Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a severe reaction to a drug that manifests with a wide variety of symptoms, typically several weeks after initial drug exposure. DRESS can involve multiple organ systems in addition to skin rash, eosinophilia, fever, renal, and liver abnormalities. Posterior reversible encephalopathy syndrome (PRES) is a cerebrovascular autoregulatory disorder hypothesized to occur from breakdown of the blood-brain barrier with multiple risk factors including hypertension as a common component. Neuroimaging findings of PRES in children have been noted to vary from those in adults. Children tend to have atypical findings of edema in regions such as the frontal, temporal, basal ganglia, brainstem, and cerebellum, in contrast to adults who usually present with parieto-occipital distribution. We present a unique case of DRESS and discuss imaging findings of atypical PRES in a child complicating treatment of an intracranial subdural empyema. A 5-year-old male patient underwent craniotomy and functional endoscopic sinus surgery for initial management of left pansinusitis complicated by a subdural empyema. The patient presented to the emergency room 3 weeks later with fever and a morbilliform rash and was diagnosed with DRESS, presumed secondary to a phenobarbital reaction. Initial imaging findings on abdominal ultrasound included hepatosplenomegaly, gallbladder wall thickening with cholelithiasis, pleural effusion, and findings consistent with bilateral nephritis. Subsequent imaging corroborated findings with increasing renal size and echogenicity commensurate with renal dysfunction in conjunction with steroid treatment for DRESS resulting in hypertensive crisis. Together with worsening encephalopathy, brain MRI confirmed presumed diagnosis of atypical PRES with diffusion negative increased cortical and subcortical white matter T2/FLAIR signal, indicating edema in an pattern involving watershed zones including bilateral posterior parietal, temporal, occipital lobes, left frontal lobe, and cerebellum. This report illustrates an interesting case of PRES as a complication of DRESS syndrome in a pediatric patient formerly treated with craniotomy for an intracranial subdural empyema. We highlight the importance of including PRES on the differential in a patient with severe hypertension. The radiologist should be familiar with the atypical PRES pattern which is more commonly seen in children compared to adults. Read More

Meeting name: SPR 2024 Annual Meeting & Postgraduate Course , 2024

Authors: Guo Grace, Marcelo Karina, Clarion Michael, Naun Christopher, Rooks Veronica

Keywords: Acute hypertensive encephalopathy, Cerebrovascular autoregulatory disorder