Abstract: 【Abstract】 Objective To summarize the clinical features of severe angiostrongyliasis cantonensis (AC) patients. Methods Clinical data on symptoms，physical signs，auxiliary examination and prognosis of 25 severe AC patients hospitalized in June-Sept 2006 were analyzed. Results Epidemiologically，all cases had eaten uncooked fresh water snails. One of the early symptoms was fever (16 cases，64.0%)，including 8 cases with low-grade fever，7 cases with mid-range fever，and 1 case high fever. Nervous system manifestation：① All cases had headache，entire headache (56.0%)or partial(44.0%)，especially in occipitalis. ② Patients had distinct degree neck rigidity，with negative pathologic reflex；12 cases had nausea and vomiting(48.0%). ③ 20 cases(80.0%) had skin paresthesia，5 had severe pain and hyperalgia on skin；3 cases with skin numbness，and 2 with thermohypesthesia. ④ 11 cases(44.0%)appear distinct degree depraved vision；3 cases had photophobia，5 with blur vision，1 each with diplopia，defect of field vision or bug sign，respectively. ⑤ Nasolabial groove became shallow and distortion of commissure in 4 cases (16.0%)，and 2 cases(8.0%)couldn’t close up eyelid. ⑥ 4 cases had sustained or durative tinnitus. Laboratory examination showed that eosinophilic granulocytes increased in both peripheral blood and cerebrospinal fluid. Skull MRI for 14 cases revealed linear enhancement in local meninx or abnormal enhancement in cerebral parenchyma. Chest CT examination in 7 cases showed nodule shadow and spot flaky ground-glass shadow in lungs. One and 3 months after being discharged from hospital，12 patients(48.0%) still had sequelaes——7 cases had tingling sensation on skin，1 case had temperature sensation dysfunction on the skin of chest and abdomen，3 cases had headache occasionally，and 1 case still had defect of field vision. Conclusion Central nervous system has been impaired in the angiostrongyliasis cantonensis patients who may need a longer convalescent period.

Key words: Angiostrongyliasis cantonensis, Nervous system, Clinical observation