Patient selection: meningitis or encephalitis.
Clinical diagnostic criteria for angiostrongyliasis:
(1) CSF WBC count >= 10 µL
(2) percent eosinophils in CSF differential count >= 10%
(3) history of ingesting raw freshwater snails or other intermediate hosts for Angiostrongylus (monitor lizards, shrimp, etc).
(4) exclusion of other possible explanations
where:
• The intermediate hosts or the patient should be from an endemic area for Angiostrongylus cantonensis.
• Items 1 and 2 are used by Ramirez-Avila et al to define eosinophilic meningitis, referencing Kuberski T. Ann Intern Med. 1979; 91: 70-75.
Exclusion critiera:
(1) positive CSF studies for bacteria
(2) positive CSF studies for mycobacteria or past history of tuberculosis
(3) positive CSF studies for Cryptococcus or other fungi
(4) history of eating raw fish
(5) history of migratory swellings
(6) diagnosis of subarachnoid hemorrhage
(7) diagnosis of myeloencephalitis
(8) positive serologic test for gnathostomiasis
(9) positive serologic test for cysticercosis or clinical evidence of cysticercosis
(10) abnormal brain CT or MRI
(11) history of malignancy
(12) HIV-positive
The clinical criteria are presumptive, pending serologic evidence of demonstration of the larvae.
