Retrospective Study: Cause and clinical characteristics of rib fractures in cats: 33 cases (2000–2009)

Objective – To characterize the clinical features and population differences among cats sustaining traumatic and nontraumatic rib fractures. Design – Retrospective clinical study. Setting – University small animal hospital. Animals – Thirty‐three cats with radiographic evidence of rib fractures. Interventions – None. Measurements and Main Results – Cats with rib fractures were identified by performing a computer search of the radiology database. Thirty‐three cats that sustained rib fractures were identified between January 2000 and September 2009. Seventeen cats had fractures due to trauma and 16 were deemed to occur from nontraumatic causes. A Mann‐Whitney rank‐sum test revealed statistically significant differences in the median ages between the 2 groups. Older cats were more likely to sustain rib fractures as a result of a presumed nontraumatic causes. A Chi‐square analysis showed that nontraumatic fractures occurred significantly more often in the midbody region and involved the 9th–13th ribs. The majority of cats with presumed nontraumatic rib fracture had respiratory disease; the remaining cats had chronic renal disease or neoplasia. Cats with traumatic rib fractures had external signs of trauma. Conclusion – Rib fractures in cats may be clearly associated with trauma, or may be an incidental finding in cats with comorbidities. Cats with diseases that cause prolonged respiratory effort or coughing, metabolic diseases, or certain neoplasms, are at increased risk of spontaneous nontraumatic rib fractures.     

Chronic lymphocytic leukaemia in the cat: 18 cases (2000–2010)

There is little information regarding the presentation, biologic behaviour, treatment and prognosis in cats with chronic lymphocytic leukaemia (CLL), and further investigation is needed to characterize this disease in cats. The goal of this study was to describe the clinical presentation, response to treatment and prognosis of feline CLL. A multi‐institutional retrospective study of 18 cats diagnosed with CLL between 2000 and 2010 was performed. CLL was defined as the presence of a mature lymphocytosis (> 9000 lymphocytes µL^?1) and confirmation of an immunophenotypically monomorphic or clonal lymphoid population. Each patient was required to also have at least one of the two following criteria: (1) concurrent cytopenia of at least one cell line and/or (2) >15% mature lymphocytes in the bone marrow. Data on signalment, history, clinical signs, clinicopathologic features and response to treatment were reviewed. Median age of the cats at initial presentation was 12.5 years (range: 5–20 years). The most common presenting complaint was chronic weight loss, which was present in 8/18 (44%) cats. Sixteen of 18 (89%) cats were treated with chlorambucil and prednisolone; four of these cats also received vincristine. Two (11%) cats were treated with multi‐agent injectable chemotherapy (L‐CHOP, l ‐asparaginase, cyclophosphamide, doxorubicin, vincristine, prednisolone). Eighty‐eight percent of cats evaluable for response achieved a complete (nine cats) or partial (six cats) remission. Median overall remission was 15.7 months (range: 1.3–22.8 months). The median overall survival in the 17 cats with follow‐up data was 14.4 months (range: 0.9–25.3 months). Results of this study suggest that CLL affects older‐aged cats and responds favourably to treatment with oral chlorambucil and prednisolone.     

The usefulness of immunohistochemistry to differentiate between nasal carcinoma and lymphoma in cats: 140 cases (1986–2000)

A retrospective evaluation of 232 feline nasal biopsies initially diagnosed as either carcinoma or lymphoma was performed by two pathologists. One or both pathologists disagreed with the original diagnosis in 15 cases (7%), 14 of which had original diagnoses of carcinoma. Out of the 232 cases, 140, including the disputed ones, were subjected to immunohistochemical staining with epithelial and lymphoid markers. Immunohistochemical staining of the 15 disputed cases showed that the original diagnoses were incorrect in 67% (10/15), unverified in 13% (2/15) and correct in 20% (3/15). Among the consensual diagnoses, immunohistochemistry revealed that 3% (4/125) of diagnoses were unverified because they did not stain for any of the markers evaluated. This report demonstrates the importance of immunohistochemistry in establishing a correct histologic diagnosis for nasal neoplasms in cats.     

Potpourri oil toxicity in cats: 6 cases (2000–2007)

Objective – To describe the clinical and laboratory features, treatment, and outcome of cats with a history of potpourri oil exposure. Design – Retrospective study. Setting – Veterinary teaching hospital. Animals – Six client‐owned cats. Measurements and Main Results – The medical records of animals with oral or lingual ulceration and exposure to potpourri oil from January 2000 to December 2007 were reviewed. Information obtained from the medical records included signalment, product to which the animal was exposed, clinical signs, physical examination findings, diagnostic test results, treatment, duration of hospitalization, and outcome. Six cats qualified for inclusion in the study; 3 were castrated males and 3 were spayed females. Age range was 0.3–3.6 years. All cats had severe oral and lingual ulceration. Additional clinical findings included hyperthermia, tachypnea, ptyalism, and lethargy. Treatment of these cats included IV fluids, analgesic therapy, antimicrobial therapy, and gastrointestinal protectants. Two of these cats received an esophagostomy tube for nutritional support. Duration of hospitalization was 0–5 days. All cats survived to discharge. Follow‐up for 3 cats revealed complete healing of the oral ulceration. Conclusions – Potpourri oil toxicity should be considered as a differential diagnosis in any cat with oral and lingual ulceration. Prognosis for recovery is good with supportive care.     

Comparison of regular insulin infusion doses in critically ill diabetic cats: 29 cases (1999–2007)

Objective – To compare biochemical parameters, neurologic changes, length of hospital stay, and clinical improvement in 3 groups of cats with diabetic ketosis/diabetic ketoacidosis (DK/DKA) prescribed varied doses of regular insulin as a continuous rate of infusion (CRI). Design – Retrospective study. Setting – University teaching hospital. Animals – Twenty‐nine client‐owned cats with DK/DKA prescribed a regular insulin CRI. Interventions – Cats were grouped as follows: 7 cats each in Group 1 and 2, (prescribed 1.1 and 2.2 U/kg/d, respectively), and 15 cats in Group 3 (prescribed increasing doses as needed). Measurements and Main Results – None of the groups received the total prescribed dose of insulin. The mean actual dose administered/kg/d ranged from 0.30 (0.21) to 0.87 (0.32) U/kg/d in Groups 1, 2, and 3. There was no difference in mean minimum blood glucose (BG) per 4 hours or change in BG from baseline per 4 hours between Groups 1 and 2 (P=0.63, 0.50). There was no difference between groups regarding the time required to reach a BG ≤13.9 mmol/L (250 mg/dL), serum phosphorus or potassium concentrations relative to baseline values (P=0.53, 0.90), length of time until urine or serum ketones were no longer detected (P=0.73), the animal commenced eating (P=0.24), or length of hospital stay (P=0.63). Four of the cats had declining mentation during hospitalization; there were no relationships between osmolality at presentation, either prescribed or administered insulin dose, and mentation changes. Three of the 4 cats with declining mentation survived. Twenty‐seven of the 29 cats (93%) survived to discharge. Conclusions – In this study, prescribing the published canine dose (2.2 U/kg/d) of regular insulin to cats with DK/DKA does not appear to increase the frequency of adverse neurologic or biochemical sequelae compared with cats that are prescribed the published cat dose (1.1 U/kg/d). The use of a sliding scale for determination of infusion rates significantly reduces the amount of insulin cats receive in this setting. Determination of whether adverse sequelae would occur more frequently if cats with DK/DKA received the full insulin prescribed doses of 1.1, 2.2, or >2.2 U/kg/d is warranted. Further controlled studies are necessary to determine if higher doses of insulin are associated with beneficial effects on morbidity or mortality.     

Retrospective Study: Surgical intervention in the management of severe acute pancreatitis in cats: 8 cases (2003–2007)

Objective – To evaluate clinical characteristics and outcomes of cats undergoing surgical intervention in the course of treatment for severe acute pancreatitis. Design – Retrospective observational study from 2003 to 2007 with a median follow‐up period of 2.2 years (range 11 d–5.4 y) postoperatively. Setting – Private referral veterinary center. Animals – Eight cats. Interventions – None. Measurements and Main Results – Quantitative data included preoperative physical and clinicopathologic values. Qualitative parameters included preoperative ultrasonographic interpretation, perioperative and intraoperative feeding tube placement, presence of free abdominal fluid, intraoperative closed suction abdominal drain placement, postoperative complications, microbiological culture, and histopathology. Common presenting clinical signs included lethargy, anorexia, and vomiting. Leukocytosis and hyponatremia were present in 5 of 8 cats. Hypokalemia, increased total bilirubin, and hyperglycemia were present in 6 of 8 cats. Elevated alanine aminotransferase and aspartate transferase were present in all cats. Surgery for extrahepatic biliary obstruction was performed in 6 cats, pancreatic abscess in 3 cats, and pancreatic necrosis in 1 cat. Six of the 8 cats survived. Five of the 6 cats that underwent surgery for extrahepatic biliary obstruction and 1 cat that underwent pancreatic necrosectomy survived. All 5 of the cats with extrahepatic biliary obstruction secondary to pancreatitis survived. The 2 nonsurvivors included a cat with a pancreatic abscess and a cat with severe pancreatitis and extrahepatic biliary obstruction secondary to a mass at the gastroduodenal junction. Postoperative complications included progression of diabetes mellitus, septic peritonitis, local gastrostomy tube stoma inflammation, local gastrostomy tube stoma infection, and mild dermal suture reaction. Conclusion – Cats with severe acute pancreatitis and concomitant extrahepatic biliary obstruction, pancreatic necrosis, or pancreatic abscesses may benefit from surgical intervention. Cats with extrahepatic biliary obstruction secondary to severe acute pancreatitis may have a good prognosis.