Phenytoin toxicity: a fatal case in a dog with hepatitis and jaundice

Pheyntoin (Epanutin: Parke, Davis) is widely used for the control of chronic convulsive disorders in the dog because it exerts an anti-epileptic effect without causing general depression of the central nervous system. To our knowledge fatal cases of phenytoin sensitivity in the dog have not been reported. A case is described in which hepatitis, jaundice and death followed the administration of the drug.     

Subchronic toxicity study of tetrahydroisohumulone and hexahydroisohumulone in the beagle dog

Hops and hop extracts are approved and widely used bittering agents in the brewing of beer. During recent years, preisomerized alpha hop acids and reduced preisomerized alpha hop acids have been introduced as effective and economical bittering agents that may be added late in the brewing process. Although hops have been used for centuries, there are few studies in the literature on the safety of this ingredient. The study herein was conducted to determine the effects associated with subchronic oral administration of the reduced preisomerized hop acids, hexahydroisohumulone and tetrahydroisohumulone, in the dog. The results show that these materials are generally well tolerated in the dog. At high dose levels they induce vomiting, and much of the material administered was excreted in the faeces. The no-observed-adverse-effect level (NOAEL) of the compounds were 50 and 100 mg/kg body weight, respectively. Consumption of these ingredients by adult humans drinking 1 litre of beer daily is less than 0.25 mg/kg body weight; their use is thus associated with wide safety margins.     

Hepatoblastoma in a dog

BACKGROUND: In neonates and infants epicardial stimulation may be preferred to endocardial stimulation because of growth-associated lead problems and the risk of vascular complications associated with transvenous electrodes. This study analyzes the feasibility of atrioventricular implantation of a new epicardial lead using the video-assisted thoracic surgical (VATS) technique in an animal model. METHODS: Bipolar steroid-eluting epicardial leads were implanted in seven young white pigs. In five animals bipolar atrial and ventricular pacing leads (n = 10) were inserted and fixed by the VATS technique, while two animals served as controls and underwent implantation through anterolateral thoracotomy. Surgical feasibility, pacing, and sensing thresholds of the leads as well as hemodynamic parameters during pacing were studied. Histological changes beneath the electrodes were evaluated 1 week after the implantation. RESULTS: All animals survived the pacemaker lead implantation. One animal which underwent thoracotomy died because of irreversible ventricular fibrillation induced by rapid ventricular pacing. One animal in the VATS group exhibited intraoperative herniation of the heart through the pericardial window. All animals with left-sided VATS implantations demonstrated good individual pacing and sensing threshold values. The mean cardiac output was 1.6 times higher during AAI-mode pacing as compared to VVI-mode pacing at a heart rate of 140/min. One animal died postoperatively due to respiratory failure. No displacements of the pacemaker leads were observed in the survivors. CONCLUSION: While VATS-guided implantation of epicardial, atrial, and ventricular leads is feasible, technical improvements of the system are mandatory for safe clinical application.     

Pseudorabies in a dog

Pseudorabies was diagnosed in a 5-year-old female crossbred dog by histologic examination and virus isolation. The clinical signs were depression, salivation, head pressing, and emesis. There were no gross pathologic findings. The microscopic findings in the brain stem consisted of mononuclear cell infiltrates in the leptomeninges, subarachnoid space, and neuropil. In addition, there were mononuclear cell perivascular cuffs, focal areas of gliosis, neuronal degeneration, and acidophilic intranuclear inclusions in neurons and astrocytes. Other microscopic findings were edema of lungs and fatty change in the liver. The virus was isolated from the brain and tonsils and identified by fluorescent antibody technique. Pseudorabies virus was isolated from pigs on the farm.     

Compound odontoma in a dog

Compound odontomas are rare tumors of dental origin. Though benign, their effect as a space occupying lesion can be dramatic. A large compound odontoma in the caudal right mandible of a five and a half month old dog was managed by surgical enucleation of the abnormal tissues. No recurrence was evident 6 months later.     

Closantel intoxication in a dog

A case of overdosage with closantel, a salicynalide derivative, in a dog is described. The dog received 6 times the recommended dosage. Closantel induced optic neuritis, retinal degeneration, partial deafness, hepatotoxicosis and myopathy. Only the blindness was irreversible. The therapy included albumin administration to reduce the acute toxicity of closantel.     

Atrial adipofibrosis in a dog

Recent studies in healthy controls suggest an association between novelty-seeking (NS) and the dopamine D4 receptor (DRD4) gene. In this study, we further investigated the relationship between genes implicated in dopamine as well as serotonin neurotransmission and personality traits in bipolar (BP) disorder. Scores on the Tridimensional Personality Questionnaire were examined in 37 recovered Research Diagnostic Criteria-diagnosed BP patients genotyped for DRD3, DRD4, and serotonin 2A receptor (5HTR2a) polymorphisms. Carriers of DRD3 allele 1 showed significantly lower NS values compared to patients without this allele. Scores on NS and on harm-avoidance were not related to DRD4 or 5HTR2a polymorphisms. These preliminary results suggest a role for D3 receptor in NS expression in BP patients.     

Lead poisoning in a dog

A case of lead poisoning caused by ingestion of a lead roof-washer is described in a one-year-old, spayed Fox Terrier bitch, presented with nervous signs, and basophilic stippling of red blood cells. Blood concentrations of lead were in the low toxic range. Radiography of the abdomen revealed radio-dense objects in the stomach, which on gastrotomy included a lead roof-washer. Prior to removal of the foreign bodies, the dog showed remarkable improvement on non-specific symptomatic treatment alone, and recovered well after surgery, only to die unexpectedly several hours later. Concentrations of lead in the liver and kidneys were extremely high, and histology revealed typical intracellular inclusions and organ degeneration. In the light of these findings, it is suggested that all cases of suspected or confirmed lead poisoning be given specific chelation therapy.     

Cyanide toxicity and thiosulfate protection during chronic administration of sodium nitroprusside in the dog: correlation with a human case

Three adult spayed female hunting dogs had an unusual form of chronic active gastritis. The disease lasted for months to several years. Vomiting was the most consistent clinical sign. One dog had leukocytosis with 30 percent eosinophils. The stomach of each dog was enlarged and greatly thickened. Collagen deposits, granulation tissue and eosinophils replaced most of the gastric wall. Disease of the gastric arteries ranged from fibrinoid necrosis to panarteritis. Granulation tissue obstructed the omental arteries of one dog. There also was splenic reticuloendothelial hyperplasia with fibrosis, hemorrhage and congestion, and chronic eosinophilic lymphadenitis. Although the cause of this disease was not determined, its basis probably was immunologic.     

Aneurysmal bone cyst in a dog

A one-year-old male mongrel dog was referred to the Veterinary Clinic with a several-week history of lameness and pain of the right front leg. Radiological examination of the right humerus revealed a cystic lesion at the distal end of the bone; the lesion was nodular in a gross appearance. Histologically, the nodular lesion consisted of large areas of haemorrhage and thick fibrous trabeculae mixed with a variably dilated cavernous structure of blood vessels attributed to haemangiosarcoma. Based on these findings, aneurysmal bone cyst secondary to the tumour was diagnosed.     

Chronic caecal faecolithiasis in a dog

A 14-year-old, spayed female Jack Russell terrier with a six month history of weight loss, lethargy, intermittent vomition and diarrhoea was diagnosed as having a chronic impaction of the caecum with mineralised faecal material. Diagnosis was based on the clinical findings and both survey and positive contrast radiographic studies. The diagnosis of caecal impaction was confirmed at surgery and a typhlectomy was performed with the aid of a linear stapler. Histopathology of the caecum confirmed the impaction to have resulted from faecolithiasis. The dog made a full recovery from the procedure, showing no recurrence of the clinical signs until euthanasia three months postoperatively for probable heart failure associated with mitral regurgitation.     

Bilateral xanthine nephrolithiasis in a dog

Xanthinuria is an uncommon metabolic disorder clinically manifested as urolithiasis. There are two forms of the disease, congenital and iatrogenic. The former was diagnosed in a four-year-old dachshund bitch. The patient was presented with signs of terminal chronic renal failure. Urine was bacteriologically sterile with massive amorphous crystalluria. Bilateral nephrolithiasis was diagnosed at necropsy. The kidneys were shrunken with marked atrophy of the renal cortex and medulla. Infrared spectrometry revealed that the stones comprised 100 per cent xanthine. Later, two of the patient's siblings were examined for urine xanthine content; both showed higher concentrations of xanthine than a control dog. The described case is compared with seven known published cases of congenital xanthinuria.