Measurement of feline-specific pancreatic lipase aids in the diagnosis of pancreatitis in cats.

OBJECTIVE: To establish a reference interval for a feline-specific pancreatic lipase assay (Spec fPL test; Idexx Laboratories Inc) in healthy cats and determine the sensitivity and specificity of the Spec fPL test in a large group of ill cats with and without pancreatitis. ANIMALS: 41 healthy cats, 141 cats with clinical signs consistent with pancreatitis, and 786 stored sera with known feline pancreatic lipase immunoreactivity (fPLI) concentrations. METHODS: This was a prospective, cross-sectional, nonrandomized study. Based on a detailed review of the medical history and results of physical examination, CBC, serum biochemical profile, urinalysis, abdominal ultrasonography, and clinical outcome, each cat was categorized by 2 board-certified internists masked to the fPLI test results into 1 of 6 categories from definitely pancreatitis to definitely not pancreatitis. RESULTS: The reference interval for the Spec fPL test, determined from the central 95th percentile of results from healthy cats, was fPLI of 0.7 to 3.5 µg/L. An fPLI concentration of ≥ 5.4 µg/L was determined to be consistent with pancreatitis. With an fPLI of 5.4 µg/L as the diagnostic cutoff, the sensitivity of the Spec fPL test for feline pancreatitis (definitely pancreatitis and probably pancreatitis) was 79.4%, the specificity for cats characterized as probably not pancreatitis and definitely not pancreatitis was 79.7%, and positive and negative predictive values were 69% and 87%, respectively. CLINICAL RELEVANCE: These findings support the use of the Spec fPL test as a valuable diagnostic test for feline pancreatitis.

Prospective Evaluation of Low-Fat Diet Monotherapy in Dogs with Presumptive Protein-Losing Enteropathy.

For dogs with protein-losing enteropathy (PLE) and evidence of lymphangiectasia, the efficacy of low-fat diet as monotherapy or combined with prednisone remains poorly characterized. In this prospective, observational cohort study of 14 dogs with presumptive PLE and ultrasonographic evidence of lymphangiectasia, subjects were placed on various low-fat diets as monotherapy and prednisone was added if response was deemed inadequate. Dogs were assessed and scored at four recheck examinations across a 6 mo study period, including a final recheck ultrasound. Clinical and clinicopathologic variables were collected and dogs were divided into three outcome groups: clinical remission on dietary monotherapy (LOF); clinical remission on dietary therapy plus immunosuppressive prednisone (LOP); and treatment failure (TXF). Eleven of 14 dogs were in clinical remission at the study end date (6 mo after enrollment): 6 LOF dogs and 5 LOP dogs. LOF dogs achieved a significant reduction in Canine Chronic Enteropathy Clinical Activity Index score and a significant increase in serum albumin within 2 wk of beginning dietary monotherapy. Four of 11 dogs in remission also had ultrasonographic evidence of resolution of linear striations. Low-fat diet appears to be an effective monotherapy in some dogs with presumptive PLE and ultrasonographic evidence of lymphangiectasia.

Diagnosis of pneumocystis pneumonia in a 2-year-old King Charles Cavalier Spaniel using the polymerase chain reaction.

A 2-year-old, female spayed, King Charles Cavalier Spaniel was presented for evaluation of dyspnea, inappetence, and lethargy. Thoracic radiographs revealed a moderate diffuse interstitial lung pattern affecting the perihilar and caudodorsal lung fields, and an echocardiogram revealed severe pulmonary hypertension. A bronchoalveolar lavage (BAL) was performed, and cytology revealed mixed inflammation with cysts and trophozoites consistent with Pneumocystis. Pneumocystis infection was later confirmed with PCR. To the author's knowledge, this report represents the first case of canine pneumocystis pneumonia diagnosed antemortem with PCR from a BAL sample. Pneumocystis represents an important, but uncommon cause of afebrile pneumonia in immunosuppressed dogs.

Prospective diagnostic accuracy evaluation and clinical utilization of a modified assay for platelet-associated immunoglobulin in thrombocytopenic and nonthrombocytopenic dogs.

BACKGROUND: No diagnostic tests reliably distinguish primary immune-mediated thrombocytopenia (pIMT) from other causes of thrombocytopenia. OBJECTIVES: The purpose of the study was to evaluate diagnostic sensitivity and specificity using modified direct and indirect platelet-associated immunoglobulin (PAIg) assays and reticulated platelets (RP) by flow cytometry for the classification of thrombocytopenic dogs and differentiating pIMT. METHODS: Platelets were isolated from plasma samples of thrombocytopenic dogs and nonthrombocytopenic healthy and ill dogs. For direct PAIg, they were analyzed by flow cytometry after incubation with anti-human amylase fluorescein isothiocyanate (FITC, negative control), anti-canine IgG-FITC, anti-canine IgM-FITC, and anti-human CD61-conjugated fluorochrome (AF647). For indirect PAIg, platelets from normothrombocytic dogs were incubated with thrombocytopenic dog plasma and analyzed similar to direct PAIg. RP percentages were determined based on forward light scatter vs thiazole orange fluorescence. RESULTS: Seventy-five thrombocytopenic dogs, 16 nonthrombocytopenic ill dogs, and 24 healthy dogs were evaluated. Diagnostic sensitivity and specificity utilizing direct IgG was 29.4% and 75.9%, respectively; when combining direct/indirect assays (IgG/IgM), it was 76.5% and 65.5%, respectively, for distinguishing pIMT. For RP, no significant difference between pIMT and sIMT was noted. RP > 8% with positive PAIg had a sensitivity of 94% and specificity of 27.6% for distinguishing pIMT. There was a significant difference in platelet concentration and CD61% staining between control and pIMT. CONCLUSIONS: The combined modified assays resulted in fair diagnostic sensitivity and specificity for the diagnosis of pIMT. The modification of the immunoglobulin assays improved diagnostic accuracy; however, a single panel to accurately classify thrombocytopenia remains elusive.

A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals.

Routine biochemical tests generally include serum enzymes, proteins, and other markers useful for identifying hepatobiliary disease in dogs and cats. Obtaining results outside the reference intervals can occur with direct hepatocellular injury, enzyme induction by hepatocytes or biliary epithelium, or decreased hepatic function. However, detection of biochemical abnormalities does not necessarily indicate clinically significant disease. For a comprehensive approach to detection and treatment of hepatobiliary disease, the laboratory results must be correlated with the history and physical examination findings, diagnostic imaging results, and other assays.

Distal renal tubular acidosis associated with concurrent leptospirosis in a dog.

A 9 yr old spayed female boxer was presented for evaluation of vomiting, lethargy, anorexia, and weight loss. Initial laboratory evaluation revealed a hyperchloremic normal anion gap metabolic acidosis with alkaline urine that was consistent with a diagnosis of distal renal tubular acidosis (RTA). Targeted therapy was initiated with Na bicarbonate (HCO3) and potassium (K) gluconate. Leptospirosis was subsequently diagnosed with paired microagglutination testing (MAT), and doxycycline was added to the other treatments. Clinical signs resolved, and 6 mo after diagnosis, although the dog remained on alkali therapy (i.e., NaHCO3 and K gluconate) and a mild metabolic acidosis persisted, the dog remained otherwise healthy with a good quality of life. To the authors' knowledge, this is the first report to describe the concomitant association of those two disorders. Leptospirosis should be considered for any case of RTA in dogs.

A laboratory diagnostic approach to hepatobiliary disease in small animals.

Routine biochemical tests generally include serum enzymes, proteins, and other markers useful for identifying hepatobiliary disease in dogs and cats. Obtaining results outside the reference intervals can occur with direct hepatocellular injury, enzyme induction by hepatocytes or biliary epithelium, or decreased hepatic function. However, detection of biochemical abnormalities does not necessarily indicate clinically significant disease. For a comprehensive approach to detection and treatment of hepatobiliary disease, the laboratory results must be correlated with the history and physical examination findings, diagnostic imaging results, and other assays.

Imaging diagnosis-MRI characteristics of a fourth ventricular cholesterol granuloma in a dog.

A 2-year-old male American Bulldog experienced paroxysmal staggering, altered consciousness, and hyperesthesia. Magnetic resonance (MR) imaging enabled recognition of a fourth ventricular mass causing compression of the cerebellum and brainstem and obstructive hydrocephalus. The mass was uniformly T2-hyperintense and predominantly T1-hypointense. A fluid line was evident on the fluid-attenuated inversion recovery images. A thin rim of contrast enhancement was noted. Histopathologic diagnosis was a cholesterol granuloma. We were unable to identify any other reports of a cholesterol granuloma residing in the fourth ventricle of a dog. This case report documents the clinical, diagnostic imaging, and histopathologic findings of a canine intracranial cholesterol granuloma. © 2012 Veterinary Radiology & Ultrasound.

Surgical management of diffuse polypoid cystitis using submucosal resection in a dog.

A 6-year-old, spayed female Labrador retriever was presented with clinical signs of stranguria, pollakiuria, and hematuria of 12 weeks' duration. A bacterial urinary tract infection, diffuse polypoid cystitis, and emphysematous cystitis were diagnosed. Antibiotic therapy combined with extensive resection of the mucosa and submucosa associated with polypoid lesions resulted in complete resolution of clinical signs and resolution of the remaining polypoid lesions. Polypoid cystitis is an uncommon but clinically relevant and reversible condition of the urinary bladder. Resection of mucosa and submucosa of the urinary bladder in dogs with polypoid cystitis may be a useful surgical treatment and can be considered as an alternative to partial cystectomy or mucosal resection.

Comparison of the effects of daily and intermittent-dose calcitriol on serum parathyroid hormone and ionized calcium concentrations in normal cats and cats with chronic renal failure.

BACKGROUND: Chronic renal failure is complicated by secondary hyperparathyroidism, which traditionally has been controlled by dietary restriction of phosphorus and administration of phosphorus binders. Early treatment of patients with chronic renal failure with calcitriol may be indicated because once established, parathyroid gland hyperplasia does not readily resolve with therapy. HYPOTHESIS: Daily and intermittent dosing of calcitriol will decrease plasma parathyroid hormone concentration in normal cats and cats with chronic renal failure without causing ionized hypercalcemia. ANIMALS: Ten normal cats; 10 cats with chronic renal failure. METHODS: Phase 1 was daily calcitriol administration (2.5 ng/kg PO q24h) for 14 days. Phase 2 was intermittent calcitriol administration (8.75 ng/kg PO q84h) for 14 days. A 7-day washout period separated phases 1 and 2. Before each phase, calcitriol, parathyroid hormone, and ionized calcium concentrations were measured. On days 1, 2, and 3 of both phases, serum ionized calcium concentrations were measured. On the last day of both phases, calcitriol, parathyroid hormone, and ionized calcium concentrations were measured 0, 2, 4, and 6 hours after calcitriol administration. RESULTS: Overall, serum parathyroid hormone concentrations were significantly higher in cats with chronic renal failure than in normal cats (P = .022), but serum parathyroid hormone concentrations for both normal cats and cats with chronic renal failure were not significantly different before and after 14 days of treatment with calcitriol, regardless of whether calcitriol was administered daily or intermittently. Adverse effects of calcitriol administration (specifically ionized hypercalcemia) were not seen in either feline group during either phase of the study over the 3-day evaluation after calcitriol administration was initiated. CONCLUSIONS AND CLINICAL IMPORTANCE: At the dosages used, calcitriol treatment did not result in significant differences in serum parathyroid hormone concentrations before and after treatment in both normal cats and cats with chronic renal failure. With these dosages, adverse affects of calcitriol administration were not seen. Potential reasons for lack of apparent effect include small sample size, insufficient duration of study, insufficient dosage of calcitriol, problems with formulation or administration of calcitriol, and variable gastrointestinal absorption of calcitriol.

Uses and effectiveness of pamidronate disodium for treatment of dogs and cats with hypercalcemia.

Uncorrected hypercalcemia can cause clinical signs such as polyuria, polydipsia, vomiting, diarrhea, lethargy, and depression and contributes to the development of primary renal failure and soft tissue mineralization. Treatment of hypercalcemia includes diagnosis and treatment of the underlying disease process and some combination of excracellular fluid volume expansion by administration of fluids intravenously and administration of glococorticosteroids, salmon calcitonin, and furosemide. Bisphosphonates such as pamidronate disodium also may be safe and effective in the treatment of hypercalcemia. The purpose of our study was to characterize the efficacy and safety of pamidronate in the treatment of hypercalcemia attritutable to several different disease processes in the dog and cat. Seven dogs and 2 cats were administered pamidronate at a dose of 1.05-2.0 mg/kg IV for a variety of disease processes, including neoplasia (n = 4), calcipotriene toxicity (n = 3), nocardiosis (n = 1), and idiopathic hypercalcemia with chronic renal failure (n = 1). In all the animals, IV pamidronate administration rapidly decreased serum calcium concentrations without evident toxicosis. Two animals received pamidronate several times without obvious toxicosis. On the basis of the findings in our retrospective study, pamidronate may be a safe and effective drug with which to lower both serum total and ionized calcium concentrations in patients with hypercalcemia arising from a wide variety of underlying disease processes.

Recent concepts in feline lower urinary tract disease.

This article presents and discusses recent concepts in feline lower urinary tract disease.

Antibiotic-responsive histiocytic ulcerative colitis in 9 dogs.

Canine histiocytic ulcerative colitis (HUC) is characterized by colonic inflammation with predominantly periodic acid-Schiff (PAS)-positive macrophages. The inflammation results in colonic thickening, ulcerations, and distortion of normal glandular architecture. Resultant clinical signs consist of chronic large bowel diarrhea, tenesmus, and marked weight loss, and the disease frequently results in euthanasia. Conventional therapy consists of some combination of prednisone, azathioprine, sulfasalazine, and metronidazole. Nine dogs (8 Boxers and 1 English Bulldog) with histologic confirmation of HUC were treated with antibiotic therapy (either with enrofloxacin alone or in combination with metronidazole and amoxicillin). Clinical signs, physical examination findings, laboratory abnormalities, and the histologic severity of the disease were evaluated. Four of the 9 dogs had been treated previously with conventional therapy and had failed to respond favorably; then, these dogs were placed on antibiotic therapy (enrofloxacin, n = 1; enrofloxacin, metronidazole, and amoxicillin, n = 3) and had resolution of clinical signs within 3-12 days. Five dogs were treated solely with antibiotic therapy (enrofloxacin, n = 1; enrofloxacin and metronidazole, n = 1; enrofloxacin, metronidazole, and amoxicillin, n = 3), and clinical signs resolved in 2-7 days. Repeated biopsy specimens were obtained from 5 dogs after treatment, and all showed marked histologic improvement. The increase in body weight after treatment was statistically significant (P = .01). Three dogs currently are not on any treatment and have had resolution of clinical signs for up to 14 months. These observations suggest that an infectious agent responsive to antibiotics plays an integral role in the clinical manifestation of canine HUC, and they support the use of antibiotics in its treatment.

Transient proximal renal tubular acidosis and Fanconi syndrome in a dog.

A 9-year-old spayed female Labrador Retriever was evaluated for anorexia, lethargy, and vomiting of 5 days' duration. Laboratory abnormalities included azotemia, high liver enzyme activities, hyperchloremic metabolic acidosis, glucosuria, ketonuria, proteinuria, and aminoaciduria. These laboratory abnormalities were diagnostic of proximal renal tubular acidosis and Fanconi syndrome. Results of initial and convalescent serologic tests for leptospirosis were negative. The dog was treated with amoxicillin, sodium bicarbonate, and potassium citrate at discharge. Repeated evaluations revealed resolution of the acidosis, azotemia, proteinuria, glucosuria, ketonuria, and high liver enzyme activities. Alkali administration was gradually discontinued, and the dog was clinically normal 8 months after discharge. The dog's clinical condition appeared to have been transient in nature, a phenomenon that is rarely seen in human or veterinary medicine.