Causes of thrombocytopenia in dogs in the United Kingdom: A retrospective study of 762 cases.

BACKGROUND: Thrombocytopenia is a common laboratory abnormality in dogs, and numerous diseases have been associated with its development. Estimates for the sensitivity and specificity of the degree of reduction of platelet concentration for the diagnosis of primary immune-mediated thrombocytopenia (pITP) have not been reported. OBJECTIVES: To report the prevalence of different causes of thrombocytopenia in dogs in the United Kingdom and to investigate the utility of platelet concentration to differentiate causes of thrombocytopenia. METHODS: Medical records of 762 dogs with thrombocytopenia presented to seven referral hospitals from January 2017 to December 2018 were retrospectively reviewed. Cases were assigned into the following categories: pITP, infectious diseases, neoplasia, inflammatory/other immune-mediated disorders and miscellaneous causes. The prevalence of the different categories was estimated, and platelet concentrations were compared. Receiver-operating characteristic (ROC) curves were used to investigate the utility of platelet concentration to differentiate between causes of thrombocytopenia. RESULTS: The most common disease category associated with thrombocytopenia was neoplasia (27.3%), followed by miscellaneous causes (26.9%), pITP (18.8%), inflammatory/immune-mediated disorders (14.4%) and infectious diseases (12.6%). Dogs with pITP had significantly lower platelet concentrations (median 8 × 109 /L, range: 0-70 × 109 /L) than dogs in the other four categories. Platelet concentration was useful for distinguishing pITP from other causes of thrombocytopenia (area under ROC curve = 0.89, 95% confidence interval 0.87, 0.92), with a platelet concentration ≤12 × 109 /L being 60% sensitive and 90% specific. CONCLUSIONS: Severe thrombocytopenia was highly specific for a diagnosis of pITP, which was more prevalent in this UK population of thrombocytopenic dogs compared with previous epidemiological studies. Conversely, the proportion of dogs with infectious diseases was lower than in previous reports from other locations.

Effect of pituitary-dependent hypercortisolism on the survival of dogs treated with radiotherapy for pituitary macroadenomas.

BACKGROUND: Radiotherapy (RT) is an effective treatment for dogs presented with neurologic signs caused by pituitary tumors. However, its impact on the outcome of concurrent pituitary-dependent hypercortisolism (PDH) is controversial. OBJECTIVES: Determine whether dogs with PDH have longer survival after pituitary RT compared with dogs with nonhormonally active pituitary masses and to evaluate whether clinical, imaging, and RT variables affect survival. ANIMALS: Ninety-four dogs divided into 2 groups: PDH and non-PDH, based on the presence of hypercortisolism. Forty-seven dogs were allocated to the PDH group and 47 to the non-PDH group. METHODS: Retrospective cohort study in which clinical records of dogs undergoing RT for pituitary macroadenomas between 2008 and 2018 at 5 referral centers were retrospectively evaluated. RESULTS: Survival was not statistically different between PDH and non-PDH groups (median survival time [MST], 590 days; 95% confidence interval [CI], 0-830 days and 738 days; 95% CI, 373-1103 days, respectively; P = .4). A definitive RT protocol was statistically associated with longer survival compared with a palliative protocol (MST 605 vs 262 days, P = .05). The only factor statistically associated with survival from multivariate Cox proportional hazard analysis was total radiation dose (Gy) delivered (P < .01). CONCLUSIONS AND CLINICAL IMPORTANCE: No statistical difference in survival was identified between the PDH and non-PDH groups, and longer survival was associated with higher Gy delivered.

Use of tranexamic acid in dogs with primary immune thrombocytopenia: A feasibility study.

Objective: The aim of this feasibility study is to evaluate the use of tranexamic acid and its safe use alongside standard therapy in dogs with primary immune thrombocytopenia (ITP). Design: This is a cohort feasibility study involving 10 dogs diagnosed with primary ITP that received standard therapy for ITP including corticosteroids, a single dose of vincristine, and omeprazole. Dogs were randomly divided into either the control group (n = 6) or the group receiving tranexamic acid (TXA group, n = 4). Key findings: The mean time from the start of treatment until remission was 5 days in the TXA group and 6 days in the control group (P = 0.69). Two dogs, one in each group, did not achieve remission. Clinical bleeding scores were not significantly different between both groups (p = 0.43), and the median blood volume administered was 37.5 ml/kg for the TXA group and 9.72 ml/kg for the control group (p = 0.084). Three out of the four dogs receiving TXA of 20 mg/kg IV started vomiting within 15 min of administration and were given a reduced dose of 15 or 10 mg/kg IV. Conclusion: Tranexamic acid did not confer a clinical benefit in this small cohort study and was associated with a high incidence of vomiting. This study provides useful information for the design of future trials in dogs with ITP receiving tranexamic acid including outcome measures and safety.

The use of high-dose immunoglobulin M-enriched human immunoglobulin in dogs with immune-mediated hemolytic anemia.

BACKGROUND: The IV use of human immunoglobulin (hIVIG) in dogs with primary immune-mediated hemolytic anemia (IMHA) has been described previously, but herein we describe the use of high-dose IgM-enriched hIVIG (Pentaglobin). HYPOTHESIS/OBJECTIVES: Dogs treated with high-dose Pentaglobin will experience shorter time to remission and hospital discharge and have decreased transfusion requirements compared to dogs receiving standard treatment alone. ANIMALS: Fourteen client-owned dogs diagnosed with primary IMHA at specialist referral hospitals in the United Kingdom. METHODS: All prospectively enrolled dogs received prednisolone, dexamethasone or both along with clopidogrel. Patients were randomized to receive Pentaglobin at 1 g/kg on up to 2 occasions, or to serve as controls. No additional immunosuppressive drugs were allowed within the first 7 days of treatment. Remission was defined as stable PCV for 24 hours followed by an increase in PCV. RESULTS: Ten of 11 dogs from the treatment group and 2 of 3 dogs from the control group achieved remission and survived until hospital discharge. Survival and time to remission were not significantly different between groups. The volume of packed red blood cells transfused, normalized for body weight, was not significantly different between groups. Potential adverse reactions to Pentaglobin occurred in 2 dogs, but their clinical signs may have been related to the underlying disease. CONCLUSIONS AND CLINICAL IMPORTANCE: Treatment with high-dose Pentaglobin was well tolerated by dogs with primary IMHA but no significant advantage was found in this small study. Additional studies examining larger groups and subpopulations of dogs with primary IMHA associated with a poorer prognosis are warranted.

Diagnostic performance of predicted ionized calcium in dogs with total hypercalcemia and total hypocalcemia.

BACKGROUND: Abnormal total calcium (tCa) values do not necessarily imply dysregulated ionized calcium. OBJECTIVES: We aimed to evaluate the diagnostic performance of predicted ionized calcium (piCa) regarding true calcium status in dogs with abnormal tCa. METHODS: This was a cross-sectional multicenter study. piCa and its prediction interval (PI) were calculated in 114 dogs, from three different hospitals, with either increased (62) or decreased tCa (52), All dogs also had ionized calcium and a biochemical profile available. The sensitivity, specificity, predictive values, and diagnostic discordance of piCa to confirm ionized hypercalcemia (iHyperCa) and ionized hypocalcemia (iHypoCa) were calculated using logistic regression analysis. RESULTS: iHyperCa was found in 28% and 66% of hyperphosphatemic and non-hyperphosphatemic dogs with tCa above the reference interval upper limit, respectively. The piCa correctly classified dogs with iHyperCa in 72.2% of those with hyperphosphatemia and 93.2% of those without hyperphosphatemia. Comparatively, elevating the tCa threshold to 12 mg/dL properly classified dogs 50% and 75% of the time in hyperphosphatemic and non-hyperphosphatemic dogs, respectively. iHypoCa was found in only 31/52 (60%) dogs with decreased tCa. The piCa correctly classified 55.2 to 100% of dogs with iHypoCa depending on the hospital. The PI demonstrated high sensitivity for iHyperCa (100%) and high specificity for both iHyperCa (100%) and iHypoCa (100%). CONCLUSIONS: Evaluating tCa alone does not reliably determine ionized calcium status. Even with hyperphosphatemia, piCa and its PI represent a reliable alternative to interpret abnormal tCa values when ionized calcium measurements are not available. However, if the tCa reference interval is notably different from 7.6 to 11.4 mg/dL, piCa values might be under/overestimated.

The multivariate predictive model to estimate ionized calcium concentration from serum biochemical results in dogs: External validation.

BACKGROUND: Predicted ionized calcium (piCa) can be calculated from routine biochemistry variables using a recently developed predictive model in dogs. However, it has not been evaluated with variables measured from multiple laboratories. OBJECTIVES: We aimed to (a) externally validate piCa in dogs where biochemistry results were obtained from different analyzers, and (b) compare the diagnostic performances of piCa and total calcium (tCa). METHODS: A cross-sectional multicentric study on 138 dogs from three different hospitals was performed. The sensitivity (Sen), specificity (Spe), positive (PPV) and negative predictive values (NPV), and diagnostic discordance of piCa and tCa were calculated using logistic regression for ionized hypercalcemia and hypocalcemia. Diagnostic performance fluctuations across hospitals were also assessed. RESULTS: For ionized hypercalcemia, the Sen (81.8%), Spe (96.1%), PPV (69.2%), NPV (97.7%), and diagnostic discordance (5.1%) of piCa were not significantly different among hospitals or from those of tCa. For ionized hypocalcemia, the Sen (range: 9.7%-53.8%) and Spe (range: 95.6%-99.6%) of piCa and tCa (Sen range: 16.2%-87.8%; Spe range: 58.3%-98.1%) varied across hospitals, although to a lesser extent for piCa. The diagnostic discordances of piCa (20.3%) and tCa (25.4%) were close. The prediction interval (PI) of piCa demonstrated high Sen to screen for ionized hypercalcemia (100%) and hypocalcemia (range: 75%-93.3%), and high Spe to diagnose ionized hypercalcemia and hypocalcemia (100% for both). CONCLUSIONS: These results support the external validation of piCa in dogs. Its PI represents a notable advantage over tCa to help clinicians explore calcium-related disorders when ionized calcium cannot be readily measured.

Pregnancy-associated immune-mediated hemolytic anemia in a dog.

OBJECTIVE: To describe the clinical presentation, diagnostic investigations, and outcome of a dog with pregnancy-associated immune-mediated hemolytic anemia. CASE SUMMARY: A 6-year-old, pregnant Bichon Frise was presented due to lethargy, inappetence, and progressive regenerative anemia with spherocytosis. The dog had been recently receiving ranitidine and amoxicillin/clavulanate. An in-house saline agglutination test identified marked agglutination and a urinalysis identified hemoglobinuria. Thoracic and abdominal imaging, as well as infectious diseases testing, was unremarkable. The bitch started whelping shortly following hospitalization, and the anemia progressively resolved without any other intervention. Ranitidine and amoxicillin/clavulanate were re-introduced within the following 2 months but the anemia did not reoccur. In light of these findings, a diagnosis of pregnancy-associated immune-mediated hemolytic anemia was made. NEW OR UNIQUE INFORMATION PROVIDED: Pregnancy-associated immune-mediated hemolytic anemia should be considered in female dogs that develop severe hemolytic anemia during pregnancy and may resolve spontaneously following parturition.

Comparative assessment of the effectiveness of three disinfection protocols for reducing bacterial contamination of stethoscopes.

In a crossover study, 30 stethoscopes were assessed and disinfected using 3 protocols: isopropyl alcohol, a quaternary ammonia or biguanide disinfectant, and ultraviolet germicidal irradiation (UVGI). All protocols effectively reduced bacterial loads, but UVGI was less effective at higher contamination levels (P = .0004). The effectiveness of each intervention was short in duration.

Concurrent somatotroph and plurihormonal pituitary adenomas in a cat.

An 8-year-old, male neutered, domestic longhair cat was referred for investigation of insulin-resistant diabetes mellitus. Routine haematology, serum biochemistry, urinalysis (including culture), total T4 and urine creatinine:cortisol ratio were unremarkable, but markedly increased insulin-like growth factor-1 concentration was identified and a pituitary mass was subsequently documented. The cat was treated conservatively with the dopamine agonist L-deprenyl and was re-presented 16 months later for worsening polyuria, polydipsia, polyphagia, marked lumbar muscle atrophy, development of a pendulous abdomen and marked thinning of the abdominal skin. Hyperadrenocorticism was diagnosed based on abdominal ultrasonography, dexamethasone suppression testing and endogenous adrenocorticotropic hormone (ACTH). The cat was treated with trilostane (30 mg q24h PO) and showed some clinical improvement, but developed an opportunistic fungal infection and skin fragility syndrome 4.5 months after commencing treatment, and was euthanased. A double-pituitary adenoma comprising a discrete somatotroph adenoma and a separate plurihormonal adenoma (positive immunoreactivity for ACTH, melanocyte-stimulating hormone and follicle-stimulating hormone) was identified on post-mortem examination. These two pituitary adenomas were suspected to have arisen as independent neoplastic entities with the plurihormonal tumour either being clinically silent at the initial presentation or having developed over the subsequent 16 months.

Clinical resolution of a nasal granuloma caused by Trichosporon loubieri.

The current report describes the diagnosis of a nasopharyngeal granuloma due to a fungal infection by Trichosporon loubieri. This is the first report of successful treatment of nasal granuloma formation caused by Trichosporon species infection in a cat.

Intra-abdominal actinomycetoma in a cat.

A 5-year-old, female Ragdoll cat was diagnosed with an intra-abdominal mycetoma involving the ileocaecal region. Diagnosis was obtained via histopathological examination following surgical resection of the mass and an ileocolic anastomosis. The initial surgery was complicated by lymphangiectasia, chylous abdominal effusion and mild bacterial leakage from the anastomosis site. A second, exploratory laparotomy was performed to augment the anastomosis with serosal patching and omentalisation and to investigate a cystic structure observed on follow-up abdominal ultrasound. Initial amoxycillin clavulanate (Clavulox; Pfizer Animal Health) therapy was ineffective, but clindamycin (Antirobe; Pfizer Animal Health) proved successful in resolving the infection. Abdominal actinomycetoma in the cat may be an under-diagnosed condition due to its close resemblance to neoplastic disease. Standard diagnostic and therapeutic regimens are commonly ineffective in Actinomyces species infections. Surgical resection along with adjunctive, long-term, selective antimicrobial therapy is effective and prognosis is good for localised lesions.