Vaccine-associated immune-mediated hemolytic anemia in the dog.

  Duval D, Giger U.

  Department of Clinical Studies, School of Veterinary Medicine, University
of Pennsylvania, Philadelphia 19104-6010, USA.

  Vaccination has been incriminated as a trigger of immune-mediated
hemolytic anemia (IMHA) in dogs and in people, but evidence to support this
association is lacking. In a controlled retrospective study, idiopathic IMHA
was identified in 58 dogs over a 27-month period. When compared with a
randomly selected control group of 70 dogs (presented for reasons other than
IMHA) over the same period, the distribution of cases versus time since
vaccination was different (P < .05). Fifteen of the dogs (26%) had been
vaccinated within 1 month (mean, 13 days; median, 14 days; range, 1 to 27
days) of developing IMHA (P < .0001), whereas in the control group no marked
increase in frequency of presentation was seen in the first month after
vaccination. The dogs with IMHA were divided into 2 groups based on time
since vaccination: the vaccine IMHA group included dogs vaccinated within 1
month of developing IMHA; the nonvaccine IMHA group included dogs that
developed IMHA more than 1 month after vaccination. The recently vaccinated
dogs with IMHA (vaccine IMHA group) had significantly lower platelet counts
(P < .05) and a trend towards increased prevalence of intravascular
hemolysis and autoagglutination when compared with the nonvaccine IMHA
group. Similar mortality rates were seen in teh vaccine IMHA group (60%) and
the nonvaccine IMHA group (44%), with the majority of fatalities (> 75%)
occurring in the first 3 weeks after presentation. Persistent
autoagglutination was a negative prognostic indicator for survival in both
groups (P < .05). Presence of icterus and hyperbilirubinemia were negative
prognostic indicators for survival in the nonvaccine IMHA group (P < .0001
and P < .01, respectively) but not in the vaccine IMHA group. In the
recently vaccinated dogs, combination vaccines from various manufacturers
against canine distemper, adenovirus type 2, leptospirosis, parainfluenza,
and parvovirus (DHLPP) were involved in each case. Vaccines against rabies
virus, Bordetella spp, coronavirus, and Lyme Borrelia were administrated
concomitantly to some dogs. This study provides the first clinical evidence
for a temporal relationship of vaccine-associated IMHA in the dog.

  PMID: 8884713 [PubMed - indexed for MEDLINE]