Presumed secondary immune-mediated haemolytic anaemia following elapid snake envenomation and its treatment in four dogs.

CASE SERIES: This case series describes secondary immune-mediated haemolytic anaemia (IMHA) in four dogs following elapid snake envenomation and its treatment. All the dogs initially presented with clinical signs commensurate with mainland tiger snake (Notechis scutatus) envenomation. None of the dogs was anaemic at the time of presentation. IMHA was diagnosed 3-9 days following snake envenomation. The trigger for IMHA was unclear in each case and may have been a component of the snake venom, antivenom, fresh frozen plasma, concurrent morbidity, administered drugs or a combination thereof. Three of the four dogs received immunosuppressive therapy comprising corticosteroids with or without azathioprine. Resolution of the IMHA was documented 6 weeks after diagnosis for one dog and 9 months after diagnosis for two dogs, with one dog lost to follow-up.

CONCLUSION: IMHA is a potential complicating factor of elapid snake envenomation and its treatment in dogs, and should be considered as a differential diagnosis for a persistent or worsening anaemia. Both the incidence and aetiopathogenesis of IMHA in the context of elapid snake envenomation and its treatment in dogs are unknown and require further examination.