A Novel CARMIL2 Immunodeficiency Identified in a Subset of Cavalier King Charles Spaniels with Pneumocystis and Bordetella Pneumonia.

Pet dogs are a valuable natural animal model for studying relationships between primary immunodeficiencies and susceptibility to Pneumocystis and other opportunistic respiratory pathogens. Certain breeds, such as the Cavalier King Charles Spaniel, are over-represented for Pneumocystis pneumonia (PCP), suggesting the presence of a primary immunodeficiency in the breed. Here, we report the discovery of a CARMIL2 nonsense variant in three Cavalier King Charles Spaniel dogs with either PCP (n = 2) or refractory Bordetella pneumonia (n = 1). CARMIL2 encodes a protein that plays critical roles in T-cell activation and other aspects of immune function. Deleterious CARMIL2 variants have recently been reported in human patients with PCP and other recurrent pneumonias. In addition to opportunistic respiratory infection, the affected dogs also exhibited other clinical manifestations of CARMIL2 deficiencies that have been reported in humans, including early-onset gastrointestinal disease, allergic skin disease, mucocutaneous lesions, abscesses, autoimmune disorders, and gastrointestinal parasitism. This discovery highlights the potential utility of a natural canine model in identifying and studying primary immunodeficiencies in patients affected by PCP.

Diagnostic Contribution of Bronchoalveolar Lavage Sampling and Fungal Culture in a Dog With Pulmonary Coccidioidomycosis.

A 7-year-old, male neutered, Miniature Australian Shepherd from Arizona was presented for evaluation of a 3-month history of progressive cough. Thoracic radiographs revealed a focal alveolar pulmonary pattern and suspected tracheobronchial lymph node enlargement. Serum anti-Coccidioides spp. IgM/IgG antibodies were not detected by agar gel immunodiffusion performed by 2 different reference commercial veterinary laboratories approximately 3.5 and 3.75 months after respiratory tract signs were first noted. The dog failed to respond to empiric therapy with a cough suppressant and various antibiotics. Tracheobronchoscopy and bronchoalveolar lavage (BAL) were subsequently performed and cytological examination of the BAL fluid identified marked neutrophilic inflammation characterized by mildly degenerate neutrophils and no infectious organisms. Bacterial cultures were negative but fungal cultures revealed growth of Coccidioides spp. Clinical signs improved shortly after initiation of fluconazole administration and the dog achieved long-term sustained clinical remission. Here, we provide a description of a dog with pulmonary coccidioidomycosis diagnosed with fungal culture of BAL fluid. Airway sampling with cytological examination and fungal culture should be considered in dogs with persistent respiratory related clinical signs, negative antibody serology, and that have lived in or traveled to endemic areas.

Prevalence and impact of cholecystitis on outcome in dogs with gallbladder mucocele.

BACKGROUND: Gallbladder mucocele is a potentially life-threatening extrahepatic biliary disease in dogs. The primary aims of this study were to evaluate the prevalence of cholecystitis in dogs with gross and histopathologically confirmed gallbladder mucocele and to investigate if there is an association between cholecystitis, including its subtypes (eg, acute, acute on chronic, with necrosis, chronic), and survival. Our secondary objective was to evaluate if there is an association between cholecystitis and intraoperative bacteriological culture positivity. KEY FINDINGS: Two hundred nineteen dogs with gallbladder mucocele were included in this multi-institutional retrospective study, of which 63 (28.8%) dogs had histopathological evidence of cholecystitis. The most common forms of cholecystitis were acute on chronic (n = 22/63, 34.9%) and with necrosis (n = 20, 31.7%). Thirty-one (14.1%) dogs had growth of at least 1 bacterial isolate; however, 88.7% had antimicrobials administered within the 48 hours before surgery or intraoperatively. There was not an association between cholecystitis or its subtypes and survival. Furthermore, there was not an association between cholecystitis and intraoperative bacteriological culture positivity. A total of 38 (17.4%) dogs either died or were euthanized during hospitalization. SIGNIFICANCE: Cholecystitis is a common comorbidity in dogs with gallbladder mucocele but was not associated with decreased survival.