Hypertrophic osteopathy associated with infective endocarditis in an adult boxer dog

A Holistic Approach to Bone Tumors in Dogs and Cats: Radiographic and Histologic Correlation

The skeletal system is a common site for neoplasia in dogs and cats, and primary bone tumors may develop from any of the mesenchymal tissues present in bone. Imaging and histopathology are routinely used in the diagnosis of bone tumors, and the 2 techniques are highly complementary. While imaging may be highly suggestive of a specific diagnosis and treatment may be instituted based on this, definitive diagnosis requires histopathology of either incisional or excisional biopsies or an amputation specimen. However, there are a number of diagnostic dilemmas when the pathologist interprets bone biopsy samples, such as distinguishing reactive bone and tumor bone, fracture callus and tumor bone, different benign fibro-osseous lesions, and different types of bone sarcoma. This review outlines the characteristic radiographic and histologic changes associated with these diagnostic problems to aid in resolving them. When a holistic approach is taken to evaluation of the signalment, history, and clinical, radiologic, and microscopic features, a diagnosis may be possible. The pathologist is greatly assisted in the interpretation of bone samples by having access to imaging and should routinely request either the images or the imaging reports if they are not received from submitting veterinarians.

Hypertrophic osteopathy in a cat with cardiac interventricular septal defect

A 3-year-old mixed-breed female cat was diagnosed with a ventricular septal defect of the heart through an echocardiogram. After a 9-month treatment, progressive and diffuse hard thickening of all limbs was observed, which on radiographic examinations, revealed a marked thickening of the long bones. The necropsy findings were limited to the appendicular skeleton and thoracic vertebrae, in addition to a severe cardiac interventricular septal defect and lung edema. The histological evaluation revealed severe replacement of the cortical bone by spongy bone in all bone fragments examined. This is the first report of hypertrophic osteopathy occurring in association with a cardiac malformation in a cat.

Squamous Cell Carcinoma of the Penis with Pulmonary Metastasis and Paraneoplastic Hypertrophic Osteopathy in a Dog

Squamous cell carcinoma of the penis was diagnosed by incisional biopsy of a penile mass in a 12 yr old intact male beagle dog presenting with hemorrhagic discharge from the prepuce. Penile amputation, orchiectomy with scrotal ablation, and scrotal urethrostomy were performed. Hypertrophic osteopathy secondary to pulmonary metastatic disease occurred 10 mo after the surgery. Palliative treatment with piroxicam was administered and led to complete resolution of the clinical signs of the pain. Sixteen months following surgery, the dog presented with significant dyspnea and anorexia and was euthanized due to poor prognosis. This case report describes a rare penile tumor, squamous cell carcinoma. Consequent paraneoplastic hypertrophic osteopathy and its palliative treatment are also reviewed.

Hypertrophic Osteoarthropathy: Clinical and Imaging Features

Hypertrophic osteoarthropathy (HOA) is a medical condition characterized by abnormal proliferation of skin and periosteal tissues involving the extremities and characterized by three clinical features: digital clubbing (also termed Hippocratic fingers), periostosis of tubular bones, and synovial effusions. HOA can be a primary entity, known as pachydermoperiostosis, or can be secondary to extraskeletal conditions, with different prognoses and management implications for each. There is a high association between secondary HOA and malignancy, especially non-small cell lung cancer. In such cases, it can be considered a form of paraneoplastic syndrome. The most prevalent secondary causes of HOA are pulmonary in origin, which is why this condition was formerly referred to as hypertrophic pulmonary osteoarthropathy. HOA can also be associated with pleural, mediastinal, and cardiovascular causes, as well as extrathoracic conditions such as gastrointestinal tumors and infections, cirrhosis, and inflammatory bowel disease. Although the skeletal manifestations of HOA are most commonly detected with radiography, abnormalities can also be identified with other modalities such as computed tomography, magnetic resonance imaging, and bone scintigraphy. The authors summarize the pathogenesis, classification, causes, and symptoms and signs of HOA, including the genetics underlying the primary form (pachydermoperiostosis); describe key findings of HOA found at various imaging modalities, with examples of underlying causative conditions; and discuss features differentiating HOA from other causes of multifocal periostitis, such as thyroid acropachy, hypervitaminosis A, chronic venous insufficiency, voriconazole-induced periostitis, progressive diaphyseal dysplasia, and neoplastic causes such as lymphoma. ^©RSNA, 2016.

Paraneoplastic hypertrophic osteopathy in 30 dogs

Paraneoplastic hypertrophic osteopathy (pHO) is known to occur in both canine and human cancer patients. While the pathology of pHO is well-described in the dog, very little information exists regarding the true clinical presentation of dogs affected with pHO. The primary objective of this study was to provide a more comprehensive clinical picture of pHO. To this end, we retrospectively identified 30 dogs and recorded data regarding presenting complaints and physical examination (PE) findings on the date of pHO diagnosis. As a secondary objective, any blood test results were also collected from the computerized records. The most common clinical signs included leg swelling, ocular discharge and/or episcleral injection, lameness, and lethargy. The most common haematological and serum biochemical abnormalities included anaemia, neutrophilia and elevated alkaline phosphatase. In addition to presenting a more detailed clinical description of pHO in the dog, these data support the previously described haematological, serum biochemical and PE abnormalities published in individual case reports.

Hypertrophic osteopathy associated with two pulmonary tumours and myocardial metastases in a dog: a case report

CASE HISTORY

A 16-year-old dog was presented to the University of Melbourne Veterinary Clinic and Hospital for dyspnoea and tachypnoea, which had been occurring over the previous 48 h prior to presentation.

CLINICAL FINDINGS

Physical examination findings included marked wheezing and inspiratory noises on thoracic auscultation. Diagnostic tests performed revealed a large pulmonary mass, the presence of hypertrophic osteopathy in the forelimbs and an abnormal myocardium. The patient continued to deteriorate while in hospital, and was euthanased at the owner's request. A post-mortem examination was carried out, which revealed the presence of two separate pulmonary masses, one of which was completely occluding the mainstem bronchus.

DIAGNOSIS

One tumour was histologically classified as an adenocarcinoma, the other as an extraskeletal osteosarcoma. The osteosarcoma had metastasised to the myocardium, spleen and kidneys. The forelimb changes were consistent with hypertrophic osteopathy.

CLINICAL RELEVANCE

This is the first reported case of two separate pulmonary masses in a dog, one of which metastasised to the myocardium. Hypertrophic osteopathy is a common pathological condition associated with a broad spectrum of diseases. The aim of this case report is to highlight the condition and remind clinicians of its relatively common incidence, as well as to prompt clinicians to look for underlying pathology. The current understanding of the pathophysiology of hypertrophic osteopathy is also discussed.

Infective endocarditis in dogs: diagnosis and therapy

Infective endocarditis (IE) is a bacterial disease that commonly occurs in dogs. Difficulty in diagnosis and underreporting of IE in dogs contribute to the reported low prevalence rate of the disease. The mitral and aortic valves are the worst affected by IE. Common causative microbial agents include Staphylococcus spp, Streptococcus spp, Escherichia coli, and Bartonella spp. Congestive heart failure, immune-mediated disease, and thromboembolism are the major complications of IE. Diagnosis of IE by echocardiography and long-term treatment with broad-spectrum antibiotics may contribute to the timely detection and treatment of the disease.

Systemic Conidiobolus incongruus infection and hypertrophic osteopathy in a white-tailed deer (Odocoileus virginianus)

Postmortem examination of a free-range white-tailed deer (Odocoileus virginianus) revealed severe emaciation, bilateral firm proliferation of the metatarsal diaphyses, and a large intrathoracic mass associated with the accessory lung lobe. Smaller masses were evident in the abomasum, duodenum, omentum, and the capsular surface of the liver. Microscopically, the masses were similar and were diagnosed as eosinophilic granulomas with intralesional fungal hyphae characteristic of Zygomycetes spp. Fungal hyphae were identified as Conidiobolus incongruus by 18S ribosomal RNA sequencing on fresh lung tissue. Furthermore, the proliferative lesions of the metatarsal bones along with the intrathoracic mass were compatible with hypertrophic osteopathy.