A 35-year-old Japanese man was admitted to our hospital with recurrent
meningoencephalitis of unknown etiology. He presented with
fever, convulsions and
loss of consciousness, which started at age 33. We diagnosed him with neuro-Sweet disease (NSD) based on
human leukocyte antigen (
HLA) B-54/Cwl positivity and neutrophilic infiltration into the dermis in a biopsied skin plaque. Intravenous
methylprednisolone and oral
prednisolone markedly improved his
fever and CSF
pleocytosis. Five years later he was again admitted to our hospital with high
fever, oral
aphthae and dull-red edematous plaques on the face and body. He was conscious, but he had neck stiffness, mild
hyperreflexia in all limbs and an extensor plantar response. Laboratory tests revealed increased white blood cell, erythrocyte sedimentation rate (ESR) and
C-reactive protein level. CSF analysis indicated mild
pleocytosis. A skin biopsy from an edematous plaque revealed neurotrophils infiltrating the upper dermis. We treated him with intravenous
methylprednisolone (1 g/day) for 3 days, followed by oral
prednisolone (50 mg/day). His symptoms improved remarkably; however, he had recurrence of symptoms, such as
fever, meningial irritation and oral aphtae, with attempted taper of
prednisolone. We started treatment with
dapsone (75 mg/day) in addition to
prednisolone, and could taper oral
prednisolone, without a relapse. However, because some mildly recurred with the tapering of dapson, we maintained
dapsone treatment at 75 mg daily, added
colchicine (1 mg/ day) and tapered only
prednisolone. His symptoms were improved and no relapse has been observed. NSD is characterized by neurotrophic hyperactivation and infiltration of tissues. It is highly responsive to systemic
corticosteroid therapy; however, some cases show frequent recurrences on tapering of
corticosteroids.
Dapsone is considered to prevent neurotrophic overactivity. In this case,
dapsone was supposed to be effective to prevent reccurence of NSD upon tappering
corticosteroids.
Dapsone should be a therapeutic options for
steroid-dependent NSD showing frequent recurrence.