Autoimmune haemolytic anaemia in dogs

The clinical, haematological and immunological findings in 24 dogs with Coombs' positive haemolytic anaemia are described; 33% were Old English Sheepdogs. Dogs with intravascular haemolysis had a shorter history of illnesses, more severe clinical signs including vomiting, jaundice and fever, and had a poor survival rate compared to dogs with extravascular haemolysis. The anaemia was severe and regenerative in 18 dogs, and was characterised by spherocytosis and microscopic red cell agglutination, with leukocytosis. Serum IgG levels were elevated in 20 dogs, and changes in IgM, IgA, C3 and C4 were found. Antinuclear antibody was also demonstrated in 13 dogs, of which 7 were Old English Sheepdogs. It is suggested that a distinct multisystem autoimmune syndrome exists within the local Old English Sheepdog population.     

Intussusception following renal transplantation in dogs (author's transl)]

In a consecutive and non-selected study of 54 kidney transplanted dogs, 12 cases of intussusception of the small intestine developed in 8 dogs. The patogenesis is still unknown. It has been postulated that the time of the operation (4--7 hours) and the segmental termination of the post-operative atony in the intestine are essential factors in this fatal complication. The last 16 dogs in this material were peroperatively treated with antikolinergics (Mestinon NFN), which was continued until normal function of the intestine. In these dogs there were no evidence of intussusception. The value of this profylaxis is open to discussion and it is essential to solve the problem of intussusception through a "blind" and controlled trial.     

Idiopathic auto-immune haemolytic anaemia in a horse

Extract

Sir:- In May 1982, an outbreak of severe lameness occurred among mature stags and hinds in a herd of red deer (Cervus elaphus) on a newly-established deer farm near Taupo. No other farm animals were present, the property having been destocked some months before arrival of the deer from several other North Island localities. When the matter was first referred to the local veterinary practitioner, up to 60 animals of the herd of 700 were affected. Males predominated. Most cases had a raw open lesion of the skin in the anterior region of the interdigital cleft with varying degrees of superticial epidermal necrosis as well as some progressive inflammation and ulceration. Destruction of subepithelial tissue was evident in the more advanced cases. In some instances, a deep putrefactive inflammation of the digital connective tissue extended into the phalangeal joints which had become gangrenous. Both front and rear feet were involved, but the horny area of the hoof was intact.     

Antigen specificity in canine autoimmune haemolytic anaemia.

Autoimmune haemolytic anaemia (AIHA) is the most common clinical manifestation of autoimmunity in the dog and generally presents as a profound, regenerative, Coombs' positive anaemia of acute or chronic onset. The disease pathogenesis involves formation of erythrocyte-specific autoantibodies of the IgG and IgM class that may fix complement resulting in intra- or extravascular haemolysis. Western blotting and immunoprecipitation studies using autoantibody eluted from the erythrocytes of dogs with AIHA have demonstrated specificity for erythrocyte glycophorins and the membrane anion-exchange molecule (band 3). Autoantibodies specific for the cytoskeletal molecule spectrin have been identified in serum by ELISA. The specificity of autoreactive T-cells has been examined in vitro using bulk cultures stimulated with a panel of autoantigens including intact erythrocyte membranes, purified glycophorin and spectrin fractions and a panel of overlapping 15-mer glycophorin peptides. Control responses to ConA and recall (vaccine antigens) and non-recall (KLH) antigens were measured in the same system. PBMC obtained from dogs that had recovered from AIHA consistently proliferated in response to erythrocyte membranes, with occasional responses to spectrin or glycophorin. PBMC from sone clinically normal dogs also responded to erythrocyte membranes. PBMC obtained from dogs closely related to AIHA cases gave the most consistent responses, including proliferation when stimulated by the glycophorin peptides. These data suggest that normal dogs harbour erythrocyte autoreactive lymphocytes, and that these cells may be primed in dogs recovered from AIHA or having genetic susceptibility to the disease.     

Parathion poisoning in cattle (author's transl)]

In a herd of dairy cattle half of the cows showed symptoms of acute poisoning. Blood- and hair samples were taken from seven of the cows, of which two did not show any clinical symptoms. The cholinesterase activities were in all the blood samples decreased to about 10 per cent of normal and parathion was found in all hair samples. The cholinesterase activities rose gradually during a 31/2 month period to the lower part of the normal range. Parathion was found in samples from the inner walls of the cowstable, and it was concluded that the poisoning was probably due to parathion spraying in the stable, while a suspicion of winddrift as a source of poisoning was rejected as less probable.     

Actinobacillus infections in swine (author's transl)]

Actinobacilli infections in pigs are relatively rare. Most cases were septicaemic in the first week of life. With increasing age manifestations after generalized infections were characteristic, such as arthritis, polyarthritis, endocarditis, nephritis, osteomyelitis and embolic pneumonia. Of 34 porcine strains 33 were identified as A. equuli and only one was identical with A. suis. The justification of retaining this species is discussed.     

Immune-mediated haemolytic anaemia in 110 dogs in Victoria, Australia

Objective   Evaluate the survival and prognostic indicators (i.e. breed predilection, season, blood transfusion, and the prevalence of autoagglutination) of dogs with immune-mediated haemolytic anaemia (IMHA) in Victoria, Australia.
Design   Retrospective study of 110 diagnosed with primary IMHA at the University of Melbourne Veterinary Clinic and Hospital.
Results   In total, 80 of the dogs (72.7%) were discharged from hospital and 48 of 65 (73.8%) dogs available for follow-up were known to be alive at 1 year, giving an overall 1-year survival of 48 (50.5%) of 95 dogs for which survival data were available. Regarding breed, 80 (18.2%) of the 110 dogs were Maltese-breed dogs compared with 81 (7.4%) of 1100 control dogs (P < 0.001). Springer Spaniels (P = 0.02), Hungarian Vizslas (P = 0.02) and Airedale Terriers (P < 0.001) were also over-represented compared with the control sample. There was no evidence of an association between the occurrence of IMHA in dogs and season in this study. Receiving one or more blood transfusions did not affect survival to the time of discharge from hospital. On initial blood smear examination, 57 (51.8%) of the 110 dogs had spontaneous autoagglutination and its presence was associated with decreased survival to discharge from hospital (P = 0.03). Packed cell volume, white cell count, platelet count and serum total bilirubin on admission had no effect on survival to the time of discharge from hospital or 1 year later.
Conclusion   Dogs with IMHA have a guarded prognosis as only half are still alive 1 year after the acute event.     

Concurrent immune-mediated haemolytic anaemia and severe thrombocytopenia in 21 dogs

The medical records of 21 dogs with concurrent immune-mediated haemolytic anaemia (imha) and severe thrombocytopenia (defined as an automated platelet count of less than 50x10(9)/l, confirmed by the examination of a blood smear) were reviewed. Their mean (sd) age was 5.8 (2.5) years. When compared with the 24,759 dogs in the hospital population for the same period Airedale terriers and dobermanns appeared to be over-represented with odds ratios of 22.5 (95 per cent confidence interval [ci] 5.2 to 97.9) and 7.6 (95 per cent ci 1.8 to 32.7) respectively. The median duration of the dogs' clinical signs was seven days, with a range from one to 17 days. Eleven of the dogs had a history of a tendency to bleed, and 15 had evidence of bleeding when examined. Twenty of the 21 dogs had been treated with glucocorticoids, nine with vincristine, and seven with azathioprine. Their median stay in hospital was four days, with a range from one to 17 days. The median period for which they survived after admission to hospital was five days, with a range from one to 558 days, and 16 of the 21 dogs had died or been euthanased within 30 days of their admission.     

Pesticide residues in feed-stuffs in Sweden (author's transl)]

The occurrence of pesticide residues was studied in samples of feed-stuffs produced in Sweden or imported to Sweden during the years 1972--1976. In all, 278 samples representing 37 types of feed-stuffs (components, as well as finished feeds) and 18 countries were analyzed. Residues of chlorinated hydrocarbon pesticides and PCBs were looked for in 224 samples, mostly feed components. The analytical method used involved solvent extraction, florisil-column clean-up, thinlayer chromatographic separation and gas-chromatographic determination. Chlorinated hydrocarbons were found in several samples. DDT and its transformation products were detected in 66 samples (29.5%), lindane in 44 (19.5%), PCBs in 25 (11.2%), alpha-BHC in 22 (9.8%), beta-BHC in 11 (4.9%) and dieldrin in 9 (4.0%). The levels were usually low (Table I). The chloropesticides occurred most frequently and at the highest levels in feed-stuffs of animal origin and in imported oil-feeds. In 25 of the samples the contents of sigmaDDT exceeded the maximum limit accepted by the National (Swedish) Food Administration for grain and bran intended for human consumption (0.05 mg/kg, Talbe IV). The highest residue level of sigmaDDT (0.66 mg/kg) was encountered in a sample of fish meal. The PCB levels found did not exceed the temporary tolerance established by FDA (1973) for finished animal feeds (0.2 mg/kg). One hundred and seven samples were analyzed for phenoxy acid residues using a thin-layer chromatographic and gas-chromatographic technique. Phenoxy acids were detected in only 2 of 62 randomly selected feed samples (0.05 and 0.2 mg/kg, respectively). The residue limit established by the National Food Administration for 2,4-D and MCPA in grain and bran intended for human consumption is 0.1 mg/kg. Fortyfour samples of feeds were submitted because of suspected phenoxy acid contamination. In 12 of the samples phenoxy acid residues were found. The highest level (3.5 mg/kg, MCPA) was observed in a sample of accidentally contaminated molasses. Considering the apparently low level of contamination of Swedish grain with chloropesticides, PCBs and phenoxy acids and the dilution on compounding feed-stuffs of animal origin and oil-feeds, only very low pesticide residue levels can be expected in Swedish finished animal feeds.     

Serum cardiac troponin I in dogs with primary immune-mediated haemolytic anaemia

Objectives : The assessment of serum cardiac troponin I concentrations in dogs with a range of nonprimary cardiac illnesses has revealed that cardiac myocyte damage is commonplace in many canine diseases. Whilst it is well established that dogs with fatal immune‐mediated haemolytic anaemia frequently have cardiac pathology based on post‐mortem examinations, there is limited information on the incidence of cardiac myocyte damage in this population of dogs. Methods : Serum cardiac troponin I concentrations were measured in 11 healthy dogs, 27 dogs with primary haemolytic anaemia and 49 hospitalised dogs without primary cardiac or haematological disorders. Results : Dogs with primary haemolytic anaemia have higher serum concentrations of cardiac troponin I than hospitalised ill dogs (P<0.005) and healthy dogs (P<0.01). Using a cut‐off of less than 0.1 ng/mL, 20 of 27 dogs with primary haemolytic anaemia had increased serum cardiac troponin I concentrations, which was a significantly higher proportion compared to the hospitalised ill dogs (P<0.001, 16 out of 49 dogs) and healthy dogs (P<0.05, 3 out of 11 dogs). Clinical Significance : Dogs with primary haemolytic anaemia have a higher incidence of subclinical myocyte damage than healthy dogs or dogs with non‐haematological or primary cardiac illnesses. The prognostic significance of increased serum cardiac troponin I concentrations in dogs with primary haemolytic anaemia merits further investigation.