Clinical Features,Intestinal Histopathology,and Outcome in Protein‐Losing Enteropathy in Yorkshire Terrier Dogs

Background

A poorly understood protein‐losing enteropathy (PLE) disorder has been reported in Yorkshire Terrier dogs.

Objectives

To describe clinical features, intestinal histopathology, and outcome in Yorkshire Terrier dogs with PLE, and to identify variables predictive of outcome.

Animals

Thirty client‐owned Yorkshire Terrier dogs with PLE.

Methods

Retrospective study. Records of dogs with a diagnosis of PLE were reviewed. Intestinal histopathology was interpreted using the World Small Animal Veterinary Association gastrointestinal histopathology classification system. Discriminate analysis techniques were used to identify variables predictive of outcome.

Results

Females outnumbered males (20/30). Median age was 7 years (range 1–12). Common clinical signs were diarrhea (20/30), vomiting (11), ascites and abdominal distension (11), and respiratory difficulty (8). Histopathologic abnormalities included villous lymphatic dilatation, crypt lesions, villous stunting, and variable increases in cellularity of the lamina propria. All dogs were treated with glucocorticoids. Of 23 dogs with long‐term follow‐up, 9 had complete, and 3 had partial, resolution of signs, and 11 failed to respond to treatment. Median survival of responders was 44 months and of nonresponders was 12 months, with 4 dogs experiencing peracute death. Vomiting, monocytosis, severity of hypoalbuminemia, low blood urea nitrogen concentration, and villous blunting were predictive of survival <4 months.

Conclusions

In addition to classic GI signs, Yorkshire Terriers with PLE often show clinical signs associated with hypoalbuminemia and low oncotic pressure. Lymphatic dilatation, crypt lesions, and villous stunting are consistent histopathologic findings. Clinical outcomes are variable, but many dogs experience remission of clinical signs and prolonged survival.     

Serum Biomarkers of Clinical and Cytologic Response in Dogs with Idiopathic Immune‐Mediated Polyarthropathy

Background

Immune‐mediated polyarthopathy (IMPA) is common in dogs, and is monitored by serial arthrocenteses.

Hypothesis/Objectives

Plasma C‐reactive protein (CRP), interleukin‐6 (IL‐6), and CXCL8 (interleukin‐8) would serve as noninvasive markers of joint inflammation in IMPA.

Animals

Nine client‐owned dogs with idiopathic IMPA; 6 healthy controls.

Methods

Prospective study. Plasma CRP, IL‐6, and CXCL8 were measured by ELISA at baseline, 2, and 4 weeks during treatment with prednisone at 50 mg/m²/day. Arthrocenteses, the canine brief pain inventory (CBPI), and accelerometry collars were used to assess joint inflammation, lameness, and mobility at all 3 time points.

Results

C‐reactive protein concentrations were higher in IMPA dogs (median 91.1 μg/mL, range 76.7–195.0) compared with controls (median <6.3 μg/mL, <6.3–13.7; P = .0035), and were significantly lower at week 2 (10.6 μg/mL, <6.3–48.8) and week 4 (<6.3 μg/mL, <6.3–24.4; P < .001).C‐reactive protein was correlated with median CBPI scores (r = 0.68; P = .0004), joint cellularity (r = 0.49, P = .011), and mobility by accelerometry (r = −0.42, P = .048). Plasma IL‐6 concentrations were also higher in IMPA dogs (median 45.9 pg/mL), compared with controls (median <15.7 pg/mL; P = .0008). IL‐6 was lower in IMPA dogs by week 4 (<15.7 pg/mL; P = .0099), and was modestly correlated with CBPI scores (r = 0.47, P = .023). CXCL8 did not differ significantly between IMPA and healthy dogs.

Conclusions

Plasma CRP and IL‐6 might be useful surrogate markers of synovial inflammation and disease activity in dogs with IMPA.     

Cats,Dogs and Veterinarians ‐ Do the numbers stack up?

This note is intended to focus attention on some trends which, taken together, have the potential to cause major concern to a majority of Australian veterinarians.     

Use of Contrast‐Enhanced Fluid‐Attenuated Inversion Recovery Sequence to Detect Brain Lesions in Dogs and Cats

Background

The diagnostic value of a contrast‐enhanced T2‐weighted FLAIR sequence (ceFLAIR) in brain imaging is unclear.

Hypothesis/Objectives

That the number of brain lesions detected with ceFLAIR would be no greater than the sum of lesions detected with nFLAIR and ceT1W sequence.

Animals

One hundred and twenty‐nine animals (108 dogs and 21 cats) undergoing magnetic resonance imaging (MRI) of the head between July 2010 and October 2011 were included in the study.

Methods

A transverse ceFLAIR was added to a standard brain MRI protocol. Presence and number of lesions were determined based on all available MRI sequences by 3 examiners in consensus and lesion visibility was evaluated for nFLAIR, ceFLAIR, and ceT1W sequences.

Results

Eighty‐three lesions (58 intra‐axial and 25 extra‐axial) were identified in 51 patients. Five lesions were detected with nFLAIR alone, 2 with ceT1W alone, and 1 with ceFLAIR alone. Significantly higher numbers of lesions were detected using ceFLAIR than nFLAIR (76 versus 67 lesions; P = 0.04), in particular for lesions also detected with ceT1W images (53 versus 40; P =.01). There was no significant difference between the number of lesions detected with combined nFLAIR and ceT1W sequences compared to those detected with ceFLAIR (82 versus 76; P =.25).

Conclusion and Clinical Importance

Use of ceFLAIR as a complementary sequence to nFLAIR and ceT1W sequences did not improve the detection of brain lesions and cannot be recommended as part of a routine brain MRI protocol in dogs and cats with suspected brain lesions.     

Dietary Supplements of Vitamins E and C and β-Carotene Reduce Oxidative Stress in Cats with Renal Insufficiency

Oxidative stress may contribute to the progression of chronic renal failure. In this study, cats with spontaneous renal insufficiency were fed a dry cat food supplemented with the antioxidants vitamins E and C, and β-carotene for 4 weeks. When compared with healthy cats, cats with renal insufficiency had a tendency to oxidative stress. The antioxidant supplements significantly reduced DNA damage in cats with renal insufficiency as evidenced by reduced serum 8-OHdG and comet assay parameters. Therefore, supplements of vitamins E and C and β-carotene as antioxidants may be beneficial to cats with renal disease. Partial data of this study were presented at the Experimental Biology meeting on 17–21 April, 2004. Washington DC, USA     

Bioequivalence of Orally Administered Generic,Compounded, and Innovator‐Formulated Itraconazole in Healthy Dogs

Background

Itraconazole is commonly used to treat systemic fungal infections in dogs, but problems exist with absorption and cost.

Objective

To determine oral bioequivalence of generic and compounded itraconazole compared to original innovator (brand name) itraconazole in healthy dogs.

Animals

Nine healthy, adult research Beagle dogs.

Methods

A randomized, 3‐way, 3‐period, crossover design with an 8‐day washout period. After a 12‐hour fast, each dog received 100 mg (average: 10.5 mg/kg) of either innovator itraconazole, an approved human generic capsule, or compounded itraconazole (compounded using a commercially available compounding vehicle) with a small meal. Plasma was collected at predetermined intervals for high pressure liquid chromatography analysis. Concentration data were analyzed using noncompartmental pharmacokinetics to determine area under the curve (AUC), peak concentration (C_MAX), and terminal half‐life. Bioequivalence tests compared generic and compounded itraconazole to the reference formulation.

Results

Average ratios of compounded and generic formulations to the reference formulation of itraconazole for AUC were 5.52% and 104.2%, respectively, and for C_MAX were 4.14% and 86.34%, respectively. A test of bioequivalence using 2 one‐sided tests and 90% confidence intervals did not meet bioequivalence criteria for either formulation.

Conclusion and Clinical Importance

Neither generic nor compounded itraconazole is bioequivalent to the reference formulation in dogs. However, pharmacokinetic data for generic formulation were similar enough that therapeutic concentrations could be achieved. Compounded itraconazole produced such low plasma concentrations, it is unlikely to be effective; therefore, compounded itraconazole should not be used in dogs.     

Flow Cytometric Characterization and Clinical Outcome of CD4+ T‐Cell Lymphoma in Dogs: 67 Cases

Background

Canine T‐cell lymphoma (TCL) is conventionally considered an aggressive disease, but some forms are histologically and clinically indolent. CD4 TCL is reported to be the most common subtype of TCL. We assessed flow cytometric characteristics, histologic features when available, and clinical outcomes of CD4+ TCL to determine if flow cytometry can be used to subclassify this group of lymphomas.

Objective

To test the hypothesis that canine CD4+ T‐cell lymphoma (TCL) is a homogeneous group of lymphomas with an aggressive clinical course.

Animals

Sixty‐seven dogs diagnosed with CD4+ TCL by flow cytometry and treated at 1 of 3 oncology referral clinics.

Methods

Retrospective multivariable analysis of outcome in canine CD4+ TCL including patient characteristics, treatment, and flow cytometric features.

Results

The majority of CD4+ TCL were CD45+, expressed low class II MHC, and exhibited an aggressive clinical course independent of treatment regimen (median survival, 159 days). Histologically, CD4+ TCL were classified as lymphoblastic or peripheral T cell. Size of the neoplastic lymphocytes had a modest effect on both PFI and survival in this group. A small number of CD4+ TCL were CD45− and class II MHC high, and exhibited an apparently more indolent clinical course (median survival not yet reached).

Conclusions and Clinical Importance

Although the majority of CD4+ TCL in dogs had uniform clinical and flow cytometric features and an aggressive clinical course, a subset had a unique immunophenotype that predicts significantly longer survival. This finding strengthens the utility of flow cytometry to aid in the stratification of canine lymphoma.     

Regional and Temporal Variations of Leptospira Seropositivity in Dogs in the United States, 2000–2010

Background

Previous studies have reported a seasonal increased risk for leptospirosis, but there is no consistent seasonality reported across regions in the United States.

Objectives

To evaluate and compare seasonal patterns in seropositivity for leptospirosis in dogs for 4 US regions (northeast [NE], midwest [MW], south‐central [SC], and California‐southern west coast [CS]).

Animals

Forty four thousand nine hundred and sixteen canine serum samples submitted to a commercial laboratory for microscopic agglutination tests (MAT) from 2000 through 2010.

Methods

In this retrospective study, positive cases were defined as MAT titers ≥1 : 3,200 for at least one of 7 tested serovars. Four geographic regions were defined, and MAT results were included in regional analyses based on hospital zipcode. A seasonal‐trend decomposition method for times series was utilized for the analysis. Monthly variation in the seropositive rate was evaluated using a seasonal cycle subseries plot and logistic regression.

Results

Two thousand and twelve of 44,916 (4.48%) samples were seropositive. Compared to seropositive rates for February, significantly higher monthly rates occurred during the 2nd half of the year in the MW (OR 3.92–6.35) and NE (OR 2.03–4.80) regions, and only in January (OR 2.34) and December (OR 1.74) in the SC region. Monthly seropositive rates indicative of seasonality were observed earlier in the calendar year for both CS and SC regions.

Conclusions and Clinical Importance

Seasonal patterns for seropositivity to leptospires differed by geographic region. Although risk of infection in dogs can occur year round, knowledge of seasonal trends can assist veterinarians in formulating differential diagnoses and evaluation of exposure risk.     

Immunochemical Localization of Megalin,Retinol-binding protein and Tamm–Horsfall Glycoprotein in the Kidneys of Dogs

Megalin, retinol-binding protein (RBP) and Tamm–Horsfall glycoprotein (THP) are involved in the renal metabolism of vitamin A in canine species. The presence of megalin, RBP and THP in the kidneys of dogs was investigated using immunohistochemical methods. Megalin was highly expressed in the apical membrane of the proximal convoluted and straight tubule cells. Immunoreactive RBP was detected below the apical plasma membrane, as well as in basolateral granules of the proximal convoluted tubule cells. THP immunoreactivity was seen in the epithelial cells lining the thick ascending limb of the loop of Henle. Furthermore, THP was displayed in a scattered pattern within the distal convoluted tubules. The co-localization of megalin and RBP coincides with biochemical studies that have shown megalin to be responsible for renal RBP absorption in the proximal convoluted tubules after filtration through the renal glomerulus. The presence of THP, the carrier for vitamin A in canine urine, showed that vitamin A excretion in the urine of dogs is not merely a filtration process but also seems to be a pathway located in the distal part of the nephron.