Late Toxicity and Long-Term Local Control in Patients With Ultra-Central Lung Tumours Treated by Intensity-Modulated Radiotherapy-Based Stereotactic Ablative Body Radiotherapy With Homogenous Dose Prescription.

AIMS: To report late toxicity and long-term outcomes of intensity-modulated radiotherapy (IMRT)-based stereotactic ablative body radiotherapy (SABR) in patients with ultra-central lung tumours. MATERIALS AND METHODS: This is a single-institution retrospective analysis of patients treated with SABR for ultra-central tumours between May 2008 and April 2016. Ultra-central location was defined as tumour (GTV) abutting or involving trachea, main or lobar bronchi. Respiratory motion management and static-field dynamic-IMRT were used, with dose prescribed homogeneously (maximum <120%). Descriptive analysis, Kaplan-Meier method, log-rank test and Cox regression were used to assess outcomes. RESULTS: Sixty-five per cent of patients had inoperable primary non-small cell lung cancer and 35% had lung oligometastases. The median age was 72 (range 34-85) years. The median gross tumour volume and planning target volume (PTV) were 19.6 (range 1.7-203.3) cm3 and 57.4 (range 7.7-426.6) cm3, respectively. The most commonly used dose fractionation was 60 Gy in eight fractions (n = 51, 87.8%). Median BED10 for D98%PTV and D2%PTV were 102.6 Gy and 115.06 Gy, respectively. With a median follow-up of 26.5 (range 3.2-100.5) months, fatal haemoptysis occurred in five patients (8.7%), of which two were directly attributable to SABR. A statistically significant difference was identified between median BED3 for 4 cm3 of airway, for patients who developed haemoptysis versus those who did not (147.4 versus 47.2 Gy, P = 0.005). At the last known follow-up, 50 patients (87.7%) were without local recurrence. Freedom from local progression at 2 and 4 years was 92 and 79.8%, respectively. The median overall survival was 34.3 (95% confidence interval 6.1-61.6) months. Overall survival at 2 and 4 years was 55.1 and 41.2%, respectively. CONCLUSION: In patients with high-risk ultra-central lung tumours, IMRT-based SABR with homogenous dose prescription achieves high local control, similar to that reported for peripheral tumours. Although fatal haemoptysis occurred in 8.7% of patients, a direct causality with SABR was evident in only 3%. Larger studies are warranted to ascertain factors associated with outcomes, especially toxicity, and identify patients who would probably benefit from this treatment.

Treatment of immune-mediated hemolytic anemia with individually adjusted heparin dosing in dogs.

BACKGROUND: A major cause of death in dogs with immune-mediated hemolytic anemia (IMHA) is thromboembolism. Previous studies suggest unfractionated heparin (UH) is not effective in preventing thromboembolism in IMHA; however, subtherapeutic dosing could explain the seeming lack of efficacy. HYPOTHESIS: Providing therapeutic plasma concentration of UH by individually adjusting doses based on antifactor Xa activity would improve survival in IMHA. ANIMALS: Fifteen dogs with primary IMHA. METHODS: Randomized, prospective, controlled clinical trial. Dogs received standardized therapy for IMHA and either constant dose (CD) (150 U/kg SC) (n = 7) or individually adjusted dose (IAD) (n = 8) UH, monitored via an anti-Xa chromogenic assay, adjusted according to a nomogram. UH was administered every 6 hours until day 7, and every 8 hours thereafter. UH dose was adjusted daily in IAD dogs until day 7, weekly until day 28, then tapered over 1 week. Dogs were monitored for 180 days. RESULTS: At day 180, 7 dogs in the IAD group and 1 in the CD group were alive (P= .01). Median survival time for the IAD group was >180 days, and 68 days for the CD group. Thromboembolic events occurred in 5 dogs in the CD group and 2 dogs in the IAD group. Doses of UH between 150 and 566 U/kg achieved therapeutic anti-Xa activity (0.35-0.7 U/mL). CONCLUSIONS AND CLINICAL IMPORTANCE: This study suggests that IAD UH therapy using anti-Xa monitoring reduced case fatality rate in dogs with IMHA when compared with dogs receiving fixed low dose UH therapy.

Evaluation of microsatellite instability in urine for the diagnosis of transitional cell carcinoma of the lower urinary tract in dogs.

BACKGROUND: The accumulation of frame-shift mutations in microsatellites (MS), termed microsatellite instability (MSI), is associated with certain tumors. MSI and its detection in urine samples has been used to aid in the detection of human bladder cancer. HYPOTHESIS: Evaluation of MSI in urine is a useful assay test for diagnosis of transitional cell carcinoma (TCC) in dogs and is more specific than the commercially available, veterinary bladder tumor analyte (V-BTA) test. ANIMALS: Seventy-three dogs: healthy controls (n=21), proteinuric (n=12), lower urinary tract disease excluding TCC (n=17), and TCC (n=23). METHODS: Prospective observational study. Urine samples collected from each animal were evaluated for MSI and using the V-BTA. For MSI detection, 22 MS sequences were polymerase chain reaction amplified from urine and blood, subjected to capillary electrophoresis, and the MS genotypes were compared. Aberration in ≥15% of MS was considered indicative of MSI. RESULTS: MSI was detected in 11 of 23 (48%) urine samples from dogs with TCC. MSI was also detected in 12 of 50 (24%) of the control animals, including 29, 16, and 24% of healthy, proteinuric, and lower urinary disease dogs, respectively. In this population, sensitivity and specificity of MSI analysis was 48 and 76%, respectively, compared with 83 and 64%, respectively, for the V-BTA test. CONCLUSIONS: MS analysis as performed in this study is not useful in the diagnosis of TCC.

A prospective, randomized, double-blinded, placebo-controlled study of human intravenous immunoglobulin for the acute management of presumptive primary immune-mediated thrombocytopenia in dogs.

BACKGROUND: Immune-mediated thrombocytopenia (IMT) is a common hematologic disorder in dogs. Human intravenous immunoglobulin (hIVIG) may have a beneficial effect in canine IMT. HYPOTHESIS: A single hIVIG infusion (0.5 g/kg) in dogs with presumed primary IMT (pIMT) is a safe adjunctive emergency treatment to accelerate platelet count recovery and shorten hospitalization time without increasing the cost of patient care. ANIMALS: Eighteen client-owned dogs with a presumptive diagnosis of pIMT. METHODS: Prospective, randomized, double-blinded, placebo-controlled clinical trial. RESULTS: There were no identifiable immediate or delayed adverse reactions associated with hIVIG administration over a 6-month period. The median platelet count recovery time for the hIVIG group was 3.5 days (mean + or - SD: 3.7 + or - 1.3 days; range, 2-7 days) and 7.5 days (mean + or - SD: 7.8 + or - 3.9 days; range, 3-12 days) for the placebo group. The median duration of hospitalization for hIVIG group was 4 days (mean + or - SD: 4.2 + or - 0.4 days; range, 2-8 days) and 8 days (mean + or - SD: 8.3 + or - 0.6 days; range, 4-12 days) for the placebo group. There was no significant difference between groups with respect to expense of initial patient care, whereas significant reduction in platelet count recovery time (P= .018) and duration of hospitalization (P= .027) were detected in the hIVIG group. CONCLUSIONS AND CLINICAL IMPORTANCE: Compared with corticosteroids alone, adjunctive emergency therapy of a single hIVIG infusion was safe and associated with a significant reduction in platelet count recovery time and duration of hospitalization without increasing the expense of medical care in a small group of dogs with presumed pIMT.

Abdominal wall hernia repair: a comparison of Permacol and Surgisis grafts in a rat hernia model.

BACKGROUND: This study compared two porcine-derived grafts Permacol (Tissue Science Laboratory, Covington, GA, USA) and Surgisis (Cook Surgical, Bloomington, IN, USA) in terms of strength of incorporation (SOI), incorporation of host tissue, and adhesion formation using a rat model. METHODS: A prospective randomized study using 48 Sprague-Dawley rats. A standardized 1.5 x 5 cm fascial defect was created and repaired with either Permacol or Surgisis grafts. The rats were then sacrificed at 3, 14, 28, or 60 days. The specimens were examined for SOI, neovascularization, collagen deposition, collagen organization, and adhesion formation. RESULTS: Surgisis had significantly greater SOI than Permacol at 28 (0.115 vs. 0.0754 Mpa) and 60 days (0.131 vs. 0.635 Mpa). Surgisis had significantly more collagen deposition and neovascularization than Permacol at 60 days. The area of adhesions was not significantly different between Surgisis and Permacol. CONCLUSION: Surgisis is superior to Permacol in terms of SOI and tissue ingrowth at 60 days. Furthermore, Surgisis strengthened over time whereas Permacol decreased in strength.

A retrospective study of dogs with atypical hypoadrenocorticism: a diagnostic cut-off or continuum?

OBJECTIVES: To describe the clinicopathologic findings and outcome in dogs with atypical hypoadrenocorticism (Group 1) and dogs with suspected atypical hypoadrenocorticism whose post-adrenocorticotropic hormone stimulation cortisol concentrations were greater than 55 nmol/L but below the laboratory reference interval (Group 2). METHODS: Medical records were searched to identify dogs diagnosed with hypoadrenocorticism between January 2004 and June 2014. Dogs were excluded if their Na:K ratio was less than 27 or if they had received prior therapy that could interfere with adrenocorticotropic hormone stimulation testing. RESULTS: Forty dogs were included in Group 1 and nine dogs in Group 2. In Group 1, the most common biochemical abnormalities were hypoalbuminaemia (87%) and hypocholesterolaemia (76%). Of 35 dogs in Group 1 with follow-up biochemistry results, five (14%) developed electrolyte abnormalities at 2 to 51 months post diagnosis. Of seven dogs in Group 2 with follow-up, glucocorticoid therapy was discontinued in two dogs without return of clinical signs, four dogs were subsequently diagnosed with inflammatory bowel disease and one dog continued to have clinical signs despite glucocorticoid treatment. CLINICAL SIGNIFICANCE: Dogs with gastrointestinal signs and hypoalbuminaemia and, or, hypocholesterolaemia should be evaluated for atypical hypoadrenocorticism. Follow-up electrolyte monitoring is recommended because some will develop electrolyte abnormalities. Although dogs in Group 2 had a clinical presentation compatible with atypical hypoadrenocorticism, the diagnosis appears unlikely based on review of follow-up data. Dogs with equivocal adrenocorticotropic hormone stimulation results should be evaluated for other underlying diseases such as inflammatory bowel disease. The use of endogenous adrenocorticotropic hormone measurements in these dogs warrants investigation.

Presumed primary immune-mediated neutropenia in 35 dogs: a retrospective study.

OBJECTIVES: To describe, in a cohort of dogs with presumed primary immune-mediated neutropenia, the presenting clinical characteristics, haematology results, bone marrow characteristics, therapies used (drugs and doses), clinical response to treatment, relapse and outcome at six months and one year. METHODS: Multi-institutional recruited retrospective descriptive case series with voluntary submissions. Presumed immune-mediated neutropenia was diagnosed based on a neutrophil concentration <1·5×109 cells/L on a minimum of two complete blood counts, exclusion of other causes of neutropenia based on a diagnostic bone marrow aspirate or biopsy, and exclusion of secondary immune-mediated neutropenia. Dogs meeting these diagnostic criteria between 2006 and 2013, and that had a haematocrit of ≥29% and minimum of two complete blood clounts performed after initiation of therapy, were included. RESULTS: Information on 35 dogs was included. Neutropenia was less than 0·5×109 cells/L in most cases (21 dogs), 0·5 to ·99×109 cells/L in 11, and 1.0 to 1·49×109 cells/L in three. Eight dogs had thrombocytopenia, which was severe (<49·9×109 cells/L) in three. [Correction added on 23 May 2017, after first online publication: the cell numbers were incorrect due to errors in the conversion of cell measurements to international units. The numbers have been corrected throughout the article and Table 2.] Twenty-three dogs had myeloid hyperplasia, 10 dogs had myeloid hypoplasia and two dogs had normal myelopoiesis. Neutropenia resolved in 32 of 33 dogs within two weeks of starting corticosteroid therapy and in all dogs within one month. Relapse of neutropenia occurred in 12 cases within one year. CLINICAL SIGNIFICANCE: Initial response of presumed primary immune-mediated neutropenia cases to corticosteroid therapy can be excellent. Long-term monitoring for relapse is warranted because 34% of cases relapsed during or after taper of immunosuppressive medications.

Serum Beta Hydroxybutyrate Concentrations in Cats with Chronic Kidney Disease, Hyperthyroidism, or Hepatic Lipidosis.

BACKGROUND: Ketones, including beta hydroxybutyrate (BHB), are produced in conditions of negative energy balance and decreased glucose utilization. Serum BHB concentrations in cats are poorly characterized in diseases other than diabetes mellitus. HYPOTHESIS: Serum BHB concentrations will be increased in cats with chronic kidney disease (CKD), hyperthyroidism (HT), or hepatic lipidosis (HL). ANIMALS: Twenty-eight client-owned cats with CKD, 34 cats with HT, and 15 cats with HL; 43 healthy cats. METHODS: Prospective observational study. Serum BHB concentrations were measured at admission in cats with CKD, HT, and HL, for comparison with a reference interval established using healthy cats. Results of dipstick urine ketone measurement, when available, were compared to BHB measurement. RESULTS: Beta hydroxybutyrate was above the reference interval (<0.11 mmol/L) in 6/28 cats (21%) with CKD, 7/34 cats (20%) with HT, and 11/15 cats (73%) with HL, significantly exceeding the expected 2.5% above the reference interval for healthy cats (P < .001 for all groups). Elevations were mild in CKD and HT groups (median BHB 0.1 mmol/L for both groups, 80th percentile 0.12 and 0.11 mmol/L, respectively), but more marked in HL cats (median BHB 0.2 mmol/L, 80th percentile 0.84 mmol/L). None of 11 cats with increased serum BHB concentration having urine dipstick analysis performed within 24 h of sampling for BHB were ketonuric. CONCLUSIONS AND CLINICAL IMPORTANCE: Increases in serum BHB concentrations occur in cats with CKD, HT, and HL, and might provide an useful index of catabolism.

Fasting urinary calcium-to-creatinine and oxalate-to-creatinine ratios in dogs with calcium oxalate urolithiasis and breed-matched controls.

BACKGROUND: Hypercalciuria and hyperoxaluria are risk factors for calcium oxalate (CaOx) urolithiasis, but breed-specific reports of urinary metabolites and their relationship with stone status are lacking. OBJECTIVE: To compare urinary metabolites (calcium and oxalate) and blood ionized calcium (iCa) concentrations between CaOx stone formers and breed-matched stone-free controls for the Miniature Schnauzer, Bichon Frise, and Shih Tzu breeds. ANIMALS: Forty-seven Miniature Schnauzers (23 cases and 24 controls), 27 Bichons Frise (14 cases and 13 controls), and 15 Shih Tzus (7 cases and 8 controls). METHODS: Prospective study. Fasting spot urinary calcium-to-creatinine and oxalate-to-creatinine ratios (UCa/Cr and UOx/Cr, respectively) and blood iCa concentrations were measured and compared between cases and controls within and across breeds. Regression models were used to test the effect of patient and environmental factors on these variables. RESULTS: UCa/Cr was higher in cases than controls for each of the 3 breeds. In addition to stone status, being on a therapeutic food designed to prevent CaOx stone recurrence was associated with higher UCa/Cr. UOx/Cr did not differ between cases and controls for any of the breeds. Blood iCa was higher in cases than controls in the Miniature Schnauzer and Bichon Frise breeds and had a moderate correlation with UCa/Cr. CONCLUSIONS AND CLINICAL IMPORTANCE: Hypercalciuria is associated with CaOx stone status in the Miniature Schnauzer, Bichon Frise, and Shih Tzu breeds. UOx/Cr did not correlate with stone status in these 3 breeds. These findings may influence breed-specific stone prevention recommendations.

Effects of nitrous oxide on psychological performance. A dose-response study using inhalation of concentrations up to 15%.

In this six-period randomised double-blind study, 12 healthy volunteers inhaled mixtures of nitrous oxide at concentrations of 0% (placebo); 3%, 5%, 7%, 10%, and 15% in oxygen. Each concentration was inhaled for 55 min, each period being on a separate day. The order of treatments was randomised using a Latin-Square design. The effects of nitrous oxide were assessed using a battery of performance tests which included measures of attention, psychomotor function, memory and cognition. Mood was assessed using visual analogue scales. Measures of attention and psychomotor performance showed impairment at 15% nitrous oxide, and subjective measures showed sedation at this dose. The Buschke Selective Reminding Task showed impairment to long-term recall at all doses of nitrous oxide compared to placebo, while short-term recall was impaired only at 15%. These results suggest that consolidation of memory may be particularly sensitive to disruption as a result of CNS depression.

Airway reactivity in ponies with recurrent airway obstruction (heaves).

We measured lung function and airway reactivity to histamine administered by aerosol in two groups of ponies. Principal ponies had a history of heaves, a disease characterized by recurrent airway obstruction when ponies are housed in a barn and fed hay; control ponies had no history of airway obstruction. Ponies were paired (principal and control) and measurements were made when principal ponies were at pasture and in clinical remission (period A), following barn housing when principal ponies had acute airway obstruction (period B), and after a further 1 and 2 wk at pasture (periods C and D). At periods A, C, and D dynamic compliance (Cdyn), pulmonary resistance (RL), arterial O2 tension (PaO2), and CO2 tension (PaCO2) of principals and controls did not differ. Barn housing (period B) decreased Cdyn and PaO2 and increased RL in principals but not controls. The ED65Cdyn (the dose of histamine to reduce Cdyn to 65% of base line) did not differ in principals and controls at periods A, C, and D. At period B, ED65Cdyn decreased by 2.5-log doses of histamine in principals while ED65Cdyn was not affected in controls. There was no correlation between changes in airway reactivity and changes in RL and Cdyn. We conclude that ponies in clinical remission from heaves are not hyperreactive to histamine aerosol. This model of lung disease is similar to some forms of industrial asthma in which hyperreactivity occurs only during acute airway obstruction. The lack of correlation between ED65Cdyn and the degree of airway obstruction suggests that the hyperreactivity of principal ponies to histamine aerosol cannot be explained solely by alterations in baseline airway caliber.

Epidemiology of Pseudomonas aeruginosa in an intensive care unit using selective decontamination of the digestive tract.

Selective decontamination of the digestive tract (SDD) aims to reduce the rate of nosocomial infections in critical care patients. Pseudomonas spp. are common nosocomial pathogens and in this study isolates collected from patients and the environment during an SDD trial were examined. The study enrolled 161 SDD cases and 170 controls. Pseudomonads were isolated from 27% of SDD patients and 30% of controls. SDD partially suppressed colonization in the 'gastro-respiratory' mucosae but not in the rectum. A total of 108 isolates of pseudomonads were recovered from the environment. Resistance in rectal isolates was minimal but isolates from 'gastro-respiratory' sites showed increasing aminoglycoside resistance. Eighty-six per cent of aminoglycoside-resistant isolates from both patient groups and environment were pyocine type 1x. Episodes of infection were reduced in the SDD patients (6) compared with the controls (16), aminoglycoside-resistant strains being associated with zero episodes in SDD patients but with five in the control group.

Cell-mediated immune responses to liver membrane protein in canine chronic hepatitis.

Peripheral blood mononuclear cells from dogs with chronic inflammatory liver disease and dogs with noninflammatory liver diseases were evaluated for proliferative responses to pokeweed mitogen and canine liver membrane protein. Dogs with chronic hepatitis were selected based on histopathological evidence of periportal lymphocytic infiltrates with or without neutrophilic infiltrates, fibrosis and necrosis. Incorporation of tritiated thymidine was assessed 72 hours after addition of liver membrane protein or pokeweed mitogen. Peripheral blood mononuclear cell proliferation in response to liver membrane protein was significantly higher in chronic hepatitis dogs compared to control dogs. Eight of 12 dogs with chronic hepatitis and 2 of 7 dogs with noninflammatory liver disease had proliferative responses to liver membrane protein greater than 2 standard deviations above the mean of the control group. These data support the hypothesis that immune-mediated processes are involved in canine chronic hepatitis, but did not determine whether this is a primary disorder or occurred secondary to liver destruction.

Percutaneous endoscopic gastrostomy. A retrospective study of 54 clinical cases in dogs and cats.

Results are presented of consecutive percutaneous endoscopic gastrostomies (PEGs) performed in 32 feline and 22 canine patients over a 30-month period. Indications for PEG placement were hepatic disease (33%), esophageal disease (32%), oronasal abnormalities (22%), and cranial nerve deficits (4%), with miscellaneous conditions accounting for 9%. The median duration that PEG tubes were in place was 18 days (range, 0-320 days). The suitability of this feeding technique for clinical use was assessed by evaluating mortality, procedure-related and delayed complications, and body weight changes by the end of the PEG feeding period. Fifty-two of 54 PEGs were placed and used successfully. One fatality occurred during tube insertion due to splenic laceration, and one dog died of aspiration pneumonia secondary to pharyngoesophageal dysfunction. Other than splenic laceration, procedure-related complications were benign pneumoperitoneum (1/54) and minor gastric hemorrhage resulting in melena (1/54). Delayed complications occurring 24 hours or longer after the procedure included aspiration (4/54), peristomal infection or excessive granulation tissue (3/54), and tube extraction or migration (3/54). Nineteen of 54 animals showed evidence of inadequate gastric emptying or volume intolerance when food was introduced after PEG placement. This effect was minor and easily resolved. Of the 44 animals for which follow-up body weight information was available, 19 gained weight, six remained static, and 19 lost weight during the PEG feeding period. Percutaneous gastrostomy is a relatively safe, effective procedure and should be given early consideration for medium- or long-term enteral nutritional support in appropriate canine and feline patients.

Anti-liver membrane protein antibodies in dogs with chronic hepatitis.

Serum from 21 dogs with chronic hepatitis was evaluated for anti-liver membrane protein (anti-LMP) antibodies by an enzyme-linked immunosorbent assay. Ten of the 21 dogs had anti-LMP antibody concentrations greater than 2 SD above the mean value for the 10 healthy control dogs; titers ranged from 1:40 to greater than 1:1,600. Anti-LMP-positive dogs were not restricted by breed, had higher alanine amino transferase activity and total bilirubin concentration, and more severe liver lesions when compared with anti-LMP-negative dogs. This study provided evidence of humoral autoantibodies in dogs with chronic hepatitis, but it did not determine if the autoantibodies were primary or secondary.

Therapy of immune mediated thrombocytopenia. A retrospective study of 15 dogs.

Fifteen dogs with immune mediated thrombocytopenia (IMT) were studied retrospectively. All dogs had a thrombocyte count below 50,000/microliters when response to therapy was studied. Platelet counts greater than 50,000/microliters were present in all dogs within 2-9 days of initiating medical therapy. Eight dogs experienced a single episode of thrombocytopenia and seven dogs relapsed over the following 5 to 24 months. Clinical parameters from dogs that experienced a single episode of IMT were compared with data from dogs that relapsed to determine whether any information would identify dogs that were prone to relapse. Signalment, severity of thrombocytopenia, and time to achieve a platelet count above 50,000/microliters were found not to differ (P greater than 0.05) between these two groups. Five of the seven dogs with relapsing IMT were splenectomized after 2 to 4 episodes (mean, 2.8 +/- 0.8) of thrombocytopenia over 2 to 14 months. The postoperative progress of these five dogs was followed for 6 to 17 months. Platelet counts were sustained above 200,000/microliters in 4/5 after splenectomy and it was possible to discontinue medical therapy in these dogs. In comparison, the 2 relapsing IMT cases that were not splenectomized continued to require intermittent immunosuppressive therapy. We conclude that signalment and routine pretreatment laboratory test results are not useful in distinguishing dogs with relapsing IMT from those that will experience one episode of IMT. Seemingly, splenectomy is useful in the management of dogs with relapsing IMT.

Hypomagnesemia in 188 dogs: a hospital population-based prevalence study.

Magnesium is a divalent cation involved in more than 300 metabolic processes. Magnesium acts as an intracellular regulator of most energy-demanding pathways. Clinical investigation in the human medical field has determined risk factors for hypomagnesemia and its relationship to a number of disease processes. Experimental studies have established the effects of hypomagnesemia in dogs, but little is known of its prevalence, risk factors, or clinical associations in a hospital population of dogs. To study the prevalence, risk factors, and clinical associations of hypomagnesemia in dogs, a retrospective cross-sectional study of dogs admitted to the University of Minnesota Veterinary Teaching Hospital over a 2.5-year period was undertaken. The prevalence of hypomagnesemia in the study population was 6.1% (188 of 3,102 dogs). Using both categorical and continuous variables in a univariate analysis, significant associations with hypomagnesemia were identified and used to construct a multivariate analysis of the relative risk of hypomagnesemia. Results from evaluation of 3,102 dogs indicate that the most significant predictors of hypomagnesemia were albumin (P < or = .0001; odds ratio [OR] = 0.2), potassium (P < or = .0001; OR = 0.5), total CO2 (P < or = .05; OR = 0.9), and blood urea nitrogen concentrations (P < .0001; OR = 0.9), a diagnosis of cardiovascular disease (P < .02; OR = 1.9); and being a Collie (P < .02; OR = 3.9) or German Shepherd Dog (P < .002; OR = 2.2). These results can be used to better understand and predict hypomagnesemia in dogs.

Evaluation of citrate-phosphate-dextrose-adenine as a storage medium for packed canine erythrocytes.

Packed canine red blood cells (RBCs) stored in the anticoagulant-preservative solution citrate-phosphate-dextrose-adenine (CPDA-1) were studied at 1, 10, 20, 30, and 40 days. The extracellular concentrations of potassium and sodium, erythrocyte mean corpuscular volume, and osmotic fragility increased during storage (P less than 0.05). There was a decrease in the pH, plasma concentration of glucose, and erythrocyte concentrations of 2,3-diphosphoglycerate (2,3-DPG) and adenosine-5'-triphosphate (P less than 0.05). Erythrocyte 2,3-DPG concentration decreased by 54% within the first 24 hours of storage (P less than 0.001). Posttransfusion viability (PTV) decreased from 90% on day 1 to 46% on day 40 (P less than 0.05). The PTV of the RBCs stored for 10 and 20 days complied with the Food and Drug Administration (FDA) standard. Although there are marked biochemical and hematologic changes in stored packed red blood cells (pRBCs), 20-day-old units may be expected to be of acceptable quality. The sharp decrease in 2,3-DPG concentration suggests a reduction in oxygen carrying capacity in erythrocytes stored as pRBCs. Hyperkalemia occurs during storage of pRBCs and does not appear to be associated with high intraerythrocytic potassium concentrations.

The effects of cyclosporine versus standard care in dogs with naturally occurring glomerulonephritis.

Glomerulonephritis (GN) is a leading cause of chronic renal failure in dogs. However, little is known about the efficacy of available treatment options for GN in this species. The purpose of this study was to determine the effects of cyclosporine (Cy) administration on the outcome of naturally occurring GN in dogs. Thirteen dogs from 4 institutions were included in the study. Randomization of dogs into placebo-versus Cy-treated groups was stratified according to initial morphological diagnosis and contributing institution. Seven and 6 dogs were assigned to be given placebo or Cy, respectively. The initial Cy dose of 10 mg/kg every 24 hours was adjusted to maintain 24-hour trough, whole blood Cy concentrations between 250 and 400 ng/mL. There were no statistically significant differences between placebo- and Cy-treated groups with respect to serum total protein, albumin, urea nitrogen and creatinine, and plasma protein concentrations; platelet count; urine protein-creatinine ratio; endogenous creatinine clearance; 24-hour urine protein concentrations; or 24-hour urine protein-endogenous creatinine clearance ratio. However, PCV was significantly lower in the Cy-treated group. Decreased appetite, diarrhea, vomiting, weight loss, involuntary shaking, and thrombocytopenia were noted in both treatment groups; however, clinical signs in Cy-treated dogs subjectively were more severe. One Cy-treated dog developed gingival hyperplasia.(ABSTRACT TRUNCATED AT 250 WORDS)

Intravenous histamine administration in ponies with recurrent airway obstruction (heaves).

Pulmonary function and airway reactivity to IV histamine were measured in a group of ponies with a history of recurrent airway obstruction (heaves) and their age-, weight-, and gender-matched controls. Ponies were studied during a period of clinical remission (period A), after exposure to a barn environment (period B), and twice during a 2-week recovery phase (periods C and D). At periods A, C, and D, PaO2, dynamic compliance (Cdyn), pulmonary resistance, tidal volume, respiratory frequency, and the log dose of histamine required to reduce Cdyn to 65% of base-line value (log ED65Cdyn) of principals and controls did not differ. Barn exposure (period B) decreased Cdyn, PaO2, and ED65Cdyn and increased pulmonary resistance in principals but not controls. The slope of the histamine dose-Cdyn response curves was not different between principal and control groups of ponies and was unaffected by barn exposure or return to pasture. There was a poor correlation between ED65Cdyn and indices of airway caliber. During acute airway obstruction, ponies with a history of heaves were hyperreactive to IV histamine, but during disease remission, airway response to histamine was not different from that of control ponies. Seemingly, hyperreactivity in principal ponies after exposure to a barn environment cannot be explained solely by alterations in base-line airway caliber.