First cases of spinal worm infection in dogs in Hawaii

Abstract

Two young dogs domiciled in Honolulu, Hawaii, were presented in November and December 2018 (respectively) for spinal hyperesthesia, hindlimb weakness, and proprioceptive ataxia. Both dogs had neurologic findings referable to spinal cord disease. Both dogs had a combination of lower motor neuron signs (reduced muscle mass, decreased withdrawal reflexes, low tail carriage) and long tract signs (conscious proprioceptive deficits, crossed extensor response, increased myotatic reflexes). Peripheral eosinophilia was present in the second case, but hematology and serum biochemistries were otherwise unremarkable. Plain radiographs and computed tomography scans ± contrast were unremarkable. Cerebrospinal fluid (CSF) from both patients demonstrated eosinophilic pleocytosis, and real-time polymerase chain reaction testing demonstrated Angiostrongylus cantonensis deoxyribonucleic acid in CSF, confirming a diagnosis of neuroangiostrongyliasis. Treatment included glucocorticoid therapy, ± anthelmintic (fenbendazole). Both dogs made a complete recovery. These are the first confirmed cases of autochthonous neuroangiostrongyliasis in canine patients in the United States and the first dogs anywhere to be diagnosed definitively with A cantonensis infection based on real-time polymerase chain reaction testing of CSF. A clinician examining a patient with severe spinal hyperesthesia and a combination of upper and lower motor signs should consider A cantonensis as a differential, especially in endemic areas.