Diagnosis of Angiostrongyliasis If meningitis signs are present, cerebrospinal fluid (CSF) analysis and complete blood count (A cantonensis) Sometimes identification of eggs and larvae in tissue obtained during abdominal surgery (A costaricensis) Angiostrongyliasis is suspected based on a history of ingesting potentially contaminated material, including land snails, slugs, or transfer hosts such as certain land crabs, frogs, toads, or freshwater prawns or shrimp.