Table of Contents and Abstracts

A 7-year-old spayed female beagle was presented to its primary veterinary practice with vomiting, lethargy, and signs of hemorrhage. Investigations revealed severe thrombocytopenia and regenerative anemia. Following referral and further investigations, an initial diagnosis of primary immune thrombocytopenia was reached. Treatment with vincristine and prednisolone was initiated; however, the platelet count failed to increase, prompting the addition of cyclosporine. The platelet count temporarily improved but never normalized and subsequently declined again. A bone marrow biopsy confirmed a diagnosis of amegakaryocytic thrombocytopenia. Adjustments in treatment, including initiation of azathioprine, led to an increase in the platelet count. However, following an acute onset of respiratory distress, the owner perceived the dog’s quality of life to be poor, leading to a decision for euthanasia. This case highlights the diagnostic challenges of distinguishing amegakaryocytic thrombocytopenia from primary immune thrombocytopenia and the complexities of managing this rarely reported condition in animals.

Key clinical message:
This report describes the clinical presentation, diagnostic investigation, and treatment of a case of amegakaryocytic thrombocytopenia. It highlights the diagnostic challenges presented to confirm this pathology in our patients. Early consideration of bone marrow examination is warranted in the diagnostic evaluation and management of refractory thrombocytopenia, given that the prognosis for and therapeutic implications of amegakaryocytic thrombocytopenia differ significantly from those related to other etiologies.

A 4-year-old Arabian cross paint mare was referred for evaluation of chronic mucopurulent discharge and epiphora of the left eye. Ophthalmic and radiographic evaluations confirmed distal nasolacrimal duct atresia with absence of the nasolacrimal orifice. Initial minimally invasive treatments, including guidewire-assisted catheterization and diode laser photoablation, were unsuccessful. Definitive treatment was achieved using a Fogarty arterial embolectomy catheter under standing sedation. Controlled balloon inflation and deflation enabled progressive dilation of the obstructed duct, and a surgical mucosal opening over the balloon permitted creation of a nasal orifice. A temporary stent was maintained for 4 wk, resulting in successful restoration of nasolacrimal drainage without recurrence of epiphora. Twelve months after catheter removal, no recurrence of ocular discharge was noted. This case report highlights a minimally invasive, effective technique for treating distal nasolacrimal duct atresia in horses when other neocanalization methods are unsuccessful.

Key clinical message:
A Fogarty catheter-assisted neocanalization offered a practical and effective option for restoring nasolacrimal duct patency in a horse with distal duct atresia and absence of the nasal orifice, providing a minimally invasive alternative when conventional methods failed.

This report describes the diagnosis and successful management of a yearling filly with Coombs-positive anemia, thrombocytopenia, and fungal pneumonia. Diagnostic procedures, including thoracic ultrasonography and radiography, respiratory pathogen PCR testing, and evaluation of tracheal wash and bronchoalveolar lavage samples established multi-pathogen lower respiratory tract infection including a fungal agent. Orally administered voriconazole was a key component of treatment in this case to successfully eliminate fungal infection, alongside therapies for managing hematologic disease. This case demonstrated the importance of comprehensive diagnostic evaluation and reliance on current literature to successfully resolve a complicated medical situation that was expected to have a poor prognosis.

Key clinical message:
The pharmacokinetics of orally administered voriconazole have been established in horses. This drug can be economic and effective for the treatment of some fungal respiratory infections of horses.

An 11-year-old Turkish angora cat was presented with a mass in the right forelimb phalangeal region. Two years earlier, the cat had undergone surgical resection of a dorsal interscapular mass. Before initiating anticancer therapy, surgical incisional biopsy of a phalangeal region mass was done, followed by histopathologic and immunohistochemical analyses. The tumor cells demonstrated positive immunohistochemical labelling for desmin, vimentin, and myoblast determination protein 1, supporting a diagnosis of rhabdomyosarcoma (RMS). Histologic features were consistent with an embryonal subtype of RMS. Accordingly, a right forelimb amputation was completed. To our knowledge, this is the first reported case of a digital RMS in a cat. Because RMS is a rare tumor in cats, it is essential to study the clinical presentation, hematologic and serologic changes, treatment responses, and prognosis. Suitably, this case report provides valuable insight into the management of similar cases in cats.

Key clinical message:
This first reported case of digital RMS in a cat highlights the importance of studying the clinical presentation and treatment of RMS in feline patients.

A 12-month-old miniature horse filly was presented because of laminitis, suspected lymphangitis, and pyrexia. Although the filly’s initial physical examination and diagnostic tests suggested an infectious etiology, ultrasonographic findings were suspicious for generalized steatitis. This was confirmed via histopathology. The filly experienced full recovery with continued resolution of clinical signs at 18 mo after presentation. This case included aspects similar to those of previously reported clinical presentations, as well as long-term follow-up in a breed that is not overrepresented, providing additional documentation of an uncommon condition in a miniature horse in North America.

Key clinical message:
Generalized steatitis is an uncommon condition in equids in North America. This case provided an example to aid in recognition, diagnosis, and treatment associated with a favorable outcome.

An 8-year-old neutered male domestic shorthair cat with a history of persistent diarrhea and a previous diagnosis of feline gastrointestinal eosinophilic sclerosing fibroplasia in the jejunum was presented to our hospital. Abdominal ultrasound examination revealed a hepatic lesion with a diffuse altered echostructure. Histopathologic analysis confirmed the diagnosis of hepatic feline eosinophilic sclerosing fibroplasia (FESF), marked by multinodular lesions with abundant inflammatory cell infiltrates. Despite treatment with corticosteroids and supportive care, the cat was euthanized 15 d after diagnosis due to the deterioration of its health status.

This report aims to highlight the necessity to include FESF within differential diagnoses when diagnosing liver masses in cats, particularly those with previous gastrointestinal involvement. It emphasizes the need for histopathologic confirmation and highlights the challenges in diagnosing this condition, especially regarding its multifocal nature and potential misdiagnosis as tumors. With only 2 documented cases of liver involvement available, the prognosis for hepatic FESF remains unclear, warranting further investigation to establish definitive therapeutic guidelines.

Key clinical message:
Feline eosinophilic sclerosing fibroplasia should be considered as a differential diagnosis for cats presented with liver masses. The diagnosis relies on careful history-taking and clinical examination, mainly in the presence of a previous gastrointestinal mass. Histopathologic evidence is essential for a definitive diagnosis.

A 14-year-old spayed female Maltese dog had been diagnosed with inflammatory bowel disease (IBD) via surgical biopsy and histopathologic findings. The dog had shown stable clinical control with prednisolone for 2 y but subsequently developed diarrhea, and serum albumin levels could not be adequately controlled. Despite titrating up the prednisolone dosage (1 mg/kg, PO, q12h), serum albumin concentration remained low and diarrhea persisted. Diagnostic imaging identified the underlying cause of the gastrointestinal signs as segmental eccentric small intestine wall thickening with homogenous hypoenhancement. A surgical resection of the affected segment was undertaken, primarily for histopathologic examination to identify the underlying cause rather than for therapeutic purposes. Postoperatively, medical management was continued, and the therapeutic response to medical therapy improved as the prednisolone was gradually tapered. Stable management was ultimately achieved at a prednisolone dosage of 0.25 mg/kg, PO, q24h, once.

Key clinical message:
In veterinary medicine, IBD is generally managed with medical therapy, and poor prognosis may occur if the clinical signs are not controlled. In certain cases, however, a surgical approach may offer benefits in the management of IBD. In the case reported herein, surgical resection was conducted on the segments of intestine with severe inflammation in a 14-year-old spayed female Maltese dog diagnosed with IBD that was not controlled by medical therapy. After surgery, the IBD was managed successfully with prednisolone.

Background
Pulmonary metastasis is a major cause of mortality in dogs with cancers, but traditional thoracic imaging methods, such as radiographs and computed tomography (CT), have limited sensitivity for detecting small nodules. ¹⁸F-fluorodeoxyglucose positron emission tomography/CT (¹⁸F-FDG PET/CT) offers functional imaging capabilities and may improve metastasis detection and cancer staging. However, its role in evaluating pulmonary nodules in dogs is not well understood, and species-specific imaging parameters are lacking.

Objective
This study aimed to characterize metastatic pulmonary nodules in dogs using ¹⁸F-FDG PET/CT, with a focus on associations among nodule size, location, and maximum standardized uptake value (SUVmax).

Animals and procedure
A total of 109 pulmonary nodules detected on ¹⁸F-FDG PET/CT in dogs with aggressive cancer were retrospectively reviewed by a Board-certified radiologist. Descriptive and analytical statistical analyses were done to assess relationships between imaging factors.

Results
Nodule size and SUVmax varied highly, with a median diameter of 6.4 mm (range: 5 to 20 mm) and median SUVmax of 3.72 (range: 0.7 to 27.45). A moderate but positive correlation was noted between nodule size and SUVmax (τ = 0.526; P < 0.001). Nodule location did not significantly affect SUVmax. Furthermore, using a proposed SUVmax cutoff of 2.5 obtained from a human guideline, 34.9% (38/109) of nodules were classified as nonmalignant.

Conclusion and clinical relevance
Our findings contribute to the growing body of research on ¹⁸F-FDG PET/CT imaging in canine oncology and highlight the need for a dog-specific SUVmax threshold to improve diagnostic accuracy. We emphasize the need for larger prospective studies to refine interpretation of SUVmax values for metastatic pulmonary nodules in dogs.

Objective
This study compared the efficacy of mucosal prime and systemic boost vaccination of young beef calves to the current industry standard of systemic prime in the presence of maternal antibodies.

Animals
April-born commercial crossbred beef calves (N = 22) were enrolled as neonates with a mean body weight of 37.7 ± 5.3 kg.

Procedure
At birth, 11 calves (PRB) were intranasally administered a commercial combination modified live virus [bovine herpesvirus type 1 (BoHV1), bovine respiratory syncytial virus (BRSV), bovine parainfluenza virus type 3 (BPIV3)] mucosal vaccine and 11 calves (INJ) remained unvaccinated. At ~39 ± 2 d of age, all 22 calves were subcutaneously administered a combination modified live virus systemic vaccine (BoHV1, BRSV, BPIV3, and bovine viral diarrhea virus types 1 and 2). At weaning (159 ± 2 d of age), calves were challenged by coinfection with BRSV and BPIV3 and monitored 8 d for health and immunologic outcomes.

Results
The INJ group had an increased risk of greater group cumulative clinical scores on Day 8 and rectal temperature > 39.5°C on Days 7 and 8 post-challenge. The INJ calves had lower arterial oxygenation than the PRB on Day 6, indicating more severe lung pathology. Shedding of BRSV and BPIV3 was greater on Days 5 and 7 for INJ compared to PRB.

Conclusion
Mucosal priming and systemic boosting resulted in fewer lung lesions and less shedding of virus post-viral challenge at weaning than systemic priming of young calves.

Clinical relevance
Prime-boost vaccination optimizes immune development toward weaning.

Background
Ocular effects, most notably retinal degeneration, have been linked to enrofloxacin use in cats. However, data have been limited and there is a need for formal evidence synthesis to better understand and characterize these potentially life-altering adverse events.

Objective
The objective was to describe data regarding ocular adverse events associated with enrofloxacin administration in cats and to identify information gaps.

Procedure
A scoping review was conducted, searching the MEDLINE (via the Ovid platform), Web of Science, and CAB Abstracts bibliographic databases.

Results
Six references passed title and abstract screening, then full text screening: 1 case series (n = 17 cases), 3 single case reports, 1 conference research abstract (n = 2 cases), and 1 pharmacovigilance summary publication. There were reports of enrofloxacin-associated adverse ocular events in 163 cats. Loss of vision, mydriasis, and altered pupillary light responses were most commonly reported. Increased tapetal reflectivity, retinal vessel attenuation, and retinal degeneration were the most common abnormalities on ophthalmological examination. Most cats had permanent blindness or altered vision. Most cats had received doses well in excess of the current label recommendation, but 15/103 (14%) cats for which dosing data were available were reported to have received ≤ 5 mg/kg per day.

Conclusion and clinical relevance
Suspected enrofloxacin-associated ocular disease in cats typically resulted in long-term blindness or visual deficits, but full recovery occurred in a subset. Inadequate data were available to assess potential risk factors (e.g., age, dose). Although a dose of ≤ 5 mg/kg per day will likely reduce the likelihood of adverse events, these data indicated that ocular disease was still possible at that dosage.