Trimethoprim and sulfonamide-associated meningoencephalitis with MRI correlates

Early recognition of trimethoprim and sulfonamide-induced aseptic meningitis is important because drug cessation leads to rapid clinical improvement. We present clinical and laboratory findings in two typical cases. In both cases, MRI revealed previously undescribed diffuse white matter abnormalities that resolved within a few months. These MRI findings are important because they may aid in early diagnosis of this condition in the appropriate clinical setting. In addition, the white matter abnormalities suggest an encephalitic component in addition to the meningitis.