Concomitant Acute Toxic Leukoencephalopathy and Posterior Reversible Encephalopathy Syndrome

Abstract

Concomitant "ATL-PRES" was found in 2.2% of the patients in a large cohort of ATL and PRES. Etiologies varied. Clinical symptoms and MRI findings were potentially reversible.

Acute Toxic Leukoencephalopathy: Etiologies, Imaging Findings, and Outcomes in 101 Patients

“…The exact pathophysiology of ATL is also unknown, but the evidence shows that white matter damage may occur directly from toxic injury on the myelin sheath or indirectly from capillary endothelial injury or a combination of both. [2][3][4]13 For example, carbon monoxide and inhaled opiates may cause either toxic demyelination or spongiform degeneration of the PVWM. 5,19 While chemotherapeutics such as fludarabine and methotrexate can cause direct toxic damage of the axons and myelin sheath, chemotherapeutic agents, such as methotrexate and 5-flourouracil, and immunosuppressive agents, such as tacrolimus and cyclosporine, were shown to disrupt the cerebral microvasculature.…”

“…35 Furthermore, a recent study focused on concomitant ATL and PRES in a small cohort (a subset of patients excluded from this study) in which most had kidney failure and perhaps uremia. 13 It is not known how uremia causes toxic leukoencephalopathy; however, diffusion tensor imaging studies found premature PVWM disease, especially in the anterior PVWM in patients with chronic kidney disease, and various uremic toxins may cause both endothelial dysfunction and cognitive impairment, especially via neuroexcitatory uremic-guanidine compounds. 36,37 Given the number of patients with uremia in this study, it is plausible that uremia may exacerbate ATL or even predispose to ATL in the absence of other toxins.…”

“…Because there are overlapping etiologies that may cause both ATL and PRES, the neuroradiologists ensured that there was no cortical edema, which has been described as the earliest manifestation of PRES; thus, patients were included only if they had reduced diffusion involving the white matter. [11][12][13] Inclusion criteria for formal review (of imaging severity and outcome) included, at a minimum, the following: MR imaging within 3 weeks of presentation, including DWI with ADC maps, and FLAIR images obtained in the acute setting when patients were still symptomatic, either in the pretreatment or early treatment era, as well as MR imaging with reduced diffusion in the white matter suspicious for ATL. 2 Patients were excluded if there was a lack of DWI or ADC maps, lack of measured ADC reduction, CTL or MR imaging findings not suggestive of ATL (eg, predominantly cortical edema), other PVWM disorders with reduced diffusion (eg, lymphoma, primary brain tumor, infarction, trauma); or they were younger than 10 years of age or had infectious disorders, hypoxic-ischemic insults, leukodystrophies, severely compromised MR imaging data, clinical findings not indicating ATL (eg, lack of acute neurologic symptoms, discordance between clinical and radiologic findings), and potential confounding conditions (eg, cranial metastasis or the presence of leptomeningeal enhancement) ( Fig 1).…”

Sequential occurrence of eclampsia-associated posterior reversible encephalopathy syndrome and reversible splenial lesion syndrome (a case report): proposal of a novel pathogenesis for reversible splenial lesion syndrome

“…PRES and ATL have been described by McKinney et al, and have overlapping etiologies [5, 7]. The etiologies of RESLES may overlap with PRES and ATL, it also likely involves a component of endothelial injury and perhaps toxic demyelination [8, 9], which has been suggested as both a cause of PRES and ATL, based on histopathology.…”

“…However, the underlying pathophysiological mechanism remains unknown. There are scant, if any, cases described of concomitant PRES- RESLES(MERS), although preliminary cases of acute toxic leukoencephalopathy (ATL) have been described with PRES [5]. Here we report a rare case involving a 23-year-old pregnant woman with eclampsia who sequentially developed PRES and RESLES.…”