Angiostrongylus cantonensis: Effect of combination therapy with albendazole and dexamethasone on Th cytokine gene expression in PBMC from patients with eosinophilic meningitis

To determine how combination therapy with albendazole and dexamethasone changed cytokine responses in peripheral blood mononuclear cells (PBMC) in patients with eosinophilic meningitis caused by Angiostrongylus cantonensis (EOMA), we measured mRNA levels of Th2 (IL-5, IL-4 and IL-10) and Th1 (IL-2 and IFN-γ) cytokines with reverse transcription polymerase chain reaction (RT-PCR). Forty-three patients were divided into three groups: group 1 (pre-treatment, 13 patients), group 2 (7 days post-treatment, 14 patients), and group 3 (30 days post-treatment, 16 patients). Peripheral eosinophil counts were also measured. EOMA patients showed higher levels of Th2 cytokines, including IL-5 and IL-10, and peripheral eosinophil counts, but no changes in IL-4 or Th1 cytokines. Combination therapy reduced IL-5 mRNA expression and peripheral eosinophil counts to control levels, but increased IL-10, IL-2, and IFN-γ mRNA expression, and did not change IL-4 levels. These data suggest that systemic Th2 cytokine responses, especially IL-5, and peripheral eosinophil counts increased in EOMA patients. Combination therapy with albendazole and dexamethasone can shift the cytokine responses from Th2 to Th1 dominance, which may be a therapeutic mechanism.