Repeatability and reproducibility of microscopic examination of adhesive tape strip cytology slides for the quantification of Malassezia spp. in canine skin.

BACKGROUND: The optimal microscopic magnification and number of optical fields of adhesive tape strip cytological slides that should be examined when searching for Malassezia yeasts on canine skin are unknown. OBJECTIVES: To determine the optimal magnification and the minimum number of optical fields that should be examined to maximise intraobserver repeatability and interobserver reproducibility. MATERIALS AND METHODS: Seven experienced examiners counted, twice, the number of yeasts in 10, 20, 30, 40 and 50 optical fields of 40 slides at ×400 and ×1000 magnification. RESULTS: The number of yeasts per unit surface area was significantly higher at ×1000 compared to ×400 magnification. Repeatability and reproducibility for counting the yeasts was very poor. CONCLUSIONS AND CLINICAL RELEVANCE: Adhesive tape strip cytological slides should be examined microscopically for Malassezia spp. at ×1000 magnification. The repeatability of this examination for counting the yeasts is poor.

Contexte - Le grossissement microscopique optimal et le nombre de champs optiques des lames cytologiques de bandes adhésives à examiner lors de la recherche de levures Malassezia sur la peau de chien sont inconnus. Objectifs - Déterminer le grossissement optimal et le nombre minimal de champs à examiner pour maximiser la répétabilité intra-observateur et la reproductibilité inter-observateur. Matériels et méthodes - Sept examinateurs expérimentés ont compté, deux fois, le nombre de levures dans 10, 20, 30, 40 et 50 champs de 40 lames aux grossissements ×400 et ×1 000. Résultats - Le nombre de levures par unité de surface était significativement plus élevé au grossissement ×1 000 par rapport au grossissement ×400. La répétabilité et la reproductibilité du comptage des levures étaient très médiocres. Conclusions et pertinence clinique - Les lames cytologiques de bandes adhésives doivent être examinées au microscope pour Malassezia spp. à un grossissement ×1 000. La répétabilité de cet examen de comptage des levures est faible.

Introducción- se desconoce el aumento microscópico óptimo y el número de campos ópticos de los portaobjetos citológicos en tiras de cinta adhesiva que deben examinarse al buscar levaduras Malassezia en la piel canina. Objetivos- determinar el aumento óptimo y el número mínimo de campos ópticos que deben examinarse para maximizar la repetibilidad intraobservador y la reproducibilidad interobservador. Materiales y métodos- siete examinadores experimentados contaron dos veces el número de levaduras en campos ópticos de 10, 20, 30, 40 y 50 de 40 portaobjetos con aumentos de x ×400 y ×1000. Resultados- el número de levaduras por unidad de superficie fue significativamente mayor con un aumento de ×1000 en comparación con un aumento de ×400. La repetibilidad y reproducibilidad para contar las levaduras fue muy pobre. Conclusiones y relevancia clínica - Los portaobjetos citológicos en tiras de cinta adhesiva deben examinarse microscópicamente para detectar Malassezia spp. con un aumento de ×1.000. La repetibilidad de este examen para contar las levaduras es pobre.

Contexto - A ampliação microscópica ideal e o número de campos ópticos das lâminas citológicas de fita adesiva que devem ser examinados nas pesquisas de leveduras do gênero Malassezia em cães são desconhecidos. Objetivos - Determinar a magnificação ideal e o número mínimo de campos ópticos que devem ser examinados para maximizar a repetibilidade intraobservador e a reproducibilidade interobservador. Materiais e métodos - Sete examinadores experientes contaram duas vezes o número de leveduras em 10, 20, 30, 40 e 50 campos ópticos de 40 lâminas nas magnificações de x400 e x1000. Resultados - O número de leveduras por unidade de área de superfície foi significativamente maior em x1000 em comparação com a ampliação de x400. A repetibilidade e a reprodutibilidade para a contagem de leveduras foi muito pobre. Conclusões e relevância clínica - Lâminas de citologia por fica adesiva devem ser examinadas microscopicamente para Malassezia spp a uma magnificação de x1.000. A repetibilidade deste exame para contagem de leveduras foi pobre.

A field trial of spinosad for the treatment and prevention of flea infestation in shepherd dogs living in close proximity to flea-infested sheep.

BACKGROUND: Three flea species, Pulex irritans, Ctenocephalides canis and C. felis parasitize shepherd dogs living on sheep farms in Greece. The aim of this randomized, blinded, placebo-controlled trial was to examine the efficacy of spinosad, when administered three times every 4 weeks, as the only intervention to treat and prevent flea infestations in shepherd dogs living on sheep farms. METHODS: Thirty dogs living on sheep farms and infested by at least 24 fleas were randomly allocated into equal groups. Group A dogs received spinosad (45-70 mg/kg body weight), every 4 weeks for three administrations, whereas Group B dogs were placebo-treated. Flea counting was performed at the beginning of the trial (day 0) and after 14, 28, 56 and 84 days. The first five fleas from each dog and 2-6 fleas collected from 5-11 sheep were used for species identification. RESULTS: The percentage of dogs with zero flea counts was significantly higher in group A than in group B at days 14, 28, 56 and 84 and flea counts were significantly lower in group A than in group B at days 14, 28, 56 and 84. In group A, flea counts were significantly lower at days 14, 28, 56 and 84 compared to day 0 whereas there were no changes in flea counts of group B dogs. The percent efficacy of spinosad for the treatment and prevention of flea infestation was higher than 98% (arithmetic means) or higher than 99% (geometric means) throughout the study. No adverse reactions were recorded. C. canis was the predominant flea species of dogs at day 0. In group A the relative abundance of C. felis increased at day14 whereas in group B the relative abundance of P. irritans increased at days 14, 28, 56 and 84. CONCLUSIONS: Spinosad is safe and effective for the treatment of C. canis and C. felis infestations and for the prevention of P. irritans, C. canis and C. felis infestations in shepherd dogs living in close proximity to sheep.

Synovial fluid cytology in experimental acute canine monocytic ehrlichiosis (Ehrlichia canis).

Evidence-based information of a cause-and-effect relationship between Ehrlichia canis infection and polyarthritis in naturally- or experimentally-infected dogs is currently lacking. The aim of this prospective study was to investigate whether synovial fluid cytological evidence of arthritis could be documented in dogs with acute monocytic ehrlichiosis. Direct synovial fluid cytology smears from eight Beagle dogs experimentally infected with E. canis were examined prior to, and on 21, 35 and 63 days post-inoculation. The cytological variables assessed included cellularity, percentages of mononuclear cells and neutrophils, macrophage reactivity and evidence of E. canis morulae. The median cellularity and percentages of mononuclear cells and neutrophils prior to inoculation did not differ when compared to post-inoculation cytological evaluation. Increased cellularity, E. canis morulae or cytological evidence of arthritis or macrophage reactivity were not observed throughout the course of the study. In the present study, no cytological evidence of arthritis was found in dogs with experimental acute canine monocytic ehrlichiosis, suggesting that E. canis infection should be considered a rather uncommon cause of arthritis in dogs.

Prospective evaluation of serum pancreatic lipase immunoreactivity and troponin I concentrations in Leishmania infantum-infected dogs treated with meglumine antimonate.

Canine leishmaniosis (CanL) caused by Leishmania infantum is an important zoonotic disease. One of the most commonly used drugs for the treatment of CanL is meglumine antimonate. Drugs of this class have been associated with pancreatitis and cardiotoxicity in humans infected with Leishmania spp. The aim of this study was to measure serum canine pancreatic lipase immunoreactivity (Spec cPL) and cardiac troponin I (cTnI) concentrations in dogs with leishmaniosis during treatment with meglumine antimonate, and to compare them with those of dogs with leishmaniosis not treated with this drug. A total of 30 non-uremic dogs with leishmaniosis, living in Greece, were prospectively enrolled into the study. Of the 30 dogs, 20 (Group A) were treated with a combination of meglumine antimonate (100mg/kg, SC, q24 h) and allopurinol (10mg/kg, PO, q12h) for 28 days, while 10 dogs (Group B) were treated with allopurinol alone (10mg/kg, PO, q12h) for 28 days. Blood samples were collected at timepoint 0 (before treatment) and at 14 and 28 days after the initiation of treatment. None of the dogs treated with meglumine antiomonate had a Spec cPL concentration suggestive of pancreatitis (≥ 400 µg/L) or clinical signs suggestive of pancreatitis at any of the timepoints. Similarly, none of the dogs treated with meglumine antiomonate had a serum cTnI concentration above the upper limit of the reference range (>0.5 ng/mL) or clinical evidence of cardiotoxicity at any of the 3 timepoints. In the present study, meglumine antimonate treatment in dogs with leishmaniosis did not result in clinical or laboratory evidence of either pancreatitis or cardiotoxicity.

Comparison of two commercial rapid in-clinic serological tests for detection of antibodies against Leishmania spp. in dogs.

Antibodies against Leishmania spp. are detected in most dogs with clinical signs of leishmaniasis due to Leishmania infantum. Accurate, rapid in-clinic serological tests may permit immediate confirmation of the diagnosis and implementation of therapeutic measures. The aim of the current study was to evaluate the diagnostic accuracy of 2 commercial, rapid in-clinic serological tests for the detection of anti-Leishmania antibodies in sera of dogs, the Snap Canine Leishmania Antibody Test kit (IDEXX Laboratories Inc., Westbrook, Maine) and the ImmunoRun Antibody Detection kit (Biogal Galed Labs, Kibbutz Galed, Israel), using indirect fluorescent antibody test (IFAT) as the reference method. A total of 109 sera collected from 65 seropositive and 44 seronegative dogs were used. The sensitivities of the Snap and ImmunoRun kits were 89.23% (95% confidence interval: 79.05-95.54%) and 86.15% (95% confidence interval: 75.33-93.45%), respectively, and the specificity of both tests was 100%. A good agreement between each of the rapid in-clinic serological tests and IFAT and between the 2 rapid in-clinic serological tests was witnessed. Both rapid in-clinic serological tests showed an adequate diagnostic accuracy and can be used for the fast detection of antibodies against L. infantum in dogs.

Thyroid function in 36 dogs with leishmaniosis due to Leishmania infantum before and during treatment with allopurinol with or without meglumine antimonate.

Hypothyroidism may predispose to the development of canine leishmaniosis or it may appear during the course of the latter due to infiltration and destruction of the thyroid gland by infected macrophages. The main purpose of this study was to evaluate thyroid function through measurement of serum total thyroxin (tT4), free thyroxin (fT4), and canine thyroid stimulating hormone (cTSH) concentrations in 36 dogs with leishmaniosis, before and after 2 and 4 weeks of treatment with allopurinol with or without meglumine antimonate. Before treatment 27/36 (75%) dogs had serum tT4 concentrations below the lower limit of the reference interval but only 2 of them had concurrently serum fT4 concentrations below the lower limit of the reference interval and none had increased serum cTSH concentrations. During treatment there were no significant changes in serum tT4 or fT4 concentrations, whereas a significant increase in serum cTSH was observed. Two dogs had decreased serum tT4 and fT4 but normal cTSH concentrations before treatment and two other dogs had decreased serum tT4 and increased cTSH, but normal fT4 concentrations during the treatment period. Although hypothyroidism could not be definitively excluded in these dogs it is considered unlikely based on their overall hormonal profile, clinical presentation, and response to treatment. Therefore, hypothyroidism does not appear to be an important predisposing disease or a frequent complication of canine leishmaniosis.

Regional parasite density in the skin of dogs with symptomatic canine leishmaniosis.

In canine leishmaniosis, the parasitic density of the skin may be important for the infection of sandflies, and increased accumulation of inflammatory cells infected with Leishmania is believed to occur in dermal areas subjected to mechanical trauma. Parasite density and inflammatory responses in the upper and lower dermis of three body sites: flank (control site), dorsal muzzle (sandfly feeding site), and footpads (mechanical stress sites) were thus investigated in 15 dogs with symptomatic leishmaniosis. Parasite density did not differ between the control and tested sites or between the upper and lower dermis, apart from the footpads where it was higher in the upper dermis, and there was no correlation with severity of the macroscopic lesions or inflammatory infiltrate, except for the lower footpad dermis. No selective accumulation of the parasite in the muzzle that would favour its transmission to sandflies occurred, and the mechanical stress imposed on the footpads was not associated with increased parasitic density, or with inflammatory infiltrate.

Giant hypertrophic gastritis (Menetrier's-like disease) in an Old English sheepdog.

An 11-year-old, male Old English sheepdog was admitted for weight loss and intermittent vomiting of 1 month's duration. A cranioventral abdominal mass, anemia, hypoproteinemia, and hypoalbuminemia were the prominent abnormal findings. Imaging studies identified a remarkably thickened gastric wall with multilobulated folds protruding into the gastric lumen. Gastrotomy revealed the presence of giant cerebriform rugal folds arising from the fundus and body of the stomach. Pronounced gastric glandular hyperplasia and lack of evidence of cellular atypia were suggestive of giant hypertrophic gastritis. The dog was treated with prednisolone, cimetidine, and hyoscine butylbromide, only to experience a short-term remission.

Type of smear may influence thrombopoietic cell counts in the bone marrow of clinically healthy dogs.

BACKGROUND: The expected number of thrombopoietic cells in normal canine bone marrow is poorly defined and there is no consensus on the most appropriate way to prepare cytologic smears to evaluate these cells nor on the optimum method for their quantification. OBJECTIVE: The purpose of this study was to determine total and differential counts of thrombopoietic cells in the bone marrow of clinically healthy Beagle dogs by comparing 4 different smear types and bone marrow core biopsies. METHODS: Twenty-two clinically healthy, male Beagle dogs, 10 to 12 months old, were used in the study. Following bone marrow aspiration and core biopsy from the iliac crest, Giemsa-stained smears were prepared by 4 techniques: drop-squash, particle-squash, buffy coat, and fat-layer smears. Thrombopoietic cells were counted in up to 100 low-power fields (LPF, X10 objective) in the aspiration smears and in all possible high-power fields (HPF, X40 objective) in H&E-stained biopsy sections. RESULTS: Mean total thrombopoietic cell counts were 2.76 cells/LPF (drop-squash), 1.55 cells/LPF (particle-squash), 8.05 cells/LPF (buffy coat), and 3.08 cells/LPF (fat-layer). Core biopsies yielded 5.31 cells/HPF but frequently failed to provide interpretable specimens. There was a significant difference in cell counts among the 4 smear types (P <.001). Based on evaluation of buffy coat smears, thrombopoietic cells included 1.23% megakaryoblasts, 8.77% promegakaryocytes, and 90% megakaryocytes, with a mean maturation index of 0.11. CONCLUSION: Thrombopoietic cell counts in canine bone marrow are influenced by the smear technique. Buffy coat and fat-layer smears may be useful to obtain cellular smears in hemodiluted or small aspirate samples.