2017 ACVIM Forum Research Abstract Program

In general, SRMA is characterized by fever, neck pain, neutrophilia, increased levels of IgA and CRP, neutrophilic pleocytosis, and contrast enhancement of the meninges on MR scanning. The present cases did not have these features of SRMA, while mononuclear or mixed pleocytosis, diffuse spinal lesions on MR images, and excellent responsiveness to glucocorticoid were commonly noted in all dogs. The objective of this study was to evaluate the pharmacokinetics (PK) of cytarabine (CA) after subcutaneous (SC) administration to dogs with meningoencephalomyelitis of unknown etiology (MUE). Twelve client-owned dogs, from 22 months to 10 years old, and weighing 2.5-39.2 kg, received a single SC dose of CA at 50 mg/m 2 for treatment of MUE. A sparse sampling technique was used to collect pharmacokinetic data. Four samples were collected from each dog to cover the time period from 0 to 360 minutes after administration. All dogs were concurrently on an oral prednisone dose of 0.5-2 mg/kg/day. Plasma CA concentrations were measured by HPLC and pharmacokinetic parameters were estimated using nonlinear mixed effects modeling (NLME). Plasma drug concentrations ranged from 0.05 to 2.8 lg/mL. The population estimate (CV%) for elimination half-life and Tmax of cytarabine in dogs was 0.7 (46.2) h and 0.8 (11.3) h, respectively. The volume of distribution per fraction absorbed was 0.7 (38.4) L/kg. Mean plasma concentration of CA for all dogs was at or above 1.0 lg/mL at the 30, 60, 90, and 120-minute time points. In this study, the pharmacokinetics of CA in dogs with MUE after a single 50 mg/m 2 SC injection in dogs was similar to what has been previously reported; there was moderate variability in the population estimates in this small clinical population of dogs. The purpose of this study was to identify the presenting complaints, neurologic findings, diagnosis, and outcomes in dogs and cats with cavernous sinus syndrome (CSS).