Posterior reversible encephalopathy syndrome during induction chemotherapy for acute myeloid leukaemia

Abstract

A 52-year-old man, treated for an acute myelo-monocytic leukaemia, presented on day 22 of the second induction cycle an altered mental status with drowsiness, slurred speech and an unstable gait without focal neurological signs. A non-contrast cranial CT showed only non-specific findings, whereas a 3-T MR showed bilateral occipital, mainly subcortical oedema on fluid attenuated inversion recovery (Fig. A) and on T2-weighted (Fig. B) images, but with no restriction on diffusion-weighted imaging (not shown). These findings are compatible with a vasogenic oedema and allow the diagnosis of posterior reversible encephalopathy syndrome (PRES). A mild hypertension, noted 2 days before symptom onset, was treated with amlodipine. Serum electrolytes were normal. The mental alteration returned to normal within 2 days without additional treatment. Fourteen days later, the MRI showed complete resolution of the changes in the occipital region. Posterior reversible encephalopathy syndrome is a condition characterized by changes in mental status, headache, visual disturbances or other focal neurological deficiencies and/or seizures together with symmetrical vasogenic oedema in the posterior cerebral areas, initially described in the context of severe hypertension. Loss of autoregulatory mechanisms of the cerebral blood flow and endothelial damage are thought to be involved in the pathogenesis. A variety of medical conditions were identified as potential triggers including several chemotherapeutic agents, biological therapies (monoclonal antibodies and small molecules) or immunosuppressants. Fluid overload, a reduced renal function and an increased blood pressure are further risk factors for PRES during chemotherapy. Management includes correction of hypertension, antiepileptic therapy for seizures and optimal treatment of concomitant medical conditions as electrolyte disturbances or infections. Progression to cytotoxic oedema is a rare event, whereas in most cases, PRES resolves completely with no residual neurological deficiencies.