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Background: It is doubtful that any of the treatments proposed for feline leukaemia virus (FeLV) infection are effective, despite the entity being described 60 years ago. Methods: Eighteen pet cats with progressive FeLV infections were recruited in Australia. One or more antiviral drugs were trialled in 16 cats, while two FeLV‐infected cats were not handleable and served as untreated controls. Six cats were administered RetroMAD1™ only (0.5 mg/kg orally twice daily), a commercially available recombinant chimeric protein with proposed antiretroviral activity. Three cats were administered the integrase inhibitor raltegravir only (10–15 mg/kg orally twice daily), a drug used as a component of highly effective antiretroviral therapy for human immunodeficiency virus (HIV‐1) infection. Three cats were administered RetroMAD1™ and raltegravir concurrently, and four cats were administered raltegravir and the reverse transcriptase inhibitor zidovudine (AZT, 5 mg/kg orally twice daily) concurrently. FeLV RNA and p27 antigen loads were measured at two timepoints (T1‐2 months and T3‐5 months) during therapy and compared to baseline (pretreatment) levels, to assess the response to therapy using linear modelling. The median survival time (MST) of the cats from commencement of FeLV treatment to death was also determined and compared between treatments. Results: The MST for the 16 FeLV‐positive cats which received antiviral therapy was 634 days, while the MST from FeLV diagnosis to death for the two untreated control cats was 780 days. In cats treated with RetroMAD1™, FeLV viral load decreased from T0 to T1‐2 months (median viral load reduced from 1339 × 106 to 705 × 106 copies/mL plasma; P = 0.012), but MST was reduced compared to cats not given RetroMAD1™ (426 days vs 1006 days; P = 0.049). Cats treated with raltegravir and AZT had no significant changes in FeLV viral load over time, but p27 antigen load was decreased from T0 to T3‐5 months in cats treated with raltegravir (median p27 antigen level reduced from 50.2% to 42.7%; P = 0.005). All other results were not significantly affected by the treatment provided. Importantly, statistically significant and substantial associations were found between age at FeLV diagnosis and survival time (P = 0.046, R2 = 18.6) and between FeLV viral load at T0 and survival time (P = 0.004, R2 = 44.4). Younger cats, and cats with higher levels of pretreatment FeLV RNA, had reduced survival times. Cats treated with RetroMAD1™ were typically younger (median age 2.0 vs 8.0 years), likely explaining the observed reduction in MST. A significant association was found between FeLV viral load and p27 antigen load at T0 (P = 0.015, R2 = 32.9). Conclusions: Results from this small case series do not provide convincing support for the use of RetroMAD1™, raltegravir or AZT, alone or in combination, for the treatment of cats progressively infected with FeLV. The changes observed were biologically insignificant. Age and FeLV viral load at diagnosis are useful prognostic markers, and p27 antigen concentration can be used to predict viral load. Larger field trials should be performed examining antiretroviral therapy in FeLV‐positive cats with progressive infections, preferably using three or more drugs from at least two classes, as is standard with human antiretroviral therapy. Future studies would be easier in countries with a higher prevalence of FeLV infections than Australia. [ABSTRACT FROM AUTHOR]

Background Thyrotropin (TSH) can be increased in humans with primary hypoadrenocorticism (HA) before glucocorticoid treatment. Increase in TSH is a typical finding of primary hypothyroidism and both diseases can occur concurrently (Schmidt's syndrome); therefore, care must be taken in assessing thyroid function in untreated human patients with HA. Objective Evaluate whether alterations in cTSH can be observed in dogs with HA in absence of primary hypothyroidism. Animals Thirty dogs with newly diagnosed HA, and 30 dogs in which HA was suspected but excluded based on a normal ACTH stimulation test (controls) were prospectively enrolled. Methods cTSH and T4 concentrations were determined in all dogs and at selected time points during treatment (prednisolone, fludrocortisone, or DOCP) in dogs with HA. Results cTSH concentrations ranged from 0.01 to 2.6 ng/mL (median 0.29) and were increased in 11/30 dogs with HA; values in controls were all within the reference interval (range: 0.01-0.2 ng/dL; median 0.06). There was no difference in T4 between dogs with increased cTSH (T4 range 1.0-2.1; median 1.3 μg/dL) compared to those with normal cTSH (T4 range 0.5-3.4, median 1.4 μg/dL; P=0.69) and controls (T4 range 0.3-3.8, median 1.8 μg/dL; P=0.35). After starting treatment, cTSH normalized after 2-4 weeks in 9 dogs and after 3 and 4 months in 2 without thyroxine supplementation. Conclusions and Clinical Relevance Evaluation of thyroid function in untreated dogs with HA can lead to misdiagnosis of hypothyroidism; treatment with glucocorticoids for up to 4 months can be necessary to normalize cTSH. [ABSTRACT FROM AUTHOR]

Background Canine babesiosis, caused by Babesia canis, is a prevalent and clinically relevant disease in Europe. Severe acute babesiosis is characterized by a high mortality but prognosis is not always correlated with clinical signs nor with the level of parasitemia. Objective This study evaluated prognostic markers associated with poor outcomes in acute Babesia canis infections. Animals and Methods We compared the results of routine laboratory profiles, hand-held lactate and glucose analyzer, and the acute phase response in 2 groups of naturally infected dogs (7 survivors and 8 nonsurvivors). Samples were collected at the time of first admission and before any treatment. Subsequently, the course of prognostic markers was followed in 3 dogs experimentally inoculated with B. canis. Results Nonsurvivors showed significantly higher concentrations of lactate, triglycerides and phosphate and lower hematocrit, leukocyte counts, total serum protein concentrations, and thrombocyte counts when compared to survivors. All nonsurvivors (8/8) had hyperlactatemia, whereas most survivors (6/7) had values within the reference range. All survivors had leucocyte counts within the reference range, unlike the nonsurvivors, which showed leukopenia. During the course of acute babesiosis, the variables serum lactate, triglyceride, and phosphate concentrations, and thrombocyte count only exceeded a prognostic threshold during acute crisis. Conclusions and clinical importance Poor outcome in acute B. canis infection is indicated by changes in the laboratory profile. Intensive care should be considered for dogs presenting with moderate anemia, severe thrombocytopenia, mild to moderate leukopenia, hyperlactatemia, moderately increased serum phosphate, and triglyceride concentrations, and moderately decreased total serum protein concentrations. [ABSTRACT FROM AUTHOR]

Background The ACTH stimulation test is used to evaluate the adrenocortical reserve. Recently, the availability of the synthetic ACTH formulation was limited, causing major problems in clinical practice. Objectives The objective of this study was to evaluate poststimulation peak cortisol concentrations and the duration of the stimulatory effect of a depot ACTH preparation in dogs. Animals Twenty-two healthy dogs, 10 dogs with suspected hypoadrenocorticism ( HA) and 15 dogs with suspected hyperadrenocorticism ( HC). Methods Prospective study. An ACTH stimulation test using a synthetic depot tetracosactide, administered intramuscularly (5 μg/kg or at least 0.1 mL) was performed. Blood samples for determination of cortisol were taken immediately before and 1, 2, 3, 4, 6, and 24 hours after stimulation. Results Peak cortisol concentrations were reached after 2-4 hours in all dogs. Cortisol concentrations 1 hour after stimulation were >9 μg/dL in all healthy dogs and >5 μg/dL in all dogs in which HA was excluded. None of the dogs with HA showed a cortisol-increase above the detection-limit of the assay. After 6 hours, cortisol concentrations had decreased in the healthy and HC group and were back to baseline after 24 hours. Conclusions and Clinical Importance The depot formulation can be used in place of the short-acting ACTH to evaluate the adrenocortical reserve. Blood for peak cortisol concentrations should be drawn 3 hours after stimulation in cases in which HC is suspected; in HA-suspected cases, blood sampling can take place after 1 hour. As the stimulatory effect is gone after 24 hours, interference with other hormonal tests is unlikely after that time. [ABSTRACT FROM AUTHOR]

Background The adrenocorticotropic hormone ( ACTH) stimulation test is the gold standard for diagnosing hypoadrenocorticism ( HA) in dogs. However, problems with the availability of synthetic ACTH (tetracosactrin/cosyntropin) and increased costs have prompted the need for alternative methods. Objectives To prospectively evaluate the cortisol-to- ACTH ratio ( CAR) as a screening test for diagnosing canine HA. Animals Twenty three dogs with newly diagnosed HA; 79 dogs with diseases mimicking HA; 30 healthy dogs. Methods Plasma ACTH and baseline cortisol concentrations were measured before IV administration of 5 μg/kg ACTH in all dogs. CAR was calculated and the diagnostic performance of ACTH, baseline cortisol, CAR and sodium-to-potassium ratios ( SPRs) was assessed based on receiver operating characteristics ( ROC) curves calculating the area under the ROC curve. Results The CAR was significantly lower in dogs with HA compared to that in healthy dogs and in those with diseases mimicking HA ( P < .0001). There was an overlap between HA dogs and those with HA mimicking diseases, but CAR still was the best parameter for diagnosing HA ( ROC AUC 0.998), followed by the ACTH concentration ( ROC AUC 0.97), baseline cortisol concentration ( ROC AUC 0.96), and SPR ( ROC AUC 0.86). With a CAR of >0.01 the diagnostic sensitivity and specificity were 100% and 99%, respectively. Conclusion and Clinical Importance Calculation of the CAR is a useful screening test for diagnosing primary HA. As a consequence of the observed overlap between the groups, however, misdiagnosis cannot be completely excluded. Moreover, additional studies are needed to evaluate the diagnostic reliability of CAR in more dogs with secondary HA. [ABSTRACT FROM AUTHOR]

Background Diagnosis of pheochromocytoma ( PC) is based on a combination of clinical suspicion, finding an adrenal mass, increased plasma, and urine concentrations of catecholamine metabolites and is finally confirmed with histopathology. In human medicine, it is controversial whether biochemically testing plasma is superior to testing urine. Objectives To measure urinary and plasma catecholamines and metanephrines in healthy dogs, dogs with PC, hypercortisolism (HC), and nonadrenal diseases (NAD) and to determine the test with the best diagnostic performance for dogs with PC. Animals Seven PC dogs, 10 dogs with HC, 14 dogs with NAD, 10 healthy dogs. Methods Prospective diagnostic clinical study. Urine and heparin plasma samples were collected and stored at −80°C before analysis using high-pressure liquid chromatography ( HPLC) coupled to electrochemical detection or tandem mass spectrometry were performed. Urinary variables were expressed as ratios to urinary creatinine concentration. Results Dogs with PC had significantly higher urinary normetanephrine and metanephrine : creatinine ratios and significantly higher plasma-total and free normetanephrine and plasma-free metanephrine concentrations compared to the 3 other groups. There were no overlapping results of urinary normetanephrine concentrations between PC and all other groups, and only one PC dog with a plasma normetanephrine concentration in the range of the dogs with HC and NAD disease. Performances of total and free plasma variables were similar. Overlap of epinephrine and norepinephrine results between the groups was large with both urine and plasma. Conclusion and clinical importance Measurement of normetanephrine is the preferred biochemical test for PC and urine was superior to plasma. [ABSTRACT FROM AUTHOR]

Background Determination of the urinary corticoid-to-creatinine ratio ( UCCR) is an important screening test in the diagnosis of hypercortisolism ( HC). However, urinary cortisol metabolites interfere with cortisol measurement in immunoassays, leading to decreased specificity. Gas chromatography-mass spectrometry ( GC- MS) is considered the gold standard for steroid hormone analysis, because it provides a high level of selectivity and accuracy. Objectives To prospectively compare the UCCR of healthy dogs and dogs with HC determined by 5 different immunoassays and by GC- MS and to evaluate the influence of veterinary care on UCCR. Animals Twenty healthy dogs; 18 dogs with HC. Methods Urine was collected in the hospital and again after 6 days at home. Three chemiluminescence immunoassays (Access 2, Beckmann; Immulite 2000, DPC Siemens, with and without trichloromethane extraction) and 2 RIAs (Utrecht in house; Access Beckmann) were used. GC- MS analyses were performed with Agilent 6890N/5973N. Urinary corticoid concentrations were related to urinary creatinine concentrations. Results Immunoassay results were significantly higher compared to GC- MS results. Evaluation of bias plots and clinical assessment made on the basis of the assay results of each dog indicated substantial disagreement among the assays. Sensitivity varied from 37.5 to 75% and with selected assays was lower in samples from day 6 compared to day 0. GC- MS was not superior to the immunoassays in discriminating healthy from HC dogs. Conclusions and Clinical Importance Considerable variation must be anticipated comparing different urinary cortisol assays. Establishing an assay- and laboratory-specific reference range is critical when using UCCR. [ABSTRACT FROM AUTHOR]

Background Transdermal methimazole is an acceptable alternative to oral treatment for hyperthyroid cats. There are, however, no studies evaluating the duration of T4 suppression after transdermal methimazole application. Such information would be valuable for therapeutic monitoring. Objective To assess variation in serum T4 concentration in hyperthyroid cats after once- and twice-daily transdermal methimazole administration. Animals Twenty client-owned cats with newly diagnosed hyperthyroidism. Methods Methimazole was formulated in a pluronic lecithin organogel-based vehicle and applied to the pinna of the inner ear at a starting dose of 2.5 mg/cat q12h ( BID group, 10 cats) and 5 mg/cat q24h ( SID group, 10 cats). One and 3 weeks after starting treatment, T4 concentrations were measured immediately before and every 2 hours after gel application over a period of up to 10 hours. Results Significantly decreased T4 concentrations were observed in week 1 and 3 compared with pretreatment concentrations in both groups. All cats showed sustained suppression of T4 concentration during the 10-hour period, and T4 concentrations immediately before the next methimazole treatment were not significantly different compared with any time point after application, either in the BID or SID groups. Conclusions Because transdermal methimazole application led to prolonged T4 suppression in both the BID and SID groups, timing of blood sampling does not seem to be critical when assessing treatment response. [ABSTRACT FROM AUTHOR]

Abstract: Lice may serve as biological or mechanical vectors for various infectious agents. To investigate louse infestation of ruminants and pigs, and pathogens potentially transmitted by them, anopluran lice (n =1182) were collected in Hungary, and evaluated for the presence of anaplasma, rickettsia and haemotropic mycoplasma DNA. On cattle the following species were found: Linognathus vituli (57%), Haematopinus eurysternus (38%) and Solenopotes capillatus (5%). L. vituli had a lower mean individual count/host when compared to H. eurysternus. On calves only L. vituli was observed, with a higher louse burden than on full-grown cattle. H. eurysternus and S. capillatus were more likely to occur simultaneously with another species on the same host, than L. vituli. Goats infested with Linognathus stenopsis had the overall highest prevalence (68%), while pigs harbouring Haematopinus suis showed the lowest (<1%). Anaplasma DNA was detected in 50% of pools analysed. In L. vituli Anaplasma ovis (or a closely related novel Anaplasma marginale genotype) was identified. Anaplasma-positivity of H. suis suggests that pigs may extend the reservoir and/or host spectrum of relevant species. Anaplasma-infected L. stenopsis pools show for the first time that caprine anaplasmosis is endemic in Hungary. Rickettsia spp. were demonstrated from Linognathus spp. and H. eurysternus. No haemotropic mycoplasmas were detected in any samples. In conclusion, this is the first molecularly confirmed report of bovine and ovine Anaplasma spp. in L. vituli, L. stenopsis and H. suis. The present results suggest that phthirapterosis of domestic animals deserves more attention, and lice should be evaluated among the broad range of potential vectors of arthropod-borne pathogens. [ABSTRACT FROM AUTHOR]

Background: Various protocols using different doses of recombinant human thyrotropin (rhTSH) in TSH stimulation testing have been described. However, the influence of TSH dosage on thyroxine (T4) concentration has not yet been evaluated in suspected hypothyroid dogs. Objective: To evaluate the effectiveness of 2 doses of rhTSH. Animals: Fifteen dogs with clinical signs consistent with hypothyroidism and abnormal stimulation results with 75 μg rhTSH and 18 clinically healthy dogs. Methods: All dogs were stimulated with 75 and 150 μg rhTSH IV in a 1st and 2nd stimulation test, respectively. Blood samples were taken before and 6 hours after rhTSH administration for determination of total T4 concentration. Results: Using the higher dose led to a normal test interpretation in 9 of the 15 dogs, in which stimulation had been abnormal using the lower dose. Based on follow-up information, hypothyroidism was excluded in 7 of these 9 dogs. In all 6 dogs with a blunted response to the higher dose, hypothyroidism could be confirmed. Healthy dogs showed significantly higher post-TSH T4 concentrations with the higher compared with the lower dose. Post-TSH T4 concentrations after TSH stimulation were not related to dogs' body weight in either healthy or diseased dogs. Conclusions and Clinical Relevance: TSH dose significantly influenced test interpretation in suspected hypothyroid dogs. Differentiation between primary hypothyroidism and nonthyroidal disease was improved with 150 μg rhTSH. Because this effect was independent of the dogs' body weight, the higher dose is recommended in dogs that have concurrent disease or are receiving medication. [ABSTRACT FROM AUTHOR]

Two cases of feline leukaemia virus (FeLV)-associated dermatosis are described. The first cat was affected by an ulcerative dermatitis identified as a giant-cell dermatosis. The second case was a cutaneous lymphoma. In both cases, FeLV antigens and FeLV genome were demonstrated in the affected skin immunologically and with polymerase chain reaction, respectively. The first case suggests that, like other retroviruses, at least some strains of FeLV can induce syncytium formation. As FeLV antigens and genome were demonstrated in a serologically negative cat, the second case suggests that focal skin FeLV replication may occur. FeLV-associated dermatoses are rare skin conditions that may be under-diagnosed. [ABSTRACT FROM AUTHOR]

Total immunoglobulin content and concentration of immune complexes (IC) were determined in the sera of 51 cats infected with feline immunodeficiency virus (FIV) and of 40 controls. IgG and IgM were quantified by radial immunodiffusion and circulating IC (CIC) by the CIC-conglutinin assay. IgG fractions were obtained by acid elution from kidney tissues of 15 FIV-infected and five negative control cats to investigate the possible role of IC in the genesis of renal damage observed in infected animals. Mean concentrations of IgG and circulating IC were higher in FIV-infected cats than in controls (29.6± 6.7 versus 23.0 ± 1.9mg/dl (mean ± s.d.) P < 0.001; and 66.5 ± 17.0 versus 27.4± 19.9% I, P < 0.001, respectively), while IgM levels were only slightly increased (0.9 ± 0.05 versus 0.87 ± 0.04 mg/dl, P < 0 02). Immunoglobulin fractions were eluted from 10 of the 15 renal tissue samples from FIV-infected cats and were found to be polyclonal and at least partly specific for FIV antigens. These findings confirm the presence of a B cell activation in FIV infected cats and demonstrate the presence of high levels of CIC in their sera. The presence of immune deposits in renal tissues suggests that IC might play a role in the pathogenesis of the renal damage observed in FIV-infected cats. [ABSTRACT FROM AUTHOR]

Abstract: The present study was carried out in a herd with concurrent infections of Mycoplasma wenyonii and ‘Candidatus M. haemobos’, to investigate if transplacental and/or vector-borne transmission is possible for one or both bovine haemoplasma species. For this purpose blood samples were collected from 38 mother animals and their newborn calves; as well as from 17 uninseminated cows twice three months apart. In addition, 311 mosquitoes and blood-sucking flies (Diptera: Culicidae, Tabanidae, Muscidae) were cought near the animals. DNA was extracted from all samples, followed by real-time PCR analysis. In 10.5% of neonate calves, that were born to cows harbouring both haemoplasmas, M. wenyonii and/or ‘Candidatus M. haemobos’ positivity was detected. Copy numbers in positive samples from cows and their calves indicated that – in comparison with M. wenyonii – ‘Candidatus M. haemobos’-bacteraemia had usually lower levels. In samples of uninseminated cows the rate of infection with the latter species decreased. These findings may explain why M. wenyonii was significantly more frequently detected in blood-sucking flies, than ‘Candidatus M. haemobos’. In conclusion, molecular evidence is provided for the first time on the transplacental transmission of bovine haemoplasmas. Regarding their spread by blood-sucking arthropods, new potential vectors were identified, i.e. the horn fly (Haematobia irritans), the stable fly (Stomoxys calcitrans) and two species of horse flies (Tabanus bovinus, T. bromius). [Copyright &y& Elsevier]

Abstract: The purpose of this investigation was to characterize the shedding pattern of feline leukemia virus (FeLV) RNA in saliva, and to correlate it with the proviral load in whole blood, viral load in plasma, levels of p27 in saliva and plasma, the isolation of infectious FeLV from saliva, and the titers of FeLV-specific antibodies of the IgG and IgA isotypes. We evaluated 24 experimentally FeLV-infected cats for these parameters using real-time RT-PCR and PCR, cell culture assay and sandwich ELISA. We observed that shedding of viral RNA in saliva was a consistent feature in viremic cats. Latently FeLV-infected cats, displaying a very low proviral load, did not shed infectious virus in saliva, but occasionally shed viral RNA. Consequently, salivary shedding of FeLV RNA may not necessarily indicate a transmission potential for susceptible cats. This study also confirmed previous results from our laboratory, showing that a negative result for p27 in plasma, or for viral RNA in plasma or saliva does not exclude FeLV infection, considering that blood cells from those cats contained provirus. We also showed that FeLV RNA and DNA were stable for more than 64 days in saliva samples stored at room temperature. We conclude that the detection of FeLV RNA in saliva may be a useful indicator of viremia, and that the detection of salivary viral RNA by RT-PCR could become a reliable tool for the diagnosis of FeLV infection, which is facilitated by the low invasive method of collection of the samples. [Copyright &y& Elsevier]