Review of feline pancreatitis part two: clinical signs, diagnosis and treatment

In the past decade pancreatitis has become recognised as a significant disease in the cat. Chronic, mild pancreatitis is often associated with more commonly diagnosed diseases such as inflammatory bowel disease or cholangitis/cholangiohepatitis. Furthermore, acute pancreatitis with similar complications to those seen in dogs is now diagnosed more frequently in cats. Unfortunately, the clinical signs and clinicopathological findings in cats with pancreatitis are often non-specific and vague. The lack of specific signs often results in a diagnosis being made only when the veterinary surgeon has a strong index of suspicion for pancreatitis and vigorously pursues that diagnosis. Pancreatitis is an important disease in cats, has been implicated as a potential cause of diabetes mellitus, and when present complicates the treatment of diabetes and other intra-abdominal diseases in cats.     

A review of the pathophysiology, classification, and analysis of canine and feline cavitary effusions

Effusion is the abnormal accumulation of fluid within a body cavity that can result from a variety of disease processes. This article reviews the normal production and resorption of body cavity fluid and the pathophysiology of abnormal fluid accumulation. In addition, classification schemes, differential diagnoses, and currently available diagnostic tests for evaluation of effusions are reviewed.     

Current understanding of feline diabetes: part 1, pathogenesis

Type-1 diabetes, resulting from immune-mediated destruction of beta cells, appears to be rare in cats. Type-2 diabetes, characterised by inadequate insulin secretion and impaired insulin action, is the most common form of diabetes in cats. Other specific forms of diabetes constitute a substantial minority of cases. The most common is pancreatic destruction from pancreatic adenocarcinoma. Less frequent causes are insulin resistance from other endocrinopathies including acromegaly. Diabetes in cats is characterised by variable loss of insulin secretory capacity and insulin resistance. Glucose toxicity, islet amyloid-deposition, and pancreatitis contribute to further loss of beta cells and failure of insulin secretion. A significant number of cats undergo remission of their diabetes, usually 1-3 months after good glycaemic control is instituted. Obesity, old age, and Burmese breed are recognised risk factors for the development of diabetes in cats.     

Current understanding of feline diabetes: part 2, treatment.

When treating diabetic cats, the primary aim is to control clinical signs without causing clinical hypoglycaemia. Secondary goals are to maximise the chances of attaining diabetic remission and to minimise the risk of complications due to chronic hyperglycaemia. A treatment plan that is convenient for the owner is important for compliance. Underweight or overweight diabetic cats should be fed with the aim of normalising bodyweight. Current evidence suggests that non-obese diabetic cats can be fed ad libitum. The oral hypoglycaemic drug glipizide is well established as a treatment for about a third of diabetic cats, which have residual beta cell function. Preliminary studies on other oral agents such as vanadium salts, metformin, and troglitazone indicate a potential use in some diabetic cats. Insulin treatment remains the treatment of choice for the majority of diabetic cats. Choice of insulin, dose rates and monitoring of treatment are discussed.     

Clinical and histopathological classification of feline intraocular lymphoma

This retrospective study aimed to describe and classify cats with intraocular lymphoma, determine the proportion of cases with presumed solitary ocular lymphoma (PSOL) compared with ocular manifestations of multicentric disease and assess the clinical outcomes of these patients. One hundred seventy‐two cases identified through biopsy submissions were reviewed histologically; 163 of these cases were subtyped according to the WHO classification system. Cases were categorized as having PSOL or ocular lymphoma with suspected systemic involvement (SSI) based on submission forms and follow‐up data. The majority of cases exhibited concurrent uveitis (75%) and secondary glaucoma (58%). Diffuse large B‐cell lymphoma was the most common subtype (n = 86; 53%), followed by peripheral T‐cell lymphoma (n = 44; 27%). Other subtypes included anaplastic large T‐ (n = 8; 5%) and B‐cell (n = 4; 2.5%) lymphomas, and 15 cases (9%) were negative for all immunohistochemical markers. In sixty‐nine cases (40%), adequate clinical data and sufficient survival data were obtained to distinguish PSOL from SSI. PSOL comprised the majority of cases (64%), while 36% had SSI. When covarying for age at diagnosis, the median survival time was significantly higher (P = 0.003) for cases of PSOL (154 days) versus those with SSI (69 days); hazards ratio of 0.47 for PSOL (95% CI: 0.241‐0.937). The subtype of lymphoma did not affect survival time. Cats with PSOL represent a greater proportion of the disease population, and this subset of cats with intraocular lymphoma has a better clinical outcome.     

Histopathologic findings and classification of feline renal transplants

Seventy-seven feline transplant kidney specimens, obtained from 1 to 3,183 days (9 years) after transplantation, were reevaluated histologically and classified on the basis of the Banff '97 guidelines for human renal transplant kidneys. Overall, this classification system appeared useful in detecting rejection reactions and confirmed the finding in humans that biopsies can diagnose subclinical rejection and therefore are an important diagnostic tool for the follow up of renal transplants. However, on the basis of serum creatinine values, the severity of the acute or active and chronic lesions was not accurately reflected by this scoring system. This is thought to be due to the significant differences in histologic rejection patterns, especially in acute or active rejection, in cats when compared with humans. Tubulitis, lymphocytic glomerulitis, and vasculitis, which are the main pillars of the Banff '97 acute or active rejection scoring system, are either rare or not found in cats. The presence of significant necrotizing glomerulitis and vasculitis in feline renal transplants might imply that the rejection is complicated by acute antibody-mediated rejection. Alternatively, cyclosporine toxicity also should be considered because some of these kidneys show other signs of cyclosporine toxicity. Finally, the significance of subcapsular and interlobular phlebitis, rarely described in human rejection reactions but a distinct entity in cats, is unknown. From this study, it is clear that there are significant differences in the histology of acute or active rejection between humans and cats and that a better understanding of the histologic appearance of renal allografts will be especially beneficial for treatment and prognostic purposes.     

Prevalence of feline cataract: results of a cross-sectional study of 2000 normal animals, 50 cats with diabetes and one hundred cats following dehydrational crises

Objective In this study 2000 normal cats, 50 cats with diabetes and 100 cats with a history of dehydrational crises were examined ophthalmoscopically to determine presence of cataract. Materials and methods The cats examined were predominantly from veterinary hospital populations but also from re‐homing facilities and breeding catteries. Prevalence of cataract was determined for different age groups (year cohorts). The age at which prevalence of cataract was 50% (C₅₀) was determined indirectly from a fitted prevalence curve as previously described. C₅₀ was determined for animals of different genders and different breeds as well as for those with diabetes and histories of dehydrational episodes related to chronic renal failure, chronic vomiting or chronic diarrhea. Results The mean ± standard deviation of C₅₀ for all normal cats in the study was 12.7 ± 3.4 years. All cats over 17.5 years were affected by some degree of lens opacity. C₅₀ for cats with diabetes was 5.6 ± 1.9 years (significantly different from normal cats at P < 0.0001). For cats with a history of dehydrational crises C₅₀ was 9.9 ± 2.5 (difference from normal cats nearing statistical significance at P = 0.06). Conclusion The study yields novel findings regarding the prevalence of age‐related cataract in normal cats together with cats with diabetes and history of previous dehydrational episodes in which prevalence of cataract is increased.     

Johne's disease in Canada Part I: clinical symptoms, pathophysiology, diagnosis, and prevalence in dairy herds

Recent international developments in the area of infectious disease control and nontariff trade barriers, along with possible zoonotic concerns, have provoked a revival of interest in Johne's disease in Canada and elsewhere. The bacterium causing Johne's disease, Mycobacterium avium subspecies paratuberculosis, is distributed worldwide and causes chronic granulomatous enteritis, also known as paratuberculosis, in domestic and exotic ruminants, including cattle. The subclinical form of this disease results in progressive weight loss, reduced milk production, lower slaughter value, and premature culling, with possible impacts on fertility and udder health. Eventually, infection can lead to the clinical form that manifests as chronic diarrhea, emaciation, debilitation, and eventual death. Currently, available tests to detect infected animals produce many false-negative results and some false-positives, particularly in subclinically infected animals, thus making their interpretation and utilization challenging in control programs. The objective of this 2-part review is to critically review the literature about Johne's disease in dairy cattle for bovine practitioners in Canada. Part I covers the clinical stages, pathophysiology, diagnosis, and prevalence of infection in Canada, while Part II discusses impacts, risk factors, and control programs relevant to Canadian dairy farms. By reviewing the scientific literature about Johne's disease, control of the disease could be pursued through informed implementation of rational biosecurity efforts and the strategic use of testing and culling.     

Determination of the prevalence of feline blood types in the UK

The efficacy and diagnostic accuracy of a new desk-top feline blood typing kit was evaluated by comparing the results of the kit with traditional blood typing methods on 35 feline blood samples. The kit was then used to blood type 139 non-pedigree cats from Scotland and the north of England and 207 pedigree cats from throughout the UK. Of the non-pedigree cats, 87.1 per cent were type A, 7.9 per cent were type B and 5.0 per cent were type AB, while of the pedigree cats, 54.6 per cent were type A, 40.1 per cent were type B and 5.3 per cent were type AB. The majority (121 out of 207) of these pedigree cats were British shorthaired, of which 39.7 per cent were type A, 58.7 per cent were type B and 1.6 per cent were type AB. No cats were identified that failed to express the type A and/or type B antigens. The prevalence of type AB cats appears to be higher in this study than previously reported. The prevalence of blood types within specific pedigree breeds in the UK appears to vary from that reported elsewhere.     

Sonographic evaluation of the normal and abnormal pancreas

Pancreatic disorders in dogs and cats are recognized with increasing frequency, and abdominal ultrasonography has assumed an important role in their diagnosis. The normal pancreas is a small, inconspicuous organ of comparable echogenicity to surrounding mesentery and may be difficult to identify. Therefore, knowledge of anatomic landmarks such as portal vein and contributing vessels, duodenum, and stomach is necessary to facilitate identification and examination. Pancreatic diseases and abnormalities frequently investigated by means of ultrasonography include pancreatitis, pseudocysts, abscesses, neoplastic lesions, and nodular hyperplasia. Disorders less commonly seen include exocrine pancreatic insufficiency, pancreatolithiasis, congenital anomalies, and pancreatic edema. Unfortunately, ultrasonographic findings in various pancreatic disorders overlap, and incidental findings or age-related changes may mimic pancreatic disease. On the other hand, pancreatic disorders may not cause changes in ultrasonographic appearance. Ultrasonographic findings, therefore, have to be judged in light of signalment, history, and laboratory data. Cytology or histopathology may be needed to establish a definite diagnosis. Despite these limitations, ultrasonography is useful in diagnosing pancreatic disease, guiding aspirates and biopsies, and monitoring response to treatment.     

Expression of E-cadherin in normal, hyperplastic and neoplastic feline mammary tissue

This paper describes an immunohistochemical study of the expression of E-cadherin in four samples of normal, eight samples of hyperplastic and 19 samples of neoplastic feline mammary tissue. In the normal tissues, the luminal epithelial cells showed a strong pattern of staining for E-cadherin at the cell-cell boundaries, whereas the myoepithelium showed no immunoreactivity. In the hyperplastic tissues and the five benign neoplasms, there were disturbances in the expression of E-cadherin in the luminal epithelium, in the form of the coexistence of membranous and cytoplasmic staining, together with immunoreactivity in a small percentage of myoepithelial cells. In 11 of 14 carcinomas, there was a reduction or absence of E-cadherin expression and abnormalities in the pattern of immunostaining; these changes were more pronounced in cribriform and solid carcinomas.     

Quantitative studies of erythropoiesis in the clinically normal, phlebotomized, and feline leukemia virus-infected cat

Erythropoiesis was evaluated in 5 cats at base line with normal PCV and then in the same cats with anemia induced by phlebotomy and in 5 other cats with nonregenerative anemia from community-acquired feline leukemia virus (FeLV) infection. The hematologic evaluation included complete blood cell and reticulocyte counts, marrow morphologic features, determination of serum erythropoietin concentrations by radioimmunoassay, ferrokinetic studies, and in vitro marrow culture of early erythroid progenitors (erythroid burst-forming units; BFU-E) and late erythroid progenitors (erythroid colony-forming units; CFU-E). Phlebotomized cats developed marrow erythroid hyperplasia and an increased reticulocyte count. Ferrokinetic studies revealed an increase in plasma iron turnover from 1.4 to 3.8 mg of Fe/dl of blood/day and RBC use from 50.4% to 78.5%. The mean CFU-E number and CFU-E/BFU-E ratio increased after phlebotomy, but the increase was not significant (P greater than 0.05). Serum erythropoietin values did increase significantly. In FeLV-infected cats, a nonregenerative anemia was demonstrated by marrow erythroid hypoplasia and a low total reticulocyte count. An increased percentage of rubriblasts and prorubricytes was observed in 4 of the 5 cats. Although serum erythropoietin values were high (321 +/- 123 mU/ml vs normal 14 +/- 1 mU/ml), ferrokinetic data revealed decreased erythropoiesis. Marrow culture studies in the FeLV-infected cats also revealed low numbers of BFU-E and CFU-E, but normal numbers of granulocyte-macrophage progenitors remained. Seemingly, the FeLV infection impaired the ability of feline marrow to respond physiologically to anemia.     

Isolation and classification of feline picornavirus and herpesvirus in Denmark

Seventeen viral isolates cytopathic for kitten kidney cells were isolated from 23 cats with symptoms of the respiratory disease feline viral rhinotracheitis or feline influenza. Five of these are classified tentatively as calicivirus, a member of the Picornavirus group, and 12 have the properties of the herpesvirus. Classification is based on the cytopathic effect in cell cultures and physico-chemical characteristics.The five isolates which are classified tentatively as calicivirus produced a quick cytopathic effect without formation of intranuclear inclusion bodies. The isolates were resistant to chloroform, were not inhibited by IDU, were labile at pH 4 and were not stabilized against thermal inactivation by molar MgCl₂. The 12 isolates which seem to belong to the herpesvirus produced intranuclear inclusion bodies in cell cultures. They were sensitive to chloroform, and multiplication was inhibited by IDU. Antisera were produced by inoculating rabbits with calicivirus and cats with herpesvirus. The five isolates classified tentatively as calicivirus belong in one serotype, and the 12 isolates which seem to belong to the herpesvirus also belong in one serotype.Keyword: feline Picornavirus, feline calicivirus, feline herpesvirus, feline viral rhinotracheitis, feline influenza, isolation, classification, Denmark     

Evaluation of serum feline pancreatic lipase immunoreactivity and helical computed tomography versus conventional testing for the diagnosis of feline pancreatitis

Serum feline trypsinogen-like immunoreactivity (fTLI) concentrations and abdominal ultrasound have facilitated the noninvasive diagnosis of pancreatitis in cats, but low sensitivities (33% and 20–35%, respectively) have been reported. A radioimmunoassay has been validated to measure feline pancreatic lipase immunoreactivity (fPLI), but the assay's sensitivity and specificity have not been established. In human beings, the sensitivity of computed tomography (CT) is high (75–90%), but in a study of 10 cats, only 2 had CT changes suggestive of pancreatitis. We prospectively evaluated these diagnostic tests in cats with and without pancreatitis. In all cats, serum was obtained for fTLI and fPLI concentrations, and pancreatic ultrasound images and biopsies were acquired. Serum fPLI concentrations ( P <.0001) and ultrasound findings ( P = .0073) were significantly different between healthy cats and cats with pancreatitis. Serum fTLI concentrations ( P = .15) and CT measurements ( P = .18) were not significantly different between the groups. The sensitivity of fTLI in cats with moderate to severe pancreatitis was 80%, and the specificity in healthy cats was 75%. Feline PLI concentrations were both sensitive in cats with moderate to severe pancreatitis (100%) and specific in the healthy cats (100%). Abdominal ultrasound was both sensitive in cats with moderate to severe pancreatitis (80%) and specific in healthy cats (88%). The high sensitivities of fPLI and abdominal ultrasound suggest that these tests should play an important role in the noninvasive diagnosis of feline pancreatitis. As suggested by a previous study, pancreatic CT is not a useful diagnostic test for feline pancreatitis.     

Review on canine elbow dysplasia: pathogenesis, diagnosis, prevalence and genetic aspects

Elbow dysplasia (ED) is a progressive skeletal disease, which may comprise osteoarthrotic changes, incongruity of the joint, a fragmented medial coronoid process (FCP), osteochondrosis dissecans of the trochlea humeri (OCD), and an ununited anconeal process (UAP). Disturbances of enchondral ossification, as well as asynchronous growth of the antebrachial bones and an increased growth rate may provoke abnormal stresses on specific locations such as the medial coronoid process, the anconeal process of the ulna or the humeral trochlea, which may result in ED. Overnutrition with calcium, vitamin D and energy had important influence on rapidity of growth and proneness to ED. ED manifests most often in young dogs less than 1 1/2 year, causing clinical signs such as (intermittent) lameness, pain on movement and altered posture of the affected limb, and radiographically secondary osteoarthrotic changes such as osteophytes or the aforementioned primary lesions. As radiographic projection of the primary lesions FCP and OCD may be difficult in the commonly used mediolateral flexed and craniocaudal views, additional projections such as mediolateral extended or anteroposterior oblique views and alternative diagnostic means such as computed tomography (CT) may be worth considering. Cases of ED are reported in various breeds, though some breeds are especially predisposed and seem to be prone to specific primary lesions. For the German shepherd dog, a breed-predisposition for UAP may be explained by broad chondral junction in association with an accelerated pattern of skeletal maturation. Heritabilities were estimated in a variety of studies, depending strongly on the type of model used. The mode of inheritance is not yet ascertained, but recently the common assumption of a polygenic mode of inheritance for ED is doubted. Instead, genetic independence was supposed between different primary lesions, and also for ED as well as for FCP major gene influence was discussed. So long, phenotypic mass selection was accomplished in different countries most often resulting in a reduced prevalence of ED. The use of best linear unbiased prediction (BLUP) methods including information on relatives and separate evaluation of genetically independent primary lesions may further improve selection against ED.     

Gross and cytological characteristics of normal feline anal-sac secretions

This study was conducted to characterize the gross and cytological characteristics of secretions from normal feline anal sacs. Thirty cats with no recent history of anal-sac disease were selected consecutively and their anal sacs manually expressed. The color, cell counts, or presence of solid portions of the secretions in the youngest cats (<1 year old) were not significantly different from the rest. Young cats (<1 year old) tended to more often have watery secretions. The secretions contained 13 (median) epithelial cells per 600x magnification microscopic field, basophilic background debris, and a mixture of Gram-positive cocci (83 per field; median), Gram-negative cocci (38 per field; median), and Gram-negative rods (1.8 per field; median). Most secretions had occasional neutrophils, and a minority of cats had occasional yeasts in their secretion. Erythrocytes were found only rarely. Extreme heterogeneity existed in gross color, consistency, and amount of solid material. Hence, these latter parameters would not be valid indicators of anal-sac disease.     

Contrastive prevalence of feline retrovirus infections between northern and southern Vietnam

The prevalence of infections with three feline retroviruses; feline leukemia virus (FeLV), feline immunodeficiency virus (FIV) and feline foamy virus (FeFV), was examined in domestic cats (Felis catus) and leopard cats (Felis bengalensis) in southern Vietnam in 1998. We then compared this data with our previous study in northern Vietnam in 1997. None of the cats had FeLV antigens in both the northern and southern areas. In contrast, there is a great distinction in the seropositivity of FIV. Twenty-two percent of domestic cats had FIV antibodies whereas no FIV positive cats were detected in northern area. FIV may have entered southern Vietnam recently and spread rapidly. FeFV infections were found in both areas, suggesting that FeFV might be present in the cat populations in Vietnam from the earliest time.