Canine sterile neutrophilic dermatosis (resembling Sweet's syndrome) with severe extracutaneous manifestations.

INTRODUCTION: Sterile neutrophilic dermatosis is a rare disease in dogs, similar to Sweet's syndrome in humans. This case report describes the treatment of a 2-year old Bearded Collie that was presented with a 3-week history of fever, hind-limb weakness, peripheral lymphadenomegaly and leucocytosis. Blood tests revealed severe leukocytosis, renal azotaemia, elevated liver enzymes and bilirubinaemia. Skin lesions started to appear in week four. Histology revealed a sterile neutrophilic dermatitis resembling Sweet's syndrome. The dog displayed extracutaneous manifestations, including fever, polyarthritis, a severe leukemoid reaction, anaemia, hepatopathy and nephropathy. Issues regarding the use of criteria for the diagnosis of Sweet's syndrome in humans that are used for dogs with sterile neutrophilic dermatosis, are discussed in this case report. The condition resolved with dexamethasone and mycophenolate mofetil as a novel steroid-sparing therapy. Three months later the dog relapsed, which rapidly responded to short-term dexamethasone treatment and temporarily increased mycophenolate mofetil dosage.

INTRODUCTION: La dermatose neutrophilique stérile est une maladie rare chez le chien, semblable au syndrome de Sweet chez l'homme. Ce rapport de cas décrit le traitement d'un Bearded Collie de 2 ans présentant des antécédents de fièvre pendant 3 semaines, une faiblesse des membres postérieurs, une lymphadénomégalie périphérique et une leucocytose. Les analyses de sang ont révélé une leucocytose grave, une azotémie rénale, une élévation des enzymes hépatiques et une bilirubinémie. Des lésions cutanées ont commencé à apparaître à la quatrième semaine. L'histologie a révélé une dermatite neutrophilique stérile ressemblant au syndrome de Sweet. Le chien présentait des manifestations extracutanées telles que fièvre, polyarthrite, réaction leucémoïde sévère, anémie, hépatopathie et néphropathie. Les questions relatives à l'utilisation des critères de diagnostic du syndrome de Sweet chez l'homme chez les chiens atteints de dermatose neutrophilique stérile sont abordées dans le présent rapport de cas. La maladie a été traitée avec la dexaméthasone et le mycophénolate mofétil en tant que thérapie innovante permettant d'économiser des stéroïdes. Trois mois plus tard, le chien a rechuté mais a rapidement répondu à un traitement de courte durée à la dexaméthasone et à une augmentation temporairement la dose de mycophénolate mofétil.

Salivary cortisol concentrations in healthy dogs and dogs with hypercortisolism.

BACKGROUND: Measurement of salivary cortisol is a useful diagnostic test for hypercortisolism (HC) in humans. OBJECTIVES: To determine whether measurement of salivary cortisol concentration is a practical alternative to plasma cortisol to diagnose HC, to validate the use of salivary cortisol, and to examine the effect of time of day and sampling location on salivary cortisol. ANIMALS: Thirty healthy dogs and 6 dogs with HC. METHODS: Prospective, observational clinical trial including healthy volunteer dogs and dogs newly diagnosed with HC. Salivary and plasma cortisol concentrations were measured with an immunoassay analyzer. Intra- and interassay variability, linearity, and correlation between salivary and plasma cortisol concentrations were determined. RESULTS: The required 300 microL of saliva could not be obtained in 88/326 samples from healthy dogs and in 15/30 samples from dogs with HC. The intra-assay variability for measurement of salivary cortisol was 5-17.7%, the interassay variability 8.5 and 17.3%, and the observed to expected ratio 89-125%. The correlation (r) between salivary and plasma cortisol was 0.98. The time of day and location of collection did not affect salivary cortisol concentrations. Dogs with HC had significantly higher salivary cortisol values than healthy dogs (10.2 +/- 7.3 nmol/L versus 1.54 +/- 0.97 nmol/L; P < .001). CONCLUSIONS AND CLINICAL IMPORTANCE: The ROCHE Elecsys immunoassay analyzer correctly measured salivary cortisol in dogs. However, a broad clinical application of the method seems limited, because of the large sample volume required.

Comparison of 2 doses of recombinant human thyrotropin for thyroid function testing in healthy and suspected hypothyroid dogs.

BACKGROUND: Various protocols using different doses of recombinant human thyrotropin (rhTSH) in TSH stimulation testing have been described. However, the influence of TSH dosage on thyroxine (T4) concentration has not yet been evaluated in suspected hypothyroid dogs. OBJECTIVE: To evaluate the effectiveness of 2 doses of rhTSH. ANIMALS: Fifteen dogs with clinical signs consistent with hypothyroidism and abnormal stimulation results with 75 microg rhTSH and 18 clinically healthy dogs. METHODS: All dogs were stimulated with 75 and 150 microg rhTSH IV in a 1st and 2nd stimulation test, respectively. Blood samples were taken before and 6 hours after rhTSH administration for determination of total T4 concentration. RESULTS: Using the higher dose led to a normal test interpretation in 9 of the 15 dogs, in which stimulation had been abnormal using the lower dose. Based on follow-up information, hypothyroidism was excluded in 7 of these 9 dogs. In all 6 dogs with a blunted response to the higher dose, hypothyroidism could be confirmed. Healthy dogs showed significantly higher post-TSH T4 concentrations with the higher compared with the lower dose. Post-TSH T4 concentrations after TSH stimulation were not related to dogs' body weight in either healthy or diseased dogs. CONCLUSIONS AND CLINICAL RELEVANCE: TSH dose significantly influenced test interpretation in suspected hypothyroid dogs. Differentiation between primary hypothyroidism and nonthyroidal disease was improved with 150 microg rhTSH. Because this effect was independent of the dogs' body weight, the higher dose is recommended in dogs that have concurrent disease or are receiving medication.