Iatrogenic symptomatic hypoadrenocorticism after treatment with trilostane for hyperadrenocorticism in dogs: eight cases (2008-2019).

OBJECTIVES: Trilostane is the medical treatment of choice for hyperadrenocorticism. Iatrogenic hypoadrenocorticism is thought to be rare, with most cases being transient and only a few cases of permanent hypoadrenocorticism have been reported. This study reports findings from eight cases of iatrogenic hypoadrenocorticism and examines the presence of concurrent diseases at the time of diagnosis. MATERIALS AND METHODS: Medical records of dogs treated for hyperadrenocorticism with trilostane since 2008 were reviewed, and cases of clinical iatrogenic hypoadrenocorticism were extracted. Cases were considered permanent if long-term replacement therapy was required. RESULTS: Eight dogs met the inclusion criteria. The time between the beginning of trilostane treatment and the diagnosis of hypoadrenocorticism ranged from 4 days to 13 months, and the dosage of trilostane ranged between 1 and 8 mg/kg/day. Six dogs had a suspicion of concurrent disease at the time of hypoadrenocorticism diagnosis. The trilostane dose was decreased in two dogs; trilostane was withdrawn in one case without further relapse of hyperadrenocorticism; and glucocorticoids with or without mineralocorticoid supplementation were prescribed in five dogs. Two of these five dogs were lost to follow-up, and the other three had a diagnosis of permanent hypoadrenocorticism. Adrenal gland ultrasonography in these three dogs showed a progressive reduction in gland sizes with heterogeneous echogenicity. CLINICAL SIGNIFICANCE: Iatrogenic hypoadrenocorticism is a rare but potentially life-threatening complication of trilostane treatment in dogs with hyperadrenocorticism. The occurrence of a concurrent disease might trigger the development of clinical signs of hypoadrenocorticism in previously subclinical dogs.

Implication, clinical and biological impact of vector-borne haemopathogens in anaemic dogs in France: a prospective study.

OBJECTIVES: To prospectively describe the clinical and biological impact of vector-borne haemopathogens in anaemic dogs in France and occurrence of haemolysis. MATERIALS AND METHODS: This prospective descriptive cohort study includes 134 client-owned dogs that were anaemic on admission at the Veterinary Teaching Hospital of VetAgro Sup, Lyon, France. They underwent comprehensive screening with PCR to detect a panel of vector-borne haemopathogens, SNAP Leishmania and SNAP 4Dx Plus (IDEXX). RESULTS: Vector-borne haemopathogen-associated anaemia accounted for 17·2% (23/134) of anaemic cases. PCR for Babesia species, Mycoplasma species, Anaplasma platys or Ehrlichia canis and positive serology for Leishmania species, occurred in 11/23, 10/23, 2/23, 1/23 and 1/23 cases, respectively. Two dogs had positive PCR for both Babesia and Mycoplasma species. All dogs infected with Mycoplasma species alone had neoplastic disease. Vector-borne haemopathogens were the second most common cause of haemolysis (7/23, 30·4%). In the multivariable regression model, males were overrepresented ( OR : 2·82, P=0·03) and haemolysis ( OR : 3·31, P=0·01) was more frequent in dogs with vector-born haemopathogen-associated anaemia. CLINICAL SIGNIFICANCE: Vector-borne haemopathogens are a common cause of anaemia in this geographical region.

Clinical signs, seasonal occurrence and causative agents of canine babesiosis in France: results of a multiregional study.

Canine babesiosis (or piroplasmosis) is an emerging tick-borne disease caused by intraerythrocytic protozoa of the genera Babesia and Theileria. In dogs, infection by these parasites usually induces a haemolytic syndrome that can be fatal when complicated. Canine babesiosis prevalence is high in France, with Babesia canis thought to be the main etiological agent of the disease. This article presents the results of a multiregional prospective longitudinal survey on canine babesiosis conducted in France from October 2006 to December 2007. A total of 836 cases were reported by veterinarians using a multiple choice questionnaire and blood samples from 70 dogs were analyzed using PCR-RFLP to identify species responsible for canine babesiosis cases across the country. The main clinical signs reported were lethargy (98%), anorexia (98%) and hyperthermia ≥ 39 °C (80%) followed by pale mucous membranes (54%), modification of urine aspect (45%) and splenomegaly (33%). The dog population at risk was mainly represented by young dogs living in rural areas. Twenty-five out of the 70 blood samples (36%) tested by diagnostic PCR were found to contain Babesia/Theileria genus-specific DNA and all had profiles similar to that of Babesia canis genomic DNA after restriction fragment length polymorphism analyses. The survey results provide a reference for further molecular studies to assess the species and vectors involved in the transmission of the disease in France and across the Mediterranean basin.

Causes of anaemia other than acute blood loss and their clinical significance in dogs.

OBJECTIVES: To identify the causes of anaemia, other than acute blood loss, in dogs and to determine whether severity of anaemia provides clues to the diagnosis. METHODS: The veterinary medical database of the Veterinary Campus Hospital, Lyon was searched. Dogs with anaemia (packed cell volume <37%) were included and assigned to different disease groups. Dogs with acute blood loss were excluded. The case records were examined for weakness at presentation, the severity and regeneration of anaemia and the final diagnosis including tumour type if applicable. RESULTS: The case records of 456 dogs with low packed cell volume were included. Cancer-related anaemia and anaemia of inflammatory disease accounted for 33·1 and 28·5% of cases, respectively. Most dogs with cancer-related anaemia had solid tumours (73%). The prevalence of immune-mediated anaemia increased with severity of anaemia (5·3, 15·5, 41·2 and 56·2% for mild, moderate, severe and very severe anaemia, respectively), whereas the prevalence of anaemia of inflammatory disease decreased (36·7, 22·5, 2·9 and 0% for mild, moderate, severe and very severe anaemia, respectively). CLINICAL SIGNIFICANCE: Anaemia of inflammatory disease and cancer-related anaemia were the most frequently identified causes of anaemia in dogs. The percentage of dogs with immune-mediated anaemia increased with anaemia severity, whereas the percentage of dogs with anaemia of inflammatory disease decreased with anaemia severity. Thus, severity of anaemia may provide clues to the diagnosis.

First evidence and molecular characterization of Babesia vogeli in naturally infected dogs and Rhipicephalus sanguineus ticks in southern France.

Babesiosis is an emerging tick-borne disease of animals and humans caused by intraerythrocytic protozoa of the genera Babesia and Theileria. In France canine babesiosis has a high prevalence with Babesia canis thought to be the main aetiological agent of the disease. Babesia vogeli has already been reported to occur in Europe and in other countries around the Mediterranean Sea. The tick Rhipicephalus sanguineus, the main known vector of B. vogeli, occurs in southern France. However, only one case of a B. vogeli infected dog has been reported to date in France. To gain further insight into the prevalence of Babesia and Theileria infections in dogs and ticks of the R. sanguineus complex, a study was conducted in a veterinary practice in the south of France from January to September 2010. Twelve bloods from dogs and 36 R. sanguineus ticks were analyzed using PCR and sequencing. For the analysis of ticks, a new primer was designed to specifically amplify the B. vogeli 18S rRNA gene. Four dogs (33.3%) and 8 ticks (22.2%) were found to be infected with B. vogeli. This approach has thus revealed for the first time a cluster of cases of canine babesiosis caused by B. vogeli in France and highlights the need to systematically screen for pathogens potentially responsible for canine babesiosis at the species level using suitable molecular tools.

"Dendritic cells in different animal species: an overview".

The comprehension of the immune system and the role of DC in the pathological diseases may contribute to their use in veterinary medicine in the prevention and treatment of many diseases. Currently, most dendritic cell (DC) research occurs in the human and murine model systems on the generation of cells from the bone marrow or peripheral blood mononuclear cells (PBMC) cultured in vitro. Despite the lack of available immunological reagents such as antibodies and cytokines, analogous cells have been generated and identified in many different species and reviewed in this study.

Factors associated with upper respiratory tract disease caused by feline herpesvirus, feline calicivirus, Chlamydophila felis and Bordetella bronchiseptica in cats: experience from 218 European catteries.

A full history of the management practices and the prevalence of upper respiratory tract disease (URTD) at 218 rescue shelters, breeding establishments and private households with five or more cats was recorded. Oropharyngeal and conjunctival swabs and blood samples were taken from 1748 cats. The prevalences of feline herpesvirus (FHV), feline calicivirus (FCV), Chlamydophila felis and Bordetella bronchiseptica were determined by PCR on swab samples. An ELISA was applied to determine the prevalence of antibodies to B. bronchiseptica. The rates of detection by PCR of each pathogen in the cats in catteries with and without ongoing URTD were, respectively, FHV 16 per cent and 8 per cent; FCV 47 per cent and 29 per cent; C. felis 10 per cent and 3 per cent; and B. bronchiseptica 5 per cent and 1.3 per cent; the seroprevalences of B. bronchiseptica were 61 per cent and 41 per cent, respectively. There was evidence that FHV, FCV and B. bronchiseptica played a role in URTD. The risk factors associated with the disease were less than excellent hygiene, contact with dogs with URTD, and larger numbers of cats in the cattery or household.

High-grade canine T-cell lymphoma/leukemia with plasmacytoid morphology: a clinical pathological study of nine cases.

The aim of this study is to determine the clinical, morphological, and immunophenotypical presentation of 9 cases of a particular type of canine T-cell lymphoma/leukemia. The morphological presentation was a diffuse infiltration of small, medium-sized, or large blast cells with eccentric nuclei, hyperbasophilic cytoplasm, and a juxtanuclear, pale cytoplasmic area, giving a plasmacytoid appearance and suggesting a B-cell morphology. Surprisingly, all 9 cases were of T-cell phenotype (CD3+). Among the 7 immunophenotyped cases, 4 were CD4-/CD8+, 2 CD8+/CD4+, and 1 CD4+/CD8-. The median Ki-67 index was 65.7%, which placed this lymphoma in the high-grade group. This type of lymphoma/leukemia was found in dogs between 1 and 11 years of age, with a median age of 5.8. The male-female ratio was 0.8 for a reference population of 1.04. The most significant clinical findings were lymphadenopathy either generalized or localized in all cases, a mediastinal mass in 4 cases, bone marrow involvement in 7 cases, hypercalcemia in 4 cases, along with an aggressive clinical course and a poor response to chemotherapy in all cases, with a median disease-free survival time of 3 months.

Canine T-cell lymphomas: a morphological, immunological, and clinical study of 46 new cases.

The aim of this study is to report 46 new cases of canine T-cell lymphomas among a series of 140 lymphomas studied by immunophenotyping (incidence 32.8%). According to the updated Kiel classification adapted to the canine species, 13 were classified as low-grade and 33 as high-grade lymphomas. Among the low-grade lymphomas, five were small clear-cell lymphomas, three were pleomorphic small-cell lymphomas, and five mycosis fungoides. Among the high-grade cases, there were 11 pleomorphic mixed-, small-, and large-cell lymphomas, 6 pleomorphic large-cell lymphomas, 11 lymphoblastic lymphomas, and 5 unclassifiable high-grade plasmacytoid lymphomas. The cytohistologic features were highly suggestive of a T-cell phenotype on the basis of cell morphology (irregular nuclei and clear cytoplasms) (30/46 cases), a T-cell zone pattern, and the presence of hyperplastic postcapillary venules (22/46 cases). All 46 cases were CD3+ CD79a-, and among 34 cases investigated for CD4 and CD8 expression, 13 were CD4+CD8-, 13 were CD8+CD4-, and 8 were CD4CD8 double positive or double negative. The pleomorphic mixed lymphomas were mainly CD4+CD8- (6/7) and the lymphoblastic lymphomas were double positive or double negative (6/8). The main clinical, hematologic, and biochemical features were generalized (28/46) or regional lymphadenopathy (16/46), hepatosplenomegaly (15/46), extranodal involvement (11/46), mediastinal mass (9/46), and leukemia (8/46), which were mainly present in cases of lymphoblastic lymphomas and hypercalcemia (16/46).

Atypical forms of canine leishmaniosis.

Canine leishmaniosis is a common disease in the Mediterranean area, but sporadic cases in dogs having travelled through endemic regions are also reported. The disease's evolution is usually chronic and symptoms are either non-specific (fever, weight loss, lethargy, enlarged lymph nodes), dermatological, renal or ocular. The purpose of this article is to review the literature and to describe our own experience of certain atypical forms of canine leishmaniosis. These include specific skin lesions, monoclonal gammopathy, renal failure (without any other signs), chronic colitis, haemostatic problems and disorders of the cardiovascular, respiratory and musculo-skeletal systems.

Canine large granular lymphocyte leukemia and its derived cell line produce infectious retroviral particles.

We describe a case of large granular lymphocyte (LGL) leukemia in a dog that we followed over a period of 2 years. Analysis of a hematological profile revealed lymphocytosis (19,500 lymphocytes per microliter; reference values, 1,000-4,800 lymphocytes per microliter), with a majority of LGL on the blood smear. LGL is defined as a lymphoid subset comprising 10% of peripheral blood mononuclear cells and corresponding to either CD3- CD8- NK cells or CD3+ CD8+ T cells. The cells are characterized by abundant basophilic cytoplasm containing distinct granules of variable size and number. The characteristic phenotype of our leukemic LGL is of a cytotoxic T cell, CD3+ and CD8+. A new cell line, DLC 02, was established from the peripheral lymphocytes of the leukemic dog. Particles with type C retroviral morphology were found in ultrathin sections of DLC 02 cell pellets. These particles were found to have a sucrose gradient density of 1.17 g/liter and a reverse transcriptase activity with an Mn2+ preference, suggesting that they correspond to a mammalian type C oncovirus.

Clinical applications of flow cytometry and cell immunophenotyping to companion animals (dog and cat).

Clinical applications of flow cytometry to certain diseases of the dog and cat are now possible. The utility of such applications for diagnosis, prognosis and follow-up are illustrated here by a number of examples: feline AIDS resulting from FIV infection, Leukocyte Adhesion Deficiency in Irish setters, deep pyoderma in German shepherds, Immune-mediated Thrombocytopenia, canine Systemic Lupus Erythematosus and Leishmaniasis, Leukemia and Lymphoma.

Characterization of a canine long-term T cell line (DLC 01) established from a dog with Sézary syndrome and producing retroviral particles.

The canine DLC 01 cell line derives from a lymph node of a dog with Sézary syndrome. The DLC 01 cell phenotype is CD4-, CD8+, CD45+, DQ+, similar to that of original cells after treatment with dimethylsulfoxide or phorbol myristate. Canine cutaneous T cell lymphoma are usually CD4-, CD8+ in contrast to their human counterparts which are CD4+, CD8-. Therefore, the DLC 01 cell line appears to be a unique model to study the mechanism of all surface molecule expression in vitro. Viral particles with retrovirus type-C morphology were found in ultrathin sections of DLC 01 cell pellets. Retroviral particles are spontaneously produced after the 50th cell passage or after induction with 0.5% dimethylsulfoxide. This is the first description of a dog lymphoid cell line spontaneously growing and producing a retrovirus. It was found to share several features in common with feline and murine leukemia viruses.

Cytohistological and immunological classification of canine malignant lymphomas: comparison with human non-Hodgkin's lymphomas.

Non-Hodgkin's lymphomas (NHLs) in man are on the increase. They are also common in dogs, which, as close companions of man, may constitute a useful experimental model. However, comparisons cannot be made without a reliable morphological and immunological classification of canine NHL. Canine NHLs (n = 134) were classified on the basis of fine-needle lymph-node aspirates according to the Kiel classification, and 92 were re-classified according to the Working Formulation and the updated Kiel classification, in a histological and immunological study. The immunophenotype was determined (1) in 92 cases by the use of the pan-T anti-CD3 polyclonal antibody and the pan-B anti-mb1 monoclonal antibody on paraffin wax-embedded tissue sections, and (2) in 47 cases by the use of a panel of polyclonal and monoclonal antibodies on fresh preparations and frozen tissue. Cytological analysis showed a predominance of high-grade lymphomas (73.9%) over low-grade lymphomas (26.1%); it also demonstrated forms not reported in other species (small-cell variants, lymphomas with macronucleolated medium-sized cells [MMCs], and polymorphic lymphomas with a centroblastic component). Histological examination revealed the rarity of follicular lymphomas (2.2% of cases), an appearance suggestive of T-cell neoplasia (8.7% of cases), and evidence that some MMC lymphomas originated in the marginal perifollicular zones. Some (26%) of the lymphomas were of the T-cell phenotype: the majority of these consisted of small-cell, low-grade lymphomas and mycosis fungoides, the rest being either high-grade pleomorphic lymphomas (mixed or large-cell) or, rarely, high-grade, small noncleaved-cell, plasmacytoid lymphomas. No lymphoma expressed a double (T and B) phenotype. This study revealed similarities with, but also notable differences from, human NHL. In particular, the MMC lymphomas may constitute an interesting equivalent of human marginal zone B-cell lymphomas.

Growth fractions in canine non-Hodgkin's lymphomas as determined in situ by the expression of the Ki-67 antigen.

The proportion of proliferating cells in non-Hodgkin's lymphomas (NHLs) as determined in situ by the expression of the Ki-67 antigen, has prognostic value in human oncology, and is strongly related to the different grades of malignancy. The evaluation of the Ki-67 index in canine NHLs may be useful in assessing the individual variability of the growth fraction in the different sub-types of lymphoma, and also the validity of the classification in terms of grade of malignancy. The growth fraction was evaluated in 92 canine NHLs, previously classified according to the Kiel classification (as adapted to the canine species), by determining the expression of the Ki-67 antigen with the MIB1 antibody on (1) paraffin-wax tissue sections in all 92 cases, and (2) fine-needle aspirates or tumour imprints in 30 cases. The labelling appeared satisfactory in 88% of the cases, with good concordance between the histological and cytological data. A highly significant correlation (P < 0.001) was established between the proportion of Ki-67+ cells and the classification into low-grade (Ki-67 index < 21%) and high-grade malignancy (Ki-67 index > 21% and usually > 29%). In the low-grade lymphoma group, a macronucleolated medium-sized-cell lymphoma not found in man had the lowest proliferation index. In the high-grade malignancy group, the number of Ki-67+ cells seemed to be proportional to cell size, whatever the phenotype, with the rare exceptions of some unclassifiable small-cell Burkitt-type or plasmacytoid lymphomas, which were highly proliferating. The classification of lymphomas into low-grade and high-grade appears to correlate well with their proliferative index. The existence of individual variations, within given categories of canine NHL, suggests that, as in human medicine, prognosis may be assisted by determining the growth fraction at initial diagnosis, and by fine-needle aspiration at relapses.

Immunophenotype of the canine transmissible venereal tumour.

The canine transmissible venereal tumour is a naturally occurring contagious round-cell neoplasia which is primarily located in the mucous membrane of the external genitalia in dogs of either sex. In order to specify the controversial cytogenetic origin of this round-cell tumour, 14 cases of canine transmissible venereal tumour, formalin- or Bouin-fixed and paraffin-embedded, were subjected to extensive immunophenotypic analysis using reagents specific to a variety of cytoplasmic or surface antigens: lysozyme, ACM1 antigen, vimentin, neuron-specific enolase, glial fibrillary acidic protein, desmin, alpha smooth muscle actin, CD3, IgG, kappa and lambda light chains, and keratin. Lysozyme immunoreactivity was detected in all cases, ACM1 antigen in 11 of 14, neuron-specific enolase in 11 of 14, vimentin in 10 of 14, glial fibrillary acidic protein in 4 of 14 and desmin in 1 of 14. All the sections were negative to keratins, alpha smooth muscle actin and CD3, whereas in five cases, perivascular tumour cells contained Ig G, kappa and lambda light chains. The immunoreactivity to lysozyme and ACM1 antigen supports the hypothesis of a histiocytic immunophenotype for the canine transmissible venereal tumour.

Lymphocyte subset abnormalities in canine leishmaniasis.

Peripheral blood lymphocyte subpopulations were studied in 42 Leishmania infantum-infected dogs using flow cytometry. Twenty-two healthy dogs were used as a control group. Analysis of the B-cell populations showed a reduction in the number of CD21+ cells in all the infected dogs. On the other hand, the disease was found to be associated with a striking decrease in the number of CD21+ cells and of T-lymphocyte CD4+ cells in comparison with asymptomatic dogs and with healthy dogs. This study suggests that the dysimmunity which is observed with leishmaniasis may be linked to a reduced number of T-lymphocyte CD4+ cells.