[Two cases of natural infection of Angiostrongylus cantonensis in cynomolgus monkeys (Macaca fascicularis) (author's transl)].

Two of 80 cynomolgus monkeys, Macaca fascicularis, imported from Indonesia showed weakness, anorexia, paralysis of extremities and dysstasia. The blood test conducted at the time of autopsy proved that the white blood cell count markedly decreased in both cases and the blood urea nitrogen content increased in Case No. 1. In Case No. 2, a high blood sugar value, a low red blood cell count and a low hematocrit value were recognized. Histologic examinations revealed the presence of fragments of a nematode in the subarachnoid space of the cerebrum, granular layer of the cerebellum and gray matter of the cervical spinal cord. The findings of eosinophilic meningitis, necrosis, foreign body giant cells and cellular infiltration predominantly with eosinophils were also noted there. Morphological features of the nematode found in the tissue sections were identical, in all respects, with those described by predecessors who made morphological observations on the cross sections of Angiostrongylus cantonensis. Immunoelectrophoretic analyses of sera from these monkeys demonstrated the presence of band "a", which has been described to be highly specific to human A. cantonensis infection. Based on the above-mentioned evidences, the parasite fragments found in the histological sections from the monkeys were identified as A. cantonensis. The cases of natural infection reported herein represent the first, to our knowledge, in which migration of A. cantonensis larvae in the central nervous system of monkey was demonstrated. The present observation suggests applicability of simian angiostrongyliasis as a model for infections in man.