The chemical analysis of the CSF typically resembles the findings in "aseptic meningitis" with slightly elevated protein levels, normal glucose levels, and negative bacterial cultures. Presence of a significantly decreased glucose on CSF analysis is an indicator of severe meningoencephalitis and may indicate a poor medical outcome. Initial CSF analysis early in the disease process may occasionally show no increase of eosinophils, only to have classical increases in eosinophils in subsequent CSF analysis. Caution should be advised in using eosinophilic meningitis as the only criterion for diagnosing angiostrongylus infestation in someone with classic symptoms, as the disease evolves with the migration of the worms into the CNS.Eosinophils are specialized white blood cells of the granulocytic cell line, which contain granules in their cytoplasm. These granules contain proteins that are toxic to parasites. When these granules degranulate, or break down, chemicals are released that combat parasites such as A. cantonensis. Eosinophils, which are located throughout the body, are guided to sites of inflammation by chemokines when the body is infested with parasites such as A. cantonensis. Once at the site of inflammation, type 2 cytokines are released from helper T cells, which communicate with the eosinophils, signaling them to activate. Once activated, eosinophils can begin the process of degranulation, releasing their toxic proteins in the fight against the foreign parasite.
Freshwater snails: Pila spp., Pomacea canaliculata, Cipangopaludina chinensis, Bellamya aeruginosa and Bellamya quadrata
Slugs: Limax maximus, Limax flavus Deroceras laeve, Deroceras reticulatum, Laevicaulis alte, Sarasinula plebeia, Vaginulus yuxjsjs, Lehmannia valentiana, Phiolomycus bilineatus, Macrochlamys loana, Meghimatium bilineatum and probably other species of slugs.Definitive hosts of A. cantonensis include wild rodents, especially the brown rat (Rattus norvegicus) and the black rat (Rattus rattus).Paratenic hosts of A. cantonensis include the predatory land flatworm Platydemus manokwari and the amphibians, Bufo asiaticus, Rana catesbeiana, Rhacophorus leucomystax and Rana limnocharis.In 2004, a captive yellow-tailed black cockatoo (Calyptorhynchus funereus) and two free-living tawny frogmouths (Podargus strigoides) suffering neurological symptoms were shown to have the parasite. They were the first avian hosts discovered for the organism. In 2018, in Mallorca two North African hedgehogs with signs of acute neurological disease were found to have A. cantonensis in their brains, one of them with a gravid female. It was the first report of hedgehogs as hosts of Angiostrongylus.The Hawaiʻi Dept. of Health states that fresh water opihi can carry the parasite, as well as other aquatic organisms such as prawns, frogs, and water monitor lizards. House pets may interact with A. cantonensis-carrying animals yet not well studied. Cats are known to carry and spread feline lungworm in rat and snail interactions. Pathogenesis of human angiostrongylosis
The presence of parasitic worms burrowed in the neural tissue of the human central nervous system (CNS) causes complications.