Fatal congenital peritoneopericardial diaphragmatic hernia in a sable antelope (Hippotragus niger) calf

Congenital peritoneopericardial diaphragmatic hernia was diagnosed in a 2-week-old sable antelope (Hippotragus niger) calf with subsequent fatal acute heart failure. Histopathological examination of the lung, liver and heart revealed lesions supportive of acute heart failure that consisted of pulmonary oedema, periacinar hepatocellular necrosis and myocardial degeneration and necrosis. The external pressure on the coronary arteries by the liver and abomasum most likely resulted in ischaemic injury of the cardiomyocytes and the resultant acute heart failure.https://wileyonlinelibrary.com/journal/vrc22022-06-13hj2022Centre for Veterinary Wildlife StudiesParaclinical Science

Widespread metastasis of a spermatocytic seminoma with concomitant hepatic peliosis in a Southern African hedgehog (Atelerixfrontalis)

A six-year-old intact male Southern African hedgehog (Atelerix frontalis) presented with a history of chronic mild to moderate weight loss, and sub-acute hind limb ataxia that progressed to complete paralysis, at which point the hedgehog was euthanised. At autopsy, a large multinodular pale mass had completely replaced the left testicle and transcoelomically metastasised to the diaphragm and the peri-renal area, from where it then invaded the vertebral column and spinal cord. Multifocal, irregular to round, well-demarcated, blood-filled, proliferative lesions were also present in the hepatic parenchyma. Histological analysis of both the testis and metastatic lesions revealed diffuse sheets of neoplastic cells with moderate pale cytoplasm, large irregular to round nuclei and mostly one prominent magenta nucleolus, consistent with metastatic seminoma. The neoplastic cells were negative for periodic acid–Schiff (PAS) stain and positive for CD117 by immunohistochemistry (IHC). Taken together with the morphology of the neoplastic cells and the advanced age of the animal, this is suggestive of a spermatocytic seminoma. Histological analysis of the liver revealed multifocal lesions consisting of large anastomosing blood-filled spaces bordered by compressed hepatocytes, consistent with hepatic peliosis. This is the first report of a neoplasm in the Southern African hedgehog (Atelerix frontalis), the first report of a metastatic seminoma in a hedgehog, together with diagnosis of spermatocytic subtype, and the first report of a hedgehog with concomitant hepatic peliosis.The Wellcome Trust.http://www.jsava.co.zaam2023Centre for Veterinary Wildlife StudiesParaclinical SciencesProduction Animal Studie

Kasabach-Merritt-like syndrome in a dog secondary to isolated splenic haemangiomatosis

A 13-year-old intact male miniature schnauzer presented with lethargy, distended abdomen and pallor. Pancytopenia was identified on complete blood count with a severe thrombocytopenia. Cavitatory severe splenomegaly was identified on abdominal ultrasound. Two weeks of immunosuppressive therapy had no effect on the thrombocytopenia and a splenectomy was performed. The platelet count returned to normal within 24 hours of splenectomy. Isolated splenic haemangiomatosis was confirmed on histopathology and immunohistochemistry. The anaemia and severe thrombocytopenia in conjunction with the ultrasound findings and histopathology are characteristic of Kasabach-Merritt syndrome in people. This is the first case of Kasabach-Merritt-like syndrome described in the dog.https://bvajournals.onlinelibrary.wiley.com/journal/20526121hj2021Companion Animal Clinical StudiesParaclinical Science

Clinical presentation and pathology of suspected vector transmitted African horse sickness in South African domestic dogs from 2006 to 2017

African horse sickness (AHS) is a fatal vector transmitted viral disease of horses caused by the African horse sickness virus (AHSV). This disease is characterised by circulatory and respiratory failure, resulting from vascular endothelial injury affecting many organs. The susceptibility of dogs to AHS has been demonstrated in the past following experimental infection through consumption of infected horse meat. Thirty three clinical cases of AHS in dogs (cAHS) have been documented, without a history of ingesting infected horse meat, over a period of 12 years. The clinical cases included in this study presented with a history of acute respiratory distress syndrome or sudden death. The macroscopic and histological changes were mostly characterised by acute interstitial pneumonia, serofibrinous pleuritis and mediastinal oedema. Confirmation of cAHS was obtained by AHS specific NS4 antibody immunohistochemistry and/or AHSV specific duplex real time RT-quantitative PCR. Here, we document the clinical and postmortem diagnostic features of confirmed cAHS cases with no history of ingestion of AHS infected horse meat.http://veterinaryrecord.bmj.comhj2018Paraclinical SciencesProduction Animal Studie

Pathology of fatal natural African horsesickness virus infection in dogs

African horsesickness (AHS) is a highly fatal arthropod-transmitted viral disease affecting mainly equids. Dogs are known to contract fatal AHS by ingestion to AHS-infected horse meat. At the Section of Pathology, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria a number of canine mortalities with no history of horse meat consumption have been diagnosed since 2006. Limited published information describing the pathological findings in AHSV-infected dogs however exists. This study is a retrospective survey focussing on providing a full macroscopic, histologic (including immunohistochemistry) and ultrastructural description of the pathological changes observed in dogs naturally infected by AHS virus. Clinically most dogs presented with severe dyspnoea that deteriorated rapidly and terminated in respiratory failure and death. Some of the dogs had a history of lethargy and anorexia of less than 24 hours. Macroscopically the most significant lesions were observed in the thoracic cavity and characteristically included severe acute interstitial pneumonia associated with mild serofibrinous pleuritis and moderate mediastinal oedema. Histopathologically the pulmonary findings included severe protein rich alveolar and septal oedema with randomly scattered areas of haemorrhage. In addition, acute inflammatory changes were present, characterised by mononuclear interstitial pneumonia and alveolar exudation, with hyperactivation of the alveolar capillary endothelial cells, alveolar macrophage proliferation and moderate diffuse hyperaemia. Immunohistochemical labelling revealed AHSV-specific positive labelling of the microvascular endothelial cells as well as scattered mononuclear leukocytes (monocytes and macrophages). The ultrastructural changes observed were supportive of vascular injury similar to those observed in horses infected by AHSV. The pathological findings observed in all cases were indicative of acute pulmonary inflammation of haematogenous origin, resulting in fatal immune- and pathogen induced vascular injury.Dissertation (MSc)--University of Pretoria, 2018.Paraclinical SciencesM.Med.VetUnrestricte

Metastatic extraskeletal myxoid chondrosarcoma in a greater kudu (Tragelaphus strepsiceros)

Extraskeletal myxoid chondrosarcoma was diagnosed on the ventral abdomen of a kudu with metastasis to the omentum and lungs. Histopathological examination of the large (20 cm × 10 cm) primary, multinodular, moderately cellular neoplastic mass was characterised by neoplastic mesenchymal cells arranged in strands and bundles, interspersed by multiple foci of cartilage immersed in a myxoid matrix. The neoplastic cells revealed diffuse vimentin and S100 positivity and the myxoid matrix was positive with Alcian blue. The microscopic examination in addition to the Alcian Blue and immunohistochemistry findings confirmed the diagnosis.http://vetrecordcasereports.bmj.comhj2020Paraclinical Science

Clinical presentation and management of African horse sickness in two dogs

A 10-month-old, spayed, female beagle (case 1) and an unrelated two-year-old, intact, female labrador retriever (case 2), both living in Pretoria, South Africa, presented individually on separate occasions with acute onset dyspnoea and severe hypoxia. Thoracic radiographs demonstrated severe, diffuse interstitial to alveolar lung patterns with mild pleural and mediastinal effusion. Mixed airway inflammation was seen on transtracheal aspirate cytology in case 1. Both cases received supportive therapy, but only one dog survived (case 2). African horse sickness (AHS) was diagnosed at necropsy based on histopathology and immunohistochemistry in case 1 and was diagnosed antemortally using reverse transcriptase-PCR on whole blood in case 2. To the authors’ knowledge, this is the first report to detail the haematological, biochemical, thoracic radiological, arterial blood gas and transtracheal aspirate cytology findings of AHS in dogs. This report also describes the treatment of a dog surviving clinical AHS infection.http://vetrecordcasereports.bmj.comhj2018Companion Animal Clinical StudiesParaclinical Science

Successful treatment of cutaneous squamous cell carcinoma in a captive green iguana (Iguana iguana)

Reptiles are popular exotic pets and green iguanas (Iguana iguana) are amongst the top ten most popular reptiles. Here we describe a captive 8-year-old female green iguana that was referred for treatment of a non-healing, discharging lesion on the side of the body. The lesion was surgically excised and histopathological analysis revealed an epidermal proliferation of neoplastic keratinocytes, with focal infiltration through the basement membrane, into the underlying superficial dermis. Marked dysplastic changes, characterized by multifocal dyskeratosis and keratin pearl formation were also noted. A diagnosis of cutaneous squamous cell carcinoma (SCC) was made. Two years later, the iguana has shown no signs of recurrence. This is the first report of successful treatment of cutaneous SCC in a green iguana and contributes to the limited knowledge of cutaneous neoplasms in green iguanas.The Wellcome Trusthttps://www.sciencedirect.com/journal/topics-in-companion-animal-medicinehj2022Centre for Veterinary Wildlife StudiesCompanion Animal Clinical StudiesParaclinical SciencesProduction Animal Studie