Breed and site predispositions of dogs with atopic dermatitis: a comparison of five locations in three continents.

The objectives of this multicentre study were to analyse and compare breed predispositions and lesion distributions of 552 dogs diagnosed with atopic dermatitis from five different dermatologic referral centres located in Australia, Germany (2) and the United States (2). Breeds were compared with the canine population in the respective locations. Breed predispositions varied from geographical site, although golden retrievers and German shepherd dogs were predisposed in three of five practices. Lesions were present most commonly on the paws (62%), ventrum (51%), ears (48%) and face (39%). Various breeds had specific site predilections. Based on this study, breed predispositions can vary greatly both between continents and also between different locations on the same continent. In addition, some breeds showed predispositions for certain body sites which also varied in some instances with the geographical location.

An immunohistochemical and polymerase chain reaction evaluation of feline plasmacytic pododermatitis.

Sections of 14 skin biopsies of cats with plasmacytic pododermatitis and a clinical follow-up of 12-36 months were stained with a polyclonal anti-Mycobacterium bovis (Bacille Calmette-Guerin = BCG) antibody cross-reactive to a broad spectrum of fungi and bacteria. All sections were negative for organisms within the actual footpad tissue with the anti-BCG antibody stains. Polymerase chain reaction (PCR) assays that amplify the DNA of Bartonella spp., Ehrlichia spp., Anaplasma phagocytophilum, Chlamydophila felis, Mycoplasma spp., Toxoplasma gondii, and feline herpesvirus 1 (FHV-1) were applied to tissue digests. DNA of those pathogens assessed was not amplified from tissue.

Results of allergen-specific immunotherapy in 117 dogs with atopic dermatitis.

The success of the treatment of 117 dogs with atopic dermatitis with allergen-specific immunotherapy for up to 48 months was assessed. An excellent response (remission with exclusive immunotherapy) was recorded in 18 of the dogs, a good response (more than 50 per cent reduction in medication and improvement of clinical signs) was recorded in 57, a moderate response was recorded in 24 and a poor response in 18. The mould antigens in the allergen extract were stored in a separate vial before administration and the success rate of the immunotherapy including mould antigens was much higher than in an earlier study in which mould and pollen antigens had been stored in one vial. The success rate was not affected significantly by the age of the dogs when the disease developed, or by their age or the period for which they had shown clinical signs when the treatment began; it was also unaffected by whether pollens, moulds or dust mites were used as antigens, or by whether the offending allergens had been identified by intradermal testing or by serum testing for allergen-specific immunoglobulin E.

Review of 15 cases of pemphigus foliaceus in horses and a survey of the literature.

The records of 15 horses with pemphigus foliaceus diagnosed on the basis of their history, clinical signs, histopathology and the exclusion of differential diagnoses were evaluated with respect to the age of onset, the clinical signs and the diagnostic tests used. There was no apparent breed predisposition. The horses' mean age was nine years, with a range from three months to 25.5 years, three were foals up to six months old and eight were nine years old or older. The most frequent lesions were scaling in 11, crusting in 10 and alopecia in 10, and they appeared most commonly on the face, neck and trunk, in 10 horses for each of these sites. The extremities were involved in nine of the horses, pruritus occurred in seven, and four of the horses had pustules. The clinical signs mostly corresponded with those described in previous reports, but signs of pain were not a prominent feature. Acantholytic cells were identified cytologically in four of six of the horses.

Immunohistochemical evaluation of mononuclear infiltrates in canine lupoid onychodystrophy.

Claw biopsy samples of 11 dogs with lupoid onychodystrophy were evaluated. They were stained with hematoxylin and eosin and with antibodies against CD 3 as a T-cell marker, BLA 36 and HM 57 (CD 79alpha) as B-cell markers, and lysozyme, Mac 387, and major histocompatibility complex (MHC) class II as a marker for histiocytes using an immunoperoxidase and avidin-biotin technique. Inflammatory cells were counted in five high-power fields. The inflammatory infiltrate comprised predominantly B cells and T cells. Macrophages were typically only present in small numbers. CD 3, BLA 36, lysozyme, and MHC class II preserved significant antigenicity during formalin fixation and short decalcification for 24-48 hours, whereas CD 79alpha and particularly Mac 387 seemed to be more susceptible to denaturation by the decalcification process.

Value of the pinnal-pedal reflex in the diagnosis of canine scabies.

The potential value of the pinnal-pedal scratch reflex as an aid to diagnosing canine scabies was assessed in 588 dogs with skin disease. The reflex was assessed by vigorously rubbing the tip of one earflap on to the base of the ear for five seconds, and it was considered positive if the ipsilateral hind leg made a scratching movement. A diagnosis of scabies was based on the dog's history, a physical examination and either positive skin scrapings or the complete resolution of pruritus and dermatitis after treatment with ivermectin or milbemycin, with no relapse for at least 12 months. Scabies was diagnosed in 55 of the dogs, allergic skin disease in 463, and 70 had other miscellaneous skin diseases. There was a positive pinnal-pedal scratch reflex in 45 (82 per cent) of the 55 dogs with scabies. Forty (73 per cent) of the dogs with scabies had pinnal dermatitis, and 36 (90 per cent) of these had a positive pinnal-pedal scratch reflex. There was a positive pinnal-pedal scratch reflex in 33 (6.2 per cent) of the other 533 dogs. On the basis of these results, the specificity of testing for scabies by the pinnal-pedal scratch reflex was 93.8 per cent, and the sensitivity was 81.8 per cent The test's positive predictive value was 0.57 and its negative predictive value was 0.98.

Evaluation of the safety of an abbreviated course of injections of allergen extracts (rush immunotherapy) for the treatment of dogs with atopic dermatitis.

OBJECTIVE: To evaluate the safety of an abbreviated course of injections of allergen extracts (rush immunotherapy) for the treatment of dogs with atopic dermatitis. ANIMALS: 30 dogs with atopic dermatitis examined at a veterinary dermatology referral practice for treatment with allergen-specific immunotherapy. PROCEDURE: A catheter was placed in a vein in each dog. Dogs were constantly observed throughout the procedure. Allergen extracts were administered in increasing concentrations every 30 minutes for 6 hours to a maintenance concentration of 20,000 protein nitrogen units/ml. Epinephrine, oxygen, and emergency treatment were available as needed. RESULTS: In 22 (73%) dogs, rush immunotherapy safely replaced the prolonged induction period (15 weeks) of weekly injections that consists of increasing concentrations of allergen extract. In 7 (23%) dogs, the induction period was abbreviated to 4 weeks. Of the 8 dogs that developed problems during rush immunotherapy, increased pruritus necessitated premature cessation of rush immunotherapy in 7, and 1 developed generalized wheals. Oral administration of prednisolone (1 mg/kg of body weight) resulted in resolution of adverse effects in all 8 dogs. CONCLUSION AND CLINICAL RELEVANCE: Rush immunotherapy performed by personnel at a veterinary hospital is a safe method for treatment of dogs with atopic dermatitis.

Aero-allergens in canine atopic dermatitis in southeastern Australia based on 1000 intradermal skin tests.

OBJECTIVE: To determine the most relevant aero-allergens involved in canine atopic dermatitis in southeastern Australia and provide information about these aero-allergens to the general practitioner. PROCEDURE: Dogs presented to the Animal Skin & Allergy Clinic with history and clinical signs of atopic dermatitis were injected intradermally with 38 different allergens and negative and positive control. Intradermal skin tests in 1000 dogs were retrospectively evaluated. RESULTS: One third of all patients reacted to the house dust mite Dermatophagoides farinae. Allergens reacting in more than 15% of the patients were wheat (Triticum aestivum), sweet vernal (Anthoxanthum odoratum), English couch (Agropyron repens), yellow dock (Rumex crispus), Mexican tea (Chenopodium ambrosioides), plantain (Plantago lanceolata), melaleuca (Melaleuca quinquenervia) and peppercorn (Schimus spp). CONCLUSION: House dust mites are the most common allergens in canine atopic dermatitis in southeastern Australia and D farinae is involved most frequently. However, a number of grass, weed and tree pollens also are involved regularly.

A proposed new therapeutic protocol for the treatment of canine mange with ivermectin.

Ivermectin was used orally for the treatment of generalized demodicosis or scabies in 222 dogs. The dose was increased gradually from 50 microg/kg body weight on day one, 100 microg/kg body weight on day two, 150 microg/kg body weight on day three, 200 microg/kg body weight on day four, to the final dose of 300 microg/kg body weight on day five. This dose was continued daily until resolution for demodicosis and given four times at seven-day intervals for scabies. Two patients developed clinical ivermectin toxicity after two and 10 days, respectively, and recovered once the drug was discontinued. A gradual increase of the ivermectin dose into the therapeutic range and thorough monitoring of patients during treatment are recommended when using this drug to treat patients with generalized demodicosis or scabies.