A potential new role for ASL perfusion imaging: Diagnosis of metronidazole induced encephalopathy – Two companion cases

Abstract

Metronidazole induced encephalopathy (MIE) is a rare condition due to prolonged high dose administration of metronidazole. MIE with corresponding increased perfusion on MRI arterial spin labeling (ASL) of the involved regions of the brain appears not to have been reported in the literature to date. We present two such cases, a 59-year-old male with recurrent C difficile colitis with classic MR imaging characteristics of MIE, and a companion case of a 65-year-old female with gangrenous cholecystitis also presumed to have MIE. Despite aggressive medical management, both patients expired. Our cases demonstrate a correlation with ASL hyperperfusion to affected brain regions thought to be due to edema or inflammation. Perfusion imaging may play a role in diagnosis of MIE.

Clinical application of brain perfusion imaging in detecting stroke mimics: A review

“…In contrast to stroke, perfusion abnormalities in this patient were diffuse, not respecting the boundaries of vascular territories 92 . However, Yedavalli and Lanzman detected bilaterally increased signal restricted to the dentate nuclei and splenium on ASL sequences 93 . Characteristic MRI findings such as hyperintensity of the dentate nucleus and splenium of the corpus callosum on fluid‐attenuated inversion recovery images, seen in both studies, can distinguish this encephalopathy from acute ischemic stroke 94 …”

“…92 However, Yedavalli and Lanzman detected bilaterally increased signal restricted to the dentate nuclei and splenium on ASL sequences. 93 Characteristic MRI findings such as hyperintensity of the dentate nucleus and splenium of the corpus callosum on fluid-attenuated inversion recovery images, seen in both studies, can distinguish this encephalopathy from acute ischemic stroke. 94 Another rare condition that can mimic stroke is contrast-induced encephalopathy (CIE).…”

Stroke mimics: A review

“…It has the clinical features of cerebellar dysfunction, altered mental status and extrapyramidal symptoms [85]. The classical manifestations of MIE on MR are as follows: the splenium of the corpus callosumas shows T2 hyperintensity and the dentate nucleus and/or brainstem shows symmetric T2 lesions [86].…”