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.     

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.     

Treatment and outcome of dogs with leptospirosis: 36 cases (1990-1998)

OBJECTIVE: To characterize serologic and clinical features and outcome of dogs with leptospirosis that were treated conservatively (i.e., medical management alone) or with hemodialysis. DESIGN: Retrospective study. ANIMALS: 36 dogs with leptospirosis. PROCEDURE: History; results of physical examinations, ultrasonography, and serologic, hematologic, and serum biochemical analyses; time to resolution of azotemia; and outcome were obtained from medical records. Dogs were treated conservatively (n = 22) or with hemodialysis (14). RESULTS: Between 1990 and 1998, amount of rainfall was positively correlated with number of cases of leptospirosis identified per year. Serum antibodies against 6 Leptospira serovars were measured, and titers were highest to Leptospira pomona in 16 (44%) dogs, L bratislava in 9 (25%) dogs, and L hardjo in 1 (3%) dog. Eight (22%) dogs had equally high titers to L pomona and L bratislava, 1 (3%) had equally high titers to L grippotyphosa and L canicola, and 1 (3%) had high titers to L grippotyphosa, L pomona, L canicola, and L bratislava. During initial evaluation, all dogs were azotemic. Thirty (83%) dogs survived, including 12 of 14 (86%) dogs treated with hemodialysis and 18 of 22 (82%) treated conservatively. Serum creatinine concentration was similar in both groups after resolution of clinical signs. CONCLUSIONS AND CLINICAL RELEVANCE: Infection with L pomona and L bratislava was recognized as a cause of leptospirosis in dogs, and resulted in development of acute renal failure with various degrees of azotemia. Prognosis for dogs with mild to moderate azotemia was good with conservative treatment, whereas treatment with hemodialysis appeared to improve prognosis for dogs with severe azotemia.     

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.     

Eclampsia in dogs: 31 cases (1995-1998)

OBJECTIVE: To compare clinical characteristics and laboratory findings of dogs with eclampsia with those of dogs without eclampsia. DESIGN: Retrospective study. ANIMALS: 31 dogs with eclampsia (affected) and 31 with dystocia (controls). PROCEDURE: Information on signalment, type of diet, reproductive history, litter size, time from whelping to eclampsia, body weight, clinical signs, results of physical examination and hematologic and biochemical analyses, response to calcium supplementation, and recurrence was obtained from the medical records of all dogs with eclampsia evaluated between 1995 and 1998 and compared with information from medical records of 31 of 102 dogs with dystocia evaluated during the same period. RESULTS: Dogs with eclampsia weighed less, had a smaller body weight-to-litter size ratio, higher rectal temperature and heart and respiratory rates, and lower plasma total solids concentration than control dogs. Ionized calcium concentration was < or = 0.8 mmol/L for all but 1 of the affected dogs; median concentration for the affected dogs was significantly less than that for control dogs. Six (19%) dogs did not manifest typical clinical signs associated with eclampsia. Twelve (39%) dogs with eclampsia had previous litters; none had a history of eclampsia. Affected dogs were discharged from the hospital within hours after admission, but 3 dogs returned 1 to 3 weeks later because of recurrence of eclampsia. CONCLUSIONS AND CLINICAL RELEVANCE: Eclampsia develops primarily in small-breed dogs with large litters. Plasma ionized calcium concentrations > 0.8 mmol/L in dogs with clinical signs typical of hypocalcemia may indicate that other causes of clinical signs should be considered. In addition, some dogs with eclampsia may have low ionized calcium concentrations and not manifest typical clinical signs.     

Canine hepatozoonosis: comparison of lesions and parasites in skeletal muscle of dogs experimentally or naturally infected with Hepatozoon americanum.

We report previously undescribed, early lesions in skeletal muscle of dogs experimentally infected with Hepatozoon americanum by ingestion of laboratory-reared, infected Amblyomma maculatum. The earliest muscle lesion was recognized at the first interval of examination 3 weeks following exposure. The lesion consisted of a large, modified host cell whose cytoplasm frequently contained a demonstrable parasite. In skeletal muscle, the cell was consistently located between muscle fibers or in loose connective tissue adjacent to those fibers. Evidence suggesting that the parasite arrives in muscle and other tissue within the host cell cytoplasm is presented. Mucopolysaccharide encystment of the host cell, absent at this early stage, was acquired gradually and approached maximal development 26 weeks post exposure. Completion of the asexual cycle as evidenced by the presence of parasites entering vascular lumens within granulomas and also by the presence of gamonts in peripheral blood leukocytes, occurred within 28-32 days postexposure. Progression of the parasite cycle from meront to passage of zoites into vessel lumens of granulomas can occur in 11 or fewer days. The density with which parasitic lesions occur in one named skeletal muscle compared to other named muscles, although somewhat variable, was not significantly different in either experimentally induced or natural infections. The distribution of developmental stages of the parasite/lesion in four experimental infections (969 lesions) is compared with those in eight dogs with natural infections (557 lesions).     

Causes of uveitis in dogs: 102 cases (1989-2000)

Uveitis is one of the most common ocular diseases and one of the most common causes of blindness in dogs. The purpose of this retrospective study was to correlate the signalment, history, clinical signs and ophthalmic findings of dogs with uveitis with the underlying etiology. We conducted a retrospective study of 102 dogs presented to the NCSU-VTH from 1989 to 2000 with clinical signs of uveitis. Medical records of dogs presented for uveitis were reviewed. Dogs were included in the study only if a complete diagnostic work-up database was collected, if sufficient follow-up was documented, and if the uveitis was not secondary to trauma or a hypermature cataract. The mean age +/- SD of all dogs in this study was 6.2 +/- 3.6 years. There were 33 intact and 16 castrated males, and 14 intact and 27 neutered females. Fourteen breeds were represented, with the Golden Retriever (n = 14) most common. Fifty-nine dogs (58%) were diagnosed with idiopathic/immune-mediated uveitis, neoplasia was diagnosed in 25 dogs (24.5%) and 18 dogs (17.6%) were diagnosed with infectious causes of uveitis. Aqueous flare was the most common clinical sign, occurring in 88 dogs (86%). The most common infectious organisms associated with uveitis in the dogs of this study were Ehrlichia canis (n = 7). Lymphosarcoma (n = 17) was the most common neoplasm. In approximately 60% of dogs presenting for uveitis an underlying cause was not found, and a diagnosis of immune-mediated or idiopathic uveitis was made. However, approximately 25% of dogs had ocular and/or systemic neoplasia (with 17% of cases having lymphosarcoma) and 18% with an underlying infectious cause for uveitis. Because of the high percentage of systemic disease associated with uveitis in dogs, extensive diagnostic testing is recommended before instituting symptomatic anti-inflammatory therapy.     

Radiographic findings in dogs with pulmonary blastomycosis: 125 cases (1989-2006)

OBJECTIVE: To identify radiographic patterns in dogs with pulmonary blastomycosis and radiographic factors associated with outcome. DESIGN: Retrospective case series. ANIMALS: 125 dogs with pulmonary blastomycosis. PROCEDURES: Medical records were reviewed, and for each lung lobe, the primary radiographic pattern and percentage of lobar involvement at the time of initial examination were recorded. RESULTS: 79 dogs survived, 38 died, and 8 were euthanized without treatment. The initial radiographic pattern was variable and not significantly associated with outcome. Mean half-time for radiographic resolution of pulmonary infiltrates was 41.4 days for all patterns except masses, for which mean half-time to resolution was 90.8 days. Transient radiographic worsening was seen in 20 of 87 (23%) dogs but was not associated with a poor prognosis. Pulmonary bullae were seen in 20 (16%) dogs, most often in association with an alveolar pattern. Accuracy of using percentage of right caudal lung lobe involvement ( 20%) to predict outcome was 74.4%; accuracy of using number of affected lobes (< 4 vs >or= 4) to predict outcome was 65.8%. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that a nonuniform distribution of pulmonary infiltrates was equally as likely as a diffuse nodular interstitial pattern in dogs with pulmonary blastomycosis. On the basis of half-time for resolution of pulmonary infiltrates, follow-up radiography should be performed no more often than every 4 to 6 weeks in clinically stable patients. Transient radiographic worsening that occurred during the initial weeks of treatment was not associated with a poorer prognosis.     

5-Hydroxytryptophan toxicosis in dogs: 21 cases (1989-1999)

OBJECTIVE: To determine epidemiologic characteristics, clinical findings, and treatment outcome of 5-hydroxytryptophan (5-HTP) toxicosis in dogs. DESIGN: Retrospective study. ANIMALS: 21 dogs with evidence of accidental 5-HTP ingestion. PROCEDURE: Information was retrieved from the National Animal Poison Control Center database. Records of dogs ingesting 5-HTP between January 1989 and February 1999 were reviewed for information on signalment, dose ingested, clinical signs (onset, severity, duration), treatments administered, and outcome. RESULTS: Clinical signs of toxicosis developed in 19 of 21 (90%) dogs. Neurologic signs included seizures (9 dogs), depression (6), tremors (5), hyperesthesia (5), and ataxia (4). Gastrointestinal tract signs included vomiting or diarrhea (12 dogs), signs of abdominal pain (3), and hypersalivation (2). Other clinical signs were hyperthermia (7 dogs) and transient blindness (3). Three dogs died. No important clinical laboratory or necropsy findings were reported. The doses of 5-HTP ingested ranged from 2.5 to 573 mg/kg (1.1 to 260 mg/lb) of body weight; the minimum toxic dose reported in our study was 23.6 mg/kg (10.7 mg/lb), and the minimum lethal dose was 128 mg/kg (58.1 mg/lb). Onset of signs ranged from 10 minutes to 4 hours after ingestion, and signs lasted up to 36 hours. Of 17 dogs with clinical signs of toxicosis that received treatment, 16 recovered; treatment consisted of decontamination, seizure control, thermoregulation, fluid therapy, and supportive care. CONCLUSIONS AND CLINICAL RELEVANCE: Ingestion of 5-HTP in dogs can result in a potentially life-threatening syndrome resembling serotonin syndrome in humans, which requires prompt and aggressive care.     

Concurrent disorders in dogs with diabetes mellitus: 221 cases (1993-1998)

OBJECTIVE: To characterize concurrent disorders in dogs with diabetes mellitus (DM). DESIGN: Retrospective study. ANIMALS: 221 dogs with DM. PROCEDURE: Medical records were reviewed, and clinical signs, physical examination findings, and results of clinicopathologic testing, urinalysis, aerobic bacterial culture of urine samples, coagulation testing, endocrine testing, histologic evaluation, diagnostic imaging, and necropsy were recorded. RESULTS: For most dogs, CBC results were normal. Common serum biochemical abnormalities included hypochloremia (127 dogs, 60%) and high alanine aminotransferase (163, 78%), aspartate aminotransferase (78, 71%), and alkaline phosphatase (188, 90%) activities. Venous pH and serum ionized calcium concentration were measured in 121 and 87 dogs, respectively, and were low in 56 (46%) and 41 (47%) dogs. Lipemia was observed in 92 (42%) dogs. Urine samples from 159 (72%) dogs were submitted for aerobic bacterial culture, and 34 (21%) yielded bacterial growth. Escherichia coli was the most commonly isolated organism. Thirty-six (16%) dogs had dermatitis or otitis. Hyperadrenocorticism was diagnosed in 51 (23%) dogs on the basis of clinical signs and results of a low-dose dexamethasone suppression test (41 dogs), an adrenocorticotropic hormone stimulation test (5), both tests (4), or histologic evaluation of necropsy specimens (1). Acute pancreatitis was diagnosed in 28 (13%) dogs. Eleven (5%) dogs had tumors for which a histologic diagnosis was obtained. Eight (4%) dogs were hypothyroid. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that dogs with diabetes mellitus may have many concurrent disorders. The most commonly identified concurrent disorders included hyperadrenocorticism, urinary tract infection, dermatitis, otitis, acute pancreatitis, neoplasia, and hypothyroidism.     

Bufo marinus intoxication in dogs: 94 cases (1997-1998)

OBJECTIVE: To determine history, clinical and electrocardiographic abnormalities, treatment, and outcome of dogs exposed to toxins produced by the Bufo marinus toad. DESIGN: Retrospective study. ANIMALS: 94 dogs. PROCEDURE: Medical records of dogs examined between July 1997 and July 1998 for which a diagnosis of toad intoxication had been made on the basis of history and physical examination findings were reviewed. RESULTS: Most (66) dogs were treated during the spring and summer. For 54 dogs, exposure to toads had been witnessed. For the remaining 40, toad intoxication was diagnosed on the basis of history and clinical signs. The most common clinical signs were neurologic abnormalities, hyperemic mucous membranes, ptyalism, recumbency or collapse, tachypnea, and vomiting. The oral cavity was lavaged with tap water in all dogs. Fifty-two dogs were hospitalized for treatment. Body weight of dogs hospitalized > 2 hours was significantly less than that of dogs treated as outpatients. The most common electrocardiographic findings were sinus arrhythmia, sinus tachycardia, and normal sinus rhythm. Eighty-nine dogs recovered fully, 4 died, and 1 was euthanatized. CONCLUSIONS AND CLINICAL RELEVANCE: In areas in which B marinus toads are endemic, toad intoxication should be considered in the differential diagnosis for dogs with an acute onset of neurologic abnormalities, hyperemic mucous membranes, and ptyalism, especially during the spring and summer months. The prognosis is good for dogs with toad intoxication that receive appropriate treatment.     

Femoral capital physeal fractures in dogs: 34 cases (1979-1989)

Complications associated with femoral capital physeal (CP) fractures in 34 dogs were evaluated. Fractures were surgically repaired, using divergent K-wires or lag screws; radiographic follow-up was available for 21 CP fractures. In all cases, radiographic abnormalities such as degenerative joint disease and resorption of the femoral neck and/or head were seen. Changes were more severe when fracture occurred at an early age. For 4 of 21 dogs (20%), femoral head and neck excision was performed because of complications associated with CP fracture repair. Prognosis for femoral CP fractures is guarded, although affected dogs should be able to function as pets.     

Idiopathic noncirrhotic portal hypertension in dogs: 33 cases (1982-1998)

OBJECTIVE: To describe clinical signs, diagnostic findings, and outcome in dogs with idiopathic intrahepatic portal hypertension. DESIGN: Retrospective study. ANIMALS: 33 dogs. PROCEDURE: Medical records of dogs with portal hypertension of intra-abdominal origin were reviewed. Dogs with intra-abdominal portal hypertension of vascular causes or with hepatic histopathologic changes consistent with severe diffuse hepatobiliary disease were excluded. History and results of physical examination, clinicopathologic tests, diagnostic imaging studies, histologic examination, and treatment were summarized. Outcome was determined in 26 dogs. RESULTS: Dogs were referred most often because of ascites, intermittent vomiting or diarrhea, and polydipsia of several months' duration. Microcytosis, high serum alkaline phosphatase and alanine transaminase activities, hepatic dysfunction, urine specific gravity < or = 1.021, and abdominal transudate were the predominant clinicopathologic features. Microhepatia, abdominal effusion, and multiple anomalous venous anastomoses were the major findings of diagnostic imaging. Hepatic histopathologic changes were consistent with idiopathic noncirrhotic portal hypertension and were indistinguishable from those of dogs with surgically created portocaval anastomosis. Outcome was determined for 19 dogs released from hospital; 13 dogs remained healthy with mostly palliative treatment for periods of 5 months to 9 years. CONCLUSIONS AND CLINICAL RELEVANCE: The clinical signs, clinicopathologic test results, portal pressure, and gross appearance of the liver of dogs with idiopathic noncirrhotic portal hypertension may be identical to those of dogs with cirrhosis; therefore liver biopsy is crucial. Because the prognosis for idiopathic noncirrhotic portal hypertension is generally favorable, owners of affected dogs should be discouraged from choosing euthanasia.     

Nonenteric Escherichia coli isolates from dogs: 674 cases (1990-1998)

OBJECTIVE: To determine nonenteric sites associated with Escherichia coli isolates in dogs and the antimicrobial susceptibilities of the isolates. DESIGN: Retrospective study. SAMPLE POPULATION: 17,000 canine specimens. PROCEDURE: Medical records of 17,000 canine specimens submitted for bacteriologic culture were examined and the number of isolations of E coli was determined. For these cases, records were further examined with respect to body system involvement, sex, concurrent infection with other species of bacteria, and antimicrobial susceptibility. RESULTS: 674 E coli isolates (424 from urine, 62 from the skin, 52 from the respiratory tract, 45 from the ear, 43 from the female reproductive tract, 25 from the male reproductive tract, and 23 from other organ systems) were identified. There was a significantly higher proportion of isolates from urine specimens from spayed females than from sexually intact females or males. Escherichia coli was isolated in pure culture from 65.9% of the specimens. Most E coli isolates were susceptible to norfloxacin (90%), enrofloxacin (87.5%), gentamicin (90.7%), and amikacin (85.9%). CONCLUSIONS AND CLINICAL RELEVANCE: Most nonenteric E coli infections in dogs involve the urinary tract. Amikacin, gentamicin, norfloxacin, and enrofloxacin have the highest efficacy against canine E coli isolates. For E coli isolates from dogs, in vitro susceptibility to commonly used antimicrobial agents has remained fairly stable during the past decade.     

Arthroscopic removal of patellar fracture fragments in horses: five cases (1989-1998)

OBJECTIVE: To evaluate the use of arthroscopy as the primary method for removal of large patellar fracture fragments. DESIGN: Retrospective study. ANIMALS: 5 performance horses of various breeds with patellar fractures. PROCEDURE: Clinical signs of lameness, external evidence of injury, and radiography were used to diagnose and determine fracture orientation. Arthroscopy of the stifle joint was performed on the affected limb with the horse positioned in dorsal recumbency and under general anesthesia. Progress after surgery was determined by evaluating medical records and via telephone conversations with owners. RESULTS: 4 of 5 horses had fractures of the medial aspect of the patella and 1 horse had a fracture of the lateral aspect of the patella. There were no postoperative complications with the joint or the arthroscopic portal incisions. Recovery periods ranged from 3 to 5 months. All horses recovered completely from surgery, and performed at the same or higher level of competition as before arthroscopy. CONCLUSIONS AND CLINICAL RELEVANCE: Femoropatellar joint arthroscopy is a favorable means by which evaluation of the stifle joint and removal of large fracture fragments can be achieved with negligible postoperative complications.     

Surgical management of cricopharyngeal dysphagia in dogs: 14 cases (1989-2001)

OBJECTIVE: To determine outcome of and complications associated with cricopharyngeal myotomy or myectomy for treatment of cricopharyngeal dysphagia (CPD) in dogs. DESIGN: Retrospective study. ANIMALS: 14 dogs. PROCEDURE: Medical records of dogs with CPD that underwent cricopharyngeal myotomy or myectomy were examined. Follow-up information was obtained through telephone interviews with owners and referring veterinarians and clinical examinations when feasible. RESULTS: 16 surgical procedures were performed on the 14 dogs. Dysphagia was completely resolved immediately after surgery in 1 dog, and clinical signs did not recur (follow-up time of 8 years); a second dog also had immediate complete resolution of dysphagia, but follow-up time was only 10 days. Three dogs had transient complete resolution with a mean time to recurrence of dysphagia of 12.3 weeks (range, 2 to 36 weeks). Three dogs had permanent partial resolution. Six dogs had no improvement after surgery. Eight of the 14 dogs were euthanatized because of problems related to CPD, including persistent dysphagia (n = 8) and aspiration pneumonia (5). CONCLUSIONS AND CLINICAL RELEVANCE: The failure rate for dogs undergoing surgical treatment of CPD may be high, particularly if concurrent aspiration pneumonia or malnutrition is not addressed prior to surgery. For those dogs with concurrent diseases, more aggressive medical management, such as enteral tube feeding, may be warranted rather than surgery. In dogs with CPD complicated by other anatomic or functional conditions, such as myasthenia gravis, laryngeal paralysis, and esophageal stricture, surgery may also not be indicated.     

Use of carboplatin for treatment of dogs with malignant melanoma: 27 cases (1989-2000)

OBJECTIVE: To evaluate response rate and duration of malignant melanomas in dogs treated with carboplatin. DESIGN: Retrospective study. ANIMALS: 27 client-owned dogs with spontaneously occurring measurable malignant melanomas. PROCEDURE: Records of dogs with melanomas treated with carboplatin from October 1989 to June 2000 were reviewed. Carboplatin was administered IV at doses of 300 or 350 mg/m2 of body surface area. Response to treatment and evidence of drug toxicity were determined. RESULT: Response to treatment could be evaluated in 25 dogs. Of those, overall response rate was 28%. One dog had a complete response, 6 (24%) dogs had a partial response (> 50% reduction in tumor burden). Median duration of partial response was 165 days. Eighteen dogs had stable disease (n = 9; 36%) or progressive disease (9; 36%). Response to treatment was significantly associated with carboplatin dose on a milligram per kilogram basis (15.1 mg/kg 16.9 mg/lb] of body weight vs 12.6 mg/kg [5.7 mg/lb]). Evidence of gastrointestinal toxicosis could be assessed in 27 dogs. Mean body weight of 5 dogs that developed gastrointestinal toxicosis was significantly less than that of 22 dogs without gastrointestinal toxicosis (9.9 kg [21.8 lb] vs 19.3 kg [42.5 lb]). CONCLUSIONS AND CLINICAL RELEVANCE: Carboplatin had activity against macroscopic spontaneously occurring malignant melanomas in dogs and should be considered as an adjunctive treatment for microscopic local or metastatic tumors. Gastrointestinal toxicosis was associated with body weight. Because small dogs are more likely to have adverse gastrointestinal effects, gastrointestinal protectants should be considered for these patients.     

Reliability of history and physical examination findings for assessing control of glycemia in dogs with diabetes mellitus: 53 cases (1995-1998)

OBJECTIVE: To evaluate the reliability of history and physical examination findings for assessing control of glycemia in insulin-treated diabetic dogs. DESIGN: Retrospective study. ANIMALS: 53 insulin-treated dogs with diabetes mellitus. PROCEDURE: Medical records of insulin-treated diabetic dogs from June 1995 to June 1998 were reviewed, and information on owner perception of their dog's response to insulin treatment, physical examination findings, body weight, insulin dosage, and concentrations of food-withheld (i.e., fasting) blood glucose (FBG), mean blood glucose (MBG) during an 8-hour period, blood glycosylated hemoglobin (GHb), and serum fructosamine was obtained. Owner's perception of their dog's response to insulin treatment, physical examination findings, and changes in body weight were used to classify control of glycemia as good or poor for each dog. The FBG, MBG/8 h, blood GHb, and serum fructosamine concentrations were compared between well-controlled and poorly controlled insulin-treated diabetic dogs. RESULTS: Presence or absence of polyuria, polydipsia, polyphagia, lethargy, and weakness were most helpful in classifying control of glycemia. Mean FBG and MBG/8 h concentrations, blood GHb concentrations, and serum fructosamine concentrations were significantly decreased in 25 well-controlled diabetic dogs, compared with 28 poorly controlled diabetic dogs. Most well-controlled diabetic dogs had concentrations of FBG between 100 and 300 mg/dl, MBG/8 h < or = 250 mg/dl, blood GHb < or = 7.5%, and serum fructosamine < or = 525 mumol/L, whereas most poorly controlled diabetic dogs had results that were greater than these values. CONCLUSIONS AND CLINICAL RELEVANCE: Reliance on history, physical examination findings, and changes in body weight are effective for initially assessing control of glycemia in insulin-treated diabetic dogs.     

Locked jaw syndrome in dogs and cats: 37 cases (1998-2005)

A consecutive series of cases of dogs and cats with locked jaw syndrome (inability to open or close the mouth) are reported in this study. Dogs were significantly overrepresented (84.0%) and adult dogs were more frequently affected (81.0%). Temporomandibular joint ankylosis due to fracture was the most common cause (54.0%) of locked jaw syndrome. Additional potential causes of locked jaw syndrome are masticatory muscle myositis, neoplasia, trigeminal nerve paralysis and central neurological lesions, temporomandibular joint luxation and dysplasia, osteoarthritis, retrobulbar abscess, tetanus, and severe ear disease. Treatment of locked jaw is directed towards the primary cause. It is important to treat the tonic spasm in order to minimize periarticular fibrosis. Surgical intervention is recommended for temporomandibular joint ankylosis. Masticatory muscle myositis treatment is initiated by gradually opening the mouth, with medical treatment based on immunosuppressive therapy. Fracture and masticatory muscle myositis are associated with a relatively good prognosis in regard to short-term outcome as compared to animals with central neurologic lesions or osteosarcoma which have a poor prognosis.     

Acute blindness associated with intracranial tumors in dogs and cats: eight cases (1984-1989)

Rostral and middle cranial fossa tumors affecting the optic chiasm and resulting in acute visual deficits were diagnosed in 7 dogs and 1 cat. Blindness and dilated nonresponsive pupils were the primary signs in all animals. Other concurrent neurologic deficits were either absent or were equivocal. Behavioral changes, including signs of depression and lethargy, were noticed in 1 dog and the cat subsequent to the onset of blindness. Retinal function was assessed as normal by electroretinography in all animals. The histologic necropsy diagnosis was pituitary carcinoma in 1 dog and the cat and paranasal sinus carcinoma with intracranial extension in 1 dog. A cytologic diagnosis of polycentric lymphosarcoma affecting the optic chiasm was diagnosed in 1 dog. In the remaining 4 dogs, results of computed tomographic imaging or endocrine function testing suggested pituitary gland neoplasia. Four dogs were treated with cobalt-60 radiation or chemotherapy. There was partial return of visual function in only 1 of the dogs treated with radiation.