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.

Hypovolemia induced systolic anterior motion of the mitral valve in two dogs

Systolic anterior (septal) motion of the mitral valve (SAM) is a common secondary phenomenon in hypertrophic cardiomyopathy (HCM) in people and cats. In humans, it is increasingly recognized that SAM may be found in other cardiac and non-cardiac disease states. In small animal cardiology, SAM unassociated with HCM has been described in dogs with mitral valve dysplasia and right ventricular pressure overload. In this report, we describe two cases of dogs where transient SAM was caused by hypovolemia. When SAM was present both dogs showed pseudohypertrophy and tachycardia. Important factors in the genesis of SAM in this scenario are probably hypovolemia induced changes in left ventricular geometry affecting the orientation of the mitral valve apparatus combined with elevated catecholamine levels. SAM associated with increased wall thickness is not pathognomonic of HCM; this observation is of particular clinical importance when extrapolated to species where HCM is highly prevalent, e.g., cats. An echocardiographic diagnosis should always be evaluated together with full clinical assessment of history and physical examination.