Baylisascaris procyonis larva migrans in a puppy: a case report and update for the veterinarian.

Baylisascaris larva migrans (LM) has been recognized as a cause of central nervous system (CNS) disease in puppies. A presumptive antemortem diagnosis is based on a history of raccoon exposure, clinical signs, cerebrospinal fluid eosinophilic pleocytosis, and peripheral blood eosinophilia. Early diagnosis is critical for treatment or prevention of disease in other dogs, animals, or humans exposed to the suspected contaminated area. In the present case, an antemortem diagnosis was not made, emphasizing the importance of postmortem examination in cases of CNS disease in puppies.