Clinical and MRI Characteristics of Levamisole-Induced Leukoencephalopathy in 16 Patients

OBJECTIVE To study the clinical and radiological characteristics of levamisole-induced leukoencephalopathy (LILE) in patients with recurrent aphthous ulcers (RAU) or infected with Ascaris. METHODS The medical histories of 16 patients with LILE were analyzed, including clinical manifestations, brain magnetic resonance imaging (MRI) characteristics, cerebrospinal fluid, and brain biopsy findings. RESULTS The main clinical manifestations of LILE were motor weakness (75.0%), dysphasia or aphasia (50.0%), cognitive disorder (50.0%), and facial palsy (43.8%). The MRI of 16 cases showed plaque and round or oval demyelinating lesions in white matter, which revealed a signal hypointensity on T1-weighted and diffusion-weighted images (DWI), and demonstrated hyperintensity on T2-weighted and fluid-attenuated inversion recovery (FLAIR) images. The MRI revealed peripheral ring-type enhancement about the focus after Gd-DTPA administration and edema around some lesions, without mass effect. T2-weighted and FLAIR images were highly sensitive to the lesions. Brain biopsy in 1 patient showed multifocal demyelinating lesions without perivascular cuffing by lymphocytes. Treatment generally consisted of steroids and hyperbaric oxygen therapy, and patients recovered to normal condition. CONCLUSIONS A single normal dose of levamisole can induce leukoencephalopathy in patients with RAU or Ascaris. The diagnosis depends on the clinical features and imaging appearances. Steroid therapy might be a good choice of treatment.