Clinical and histopathological features of pemphigus foliaceus with and without eosinophilic infiltrates: a retrospective evaluation of 40 dogs

The importance of cellular infiltrates in tissues has been investigated as a diagnostic tool, mechanism of pathogenesis, and prognostic indicator in certain human diseases. Eosinophils, in particular, have a distinct role in the development of cutaneous lesions in human autoimmune diseases. Identification of an eosinophilic infiltrate can aid the diagnosis of immunobullous disease in the early stages of the disease process. In canine pemphigus foliaceus, eosinophils are present to a variable degree within lesional tissue. This study retrospectively evaluated 40 dogs with pemphigus foliaceus, and examined clinical and histologic features and final outcomes in cases with and without eosinophilic infiltrates. Twenty‐five of 40 dogs (63%) had an eosinophilic infiltrate in either the pustules/crust, follicular infundibulum or dermis. There was no statistically significant difference in clinical distribution or appearance of dermatological lesions, response to treatment, or disease outcome in dogs with or without an eosinophilic infiltrate. However, dogs with concurrent disease were significantly more likely to have an eosinophilic infiltrate (P = 0.01). Dogs with adverse effects associated with immunosuppressive therapy were significantly more likely to have an eosinophilic infiltrate (P = 0.05). Fifteen of 40 dogs (38%) had a history of allergic disease and a significantly higher proportion of these dogs had an eosinophilic infiltrate (P = 0.04). An eosinophilic infiltrate was found in more than half of the dogs in this study. These findings justify further studies to investigate the role of eosinophils in the pathogenesis, therapy and prognosis in dogs with pemphigus foliaceus.     

Clinical evaluation of a nutraceutical,carprofen and meloxicam for the treatment of dogs with osteoarthritis

The efficacy, tolerance and ease of administration of a nutraceutical, carprofen or meloxicam were evaluated in a prospective, double-blind study on 71 dogs with osteoarthritis. The client-owned dogs were randomly assigned to one of the three treatments or to a placebo control group. The influence of osteoarthritis on the dogs' gait was described by comparing the ground reaction forces of the arthritic dogs and 10 normal dogs. Before the treatments began, and 30 and 60 days later, measurements were made of haematological and biochemical variables and of the ground reaction forces of the arthritic limb, and subjective assessments were made by the owners and by the orthopaedic surgeons. Changes in the ground reaction forces were specific to the arthritic joint, and were significantly improved by carprofen and meloxicam but not by the nutraceutical; the values returned to normal only with meloxicam. The orthopaedic surgeons assessed that there had been an improvement with carprofen and meloxicam, but the owners considered that there had been an improvement only with meloxicam. The blood and faecal analyses did not reveal any changes. The treatments were well tolerated, except for a case of hepatopathy in a dog treated with carprofen.     

Zonal dermal separation: a distinctive histopathological lesion associated with hyperelastosis cutis in a Quarter Horse

This case report describes a distinctive deep cutaneous lesion in a 1-year-old Quarter Horse filly with hyperelastosis cutis. The horse had a typical clinical presentation of hyperelastic skin associated with a 6-month history of cutaneous wounds that developed following minor cutaneous trauma. Punch biopsies of skin from the affected horse were thinner than similar biopsies from an age- and breed-matched control. Significant microscopic lesions were not seen in cutaneous punch biopsies stained with haematoxylin and eosin and Masson's trichrome stains, but the ultrastructure of the dermis from the affected horse was characterized by variation in collagen fibre diameter and loose packing of collagen fibres within bundles. The horse was euthanized and necropsied, and full-thickness sections of skin were collected and examined microscopically. Affected skin was of normal thickness; however, the deep dermis contained a distinctive horizontal linear zone in which separation of collagen bundles resulted in the formation of large empty cleft-like spaces between the upper and lower regions of the deep dermis. We suggest the term 'zonal dermal separation' for this microscopic lesion. Incisional full-thickness skin biopsies should be taken in suspected cases of equine hyperelastosis cutis because punch biopsies may not obtain enough deep dermis to adequately represent pathological change in the skin of horses with this disorder.     

Efficacy of orbifloxacin tablets for the treatment of superficial and deep pyoderma due to Staphylococcus intermedius infection in dogs

Orbifloxacin tablets were administered orally to 23 dogs with superficial and/or deep staphylococcal pyoderma. Response to therapy was excellent in 95.6% of the dogs. Duration of therapy varied from 21 to 40 days (average 29 days) for dogs having only superficial infections, and from 25 to 150 days (average 72 days) for dogs having deep infections. Relapses occurred in 18% of the dogs within a 3-month period. One dog developed a presumed adverse cutaneous drug reaction. Under the conditions of this study, orbifloxacin was an effective, safe, and convenient antibiotic for the treatment of superficial and deep staphylococcal pyoderma in dogs.     

Identification of rickettsiae in cutaneous biopsy specimens from dogs with experimental Rocky Mountain spotted fever

Direct immunofluorescence reaction for Rickettsia rickettsii was performed on formalin-fixed, paraffin-embedded cutaneous biopsy specimens collected from dogs with experimental Rocky Mountain spotted fever (RMSF). A technique of trypsin digestion of deparaffinized, rehydrated sections was successful in demonstrating discrete, immunofluorescent organisms in endothelia and adjacent vessel walls in the dermis. R rickettsii was identified only in grossly evident dermal lesions (macular rash or oral vesicles) and was not apparent in randomly collected biopsy specimens from clinically normal inguinal skin. These results suggest that clinical application of this technique for diagnosis of RMSF may be limited in dogs without cutaneous lesions.     

Effects of meloxicam on severity of lameness and other clinical signs of osteoarthritis in dogs

OBJECTIVE: To evaluate effects of meloxicam on severity of lameness and other clinical signs in dogs with osteoarthritis (OA). DESIGN: Randomized, controlled, multicenter clinical trial. ANIMALS: 217 client-owned dogs with clinical and radiographic signs of OA. PROCEDURE: Dogs were randomly assigned to be treated with meloxicam (n = 105; 0.2 mg/kg [0.09 mg/lb], SC, once on day 1, then 0.1 mg/kg [0.045 mg/lb], PO, q 24 h, for 13 days) or a placebo (n = 112). A general clinical score was assigned by investigators on days 1 (ie, prior to initiation of treatment), 8, and 15 on the basis of severity of lameness, extent of weight bearing, and severity of signs during palpation of the affected joint. Owners and investigators provided overall evaluations on days 8 and 15. RESULTS: Dogs treated with meloxicam had significantly greater improvements in general clinical scores, compared with baseline scores, on days 8 and 15 than did dogs treated with placebo. On days 8 and 15, percentages of dogs treated with meloxicam in which owners and investigators considered treatment to be successful were significantly higher than percentages of control dogs in which treatment was considered to be successful. No abnormalities in hematologic and serum biochemical test results were detected. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that compared with administration of a placebo, administration of meloxicam for 14 days significantly improved the clinical condition of dogs with OA without causing adverse effects.     

Prospective study of bacterial overgrowth syndrome in eight dogs

Eight dogs with cutaneous lesions, clinical signs and cytological findings compatible with bacterial overgrowth syndrome were compared with four healthy dogs. The affected dogs were treated for 28 days with 30 mg/kg/day cephalexin. The results showed that the syndrome was a superficial cutaneous disorder characterised by marked pruritus, greasy seborrhoea, offensive odour, erythema, lichenification, hyperpigmentation, excoriations and alopecia involving principally the ventral aspect of the body, but no papules, pustules, epidermal collarettes or crusts; it was caused by overgrowths of Staphylococcus intermedius all over the body surface. Histopathological findings included a superficial, perivascular, hyperplastic and spongiotic dermatitis with a mixed inflammatory infiltrate, but no lesions suggestive of a true pyoderma. In the affected dogs, anti-staphylococcal immunoglobulin G levels were high, but anti-staphylococcal immunoglobulin E levels were low, suggesting that staphylococcal hypersensitivity is not the underlying pathogenic process. The antibiotic treatment improved the condition of all the dogs, but five of the eight had an underlying allergic skin disease.     

Identification of Rickettsiae in Cutaneous i Biopsy Specimens From Dogs With Experimental Rocky Mountain Spotted Fever

Direct immunofluorescence reaction for Rickettsia rickettsii was performed on formalin-fixed, paraffin-embedded cutaneous biopsy specimens collected from dogs with experimental Rocky Mountain spotted fever (RMSF). A technique of trypsin digestion of deparaffinized, rehydrated sections was successful in demonstrating discrete, immunofluorescent organisms in endothelia and adjacent vessel walls in the dermis. R rickettsii was identified only in grossly evident dermal lesions (macular rash or oral vesicles) and was not apparent in randomly collected biopsy specimens from clinically normal inguinal skin. These results suggest that clinical application of this technique for diagnosis of RMSF may be limited in dogs without cutaneous lesions. (Journal of Veterinary Internal Medicine 1989; 3:8–11)     

Focal cutaneous vasculitis and alopecia at sites of rabies vaccination in dogs

A focal cutaneous lesion developed at the site of previous rabies vaccine administration in 13 dogs. Ten of the affected dogs were Poodles. The interval between vaccination and first observation of the lesion varied from 3 to 6 months. Skin lesions were hyperpigmented, alopecic macules, 2 to 5 cm in diameter. The consistent histologic lesion was vasculitis affecting arterioles of the deep dermis and subcutis. Other histologic lesions included epidermal, follicular, and adnexal atrophy, hyperpigmentation, chronic septal panniculitis, fat necrosis, and focal lymphocytic nodules in the deep dermis and subcutis. Rabies-specific fluorescence was seen in the walls of dermal blood vessels and in the epithelium of hair follicles in each of 3 dogs tested. Immunoglobulin G was detected in similar locations in one of 3 dogs tested. No difference in serum neutralizing anti-rabies antibody titers were detected between 5 affected dogs tested and 4 clinically normal dogs.     

Clinical efficacy and tolerance of meloxicam in dogs with chronic osteoarthritis

A clinical trial was conducted to evaluate the safety and efficacy of the nonsteroidal anti-inflammatory drug meloxicam in dogs with chronic osteoarthritis. Forty clinical cases were enrolled in the 2-phase study. Phase 1 compared therapeutic efficacy and tolerance of meloxicam or placebo for 1 week. Phase 2 involved a 4-week evaluation of the drug's clinical efficacy and tolerance. Clinical efficacy was evaluated by using a scoring system that assessed specific lameness, general stiffness, painful rise, exercise intolerance, and behavior. Evaluations demonstrated significant reductions (P < 0.05) in clinical signs of osteoarthritis following 4 weeks of drug therapy. Side effects were minimal in extent and duration. The drug was accepted without problems in the majority of cases. The findings of this investigation suggest that the efficacy, tolerance, and formulation of meloxicam oral suspension make it well suited for the treatment of chronic osteoarthritis in the dog.     

Analgesic effect of meloxicam in canine acute dermatitis--a pilot study

A double-blind trial was performed on 12 client-owned dogs suffering from acute and painful dermatitis. Clinically these cases represented pyotraumatic dermatitis and pyotraumatic folliculitis. Six dogs were injected with meloxicam and 6 were given placebo. Signs of pain were recorded on a visual analogue scale before administering the drug. This was repeated over the following 2-3 days. All dogs were treated with cephalexin orally. Six dogs given meloxicam and cephalexin showed an average decrease of pain on day 2 of 28.3%, whereas the 6 dogs given placebo and cephalexin showed an average decrease of pain on day 2 of 8.3%. When compared in the Wilcoxon two-sample test, using change in percent and absolute change, the 2 groups yielded p = 0.026 and p = 0.064 respectively. These findings indicate that meloxicam has an analgesic effect on acute dermatitis in dogs.     

Effects of preoperative administration of meloxicam on whole blood platelet aggregation, buccal mucosal bleeding time, and haematological indices in dogs undergoing elective ovariohysterectomy

The purpose of the study was to evaluate the effect of preoperative administration of meloxicam, a non-steroidal anti-inflammatory drug used for pain control, on primary haemostasis in dogs. Twenty healthy female dogs undergoing elective ovariohysterectomy were enrolled in the study. Sixty minutes before pre-anaesthesia, a single dose of meloxicam (0.2 mg/kg) was randomly administered intravenously (IV) to 10 dogs (treatment group) while control dogs received an equivalent volume of saline solution IV. Platelet aggregation, buccal mucosa bleeding time, platelet count and haematological indices were measured at 0, 1, 6 and 24 h after administration of meloxicam. Since significant differences between groups were not observed for any of the measured parameters, preoperative administration of meloxicam may be used for pain control before elective ovariohysterectomy in healthy dogs, without compromising primary haemostasis.     

Cutaneous mucinosis in shar-pei dogs is due to hyaluronic acid deposition and is associated with high levels of hyaluronic acid in serum

Cutaneous mucinosis affects primarily shar-pei dogs. Hyaluronic acid (HA) is considered to be the main component of mucin and CD44 is the major cell surface receptor of HA, necessary for its uptake and catabolism. The aims of this study were to identify the composition of the mucin in cutaneous mucinosis of shar-pei dogs, investigate the correlation between the deposition of HA and the expression of CD44, and determine whether shar-pei dogs with cutaneous mucinosis presented with elevated levels of serum HA. In skin biopsies, the mucinous material was stained intensely with Alcian blue and bound strongly by the hyaluronan-binding protein. No correlation was found between the degree of HA deposition in the dermis and the expression of CD44 in the skin of shar-pei dogs affected or unaffected by cutaneous mucinosis. A clear positive correlation was found between the existence of clinical mucinosis and the serum HA concentration. In control dogs, serum HA ranged from 155.53 to 301.62 microg L(-1) in shar-pei dogs; without mucinosis it ranged from 106.72 to 1251.76 microg L(-1) and in shar-pei dogs with severe mucinosis it ranged between 843.51 to 2330.03 microg L(-1). Altogether, the results reported here suggest that mucinosis of shar-pei dogs is probably the consequence of a genetic defect in the metabolism of HA.     

Effect of carprofen, etodolac, meloxicam, or butorphanol in dogs with induced acute synovitis

OBJECTIVE: To compare the analgesic and anti-inflammatory effect of single doses of carprofen, etodolac, meloxicam, and butorphanol in dogs with induced acute synovitis (acute pain model) via kinetic gait analysis and orthopedic evaluation and examine measurement of serum C-reactive protein (CRP) concentration as an indicator of treatment efficacy. ANIMALS: 12 Beagles and 6 additional Beagles that were used only in serum CRP analyses. PROCEDURE: Acute synovitis was induced in right stifle joints of dogs via intra-articular injection of monosodium urate solution. Treatments included butorphanol (0.2 mg/kg, i.v.), carprofen (4 mg/kg, PO), etodolac (17 mg/kg, PO), or meloxicam (0.2 mg/kg, PO); control dogs received no treatment. The procedure was repeated (3-week intervals) until all dogs received all treatments including control treatment. Lameness was assessed on a biomechanical force platform and via orthopedic evaluations of the stifle joints; blood was collected to monitor serum CRP concentration. RESULTS: Compared with control dogs, treated dogs had significantly different vertical ground reaction forces and weight-bearing scores. Greatest improvement in lameness was observed in carprofen-treated dogs. Etodolac had the fastest onset of action. Compared with butorphanol treatment, only carprofen and etodolac were associated with significantly lower pain scores. An increase in serum CRP concentration was detected after intra-articular injection in all dogs; this change was similar among groups. CONCLUSIONS AND CLINICAL RELEVANCE: Carprofen, etodolac, and meloxicam had greater efficacy than butorphanol in relief of acute pain. Carprofen was most effective overall. In this acute pain model, serum CRP analysis was not useful to assess drug efficacy.     

Immediate type hypersensitivity in dogs induced by storage mites

Results of intradermal skin tests on 53 dogs, employing storage mite extracts as antigen, indicated that storage mite allergy is fairly common. Only four of 29 dogs exhibiting no allergic symptoms showed skin reactions to the most common storage mite, Acarus siro, whereas 18 out of 24 dogs with symptoms assumed to be associated with allergy showed such reactions. The passive cutaneous transfer test revealed that an immediate type hypersensitivity reaction was involved.     

A prospective study on canine atopic dermatitis and food-induced allergic dermatitis in Switzerland

Canine atopic dermatitis sensu stricto and food-induced allergic dermatitis are common canine skin conditions, which are often considered clinically undistinguishable. Several attempts have been made to describe populations of atopic dogs and determine breed predisposition but the results were often biased by the use of hospital populations as control group. The present study aims to describe a population of Swiss atopic and food-allergic dogs and to compare it with a data set representing more than 85% of all Swiss dogs. The study, which was carried out during 1 year in several practices and teaching hospital in Switzerland, describes a group of 259 allergic dogs, determines breed predisposition for atopic dermatitis and food-induced allergic dermatitis, compares the clinical signs and features of both conditions, and outlines the clinical picture of five frequently affected breeds.     

Comparison of vedaprofen and meloxicam in dogs with musculoskeletal pain and inflammation

In this randomised, multicentre clinical study, dogs with musculoskeletal pain and inflammation were treated with either vedaprofen or meloxicam administered orally at the recommended dose rates. Clinical examinations were carried out regularly and clinical severity scores assigned. In total, 214 cases (73 acute, 141 chronic) were evaluated. Treatment with vedaprofen and meloxicam was continued for 14 and 17 days, respectively, in the acute cases, and 38 and 39 days in the chronic cases. NSAID treatment resulted in a significant improvement in clinical scores. The overall response to treatment ('responders') at the final clinical examination was 89 per cent and 87 per cent in the acute cases and 72 per cent and 65 per cent in the chronic cases in the vedaprofen and meloxicam groups, respectively. Mild transient gastrointestinal signs were observed in both groups (11 per cent vedaprofen, 12 per cent meloxicam). Adverse effects related to NSAIDs resulted in treatment cessation in 5 per cent of the dogs in each group. Vedaprofen and meloxicam were efficacious in, and well tolerated by, most of the dogs in the study.     

Feline progressive histiocytosis

Histiocytic proliferative diseases include reactive and neoplastic proliferations of dendritic cells (DC) or macrophages. Various forms of DC proliferations have been documented in humans and dogs; their etiology is largely unknown. With the exception of a few case reports, histiocytic proliferations have not been characterized in cats. This study summarizes clinical, morphologic, and immunophenotypic features of a feline progressive histiocytosis (FPH) in 30 cats. There was no breed or age predilection. Females were more often affected than males. Solitary or multiple nonpruritic firm papules, nodules, and plaques had a predilection for feet, legs, and face. Lesions consisted of poorly circumscribed epitheliotropic (13/30) and nonepitheliotropic (17/30) histiocytic infiltrates of the superficial and deep dermis, with variable extension into the subcutis. The histiocytic population was relatively monomorphous early in the clinical course. With disease progression, cellular pleomorphism was more frequently encountered. Histiocytes expressed CD1a, CD1c, CD18, and major histocompatibility complex class II molecules. This immunophenotype suggests a DC origin of these lesions. Coexpression of E-cadherin, a feature of cutaneous Langerhans cells, was only observed in 3 cats. FPH followed a progressive clinical course; the lesions, however, were limited to the skin for an extended period of time. Terminal involvement of internal organs was documented in 7 cases. Treatment with chemotherapeutics or immunosuppressive and immunomodulatory drugs was not successful. The etiology of FPH remains unknown. FPH is best considered an initially indolent cutaneous neoplasm, which is mostly slowly progressive and may spread beyond the skin in the terminal stage.     

Canine atopic dermatitis in Greece: clinical observations and the prevalence of positive intradermal test reactions in 91 spontaneous cases.

Atopic dermatitis was diagnosed in a total of 91 dogs by combining the compatible historical evidence and clinical signs with the presence of one or more positive intradermal test reactions well correlated with the exposure to the aeroallergens and the seasonality of the clinical signs. Compared to the general hospital population Yorkshire terriers, Chinese Shar-Peis and cocker spaniels showed a strong predilection. No such predilection was found regarding the sex of the animals. The age of the dogs at the onset of the clinical signs ranged from 2 months to 8 years (median: 2.5 years). Moderate to severe pruritus, noticed in all the 91 dogs, was either localized (29/91) or generalized (64/91) and non-seasonal (43/91), seasonal (19/91) or of unknown seasonality (29/91). The most common cutaneous lesions included erythema, hyperpigmentation, hypotrichosis and crusts; their body distribution was generalized (64%) or localized (36%) with the feet as the most common site of involvement. Five dogs that had unlesional skin were significantly younger and had been pruritic for a shorter period of time compared to the majority of our study population. Otitis externa (43/91) and bacterial pyoderma (30/91) were the most common conditions associated with atopic dermatitis, while the prevalence of Malassezia dermatitis was very low (2/91). Of the other allergic skin diseases flea allergic dermatitis was the most common (29/91) followed by food hypersensitivity (2 out of the 15 dogs tested). The majority of the dogs demonstrated multiple sensitivities to the 50 aeroallergens tested, while domestic mites (77/91), and particularly Dermatophagoides farinae (64/91), were the most commonly implicated. The total number of the positive intradermal test reactions was increasing parallel to the age of the dogs but it was negatively associated with the presence of skin lesions on the carpal and tarsal joints.     

Identification of allergens responsible for canine cutaneous adverse food reactions to lamb, beef and cow's milk

Lamb, beef and cow's milk are common causes of cutaneous adverse food reactions in dogs. The aim of this study was to identify the proteins responsible for cutaneous adverse reactions to these foods. Ten dogs with allergen-specific serum immunoglobulin (Ig)E to lamb, beef and cow's milk were included in the study. These dogs had been diagnosed with cutaneous adverse food reactions by convincing clinical history and food-elimination diet trials followed by challenge exposure. Sera were analysed by enzyme-linked immunosorbent assay with bovine proteins and SDS-PAGE immunoblots with lamb, beef and cow's milk extracts. All the dogs had specific IgE against bovine IgG, and it was the only protein in the cow's milk extract that bound IgE from the sera studied. In the lamb and beef extracts, the major allergens recognized by the specific IgE of most sera had molecular masses between 51 and 58 kDa, which were identified as phosphoglucomutase and the IgG heavy chain. Other IgE-binding proteins with molecular masses of 27, 31, 33, 37 and 42 kDa were also detected with some sera. Our results indicate that bovine IgG is a major allergen in cow's milk and hence it appears to be a source of cross-reactivity with beef and probably with lamb because of the high homology with ovine immunoglobulins. These results are similar to those found for meat allergy in humans. However, this is the first time that phosphoglucomutase has been identified as an important allergen involved in allergic reactions to lamb and beef.