A 1-week course of corticosteroids in the treatment of eosinophilic meningitis

Eosinophilic meningitis is commonly found in Thailand and other Asian-Pacific countries. Angiostrongylus cantonesis, a nematode, is the most common cause of the disease (1Chotmongkol V. Sawanyawisuth K. Thavornpitak Y. Corticosteroid treatment of eosinophilic meningitis.Clin Infect Dis. 2000; 31: 660-662Crossref PubMed Scopus (128) Google Scholar, 2Punyagupta S. Juttijudata P. Bunnag T. Eosinophilic meningitis in Thailand. Clinical studies of 484 typical cases probably caused by Angiostrongylus cantonensis.Am J Trop Med Hyg. 1975; 24: 921-931Crossref PubMed Scopus (178) Google Scholar, 3Vejjajiva A. Parasitic diseases of the nervous system in Thailand.Clin Exp Neurol. 1978; 15: 92-97PubMed Google Scholar, 4Tsai H.C. Liu Y.C. Kunin C.M. et al.Eosinophilic meningitis by Angiostrongylus cantonensisreport of 17 cases.Am J Med. 2001; 111: 109-114Abstract Full Text Full Text PDF PubMed Scopus (141) Google Scholar). Humans get these parasites by eating raw snails or by eating food contaminated with snail excrement. A 2-week course of 60-mg prednisolone has been shown to relieve headache and reduce the number of lumbar punctures without any serious side effects. Eighty percent of patients were free of headache within 1 week of treatment, and there was no recurrent meningitis (1Chotmongkol V. Sawanyawisuth K. Thavornpitak Y. Corticosteroid treatment of eosinophilic meningitis.Clin Infect Dis. 2000; 31: 660-662Crossref PubMed Scopus (128) Google Scholar). We did a prospective cohort study to evaluate the efficacy of a 1-week course of corticosteroid treatment in patients with eosinophilic meningitis. The diagnosis of eosinophilic meningitis was made clinically (headache with history of eating raw snails and a cerebrospinal fluid eosinophil count of >10%). All patients were evaluated for severity of headache by visual analogue scale (VAS) and routine laboratory tests. Prednisolone 60 mg/d in three divided doses was given to all patients who did not have a contraindication to corticosteroid. We followed all patients clinically. We completely evaluated 52 patients between August 2002 and March 2004. Forty-seven patients (90%) were symptom free within 1 week, with a mean duration of symptoms of 4.8 days. Only 1 patient needed repeat lumbar puncture. Headache was improved after lumbar puncture, with a 63.29% decline in the VAS rating (Table).TableClinical Variables of the 52 PatientsVariablesNumber (%), Mean ± SD, or PercentageVAS at initial, mean8.23 ± 0.58VAS after lumbar puncture Mean3.02 ± 0.55 Decrease (%)63.29Patients who recovered at 1 wk47 (90)Patients who needed repeat lumbar puncture1 (0.02)Relapsed patients8 (15)Relapsed patients who needed additional treatment6 (12)VAS = visual analog scale. Open table in a new tab VAS = visual analog scale. At follow-up, 8 patients (15%) had relapsed within 2 weeks (Table). Two patients needed no further treatment because the headaches were not severe (VAS, 2 and 3); 1 of these patients recovered at day 12, the other at day 13. The other 6 patients needed additional treatment, such as lumbar puncture or prednisolone. All relapsed patients recovered by day 22. Minor adverse events, such as cushinoid face, acne, and dyspepsia were reported. The mechanism to explain the symptoms of headache in eosinophilic meningitis has not yet been established. On autopsy, dead parasites were found in patients who had had severe eosinophilic meningoencephalitis (5Tangchai P. Nye S.W. Beaver P.C. Eosinophilic meningoencephalitis caused by angiostrongyliasis in Thailand. Autopsy report.Am J Trop Med Hyg. 1967; 16: 454-461PubMed Google Scholar, 6Sonakul D. Pathological findings in four cases of human angiostrongyliasis.Southeast Asian J Trop Med Public Health. 1978; 9: 220-227PubMed Google Scholar); therefore, we believe that the presence of dead parasites causes meningeal inflammation. Prednisolone can improve headache symptoms by reducing the inflammatory process. A 1-week course of corticosteroid showed the same beneficial effect as a 2-week course in increasing the number of patients who felt free from headache. The relapsed patients may still have had residual inflammatory process. Because of the small number of subjects in our study, we could not assess the predictive factors of relapse. Therefore, we suggest that a 1-week course of corticosteroid treatment is also effective to treat eosinophilic meningitis, but that clinicians should be aware of possible relapse.