Neuro-Sweet Syndrome: A Diagnostic Conundrum

Abstract

Sweet Syndrome presents as acute fever, leucocytosis and characteristic skin plaques. It can involve many organ systems but rarely affects the nervous system. We report the case of a 51-year-old female that presented with fever, rash, headache and encephalopathy. Brain magnetic resonance imaging showed extensive T2 hyperintensities involving cerebral hemispheres, cerebellum, and brainstem. A skin biopsy revealed dermal infiltration by neutrophils consistent with Sweet Syndrome. She started steroid treatment with a good clinical response. Further questioning revealed that she had a similar episode 10 years prior that had been diagnosed as acute disseminated encephalomyelitis. Neuro-Sweet Syndrome can present with a great array of symptoms and relapses over long periods of time making the diagnosis difficult without a high degree of suspicion. Clinicians should consider this syndrome in the setting of acute encephalitis with white matter lesions that are highly responsive to steroids particularly in the presence of previous similar symptoms.

Keywords: acute disseminated encephalomyelitis; delayed diagnosis; magnetic resonance imaging; sweet syndrome.

Figure 1.

MRI imaging from both of the patient’s neurologic presentations. (A) Selected FLAIR images from the patient’s MRI from her most recent presentation. There are bilateral FLAIR hyper-intense lesions with associated vasogenic edema and local mass effect, this time predominantly involving the left thalamus, left basal ganglia, right brainstem and right cerebellar hemisphere. No diffusion restriction or enhancement is present. (B) Selected FLAIR images are shown from an MRI from the patient’s first episode 10 years prior. Multiple FLAIR hyper-intense lesions are seen predominantly affecting the bilateral right greater than left basal ganglia and left cerebellar hemisphere. No diffusion restriction or enhancement was seen. (C) Selected FLAIR images at similar levels from the follow-up MRI approximately 1 month after initial presentation following treatment with steroids. These images demonstrate near complete interval resolution of the FLAIR signal abnormalities, edema and regional mass effect.

Figure 2.

Skin biopsy, H&E stain. (A) 10X and (B) 40X magnification images showing superficial dermal edema with dense neutrophilic infiltrate and karyorrhexis.