Idiopathic immune-mediated hemolytic anemia: treatment outcome and prognostic factors in 149 dogs.

BACKGROUND: Canine idiopathic immune-mediated hemolytic anemia (IMHA) is associated with a high mortality, especially in the 1st 2 weeks after diagnosis despite treatment. OBJECTIVES: To determine treatment outcome and identify prognostic variables in order to define areas of future research. ANIMALS: One hundred forty-nine dogs with hematocrit <30% and either a positive Coombs' test or spherocytosis and with no evidence of disease that can trigger IMHA were included. METHODS: Retrospective cohort study. All dogs were treated with prednisolone and azathioprine according to a standard protocol. Survival analysis was performed by the Kaplan-Meier method. Variables recorded at the time of diagnosis were tested as possible prognostic variables in a univariate and multivariate Cox proportional hazard model. RESULTS: The main predictors for mortality in dogs with idiopathic IMHA are the presence of increased plasma urea concentration, bands, thrombocytopenia, and petechiae at the time of diagnosis. The estimated Kaplan-Meier half-year survival was 72.6% (95% confidence interval [CI]: 64.9-81.3%). Mortality occurred mostly within the 1st 2 weeks. Cox proportional hazards analysis indicated that increased plasma urea concentration, icterus, and petechiae were the major independent predictors of mortality in the 1st 2 weeks. In most dogs that survived IMHA, a 3-month protocol of azathioprine with prednisolone maintained clinical remission. The estimated half-year survival for dogs that survived the 1st 2 weeks was 92.5% (95% CI: 86-99.3%). CONCLUSIONS AND CLINICAL IMPORTANCE: If the dogs survived IMHA, a 3-month protocol of prednisolone and azathioprine was effective with regard to survival and clinical outcome. Future research should be directed at identifying whether thrombotic tendency in dogs with IMHA is the main contributor to the development of increased plasma urea concentration, icterus, thrombocytopenia, and petechiae.

Dog-DAT: a direct agglutination test using stabilized, freeze-dried antigen for the serodiagnosis of canine visceral leishmaniasis.

We have evaluated the use of an improved direct agglutination test (DAT) based on stable, freeze-dried antigen for the detection of anti-Leishmania antibodies in canine serum samples. With a cut-off value of 1:640, the sensitivity of the DAT was shown to be 100% and the specificity of the test was 98.8%.

The diagnostic significance of the direct antiglobulin test (DAT) in anemic dogs.

The direct antiglobulin test (DAT) was positivein 134 (36.1%) of 371 anemic dogs with internal diseases. Four principal types of reaction were recognized: IgG alone in 15 (11.2%), IgG + C' in 41 (30.6%), C' alone in 74 (55.2%) and IgM + C' in 2 (1.5%). Rarely, IgM and/or IgA reactions occurred in association with strong IgG + C' reactions. In 2 (1.5%) DAT-positive dogs the type of reaction was not clear. One or more symptoms of hemolysis, such as hemoglobinemia, indirect type hyperbilirubinemia, increased red cell osmotic fragility, and increased fecal urobilinogen excretion, were demonstrated in 84 DAT-positive dogs. These consisted of 10 of 15 dogs with IgG type DAT, 36 of 41 dogs with IgG + C' type DAT, 36 of 74 dogs with C' type DAT and 2 of 2 dogs with IgM + C' type DAT. Most dogs with IgG + C' type reactions had severe hemolysis, whereas "primary" or "associated" diseases were recognized in only 26 of 56 cases. IgG type incomplete warm antibody, reacting with pooled donor cells, was demonstrated in red cell eluates in each of 3 dogs with IgG type DAT and in 6 of 7 dogs with IgG + C' type reactions. This indicates that dogs with IgG or IgG + C' reactions usually have autoimmune hemolytic anemia. In dogs with C' type DAT, indications of hemolysis were frequently minimal or absent. Symptoms almost always indicated some "primary" disorder. Diagnoses mainly included infections, inflammatory and neoplastic (especially myelo- and lymphoproliferative)diseases. In only 7 (9.5%) of 74 dogs with C' type DAT no diagnosis other than (transient peracute) hemolytic anemia was made. The results of tests for antibodies in the serum and red cell eluates were always negative in dogs with C' type DAT. In one dog with hemolytic anemia and C' + IgM type DAT, there was a high titer of IgM cold agglutinins in the serum and in heat eluates. It is concluded that a positive DAT with anti-IgG antiserum is a strong indication of autoimmune hemolytic anemia but that a reaction of the C' alone type is a rather common phenomenon in canine internal diseases which is seldom associated with serious hemolysis.

An enzyme-linked immunosorbent assay (ELISA) for von Willebrand factor antigen (vWf-Ag) in canine plasma.

A quantitative enzyme-linked immunosorbent assay (ELISA) has been developed to measure canine von Willebrand factor antigen (vWf-Ag) in plasma of the dog. A vWf-Ag antiserum was raised in rabbits and purified by preabsorption with the low molecular weight vWf-Ag-deficient fraction of canine cryoprecipitate, followed by affinity chromatography on protein-A Sepharose. The rabbit anticanine vWf-Ag IgG was used to bind the vWf-Ag of the test plasmas to the solid phase and to prepare the enzyme-antibody conjugate in ELISA. Normal rat serum was used as blocking agent. The standard curve was linear (r2 greater than 0.98) and reproducible after logit-log transformation. The interassay coefficient of variation (CV) in test plasmas with various vWf-Ag concentrations was never greater than 7.7%. Assayed values in dilutions of pooled normal canine plasma added to canine vWf-Ag-deficient plasma were linear between 0 and 100% (r2 = 0.99) and indicated excellent analytical recovery of vWf-Ag. In 18 dogs with various internal diseases, including von Willebrand's disease and haemophilia A, the coefficient of correlation between the results of the ELISA and those of electroimmunodiffusion (EID) was 0.93.

Effect of sodium heparin and antithrombin III concentration on activated partial thromboplastin time in the dog.

Regulation of blood coagulation was studied in 12 dogs, using subcutaneous administration of sodium heparin. Dosage of heparin needed to achieve the desired 1.5- to 2.5-fold increase in the activated partial thromboplastin time (APTT) was 250 to 500 IU/kg of body weight. Increased APTT lasted less than 6 hours. Repeated heparin administration, using the lowest dosage (250 IU/kg) every 6 hours, induced an unacceptable prolongation of clotting times during the first 2 days of treatment. Prolonged administration at a dosage of 200 IU/kg every 6 hours adequately maintained the desired hypocoagulative state initially; after 2 days, however, the prolonged APTT steadily decreased. The decreasing effect was proportionate to a decrease in plasma antithrombin III (AT III). To sustain a correctly balanced hypocoagulative state from prolonged subcutaneous administration of heparin, APTT values should be determined regularly to monitor therapy. In addition, transfusion of AT III-rich donor plasma may be necessary when low plasma AT III reduces the effects of heparin.

Disseminated intravascular coagulation.

Etiology, pathogenesis, clinical features, laboratory findings, and therapy of disseminated intravascular coagulation (DIC) in the dog and the cat are reviewed.

Canine leishmaniasis. A review based on 95 cases in The Netherlands.

The clinically relevant aspects of canine leishmaniasis are reviewed. Included are data from 92 dogs imported from the Mediterranean basin and at least 2 autochthonous cases. New aspects on pathogenesis are presented, including evidence that canine leishmaniasis is an immune complex disease. Therapy with meglumine antimonate (Glucantime) is evaluated. The hazards of imported canine leishmaniasis for public health are discussed.

Bleeding tendency as a cause of epistaxis in the dog.

Based upon a survey of the pathophysiology of haemostasis, the causes of epistaxis in the dog are discussed, and guidelines for a diagnostic and therapeutic approach are given.

Transient juvenile hypoglycaemia in a Yorkshire terrier and in a Chihuahua.

Two cases of transient juvenile hypoglycaemia in the dog are reported. The symptoms, diagnosis and treatment are described and pathogenesis and differential diagnosis discussed.

The effect of intravenous or subcutaneous administration of meglumine antimonate (Glucantime) in dogs with leishmaniasis. A randomized clinical trial.

The efficacy of i.v. versus s.c. administration of Glucantime (100 mg/kg of body weight/day) was studied in 41 dogs with leishmaniasis without serious renal insufficiency. Remission was obtained in 35 dogs (85.4%) after 3 to 6 weeks of treatment but there was a relapse within 1 year in 26 dogs (74.3%). The median period of remission was 6 months. Cross-over therapy resulted in remission in 17 of 20 dogs. The percentage of remission after initial and cross-over therapy, the median relapse free period, and survival did not differ significantly between the two groups. There were very few complications and most were of minor clinical importance. Thrombophlebitis developed in one dog after i.v. injection. In dogs with leishmaniasis without serious renal insufficiency, there is a 75% probability of survival for more than 4 years following treatment with Glucantime for 3 to 6 weeks, with additional treatment when relapses occur.

Trypanosomiasis in a dog imported in The Netherlands.

A case-report is presented of a Trypanosoma evansi infection in a dog imported from Nepal. The clinical symptoms included fever, anorexia, and weight loss. Diagnosis was made through morphologic study of blood smears from the patient.

A case of autochthonous canine leishmaniasis in The Netherlands.

The transmission of visceral leishmaniasis (VL) in the absence of its natural vector, the sandfly, is considered exceptional. This report describes VL in a 12-month-old dog which had never been in an area in which VL is endemic but was born in the Netherlands from a bitch that had been infected in Spain. Although the mode of transmission, via the placenta or otherwise, is unknown, it can be concluded that bitches with VL can be a source of infection for their pups, even in a sandfly-free non-endemic area. The dog was successfully treated with allopurinol.

Type III von Willebrand's disease in Dutch kooiker dogs.

Type III von Willebrand's disease (vWD) was diagnosed in 38 Dutch kooiker dogs. Ten male and 9 female probands had been referred independently of each other to the Utrecht University Clinic for Companion Animals because of a moderate to severe bleeding tendency. Screening of 717 Dutch kooiker dogs, including 356 puppies, detected vWD in another 19 dogs. Diagnosis was based on non-detectable amounts (< 1.6%) of von Willebrand factor antigen (vWF:Ag) in plasma by ELISA. Capillary bleeding time (CBT) was prolonged (> 10 min) and polybrene cofactor activity (vWF:PbCo) was not detectable in 11 dogs tested. No distinguishable protein bands were detected by multimer analysis. As in Scottish terriers with type III vWD, factor VIII clotting activity (FVIII:C) in affected Dutch kooiker dogs was decreased but considerably less than in humans with type III vWD. A recessive mode of inheritance was indicated by the normal or subnormal but measurable amounts of vWF:Ag in the plasma of eight pairs of parents of affected dogs. The F1 offspring resulting from the experimental mating of two affected dogs consisted of three affected males and four affected females. In 39 obligatory carriers vWF:Ag ranged from 30% to 114% with median and mean vWF values of 64% and 64.2%, respectively, and was subnormal (< 50%) in only 9 animals.

Polycythaemia vera in a dog treated by repeated phlebotomies.

Polycythaemia vera (PV) was diagnosed in a dog by demonstration of an increased red cell mass in association with normal arterial oxygen saturation and the absence of conditions known to be associated with secondary polycythaemia. The dog was treated exclusively by repeated phlebotomies and replacement of the removed volume by colloid and crystalloid solutions. It survived for one year and was generally free of signs.

Familial stomatocytosis--hypertrophic gastritis (FSHG), a newly recognised disease in the dog (Drentse patrijshond).

A newly recognised disease, which we have given the provisional name of familial stomatocytosis-hypertrophic gastritis (FSHG), is described in two families of dogs of the Drentse partrijshond breed. The affected dogs consisted of 3 females and 5 males, 3 to 19 (mean 9.5) months of age at admission. The main clinical problems were diarrhoea, icterus, and ataxia and paresis of the pelvic limbs. Laboratory evaluation revealed abnormal red cell shape (stomatocytosis), increased osmotic fragility, haemolytic anaemia, and increased liver enzymes and serum bilirubin. Gastroscopic and histopathologic examination of the gastric mucosa revealed hypertrophic gastritis resembling Ménétrier's disease in man. Histologic findings in the liver were suggestive of progressive liver disease. Cysts were found in the kidneys of the five oldest patients. Electroneurography in 2 dogs revealed polyneuropathy. In the parents of 2 patients (sister and brother), there were no clinical or laboratory abnormalities. An autosomal recessive hereditary defect of lipid metabolism is suspected.

Evaluation of the potential causes of epistaxis in dogs with natural visceral leishmaniasis.

Haemostasis was evaluated in 19 dogs with natural Leishmania infection, six of them with a history of epistaxis, and the results were compared with the results from 24 healthy dogs. In addition, the dogs' blood pressure was measured and biopsies were taken from the nasal mucosa. Buccal mucosa bleeding time was prolonged in the dogs with leishmaniasis (P < 0.002) and most significantly in those with epistaxis (P < 0.005). None of the Leishmania-infected dogs had thrombocytopenia, low levels of plasma von Willebrand factor antigen, a prolonged prothrombin time or activated partial thromboplastin time, a low plasma fibrinogen concentration or high serum fibrin degradation products. These results rule out defects of secondary haemostasis or disseminated intravascular coagulation as significant causes of epistaxis in non-complicated leishmaniasis. Histopathology of the nasal mucosa of 10 of the affected dogs, three of them with epistaxis, revealed ulcerative and inflammatory lesions in all of them.

Risk of infection with Leishmania spp. in the canine population in the Netherlands.

The dog is the main reservoir of Leishmania infantum, the causative agent of visceral leishmaniasis (VL) in humans in Southern Europe. In order to identify the risk of dogs from a Leishmania non-endemic area traveling to a Leishmania-endemic area becoming infected and the risk of transmitting infection to humans in non-endemic areas an investigation was performed, in which the results of a questionnaire were combined with the results of a serologic survey. The questionnaire was sent to 1478 at random chosen families in the Netherlands. Of the 59.0% responders 28.0% had one or more dogs and 4.8% of these dogs had visited Southern Europe during the summer period of that year. On a total population of 1,200,000 dogs in the Netherlands, this means that each year some 58,000 dogs are at risk of being exposed to a Leishmania infection in Southern Europe. During the period 1990-1992 blood was collected for serology in 1911 dogs presented to the Utrecht University Clinic because of clinical problems not related to leishmaniasis, of which 434 had been in Southern Europe in the foregoing years. None was serologically positive. From these data it can be deduced that the highest chance to obtain leishmaniasis during a vacation in Southern Europe is mathematically less than 1/434 or less than 0.23%. Serology was also performed during the period 1989-1993 in 597 dogs that had been in Southern Europe and were suspected of leishmaniasis. Titers were positive in 145 of these samples. Sixty-four of these dogs were born in the Mediterranean and had been imported into the Netherlands. Excluding these imported dogs, it was calculated that at least 0.027% of the 58,000 dogs yearly taken to Southern Europe during holidays become infected with Leishmania. In order to establish the risk of disease transmission for people in close contact with an infected dog, serum samples of owners and house mates of 37 dogs with leishmaniasis were tested. All 112 sera tested negative. It was concluded that the risk to get leishmaniasis was between 0.027% and 0.23% for the dog when taken to Southern Europe during vacation, and that the risk for owners in non-endemic areas to get leishmaniasis from an infected dog is minimal.

Haemophagocytic syndrome with disseminated intravascular coagulation in a dog.

Clinical signs and haematological abnormalities of haemophagocytic syndrome of unknown origin are described for a male, nine-year-old rottweiler referred because of weakness, depression, mild weight loss and relapsing fever. Mucous membranes were pale and the spleen was enlarged. Ultrasonography revealed diffuse irregular structures in the enlarged spleen, and cytological examination of multiple fine needle aspirates of the spleen demonstrated extramedullary haematopoiesis. Haematological examination revealed pancytopenia and disseminated intravascular coagulation. A bone marrow smear contained numerous marrow macrophages with a cytologically benign appearance, containing phagocytosed haematopoietic cells. The dog died one week after referral. The differential diagnosis is discussed.

Hemophilia A and hemophilia B in a family of French bulldogs.

A congenital coagulation defect was suspected in 10 male French bulldogs, independently referred to the Small Animal Clinic of the Utrecht State University by private pet owners from all over the country. The cases are described in this report. Coagulation studies, performed in 8 of these dogs, revealed a factor VIII (anti-hemophilic globulin) deficiency in 5, and a factor IX (Christmas factor) deficiency in 3 propositi. A pedigree analysis revealed that all of the 10 propositi were lineal descendants, in the female line, of one and the same female ancestor. An inquiry by letter among the owners of 210 male descendants, in the female line, of this common ancestor revealed hemorrhagic episodes in at least another 10 male offspirng. The presence of a large number of carriers can be expected among the French bulldog population in the Netherlands, since the officially registered female offspring in the female line of the ancestor bitch, comprised over 170 dogs as of January, 1971. The possible mechanisms responsible for the simultaneous occurrence of hemophilia A and B in one canine family are discussed.

[Transient juvenile hypoglycemia in puppies]. / Passagère juveniele hypoglycaemie bij pups.

Two cases of transient juvenile hypoglycaemia are reported. The symptoms, diagnosis and treatment are described, and the pathogenesis and differential diagnosis are discussed.