Bacteria associated with pyothorax of dogs and cats: 98 cases (1989-1998)

OBJECTIVE: To determine the organisms most commonly isolated from pleural fluid from dogs and cats with pyothorax. DESIGN: Retrospective study. ANIMALS: 51 dogs and 47 cats. PROCEDURE: Results of bacteriologic culture of pleural fluid samples obtained by means of thoracentesis were obtained from medical records. To obtain information on in vitro antimicrobial susceptibility of organisms commonly isolated from dogs and cats, records of all dogs and cats examined during 1998 were reviewed, and information was obtained on identity and in vitro antimicrobial susceptibility of aerobic organisms isolated from samples other than urine or urinary tract samples. RESULTS: Median ages of dogs and cats were 4 years. Bacteria were isolated from pleural fluid samples from 47 of 51 (92%) dogs and 45 of 47 (96%) cats. Obligate anaerobic bacteria were isolated from 28 dogs and 40 cats. A mixture of obligate anaerobic and facultative bacteria was isolated from 17 dogs and 20 cats. Samples from cats most often yielded a member of the nonenteric group (most commonly members of the genus Pasteurella), whereas those from dogs more often yielded a member of the family Enterobacteriaceae (most commonly E coli). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that antimicrobial agents chosen for the initial treatment of dogs and cats with pyothorax should be active against a mixture of obligate anaerobic and facultative bacteria.     

Neurologic, endocrinologic, and pathologic findings associated with large pituitary tumors in dogs: eight cases (1976-1984)

Invasive tumors of the pituitary gland were diagnosed in 8 dogs. Seven of the dogs had been treated for pituitary-dependent hyperadrenocorticism before the onset of neurologic signs. All 8 dogs had behavior abnormalities and similar neurologic signs: 6 dogs had rotary nystagmus and 7 dogs had symmetric tetraparesis. Once neurologic signs developed, the clinical course in all 8 dogs had a mean duration of 4.7 +/- 2.0 months before death or euthanasia; 5 dogs had a clinical course of less than or equal to 2 months. Necropsy was performed in 7 dogs. The histologic diagnosis was malignant pituitary adenocarcinoma in 2 dogs and pituitary adenoma in 5 dogs.     

Drug-associated aplastic anemia in dogs: eight cases (1984-1988)

Records of 8 dogs with drug-associated aplastic anemia were reviewed. Drugs suspected as being causative included estradiol cyclopentylpropionate (3 dogs), phenylbutazone (2 dogs), meclofenamic acid (1 dog), trimethoprim-sulfadiazine and fenbendazole (1 dog), and quinidine (1 dog). Five of the dogs died or were euthanatized. One dog with estrogen-associated aplasia recovered after prolonged treatment. The dogs with trimethoprim-sulfadiazine and quinidine-associated marrow aplasia recovered promptly after treatment was discontinued.     

Primary hyperparathyroidism in cats: seven cases (1984-1989).

The medical records of 7 hypercalcemic cats with primary hyperparathyroidism were evaluated. Mean age was 12.9 years, with ages ranging from 8 to 15 years; 5 were female; 5 were Siamese, and 2 were of mixed breed. The most common clinical signs detected by owners were anorexia and lethargy. A cervical mass was palpable in 4 cats. Serum calcium concentrations were 11.1 to 22.8 mg/dl, with a mean of 15.8 mg/dl calculated from each cat's highest preoperative value. The serum phosphorus concentration was low in 2 cats, within reference limits in 4, and slightly high in 1 cat. The BUN concentration was greater than 60 mg/dl in 2 cats, 31 to 35 mg/dl in 2 cats, and less than 30 mg/dl in 3 cats. Abnormalities were detected in serum alanine transaminase, aspartate transaminase, and alkaline phosphatase activities from 2 or 3 cats. Parathormone (PTH) concentrations were measured in 2 cats before and after surgery. The preoperative PTH concentration was within reference limits in 1 cat and was high in 1 cat. The PTH concentrations were lower after surgery in both cats tested. A solitary parathyroid adenoma was surgically removed from 5 cats, bilateral parathyroid cystadenomas were surgically resected in 1 cat, and a parathyroid carcinoma was diagnosed at necropsy in 1 cat. None of the cats had clinical problems with hypocalcemia after surgery, although 2 cats developed hypocalcemia without tetany, one of which was controlled with oral administration of dihydrotachysterol and the other with oral administration of 1,25 dihydroxyvitamin D. All 5 of the cta that underwent removal of an adenoma were alive at least 240 days after surgery.(ABSTRACT TRUNCATED AT 250 WORDS)     

Nonsteroidal anti-inflammatory drug toxicosis in dogs and cats: 240 cases (1989-1990)

A search of medical records at the Georgia Animal Poison Information Center over a 19-month period revealed 240 cases of dog and cat exposure to nonsteroidal anti-inflammatory drugs (NSAID). The most common NSAID consumed were ibuprofen, acetaminophen, aspirin, and indomethacin. The most common clinical signs of toxicosis were vomiting and diarrhea, CNS depression, and circulatory manifestations. Pets are at risk from NSAID toxicosis through administration by the owners or accidental consumption of improperly stored drugs.     

Focal necrotizing granulomatous panniculitis associated with subcutaneous injection of rabies vaccine in cats and dogs: 10 cases (1988-1989)

Twenty-three biopsy specimens were diagnosed as injection-site reactions by the Laboratory of Pathology of the University of Pennsylvania between September 14, 1988 and June 26, 1989. Historical information about 10 animals from which biopsy specimens were obtained was acquired through written questionnaires sent to veterinarians. Eight cats and 2 dogs had been injected in the subcutis with rabies vaccine or rabies vaccine combined with other vaccines approximately 2 weeks to 2 months prior to appearance of the lesion. All lesions were well-circumscribed, firm, subcutaneous masses that had a zone of central necrosis, with peripheral infiltration by macrophages, and variable numbers of lymphocytes, plasma cells, and eosinophils. Although most biopsy lesions sites healed after a few weeks, intramuscular rabies vaccination seems preferable until a less pathogenic, subcutaneously administered vaccine is available.     

Clinical features and outcome in dogs and cats with obsessive-compulsive disorder: 126 cases (1989-2000)

OBJECTIVE: To determine clinical features and outcome in dogs and cats with obsessive-compulsive disorder (OCD). DESIGN: Retrospective study. ANIMALS: 103 dogs and 23 cats. PROCEDURES: Records of patients with OCD were analyzed for clinical features, medication used, extent of behavior modification, and outcome. RESULTS: Most dogs affected with OCD had been obtained from breeders. Male dogs significantly outnumbered females (2:1). Female cats outnumbered male cats by 2:1 in a small sample. Most affected dogs lived in households with 2 or more humans and other dogs or cats, and had some formal training. Client compliance with behavior modification was high. A combination of behavior modification and medication resulted in a large decrease in intensity and frequency of OCD in most animals. Clomipramine was significantly more efficacious for treatment in dogs than was amitriptyline. Only 1 dog and 1 cat were euthanatized because of OCD during the study. CONCLUSIONS AND CLINICAL RELEVANCE: OCD in dogs does not appear to be associated with lack of training, lack of household stimulation, or social confinement. In cats, OCD may be associated with environmental and social stress. Obsessive-compulsive disorder appears at the time of social maturity and may have sporadic and heritable forms. With appropriate treatment (consistent behavior modification and treatment with clomipramine), frequency and intensity of clinical signs in most dogs and cats may decrease by > 50%. Success appears to depend on client understanding and compliance and the reasonable expectation that OCD cannot be cured, but can be well controlled.     

Results of excision of thymoma in cats and dogs: 20 cases (1984-2005)

OBJECTIVE: To provide long-term follow-up information for a series of dogs and cats with invasive and noninvasive thymomas treated by excision alone. DESIGN: Retrospective case series. ANIMALS: 9 cats and 11 dogs with thymoma. PROCEDURES: Medical records were reviewed. The following factors were analyzed for their effect on prognosis: age of dog or cat, invasiveness of the tumor, percentage of lymphocytes in the mass (percentage lymphocyte composition) on histologic evaluation, and mitotic index of the mass. RESULTS: All patients were treated with excision of the tumor alone. Median overall survival time for the cats was 1,825 days, with a 1-year survival rate of 89% and a 3-year survival rate of 74%. Median overall survival time for the dogs was 790 days, with a 1-year survival rate of 64% and a 3-year survival rate of 42%. Recurrence of thymoma was observed in 2 cats and 1 dog, and a second surgery was performed in each, with subsequent survival times of 5, 3, and 4 years following the first surgery. Percentage lymphocyte composition of the mass was the only factor that was significantly correlated with survival time; animals with a high percentage of lymphocytes lived longer. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study indicated that most cats and dogs with thymomas did well after excision. Even cats and dogs with invasive masses that survived the surgery and the few cats and dogs with recurrent thymomas or paraneoplastic syndromes had a good long-term outcome. Excision should be considered an effective treatment option for dogs and cats with thymomas.     

Chylothorax in cats: 37 cases (1969-1989)

Case records of 37 cats with chylothorax examined at 2 institutions were retrospectively evaluated. Dyspnea and coughing were the most common abnormalities noticed by the owners, and most cats were dyspneic on initial examination. There was no statistically significant difference in the gender distribution of cats studied when compared with reference populations; however, purebred cats appeared to be overrepresented in the study population. Four of the cats had unilateral pleural effusion (2 left side, 2 right side) and 9 cats had effusions that were primarily, but not exclusively, on the right side. Surgery was performed on 20 cats. Fifteen cats underwent thoracic duct or cisterna chyli ligation; 20% had complete resolution of pleural fluid. There was no significant difference in the survival rate of cats that underwent thoracic duct ligation and those that were treated by other means. Six cats had mesenteric lymphangiography performed; 2 cats had normal results, and the remainder had various degrees of thoracic lymphangiectasia. Two cats in which pleuroperitoneal shunts were placed and 2 of 3 cats that underwent pleurodesis were euthanatized or died after surgery.     

Enteral feeding of dogs and cats: 51 cases (1989-1991).

Feeding commercial enteral diets to critically ill dogs and cats via nasogastric tubes was an appropriate means for providing nutritional support and was associated with few complications. Twenty-six cats and 25 dogs in the intensive care unit of our teaching hospital were evaluated for malnutrition and identified as candidates for nutritional support via nasogastric tube. Four commercial liquid formula diets and one protein supplement designed for use in human beings were fed to the dogs and cats. Outcome variables used to assess efficacy and safety of nutritional support were return to voluntary food intake, maintenance of body weight to within 10% of admission weight, and complications associated with feeding liquid diets. Sixty-three percent of animals experienced no complications with enteral feedings; resumption of food intake began for most animals (52%) while they were still in the hospital. Weight was maintained in 61% of the animals (16 of 26 cats and 15 of 25 dogs). Complications that did occur included vomiting, diarrhea, and inadvertent tube removal. Most problems were resolved by changing the diet or adhering to the recommended feeding protocol. Nutritional support as a component of therapy in small animals often is initiated late in the course of the disease when animals have not recovered as quickly as expected. If begun before the animal becomes nutrient depleted, enteral feeding may better support the animal and avoid serious complications.     

Clinicopathologic findings associated with chronic renal disease in cats: 74 cases (1973-1984)

The historic, physical, laboratory, and histologic findings for 74 cats with chronic renal disease were reviewed. Most cats were older, and no breed or sex predilection was detected. This most common clinical signs detected by owners were lethargy, anorexia, and weight loss. Dehydration and emaciation were common physical examination findings. Common laboratory findings were nonregenerative anemia, lymphopenia, azotemia, hypercholesterolemia, metabolic acidosis, hyperphosphatemia, and isosthenuria. The most common morphologic diagnosis was chronic tubulointerstitial nephritis of unknown cause. The other pathologic diagnoses were renal lymphosarcoma, renal amyloidosis, chronic pyelonephritis, chronic glomerulonephritis, polycystic renal disease, and pyogranulomatous nephritis secondary to feline infectious peritonitis.     

Pyometra in cats: 183 cases (1979-1984)

Pyometra was diagnosed in 183 cats. The most common signs detected by owners included vaginal discharge, anorexia, and lethargy. Main clinical findings on physical examination were vaginal discharge, abdominal distention, dehydration, palpable uterus, and pyrexia. Abdominal radiography revealed a large uterus in 138/169 cats. Most cats had leukocytosis with a left shift. Diagnosis of pyometra was confirmed at surgery in all cats on the basis of finding a large uterus containing purulent material. Clinical signs resolved in 168 cats after surgery; 15 cats (8%) died or were euthanatized. Postoperative complications in 20% generally resolved within 2 weeks after the cats were sent home. Signs detected by owners and results of physical examination in cats with pyometra were similar, but not as conspicuous as those reported in the dog. Mortality (8%) was similar to that seen in dogs.     

Osteosarcoma in cats: 22 cases (1974-1984)

Osteosarcoma was diagnosed in 22 cats. Diagnosis was based on results of physical, radiographic, and histologic findings. Fifteen tumors arose from the appendicular skeleton, 4 from the skull, 2 from the pelvis, and 1 from a rib. Radiography revealed that in 14 of 15 cats (93%) with appendicular tumors, the lesion was metaphyseal, primarily lytic, with a "moth-eaten" appearance; absence and presence of periosteal new bone formation were associated with the tumors in 12 and 3 cats, respectively. The remaining 7 cats had axial tumors that were characterized by the presence of periosteal new bone formation in addition to bony lysis. Of the 15 cats with appendicular tumors, 12 were treated by amputation and 3 were euthanatized at the time of diagnosis. Of the cats undergoing amputation for treatment of their appendicular tumors, 6 cats were still alive 64 months after surgery (range, 13 to 64 months); the median survival time of the 5 cats (1 cat was lost to follow-up evaluation) that died was 49.2 months (range, 1 to 122 months). Four of 12 cats (33%) survived greater than or equal to 5 years after diagnosis. Of the cats with axial tumors that were not euthanatized at the time of diagnosis (6 of 7), the median survival time was 5.5 months. Based on these findings, we concluded that cats with appendicular osteosarcoma have a better prognosis than those with axial osteosarcoma, and that amputation is a viable treatment for cats with appendicular osteosarcoma.     

Hypokalemia in cats: 186 cases (1984-1987)

Retrospective review of serum biochemical data obtained from 501 cats over a 3-year period (1984-1987) indicated that 186 (37%) had hypokalemia (serum potassium concentration less than 4.1 mEq/L). After adjusting for disease diagnosis, cats fed either of 2 commercial diets were 4 times more likely to be hypokalemic than cats fed other diets. Odds ratios (OR; measure of association), adjusted for diet type, were calculated to determine the odds of hypokalemia for a given disease, compared with odds of normokalemia for the same disease. Chronic renal failure (OR = 14.4), hepatic disease (OR = 5.7), systemic infectious diseases (viral or bacterial; OR = 2.7), and neuromuscular or CNS disease (OR = 2.4) were all significantly associated (P less than 0.05) with the occurrence of hypokalemia. Significant differences in age or sex between hypokalemic and normokalemic cats were not found. Within the group of 186 hypokalemic cats, hypercholesterolemia (89 cats; 48%), hyperglycemia (88 cats; 47%), high serum urea nitrogen concentration (86 cats; 46%), hyperchloridemia (80 cats; 43%), and high serum creatinine concentration (73 cats; 39%) were the most common biochemical abnormalities. When disease diagnosis was compared among cats with severe hypokalemia (serum potassium concentration less than 3.0 mEq/L) and those with moderate hypokalemia, cats with severe hypokalemia were 3.5 times more likely to have chronic renal failure than cats with less severe hypokalemia.(ABSTRACT TRUNCATED AT 250 WORDS)     

Clinical findings associated with prairie rattlesnake bites in dogs: 100 cases (1989-1998)

OBJECTIVE: To identify clinically relevant variables and treatments for dogs bitten by prairie rattlesnakes (Crotalus viridis viridis). DESIGN: Retrospective study. ANIMALS: 100 client-owned dogs. PROCEDURE: Records of dogs evaluated for rattlesnake envenomation from 1989 to 1998 were reviewed. Analysis was performed to test for significant associations among clinical variables or treatments and cell counts, costs, and duration of hospitalization. RESULTS: Most prairie rattlesnake bites occurred between May and September. Dogs were 3 months to 12 years old (median, 3.7 years); most were bitten on the head in the late afternoon. There was no sex predilection. Median time to evaluation was 1 hour (range, 15 minutes to 13 hours). Swelling in the area of the bite was the primary physical abnormality. Principal initial laboratory findings were echinocytosis, thrombocytopenia, leukocytosis, and prolonged activated clotting time. Ninety-four dogs were hospitalized; 48 were discharged the following day. Antimicrobials and crystalloid fluids, glucocorticoids, antihistamines, and antivenin administered i.v. were the most commonly used treatments. One dog died, and small dogs were hospitalized longer than large dogs. Antivenin administration was not significantly associated with duration of hospitalization but was associated with higher platelet counts after treatment and higher total hospital costs. CONCLUSIONS AND CLINICAL RELEVANCE: Prairie rattlesnake envenomation in dogs is associated with high morbidity rate but low mortality rate. The efficacy of administration of antivenin for dogs with bites from this snake species is questionable.     

Liposarcomas in dogs: 56 cases (1989-2000)

OBJECTIVE: To determine the biological behavior of liposarcomas in dogs and identify clinical signs, the effect of treatment on survival time, and potential prognostic factors. DESIGN: Retrospective study. ANIMALS: 56 dogs with histologically confirmed liposarcoma. PROCEDURE: Information was obtained on signalment, tumor size, location of the tumor, stage of disease, remission duration, overall survival time, cause of death, type of surgery (incisional biopsy, marginal excision, or wide excision), and any additional treatments given. RESULTS: Surgery consisted of incisional biopsy in 6 dogs, marginal excision in 34, and wide excision in 16. Twenty-five dogs had histologic evidence of tumor cells at the surgical margins and 28 did not (status of the margins was unknown in 3 dogs). Twelve of 43 dogs had local recurrence. Median survival time was 694 days, and the only factor significantly associated with survival time was type of surgery performed. Median survival times were 1,188, 649, and 183 days, respectively, for dogs that underwent wide excision, marginal excision, and incisional biopsy. Factors that were not found to be significantly associated with survival time included tumor size, status of the margins, tumor location, and histologic subtype. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that in dogs, liposarcomas are locally invasive neoplasms that rarely metastasize and occur primarily in appendicular or axial locations and that wide excision is preferred to marginal excision when feasible.     

Acute postretinal blindness: ophthalmologic,neurologic, and magnetic resonance imaging findings in dogs and cats (seven cases)

Objective To describe the ophthalmologic, neurologic, and magnetic resonance imaging (MRI) findings of seven animals with acute postretinal blindness as sole neurologic deficit. Methods Medical records were reviewed to identify dogs and cats with postretinal blindness of acute presentation, that had a cranial MRI performed as part of the diagnostic workup. Only animals lacking other neurologic signs at presentation were included. Complete physical, ophthalmic, and neurologic examinations, routine laboratory evaluations, thoracic radiographs, abdominal ultrasound, electroretinography, and brain MRI were performed in all animals. Cerebrospinal fluid analysis and postmortem histopathologic results were recorded when available. Results Four dogs and three cats met the inclusion criteria. Lesions affecting the visual pathways were observed on magnetic resonance (MR) images in six cases. Location, extension, and MRI features were described. Neuroanatomic localization included: olfactory region with involvement of the optic chiasm (n = 4), pituitary fossa with involvement of the optic chiasm and optic tracts (n = 1), and optic nerves (n = 1). Of all lesions detected, five were consistent with intracranial tumors (two meningiomas, one pituitary tumor, two nasal tumors with intracranial extension), and one with bilateral optic neuritis that was confirmed by cerebrospinal fluid analysis. Histologic diagnosis was obtained in four cases and included one meningioma, one pituitary carcinoma, one nasal osteosarcoma, and one nasal carcinoma. Conclusions Central nervous system (CNS) disease should be considered in dogs and cats with acute blindness, even when other neurologic deficits are absent. This study emphasizes the relevance of MRI as a diagnostic tool for detection and characterization of CNS lesions affecting the visual pathways.     

Portosystemic shunts in cats: seven cases (1976-1984)

Congenital portosystemic venous shunt causing signs of hepatic encephalopathy was diagnosed in 7 cats. The left gastric vein served as the shunt in four of these. Increases in blood ammonia and postprandial serum bile acids were the most consistent serum biochemical abnormalities. Excessive variation in red blood cell shape was a common but nonspecific hematologic finding. The jejunal-mesenteric venous injection of contrast material was the preferred method of portography to diagnose portosystemic shunts. Two cats were treated successfully by partial surgical occlusion of their shunts.     

Renal lymphoma in cats: 28 cases (1977-1984)

Renal lymphoma was diagnosed, staged, and treated in 28 cats. Renal lymphoma staging was done according to clinical findings: 11 cats had stage-2 lymphomas, 5 had stage-3 lymphomas, 6 had stage-4 lymphomas, and 6 had stage-5 lymphomas. All cats were treated with chemotherapy: 17 cats had a complete response, 9 cats had a partial response, and 2 cats had no response. The cats with stage-2 lymphomas that were FeLV-test negative had the best response to treatment.     

Elective cesarean section in mares: eight cases (1980-1989)

From 1980 to 1989, 8 cesarean sections were performed on an elective basis in 5 mares. Four mares had partially obstructed pelvic canals; 2 of these mares had previously lost foals because of dystocia. Cervical adhesions that might obstruct passage of the fetus through the pelvic canal was suspected in the fifth mare. Cesarean section was performed prior to mares entering the first stage of labor. Readiness for birth was estimated by development of the mare's mammary gland and the presence of colostrum in the udder. A ventral midline celiotomy provided excellent exposure and healed without complications in all instances. Eight viable foals were produced. One foal developed bacterial pneumonia and septicemia after surgery and died. Follow-up evaluation of the 7 foals discharged from the hospital failed to reveal complications associated with elective cesarean section. All mares survived the procedure. Fetal membranes were retained for up to 72 hours following surgery; however, systemic complications secondary to retained placenta did not develop. Three mares were bred subsequent to elective cesarean sections, with each mare conceiving the year following surgery. Three foals were produced by 1 mare and 2 foals have been produced by another mare by elective cesarean sections.