies with AIT are similar mechanisms in human beings and dogs with allergic diseases. Although subcutaneous immunotherapy is used for atopic dermatitis in cats, data for its efficacy are sparse. There is some evidence for successful treatment of feline asthma with AIT. In horses, most studies evaluate the effect of AIT on insect hypersensitivity with conflicting results although promising pilot studies have demonstrated the prophylaxis of insect hypersensitivity with recombinant antigens of biting midges (Culicoides spp.). Optimizing AIT using allergoids, peptide immunotherapy, recombinant allergens and new adjuvants with the different administration types of allergen extracts will further improve compliance and efficacy of this proven treatment modality.

Preliminary evaluation of cytosine-phosphate-guanine oligodeoxynucleotides bound to gelatine nanoparticles as immunotherapy for canine atopic dermatitis.

Cytosine-phosphate-guanine oligodeoxynucleotides (CpG ODN) are a promising new immunotherapeutic treatment option for canine atopic dermatitis (AD). The aim of this uncontrolled pilot study was to evaluate clinical and immunological effects of gelatine nanoparticle (GNP)-bound CpG ODN (CpG GNP) on atopic dogs. Eighteen dogs with AD were treated for 8 weeks (group 1, n=8) or 18 weeks (group 2, n=10). Before inclusion and after 2 weeks, 4 weeks, 6 weeks (group 1+2), 8 weeks, 12 weeks and 16 weeks (group 2) 75 µg CpG ODN/dog (bound to 1.5 mg GNP) were injected subcutaneously. Pruritus was evaluated daily by the owner. Lesions were evaluated and serum concentrations and mRNA expressions of interferon-γ, tumour necrosis factor-α, transforming growth factor-ß, interleukin (IL) 10 and IL-4 (only mRNA expression) were determined at inclusion and after 8 weeks (group 1+2) and 18 weeks (group 2). Lesions and pruritus improved significantly from baseline to week 8. Mean improvements from baseline to week 18 were 23 per cent and 44 per cent for lesions and pruritus, respectively, an improvement of ≥50 per cent was seen in six out of nine and three out of six dogs, respectively. IL-4 mRNA expression decreased significantly. The results of this study show a clinical improvement of canine AD with CpG GNP comparable to allergen immunotherapy. Controlled studies are needed to confirm these findings.

Comparing immediate-type food allergy in humans and companion animals-revealing unmet needs.

Adverse food reactions occur in human as well as veterinary patients. Systematic comparison may lead to improved recommendations for prevention and treatment in both. In this position paper, we summarize the current knowledge on immediate-type food allergy vs other food adverse reactions in companion animals, and compare this to the human situation. While the prevalence of food allergy in humans has been well studied for some allergens, this remains to be investigated for animal patients, where owner-reported as well as veterinarian-diagnosed food adverse reactions are on the increase. The characteristics of the disease in humans vs dogs, cats, and horses are most often caused by similar, but sometimes species-dependent different pathophysiological mechanisms, prompting the specific clinical symptoms, diagnoses, and treatments. Furthermore, little is known about the allergen molecules causative for type I food allergy in animals, which, like in human patients, could represent predictive biomarkers for risk evaluation. The definite diagnosis of food allergy relies-as in humans-on elimination diet and provocation tests. Besides allergen avoidance in daily practice, novel treatment options and tolerization strategies are underway. Taken together, numerous knowledge gaps were identified in veterinary food allergy, which need to be filled by systematic comparative studies.

Role of canine circovirus in dogs with acute haemorrhagic diarrhoea.

Canine circovirus (CanineCV) has been detected in some dogs with severe haemorrhagic diarrhoea, but its pathogenic role is unclear. This study evaluated a suspected association between the presence of CanineCV and acute haemorrhagic diarrhoea syndrome (AHDS) in dogs. The prevalence of CanineCV in dogs with AHDS was compared with that in healthy dogs and those infected with canine parvovirus (CPV). Additionally, time to recovery and mortality rate were compared between CanineCV-positive and CanineCV-negative dogs. Faecal samples of dogs with AHDS (n=55), healthy dogs (n=66) and dogs infected with CPV (n=54) were examined by two real-time TaqMan PCR assays targeting the replicase and capsid genes of CanineCV. CanineCV was detected in faecal samples of two dogs with AHDS, three healthy controls and seven dogs infected with CPV. Among the three groups, there was no significant difference in prevalence of CanineCV. CPV-infected animals that were coinfected with CanineCV had a significantly higher mortality rate compared with those negative for CanineCV. CanineCV does not appear to be the primary causative agent of AHDS in dogs, but might play a role as a negative co-factor in disease outcome in dogs with CPV infection.

Comparison of ultrasound imaging and video otoscopy with cross-sectional imaging for the diagnosis of canine otitis media.

Ultrasound imaging (US) of the tympanic bulla (TB) for diagnosis of canine otitis media (OM) is less expensive and less invasive than cross-sectional imaging techniques including computed tomography (CT) and magnetic resonance imaging (MRI). Video otoscopy (VO) is used to clean inflamed ears. The objective of this study was to investigate the diagnostic value of US and VO in OM using cross-sectional imaging as the reference standard. Client owned dogs with clinical signs of OE and/or OM were recruited for the study. Physical, neurological, otoscopic and otic cytological examinations were performed on each dog and both TB were evaluated using US with an 8 MHz micro convex probe, cross-sectional imaging (CT or MRI) and VO. Of 32 dogs enrolled, 24 had chronic otitis externa (OE; five also had clinical signs of OM), four had acute OE without clinical signs of OM, and four had OM without OE. Ultrasound imaging was positive in three of 14 ears, with OM identified on cross-sectional imaging. One US was false positive. Sensitivity, specificity, positive and negative predictive values and accuracy of US were 21%, 98%, 75%, 81% and 81%, respectively. The corresponding values of VO were 91%, 98%, 91%, 98% and 97%, respectively. Video otoscopy could not identify OM in one case, while in another case, although the tympanum was ruptured, the CT was negative. Ultrasound imaging should not replace cross-sectional imaging for the diagnosis of canine OM, but can be helpful, and VO was much more reliable than US.

Evaluation of cyclosporine-sparing effects of polyunsaturated fatty acids in the treatment of canine atopic dermatitis.

A randomised, double-blinded, placebo-controlled multicentre trial was conducted in 36 dogs with atopic dermatitis to evaluate the cyclosporine-sparing effect of polyunsaturated fatty acids. Dogs were stable on their individual cyclosporine dosage and received either a mainly omega-3 fatty acid product with a minor omega-6 fatty acid fraction or placebo, orally for 12 weeks. Dogs were examined every 4 weeks and the Canine Atopic Dermatitis Extent and Severity Index (CADESI-03) was determined by a clinician. Pruritus, quality of life, global condition and coat quality were scored by the owner. If the dog's CADESI-03 and/or pruritus score improved by at least 25% compared with the previous visit, the cyclosporine dosage was decreased by approximately 25%. If the scores deteriorated by at least 25%, the cyclosporine dosage was increased by the same percentage. The median daily cyclosporine dosage/kg bodyweight decreased in the active group from 4.1 mg to 2.6 mg and in the placebo group from 3.5 mg to 3.3 mg over the study period. The difference between the two groups was significant (P = 0.009). The improvement in median pruritus score from inclusion to completion was significantly greater in the active group than in the placebo group (P = 0.04). There was no significant difference in CADESI-03 changes between groups (P = 0.38). The results of this study indicate a cyclosporine-sparing effect of a mainly omega-3 fatty acid supplement in dogs with atopic dermatitis.

Allergens in veterinary medicine.

Allergic diseases in animals are increasingly gaining importance in veterinary practice and as research models. For intradermal testing and allergen immunotherapy, a good knowledge of relevant allergens for the individual species is of great importance. Currently, the knowledge about relevant veterinary allergens is based on sensitization rates identified by intradermal testing or serum testing for allergen-specific IgE; crude extracts are the basis for most evaluations. Only a few studies provide evidence about the molecular structure of (particularly) dust mite, insect and mould allergens in dogs and horses, respectively. In those species, some major allergens differ from those in humans. This position paper summarizes the current knowledge about relevant allergens in dogs, cats and horses.

Clinical Research Abstracts of the British Equine Veterinary Association Congress 2015.

REASONS FOR PERFORMING STUDY: New therapeutic strategies to modulate immune responses in human and equine allergic airway diseases are under extensive investigation. Stimulation of Treg cells with immune modulating agents is a novel therapeutic option. OBJECTIVES: The aim of this field study was to compare the effects of a nebulised nanoparticulate CpG immunotherapy (CpG-GNP) with and without specific allergens. STUDY DESIGN: Longitudinal clinical study comparing 2 therapeutic options. METHODS: Twenty RAO-affected horses were divided into 2 treatment groups (CpG alone and CpG with allergens). Two specific allergens were selected for each horse according to anamnesis and a functional in vitro test. Treatments were given by nebulisation 7 times and the horses were examined 3 times: baseline (I), after the treatment course (II), and after 6 weeks later (III). Clinical parameters, indirect intrapleural measurement, arterial blood gas, amount of tracheal mucus and neutrophil percentage were evaluated. RESULTS: CpG alone resulted in a significant improvement in clinical parameters and a significant reduction of tracheal mucus after treatment and at 6 weeks post treatment. After CpG plus specific allergens, there was significant improvement of 70% of examined parameters. However, there were no significant differences in the results compared with CpG-GNP treatment alone. CONCLUSIONS: There were no significant differences between treatment groups. CpG-GNP immunotherapy alone produced a potent and persistent effect on allergic and inflammatory parameters and may have potential as for treatment of equine and human allergic inflammatory airway diseases. Ethical animal research: The study was approved by the regional legal agency for animal experiments of the Government of Bavaria, Germany (No. 55.2-1-54-2531-31-10). Owners gave informed consent for their horses' inclusion in the study. Sources of funding: Partly supported by the Deutsche Forschungsgemeinschaft (DFG) (Germany) (GE'2044/4-1). The AeroNeb Go™ vibrating mesh nebuliser (Aerogen, Galway, Ireland) was sponsored by Inspiration Medical (Bochum, Germany). Competing interests: None declared.

Neurogenic inflammation and colliquative lymphadenitis with persistent orthopox virus DNA detection in a human case of cowpox virus infection transmitted by a domestic cat.

Cowpox viruses are orthopoxviruses that may survive in the environment for years. Rodents are regarded as the primary hosts, but transmission to other species has been reported. This report describes a cowpox virus infection in a cat with subsequent transmission to its owner leading to protracted, atypical and severe clinical signs. A young cat presented with multiple crusts and plaques on the neck, muzzle and tail base. The owner developed an erythematous lesion with elevated margins, central necrosis and crust formation below the left breast, a neurogenic inflammation, enlarged regional lymph nodes, a colliquative lymphadenitis and concomitant flu-like symptoms. Cultures were taken at the first visit from the cat's lesional skin and the patient's skin, and polymerase chain reaction with sequencing of the haemagglutinin region of both were positive for cowpox virus. The patient was treated with various antibiotics and methylprednisolone and was in clinical remission after 7 months.

Prospective study of bacteraemia in acute haemorrhagic diarrhoea syndrome in dogs.

In dogs with idiopathic acute haemorrhagic diarrhoea syndrome (AHDS), a serious loss of intestinal mucosal barrier integrity occurs. However, the incidence of bacterial translocation in dogs with idiopathic AHDS is not known. Thus, the objectives of this prospective study were to identify the incidence of bacteraemia, to evaluate the frequency of septic events and the influence of bacteraemia on various clinical and laboratory parameters, duration of hospitalisation and survival of dogs with idiopathic AHDS. The study included 87 dogs with idiopathic AHDS. Twenty-one healthy dogs served as control group. To evaluate clinical significance of bacterial translocation, blood culture results were compared between patients and controls. Clinical and laboratory parameters were compared between patients with positive and negative blood cultures. There was no significant difference in either incidence of bacteraemia between patients with idiopathic AHDS (11 per cent) and controls (14 per cent) or in severity of clinical signs, laboratory parameters, duration of hospitalisation or mortality between blood culture-positive and culture-negative dogs with idiopathic AHDS. The results of this study suggest that the incidence of bacteraemia in dogs with idiopathic AHDS is low and not different from that of healthy control dogs. Bacteraemia does not influence the clinical course or survival and thus antibiotic treatment is not indicated to prevent sepsis.

Clostridium perfringens enterotoxin and Clostridium difficile toxin A/B do not play a role in acute haemorrhagic diarrhoea syndrome in dogs.

Although an association between clostridial pathogens and canine idiopathic acute haemorrhagic diarrhoea syndrome (AHDS) has been described, the relevance of those bacteria and their toxins remains unclear. The aim of this study was to evaluate the association between severity of clinical signs and presence of Clostridium perfringens enterotoxin (CPE) and Clostridium difficile toxin A/B (CDT A/B) in faeces of dogs with AHDS. Faecal samples of 54 dogs with idiopathic AHDS were tested by qualitative CPE and CDT A/B ELISA, and PCR was performed to detect enterotoxin genes of C. perfringens (cpe) and toxin B genes of C. difficile (cdt b). Prevalence of cdt b and CDT A/B in dogs with AHDS was 10/54 and 2/54 versus 3/23 and 0/23 in control dogs. Prevalence of cpe was 35/54 in affected versus 9/23 in control dogs. Prevalence of CPE in dogs with AHDS (13/54) was higher compared with control dogs (0/23). No significant difference was detected between CPE-positive and -negative and between cpe-positive and -negative dogs in severity of clinical signs, duration of hospitalisation, mortality rate and selected laboratory parameters. This study suggests that CPE and CDT A/B do not play a role in idiopathic AHDS, are not associated with clinical parameters in affected dogs and cannot be used to predict disease outcome.

Efficacy and safety of rush immunotherapy with alum-precipitated allergens in canine atopic dermatitis.

OBJECTIVES: Canine atopic dermatitis is a very common disease in small animal practice. Its only specific treatment is allergen immunotherapy. In rush-immunotherapy (RIT) increasing doses of allergen extract are injected subcutaneously in short intervals. Maintenance doses are achieved within one day compared to weeks or months with conventional immunotherapy. The aim of this study was to evaluate the safety and efficacy of RIT with alum-precipitated allergens. MATERIALS AND METHODS: A series of 20 dogs with atopic dermatitis underwent RIT with alum-precipitated allergens. Pruritus and medications at the start of the immunotherapy and 12 months afterwards were compared and adverse effects were recorded. RESULTS: Significant improvement in pruritus (p = 0.0001) and medication scores (p = 0.0004) was noted after approximately 12 months of treatment. The observed clinical response was good to excellent in 70% of the dogs, consistent with other published reports. One dog vomited once during the induction day, with no other clinical problems and completion of the normal protocol. The other 19 dogs showed no adverse effects at all during or after RIT. CONCLUSION AND CLINICAL RELEVANCE: RIT with alum-precipitated allergens seems to be a safe and efficacious method to treat dogs with atopic dermatitis.

Endoscopically visualized lesions, histologic findings, and bacterial invasion in the gastrointestinal mucosa of dogs with acute hemorrhagic diarrhea syndrome.

BACKGROUND: Etiology of hemorrhagic gastroenteritis (HGE) syndrome in dogs is unknown and histopathologic and microbial investigations have only been performed post mortem. OBJECTIVE: To identify characteristic intra vitam endoscopic and histologic mucosal lesions, as well as bacterial species, within the mucosa of dogs with HGE. ANIMALS: Ten dogs diagnosed with HGE were included. Eleven dogs with gastroduodenoscopy and different intestinal diseases were used as controls for microbial changes. Dogs pretreated with antibiotics or diagnosed with any disease known to cause bloody diarrhea were excluded from the study. METHODS: In this prospective study, gastrointestinal biopsies were collected from 10 dogs with HGE. Endoscopic and histologic changes were assessed according to WSAVA guidelines. Biopsies from the stomach, duodenum, ileum, and colon were investigated by histology and by immunohistochemistry for the presence of Clostridium spp. and parvovirus. The first duodenal biopsy taken with a sterile forceps was submitted for bacterial culture. RESULTS: Acute mucosal lesions were only found in the intestines, not in the stomach. Clostridium spp., identified as Clostridium perfringens in 6/9 cases, were detected on the small intestinal mucosa in all dogs with HGE, either by culture or immunohistopathology. In the control group, C. perfringens could only be cultured in one of 11 dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: The results of this study demonstrate an apparent association between C. perfringens and the occurrence of acute hemorrhagic diarrhea. The term "HGE," which implies the involvement of the stomach, should be renamed as "acute hemorrhagic diarrhea syndrome."

Clinical characterization of epilepsy of unknown cause in cats.

BACKGROUND: The diagnosis of feline epilepsy of unknown cause (EUC) requires a thorough diagnostic evaluation, otherwise the prevalence of EUC could be overestimated. HYPOTHESIS: Feline EUC is a clinically defined disease entity, which differs from feline hippocampal necrosis by the absence of magnetic resonance imaging (MRI) signal alteration of the hippocampus. The objectives of this study were (1) to evaluate the prevalence of EUC in a hospital population of cats by applying well-defined inclusion criteria, and (2) to describe the clinical course of EUC. ANIMALS: Eighty-one cats with recurrent seizures. METHODS: Retrospective study--medical records were reviewed for cats presented for evaluation of recurrent seizures (2005-2010). Inclusion criteria were a defined diagnosis based on laboratory data, and either MRI or histopathology. Final outcome was confirmed by telephone interview with the owner. Magnetic resonance images were reviewed to evaluate hippocampal morphology and signal alterations. RESULTS: Epilepsy of unknown cause was diagnosed in 22% of cats with epilepsy. Physical, neurologic, and laboratory examinations, and either 1.5 T MRI and cerebrospinal fluid analysis or postmortem examination failed to identify an underlying cause. Cats with EUC had a higher survival rate (P < .05) and seizure remission occurred frequently (44.4%). CONCLUSION AND CLINICAL IMPORTANCE: A detailed clinical evaluation and diagnostic imaging with MRI is recommended in any cat with recurrent seizures. The prognosis of cats with normal MRI findings and a clinical diagnosis of EUC are good. Standardized imaging guidelines should be established to assess the hippocampus in cats.

The effect of a spot-on formulation containing polyunsaturated fatty acids and essential oils on dogs with atopic dermatitis.

Recent studies have shown that immunological aberrations and epidermal barrier defects could be important in the pathogenesis of canine atopic dermatitis (CAD) and that oral polyunsaturated fatty acids (PUFAs) might influence the epidermal barrier. The aim of this study was to evaluate the effects of a spot-on formulation containing PUFAs and essential oils on pruritus and lesions caused by CAD. Forty-eight privately owned dogs of different breeds, ages and genders diagnosed with atopic dermatitis were included in a randomized, double-blinded, placebo-controlled, multicentre clinical trial. Dogs were treated with a spot-on formulation containing PUFAs and essential oils or placebo on the dorsal neck once weekly for 8weeks. Before and after the study, CAD extent and severity index-03 (CADESI-03) and pruritus scores were determined by veterinarians and owners, respectively. There was significantly more improvement in CADESI-03 and pruritus scores in the treatment group than in the placebo group (P=0.011 and P=0.036, respectively). Additionally, more dogs improved by at least 50% in CADESI-03 and pruritus scores in the treatment group than in the placebo group (P=0.008 and P=0.070, respectively). No adverse reactions were observed. The topical preparation containing PUFAs and essential oils was a safe treatment and beneficial in ameliorating the clinical signs of CAD.

Efficacy of dimetinden and hydroxyzine/chlorpheniramine in atopic dogs: a randomised, controlled, double-blinded trial.

Antihistaminic drugs are commonly used as symptomatic therapy of atopic dermatitis in dogs. Unfortunately, their clinical benefit is largely unsubstantiated. In a double-blinded, placebo-controlled, cross-over trial, the influence of dimetinden and of a combination of chlorpheniramine and hydroxyzine on pruritus and lesions was evaluated in 19 dogs. They were treated with either product or a placebo orally for 14 days, each time followed by a 14-day washout period. Before and after each period, the dogs were examined and the Canine Atopic Dermatitis Extent and Severity Index (CADESI) determined by a clinician, and the pruritus and general condition by the owner. Dimetinden improved the pruritus significantly (P=0.014) but not the CADESI (P=0.087), the combination of hydroxyzine and chlorpheniramine improved the CADESI (P=0.049) and pruritus (P=0.05) significantly. Ten of 17 dogs improved by more than 25 per cent in pruritus with the combination of hydroxyzine and chlorpheniramine, 12 of 18 with dimetindenmaleate and only 2 of 19 with placebo. Antihistamines can help to reduce pruritus in atopic dogs, but in most cases, the improvement is limited and additional treatment may be needed.

[Comparison of four different staining methods for ear cytology of dogs with otitis externa]. / Vergleich von vier zytologischen Färbeverfahren für Ohrabstriche beim Hund.

AIM: Cytological examination is crucial for the diagnosis and classification of canine otitis externa. Staining should reveal micro-organisms as perpetuating factors of otitis externa. The aim of the study was to compare four different staining methods (Diff-Quik®, Diff-Quik® after dipping in acetone, Gram Quick stain® and a commercial rapid stain for otitis externa) for ear cytology of dogs with otitis externa and to investigate the agreement of cytology and culture. MATERIAL AND METHODS: In a study evaluating dogs with otitis externa, five ear swabs (one for culture and four for cytology) were taken from the horizontal part of the external auditory canal of 224 affected ears and compared semi-quantitatively. RESULTS: Diff-Quik® with and without prior dipping in acetone as well as the Gram Quick stain® displayed a high degree of agreement in the detection of micro-organisms (cocci p = 0.2366; rods p = 0.4832; yeasts p = 0.1574), while the commercial otitis rapid stain revealed significantly less micro-organisms (p < 0.001 for all comparisons). The results of the first three stains corresponded to the culture results by >  70%; the agreement was lower with the commercial otitis rapid stain. The quickest and easiest method was staining with Diff-Quik®. CONCLUSION: Diff-Quik® with or without prior dipping in acetone and the Gram Quick stain® had a high agreement in the detection of microorganisms and can thus be considered nearly equivalent for the diagnosis of otitis externa infectiosa. The commercial otitis rapid stain is less reliable. CLINICAL RELEVANCE: Based on this study Diff-Quik® can be recommended for the routine cytology of ear swabs. Additionally, a culture may be indicated and must be interpreted in the context of the cytology.