Mathios E. Mylonakis

Chronic Canine Ehrlichiosis (Ehrlichia canis): A Retrospective Study of 19 Natural Cases

Nineteen dogs from Greece with chronic ehrlichiosis were studied. The dogs exhibited bicytopenia or pancytopenia, bone marrow hypoplasia, seroreactivity to Ehrlichia canis (E. canis) antigens, and had no history of drug or radiation exposure. Anorexia, depression, severe bleeding tendencies, hypoalbuminemia, and increased serum alanine aminotransferase activity were also hallmarks of the disease. All these animals eventually died, irrespective of the treatment applied. Some dogs were also serologically positive for Rickettsia conorii, Leishmania infantum (L. infantum), and Bartonella vinsonii subspp. berkhoffii. Polymerase chain reaction testing of bone marrow samples revealed E. canis, Anaplasma phagocytophilia, Anaplasma platys, and L. infantum in some dogs. Concurrent infections did not appear to substantially influence the clinical course and final outcome of the chronic canine ehrlichiosis.

A cross-sectional study of Leishmania spp. infection in clinically healthy dogs with polymerase chain reaction and serology in Greece.

A total of 73 clinically healthy hunting dogs, experiencing an outdoor lifestyle and originating from an area where canine leishmaniasis is endemic, were included in the study. Polymerase chain reaction (PCR) and indirect immunofluorescent antibody test (IFAT) for Leishmania spp. were done on bone marrow and serum samples, respectively, obtained from all 73 dogs, just before the beginning of the sandfly season. PCR was found positive in 46/73 (63%) whereas, IFAT only in 9/73 (12.3%) of the dogs. The prevalence and the incidence of Leishmania infection by PCR were 61.9 and 47.1%, respectively. No association was found between the breed, age, sex, length of hair coat of the dog, urban or rural life and the presence of ample vegetation and water collections in the proximity of their living quarters, and the result of PCR. These findings clearly demonstrate that most of the dogs residing areas where leishmaniasis is endemic become infected but usually remain seronegative. Serological screening of the general canine population in these areas may result in an underestimation of the true prevalence of the infection rate.

A randomised, blinded, placebo-controlled clinical trial with allopurinol in canine leishmaniosis.

A total of 45 non-uremic dogs, with clinical signs indicating leishmaniosis, entered the study. Diagnosis was confirmed by indirect immunofluorescence assay (IFA) on serum and polymerase chain reaction (PCR) on bone marrow samples. The dogs were randomly allocated into Group A (n=37) that received allopurinol (10mg/kg B.W., per os, twice daily) for 4 consecutive months, and Group B (n=8) that were placebo-treated. Clinical signs were scored just before and at monthly intervals throughout the study period, in a blinded and independent fashion. Complete blood count, serum biochemistry profile, urinalysis, lymph node and bone marrow parasitology, IFA and enzyme-linked immunosorbent assay (ELISA) serology and bone marrow PCR were carried out at the beginning and at the end of the trial. A total of three Group A and one Group B dogs died of end stage kidney disease that developed during the trial. In Group A animals that endured the trial there was a significant improvement in the general body condition, conjunctivitis, peripheral lymphadenopathy, splenomegaly, masticatory muscle atrophy, ulcerative stomatitis, epistaxis, exfoliative dermatitis, cutaneous ulcerations, blepharitis and nasodigital hyperkeratosis. The same observation was made for anemia, lymphopenia, hyperproteinemia, hyperglobulinemia, hyperphosphatemia, increased alkaline phosphatase activity and the low albumin/globulin ratio. By contrast, no improvement of any kind was seen in Group B dogs. Lymph node and bone marrow parasite numbers were significantly decreased in Group A animals. In Group B, that occurred only in the lymph nodes. Apart from remission of clinical signs and restoration to normal of clinicopathological abnormalities, allopurinol did not eliminate Leishmania organisms, as the PCR result on bone marrow was still positive in all the dogs that finished the trial.

Evaluation of cytology in the diagnosis of acute canine monocytic ehrlichiosis (Ehrlichia canis): a comparison between five methods

The purpose of this study was the comparison of the diagnostic sensitivity between buffy coat (BC), peripheral blood (PB), lymph node (LN), bone marrow (BM) and short-term culture (P-D) cytology that has been based on the detection of Ehrlichia canis morulae, in the acute phase of canine monocytic ehrlichiosis (CME). Their cellular localization, total numbers and microscopic differentials were also investigated. The highest sensitivities were achieved after evaluating 1000 oil immersion fields (OIFs) in BC (66%) and an equal number in LN (60.9%) smears, separately or together (74%). The morulae were more often detected into lymphocytes than monocytes. The highest total number of morulae (n=143) were found in P-D smears. Finally, to avoid false positive diagnoses, platelets, lymphocytic azurophilic granules, lymphoglandular bodies and phagocytosed nuclear material should not be confused with the morulae.

Molecular Documentation of Bartonella Infection in Dogs in Greece and Italy

ABSTRACT This study reports the occurrence of “Bartonella rochalimae” in Europe and the presence of Bartonella vinsonii subsp. berkhoffii genotypes II and III in dogs in southern Italy and provides DNA sequencing evidence of a potentially new Bartonella sp. infecting dogs in Greece and Italy.

Factors associated with the occurrence of epistaxis in natural canine leishmaniasis (Leishmania infantum)

BACKGROUND Canine leishmaniasis (CanL) is a common cause of epistaxis in dogs residing in endemic areas. The pathogenesis of CanL-associated epistaxis has not been fully explored because of the limited number of cases reported so far. HYPOTHESIS Epistaxis in CanL could be attributed to more than 1 pathomechanism such as hemostatic dysfunction, biochemical abnormalities, chronic rhinitis, and coinfections occurring in various combinations. ANIMALS Fifty-one dogs with natural CanL. METHODS The allocation of 51 dogs in this cross-sectional study was based on the presence (n = 24) or absence (n = 27) of epistaxis. The potential associations among epistaxis and concurrent infections (Ehrlichia canis, Bartonella spp., and Aspergillus spp.), biochemical and hemostatic abnormalities, and nasal histopathology were investigated. RESULTS Hypergammaglobulinemia (P= .044), increased serum viscosity (P= .038), decreased platelet aggregation response to collagen (P= .042), and nasal mucosa ulceration (P= .039) were more common in the dogs with epistaxis than in those without epistaxis. The other significant differences between the 2 groups involved total serum protein (P= .029) and gamma-globulin (P= .013) concentrations, which were higher, and the percentage platelet aggregation to collagen, which was lower (P= .012) in the epistaxis dogs. CLINICAL IMPORTANCE CanL-associated epistaxis appears to be the result of multiple and variable pathogenetic factors such as thrombocytopathy, hyperglobulinemia-induced serum hyperviscosity, and nasal mucosa ulceration.

Factors affecting the occurrence, duration of hospitalization and final outcome in canine parvovirus infection

The objectives of this matched case-control study in a veterinary teaching hospital were to investigate the influence of signalment and historical data on the odds of occurrence of canine parvovirus (CPV) enteritis and the potential usefulness of the clinical signs and clinicopathologic abnormalities recorded on admission as prognostic indicators of mean duration of hospitalization (DOH) and outcome of the disease. Ninety-four puppies with natural CPV enteritis and 188 age-matched controls were studied. The odds to develop CPV enteritis were higher in purebreds compared to mixed-breed puppies. Vomiting and depression at the time of admission were associated with a prolongation of DOH by 2 and 1.75 days, respectively. The lymphopenic and hypoalbuminemic dogs were hospitalized for 1.9 and 2.5 more days, respectively, compared to those without these abnormalities. The odds of non-survival were higher in those puppies with evidence of systemic inflammatory response syndrome (SIRS) at the time of admission.

Serum acute phase proteins as clinical phase indicators and outcome predictors in naturally occurring canine monocytic ehrlichiosis.

BACKGROUND Canine monocytic ehrlichiosis (CME), caused by Ehrlichia canis, is an important tick-borne disease of global importance. Currently, limited information is available on the diagnostic and prognostic value of acute phase proteins (APPs) in dogs naturally infected with E. canis. HYPOTHESIS APPs may be useful indicators of the clinical phase of CME and predictive of the clinical outcome (death or survival). ANIMALS Fifty-six dogs naturally infected with E. canis and 7 clinically healthy control dogs. METHODS C-reactive protein (CRP), serum amyloid A (SAA), haptoglobin (Hp), and albumin concentrations determined on admission were retrospectively compared among 27 dogs with nonmyelosuppressive CME, 29 dogs with myelosuppressive CME and 7 healthy dogs. Diagnosis of CME was based on clinical and clinicopathological findings, seropositivity to E. canis, polymerase chain reaction amplification of E. canis-specific 16S rDNA, microscopic observation of Ehrlichia sp. morulae in blood monocytes or some combination of these. RESULTS Mean concentrations of CRP, SAA, and Hp were significantly higher in the myelosuppressed dogs compared with the other groups, but no significant differences were found in the concentration of albumin. Survival analysis of the affected animals indicated that APP concentrations were not associated with clinical outcome; the latter was strongly associated with pancytopenia (odds ratio for death 22.7) and neutropenia (odds ratio for death 7.7). CONCLUSIONS AND CLINICAL IMPORTANCE CRP, SAA, and Hp serum concentrations on admission are useful indicators of the clinical phase of CME, but are not useful predictors of clinical outcome.

Cytological and molecular detection of Leishmania infantum in different tissues of clinically normal and sick cats

Natural infection of domestic cats by Leishmania infantum (synonym: L. chagasi) has been demonstrated in several European, Latin American, and Asian countries, and the estimated prevalence of infection, based mainly on blood PCR, ranges from 0.3% up to 60.6%. In this study we aimed to: (a) estimate the prevalence of the infection by L. infantum in clinically normal cats (group A; n=50) and in cats with various clinical signs (group B; n=50), living in an endemic region, by both cytological examination of four different tissues (lymph node, skin, bone marrow, and conjunctiva) and by PCR in four different tissues (blood, skin biopsies, bone marrow, and conjunctiva); (b) compare the diagnostic sensitivity of the above methods and evaluate for possible associations between their results; and (c) investigate the possible associations between infection by L. infantum and signalment, living conditions, season of sampling, and health status of the cats. The prevalence of the infection in the study population was 41% and did not differ (P=0.839) between group A (42%) and B (40%) cats. Lymph node, skin, bone marrow and conjunctiva cytology was always negative. Therefore, the diagnosis of the infection was based only on PCR in blood, skin biopsy, bone marrow and conjunctiva, which was positive in 13%, 18.2%, 16% and 3.1% of the cats, respectively. PCR was positive in only one of the four tissues in 80.5% of the infected cats. The results differed (P=0.014) among the four tissues and were less frequently positive in conjunctiva compared to skin biopsies and bone marrow (P=0.007 for both comparisons), thus highlighting the need for multiple tissue PCR testing in order to minimize false-negative results. More PCR-positive cats were found when sampling was performed during the period of sandfly activity (odds ratio: 2.44; P=0.022). Also, in group B cats, the likelihood of PCR-positivity was higher (odds ratio: 3.93; P=0.042) among those presenting at least one systemic clinical sign that had been previously reported in cats with leishmaniosis.

A comparison of the prevalence of Spirocerca lupi in three groups of dogs with different life and hunting styles

The prevalence of Spirocerca lupi in 260 privately owned dogs with different life and hunting styles in Greece was based on the examination of randomly taken faecal samples using Telemans sedimentation technique. The dogs did not demonstrate any clinical signs of spirocerciasis. Although the prevalence was 10%, it was found to be significantly higher in trace hunting dogs (21%), than in scent hunting dogs (5%) and household pets (0%). There was no relationship between prevalence and age/sex of dogs. The impact of life and hunting styles on the prevalence of S. lupi in the dog and that of the faecal examination technique, are discussed.