Effect of Enterococcus faecium SF68 on serum cobalamin and folate concentrations in healthy dogs.

OBJECTIVE: To study the effect of a 14-day administration of the probiotic Enterococcus faecium SF68 on serum concentrations of cobalamin and folate in healthy dogs. MATERIALS AND METHODS: Thirty-six healthy dogs were randomly allocated between probiotic and control groups. Enterococcus faecium SF68 was administered to the probiotic group for 14 days whereas the control group did not receive any product. A blood sample was taken from all dogs when starting the administration (day 1), when the administration ended (day 14) and 14 days later (day 28). Serum cobalamin and folate concentrations and the canine inflammatory bowel disease activity index scores were determined at each time point. RESULTS: There was a progressive reduction of mean serum cobalamin in the probiotic group during the 28-day study, with significantly lower concentration at day 28 compared to baseline and day 14 concentrations. Moderate hypocobalaminaemia was observed in eight dogs at day 28. Probiotic administration was associated with a non-significant increase in mean serum folate concentration at day 14, and a significant decrease at day 28 compared with day 1. The canine inflammatory bowel disease activity index score remained unaltered during the study. CLINICAL SIGNIFICANCE: Short-term Enterococcus faecium SF68 administration caused a significant reduction of mean cobalamin concentration and moderate hypocobolaminaemia in eight of 18 dogs. Monitoring serum folate appears unnecessary because the probiotic caused a non-significant increase that returned to baseline values after administration was discontinued.

Mucoperiosteal exostoses in the tympanic bulla of African lions (Panthera leo).

Mucoperiosteal exostoses (MpEs) of the tympanic bulla (TB), also referred as middle-ear otoliths, have been occasionally described in dogs and cats in association with clinical signs of otitis media or as an incidental finding, but they have not been recorded in other species. In this report, we describe the radiographic, gross, and histopathologic features of MpEs in 8 African lions (Panthera leo). All animals (5 males and 3 females) were adults that had been kept in captivity and had their skeletons conserved as part of an anatomic academic collection. A radiographic study revealed mineralized structures in the TB consistent with MpEs in 7 of the 16 examined TB; a computed tomography study identified MpEs in 12 of the 16 TB. Six TB from 4 lions were sectioned, and several MpEs were demineralized for histopathologic analysis. Grossly, MpEs appeared variable in number and shape. Some were globular structures that were loosely attached to the mucosal surface of the TB; others were isolated to coalescent bone spicules extending from the mucoperiosteum. Position was also variable, but MpEs frequently developed in the hypotympanum, especially on the ventromedial aspect of the TB wall. Microscopically, MpEs were composed of osteonal bone growing from the periosteum and not by dystrophic calcification of necrotic tissue debris, as is hypothesized in dogs.

Steroid-sparing effect of mycophenolate mofetil in the treatment of a subepidermal blistering autoimmune disease in a dog.

A 7-year-old female Cocker spaniel-cross was referred with an 8-month history of mucocutaneous erosive dermatitis. On physical examination, skin lesions affected the eyelids and periocular area, lips and vulva. Lesions were symmetrical with small diffuse superficial ulcers, haemorrhagic crusts, adherent purulent exudation in haired skin, and alopecia with hyperpigmentation and scarring. Histopathologic evaluation showed multiple, non-intact dermoepidermal junction vesicles and ulceration associated with a dermal lichenoid infiltrate. Immunohistochemistry showed strong to moderate reactivity in the dermoepidermal junction for the antibodies directed against canine IgG, human IgG lambda light chains and C3, respectively. A diagnosis of autoimmune subepidermal blistering dermatosis was made. Treatment with oral prednisone at 2 mg/kg and mycophenolate mofetil (MMF) at 20 mg/kg twice daily was initiated and after 4 weeks the ulcers and erosions were cured. During the rest of treatment, MMF was maintained at 10 mg/kg twice daily and prednisone could be tapered to 0.25 mg/kg once every other day without recurrences. In conclusion, this case report shows that MMF was well tolerated and might be effective as steroid-sparing agent in the long-term treatment of this autoimmune subepidermal blistering disease.

Effects of different glucocorticoid treatments on serum acute phase proteins in dogs.

The serum concentrations of haptoglobin, caeruloplasmin, C-reactive protein and serum amyloid A were measured in three groups of seven healthy dogs. Group 1 received a single dose of 1.1 mg/kg methylprednisolone acetate, administered subcutaneously; group 2 received 1 mg/kg per day of prednisone administered orally for three weeks; and group 3 received 2.2 mg/kg per day of prednisone administered orally for seven days. Before the administration of the glucocorticoids the serum concentrations of all the acute phase proteins were within the authors' laboratory reference ranges. After the administration of the drugs there were significant increases in the concentration of haptoglobin in all three groups, the increases being larger in groups 2 and 3. In contrast, the concentrations of C-reactive protein, caeruloplasmin and serum amyloid A were not affected.

Duration of increased serum alkaline phosphatase activity in dogs receiving different glucocorticoid doses.

Exposure to exogenous glucocorticoids can variably increase the serum alkaline phosphatase (alp) activity, however, the duration of this effect in dogs has not been determined. In this study, three groups of ten clinically normal adult dogs were administered different types of glucocorticoids at therapeutic doses. Group 1 received prednisone 1 mg kg day(-1)p.o. for 3 weeks; Group 2 received a single dose of methylprednisone acetate 1.1 mg kg day(-1)s.c.; Group 3 received dexamethasone 0.25 mg kg day(-1)p.o. for 1 week. In Group 1 elevations were statistically significant on days 7, 14 and 21 (P<0.01, P<0.001, P<0.001, respectively). After discontinuing therapy serum alp returned to baseline levels in 7 days. In Group 2, serum alp activity remained significantly elevated for 3 weeks after therapy (P<0.05, P<0.001, P<0.01 on days 7, 14 and 21 respectively). In Group 3, serum alp levels were significantly increased after 1 week of therapy (P<0.001) returning to basal levels 2 weeks after discontinuing glucocorticoid administration. In conclusion, duration of increased serum alp activity was variable and with the protocols assessed a 3-week period for short-acting glucocorticoids and more than 4 weeks for long-acting methylprednisone may be required to return to baseline levels in all dogs.

Investigation of antinuclear antibodies in canine atopic dermatitis.

Serum samples from 40 atopic dogs and 20 healthy dogs were assayed for antinuclear antibodies (ANA) using a human epithelial cell line (HEp-2) and standard indirect immunofluorescent methods. Samples from the atopic dogs were grouped according to the presence (n = 28) or absence (n = 12) of facial lesions at any moment during the follow-up period. Positive ANA titres were found in 10 of the 40 atopic dogs analysed (25%) whereas samples from the control group were negative. Eight atopic dogs with facial lesions had a positive titre (28.57%) in contrast with atopic dogs without facial lesions where two positive samples (16.67%) were found; however, the differences were statistically not significant. Endpoint titres were low (1/40), only two samples yielded a 1/80 positive titre and one sample had a 1/320 titre, all of them from the facial lesions group. Response to immunotherapy was classified as positive only in four of the 10 ANA-positive patients (40%) compared with a response rate of 73% (22 of 30) in the ANA-negative atopic dogs. However, a Fisher's exact test showed a two-sided P-value of 0.122 which was considered statistically not significant. The overall response rate to immunotherapy for all atopic dogs was 65% (26 of 40). In conclusion, the prevalence of ANA is higher in atopic than in healthy dogs, especially if facial lesions are present. Although a clinically significant pathogenic contribution is not probable, this higher prevalence should be taken into account in the differential diagnosis of canine autoimmune dermatitis.

Hepatic cirrhosis in a five-month-old dog.

The clinicopathological features of an unusual case of a five-month-old male Spanish mastiff, which was presented with clinical signs indicative of severe hepatic failure, are reported. Fluid replacement therapy, colloid plasma expanders, antibiotics and diuretic drugs were unsuccessful in improving the animal's general condition, and euthanasia was elected by the owner. On necropsy, ascites and severe cirrhosis, with extensive periacinar necrosis, was found. Cirrhosis is a rare lesion in young dogs. The most common causes are circulatory disturbances, hereditary metabolic disorders or poisoning, such as aflatoxicosis and anticonvulsant therapy. The possible involvement of canine adenovirus in this case is discussed.

Effects of haemolysis, lipaemia and bilirubinaemia on prothrombin time, activated partial thromboplastin time and thrombin time in plasma samples from healthy dogs.

Interferences caused by haemolysis, lipaemia and bilirubinaemia on prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT in normal canine plasma samples were studied using commercially available reagents and a steel ball coagulometer. Haemolysis significantly interfered with APTT (P = 0.0076) and TT (P = 0.0292). Regression analysis showed that TT was significantly shortened as haemoglobin concentrations increased. Lipaemia increased as demonstrated by regression analysis. Bilirubin significantly interfered with PT (P=0.0003) and APTT (P=0.002). Although statistically significant, none of the differences found were of clinical relevance.

Effects of dexamethasone administration on serum trypsin-like immunoreactivity in healthy dogs.

OBJECTIVE: To determine whether administration of dexamethasone altered serum trypsin-like immunoreactivity (TLI) in healthy dogs. ANIMALS: 12 healthy dogs. PROCEDURE: Dexamethasone (0.25 mg/kg, p.o., q 24 h) was administered for 7 days. Serum TLI, alpha-amylase and alanine aminotransferase (ALT) activities, and urea and creatinine concentrations were determined on days 0, 7, 14, and 21 of the study. RESULTS: Serum TLI and ALT activities were significantly increased, and serum alpha-amylase activity was significantly decreased after administration of dexamethasone for 7 days. However, values obtained on days 14 and 21 were not significantly different from baseline values. Dexamethasone administration was not associated with any significant changes in serum creatinine or urea concentrations. Serum TLI and alpha-amylase activities were significantly correlated prior to dexamethasone administration. Dogs did not develop clinical signs of pancreatitis. CONCLUSIONS AND CLINICAL RELEVANCE: Dexamethasone administration was associated with an increase in serum TLI. However, values returned to baseline 7 days after dexamethasone administration was discontinued. Serum TLI may be falsely high in dogs that have been treated with dexamethasone in the week preceding analysis.

Effects of short courses of different doses of prednisone and dexamethasone on serum third component of complement (C3) levels in dogs.

The effect of different doses of prednisone and dexamethasone on serum C3 levels was determined in 35 dogs. Dogs in Group A (n = 15) were administered prednisone (1.1 mg/kg/day) for 14 days; dogs in Group B (n = 10) were given prednisone at 2.2 mg/kg/day for 7 days; dogs in group C (n = 10) were administered dexamethasone (0.25 g/kg/day) for 7 days. Serum C3 concentrations were determined using a sandwich ELISA in samples obtained before and after glucocorticoid administration. Concentrations were expressed as a percentage of a reference standard. No statistically significant differences were found after glucocorticoid administration in all groups. Thus, short-term administration of prednisone and dexamethasone at commonly used doses did not result in significantly lower serum C3 levels.

Leishmaniosis and generalized demodicosis in three dogs: a clinicopathological and immunohistochemical study.

This paper describes the clinicopathological and immunohistochemical aspects of the skin lesions in three dogs with leishmaniosis and generalized demodicosis. Diffuse alopecia, crusts, folliculitis and furunculosis, as commonly seen in generalized demodicosis, were prominent in all the dogs. MicroIscopically, there was a diffuse and perifollicular superficial and deep granulomatous dermatitis and, in two dogs, both Copyright Demodex canis mites and Leishmania spp. amastigotes were observed in the same lesions. Numerous Mac387(+)macrophages were observed in the inflammatory infiltrates, but macrophages loaded with amastigotes were Mac387(-). In all cases, immunoreactive CD3 lymphocytes were sparse, both in the granulomatous and perifollicular infiltrates. There were numerous IgG+, IgG4(+)-secreting plasma cells in areas of folliculitis and furunculosis and fewer IgG2(+), IgG3(+), IgA+and IgM+-secreting plasma cells in the inflammatory infiltrate. In all cases, MHC Class II was expressed by the majority of dermal macrophages and dendritic cells, as well as by lymphocytes and fibroblasts. The paucity of CD3(+)lymphocytes, usually abundant in D. canis lesions, points to leishmania-induced cell-mediated immunosuppression as a predisposing factor for generalized demodicosis.

Effects of haemolysis, lipaemia and bilirubinaemia on an enzyme-linked immunosorbent assay for cortisol and free thyroxine in serum samples from dogs.

The possible interference of haemolysis, lipaemia and bilirubinaemia on commercially available enzyme-linked immunosorbent assays (test kits Enzymun-Test; Boehringer Mannheim) for cortisol and free thyroxine (FT4) in canine plasma samples was studied. Serum samples from 20 clinically normal dogs were enriched in vitro with different amounts of fresh haemolysate, lipid and bilirubin and compared with the original sera. The tests were used in connection with the analyser system Enzymum-Test (Boehringer Mannheim) System ES300. Haemolysis significantly (P = 0.039) interfered with the accuracy of FT4 determination independent of haemoglobin concentrations. Thus, haemolysis should be avoided in FT4 testing by competitive enzyme immunoassay. Lipaemia significantly interfered (P = 0.0015) with cortisol determination but not with FT4 determination (P = 0.41). Regression analysis showed that FT4 concentration significantly increased as triglyceride levels increased, especially at concentrations greater than 125 mg dL-1. The positive bias observed was of no diagnostic importance for cortisol results and the increase of FT4 levels could be precisely predicted by linear regression analysis. The addition of bilirubin significantly (P = 0) interfered with cortisol testing but, as with lipaemia, the magnitude of the differences were of no clinical significance.

Evaluation of a commercial ELISA test for the detection of allergen-specific IgE antibodies in atopic dogs.

A commercial enzyme-linked immunosorbent assay (ELISA) designed to detect allergen-specific immunoglobulin (Ig)E antibodies were evaluated in 36 atopic dogs and in 12 normal dogs. The test showed a sensitivity of 72.23% and a specificity of 41.6%. Positive and negative predictive values were 76.47 and 35.71% respectively. Correlation between the ELISA kit results and intradermal skin testing varied depending on the allergen and ranged from 47.1 to 80.4%, although positive correlation (i.e. allergens positive in both tests) ranged rom 2.7 to 19.4%. In conclusion, this serological test gave both false positive and false negative results. Sensitivity, specificity and predictive values indicate that this ELISA may not be useful in canine atopy. Although correlation studies were hampered by the impossibility of using the same allergenic extracts, the correlation observed between intradermal and serological testing indicates that results from both tests are not interchangeable.

Levels of IgM and IgA circulating immune complexes in dogs with leishmaniasis.

The concentrations of IgM and IgA circulating immune complexes (CIC) were determined in 82 dogs with naturally acquired leishmania infection and in a control group of 25 healthy dogs. The mean serum IgM and IgA CIC concentration in infected dogs were significantly (IgM; P < 0.004; IgA; P < 0.000) higher than in the control group. An increase in IgM and IgA CIC concentration was found in 47.6 and 95.1%, respectively, of the leishmania-infected dogs. The serum IgM and IgA CIC concentrations in infected dogs showing hypercreatininaemia were not statistically higher than those of sick dogs with normal creatininaemia. When hypercreatininaemia (> or = 1.30 mg/dl) was used as an indicator for CIC disease, the positive predictive value obtained with 0.368 for IgM CIC and 0.894 for IgA CIC, indicating that renal function impairment was associated with the high serum IgM and IgA CIC concentrations in 36.8 and 89.4%, respectively, of the infected dogs.

Use of allopurinol for maintenance of remission in dogs with leishmaniasis.

Current treatments for infected dogs with leishmaniasis do not always provide long-term control of the disease and clinical relapses are common. In this study, the usefulness of long-term allopurinol administration in the maintenance of clinical remission in canine leishmaniasis was evaluated. Fifteen dogs with natural leishmania infection were subjected to an initial treatment based on the simultaneous administration of meglumine antimoniate (100 mg/kg/day) and allopurinol (30 mg/kg/day). Once clinical remission was achieved, a maintenance treatment with allopurinol (20 mg/kg/day) administered for one week a month was instituted. Results were compared with those of a retrospective control group comprising 15 infected dogs which only followed the induction treatment. Relapses occurred in 86 per cent of control dogs within 14 months of discontinuing treatment. In contrast, those dogs on intermittent oral allopurinol administration were successfully maintained in clinical remission for a follow-up period of 10 to 44 months. In this latter group, specific antibody titres decreased or were unchanged, no side effects directly attributable to allopurinol were seen and treatment was well accepted by the owners. It is concluded that long-term intermittent administration of allopurinol is an effective way of maintaining clinical remission in dogs with leishmaniasis.

Validation of a commercially available enzyme-linked immunosorbent assay (ELISA) for the determination of cortisol in canine plasma samples.

Samples were obtained from clinically normal dogs before and after ACTH stimulation and dexamethasone suppression tests. The test kit Enzymun-Test (Boehringer Mannheim) for determining cortisol concentrations in human plasma was used in connection with the analyser system Enzymun-Test (Boehringer Mannheim) System ES300 following the manufacturer's instructions. The intra-assay and inter-assay coefficients of variation were 1.28% and 5.64%, respectively. The mean recovery when assaying samples with a cortisol content of more than 100 nmol/L was 95.41%, but this percentage decreased in samples with lower cortisol levels. The sensitivity of the assay was 2.76 nmol/L. The results of the ACTH stimulation and dexamethasone suppression tests were similar to those published previously. The ELISA method evaluated allows a precise and sensitive determination of cortisol concentrations in canine plasma samples. The major drawback observed was the loss of accuracy at low cortisol concentrations. Since the assay tends then to report lower cortisol concentrations, the generally accepted concentration of 40 nmol/L may not be suitable as the cutoff value in dexamethasone suppression tests.