Severe Bilateral Sialadenitis of the Mandibular and Parotid Salivary Glands with Severe Panniculitis in a 2-Year-old Standard Poodle.

A 2-year-old male neutered Standard Poodle weighing 17.9 kg was presented to their primary care veterinarian for enlarged bilateral submandibular swellings following an interdog altercation sustained in the previous weeks. Cytology performed following fine-needle aspirates of the regions of swelling was inconclusive, and the patient was treated empirically with Clavaseptin. Despite treatment, the submandibular swellings continued to enlarge, and right-sided intermittent epistaxis was reported. On biochemical profile, there was mild hypercalcemia and mild hyperglobulinemia. The computed tomography (CT) findings were indicative of severe multifocal sialadenitis with severe regional cellulitis and inflammatory lymphadenopathy. Histopathology and cytology results described mixed inflammation of the salivary gland. Methenamine silver staining and Fite's acid-fast staining were negative. Aerobic and anaerobic cultures were negative. Targeted, next-generation DNA sequencing detected no known fungi or bacterial pathogens. These findings were consistent with the diagnosis of severe bilateral mandibular sialadenitis, panniculitis, and lymphadenopathy. The patient was prescribed enrofloxacin, clindamycin, phenobarbital, and prednisolone for 1 month. One week after initiating treatment, the patient had a significant reduction in size of the salivary glands. CT imaging was helpful in the diagnosis of this patient and allowed the clinician to identify which submandibular anatomical structures were abnormal, guiding subsequent diagnostic decisions to provide medical management to resolve the condition.

Dilution of maropitant (Cerenia) in lactated Ringer solution prolongs subcutaneous drug absorption and reduces maximum plasma concentration.

OBJECTIVE: The aim of this study was to determine whether the pharmacokinetics of maropitant, administered SC as a commercially available maropitant-containing injectable product (Cerenia Injectable), differ when combined with lactated Ringer solution prior to administration. ANIMALS: We used 6 adult spayed female Beagle dogs between 3 and 6 years of age, with a mean weight of 9.58 kg. PROCEDURES: In this randomized crossover study, the dogs underwent 2 treatment protocols separated by a 14-day washout period: (1) an SC injection of 1 mg/kg of Cerenia Injectable (maropitant citrate; 10 mg/mL) and (2) 1 mg/kg of Cerenia Injectable diluted in 10 mL/kg of lactated Ringer injectable solution (LRS) given SC. Plasma maropitant concentrations were assessed by mass spectrometry. Pharmacokinetic analysis was performed using pharmacokinetic and pharmacodynamic data-analysis software to determine maximum plasma concentration (Cmax), time to reach maximum concentration, half-life, total exposure to the drug, mean residence time, clearance rate per fraction absorbed, and absorption and elimination kinetic parameters. RESULTS: Cmax was reduced by 26% (P = .002), the absorption rate constant decreased 80% (P = .031), and the absorption half-life increased when Cerenia was administered diluted in LRS. CLINICAL RELEVANCE: Administration of maropitant (Cerenia) diluted in LRS had a pharmacokinetic impact, resulting in a significantly reduced Cmax and slower absorption. Clinical efficacy was not assessed in this study.