Exquisite response to intravenous immunoglobulin in Susac syndrome during pregnancy

INTRODUCTION: From its initial report on two female patients in 1979 by J.O. Susac, Susac syndrome (SuS) or SICRET (small infarctions of cochlear, retinal and encephalic tissue) has persisted as an elusive entity. To date the available evidence for its treatment is based on case reports and case series. The largest systematic review described only 304 reported cases since the 1970s. Here we presented the first reported case to our knowledge in Mexican population and the unusual presentation in a pregnant patient. CASE PRESENTATION: A 34-year-old Hispanic woman was brought to the ER in our hospital for apathy and behavioral changes. Upon arrival at the ER, her husband described a one-month history of behavioral changes with apathy, progressive abulia, visuospatial disorientation, and gait deterioration. The initial lab test shows no significance except by a positive qualitative hCG. An MRI was obtained and showed hyperintense periventricular white matter lesions in T2 and FLAIR sequences also involving bilateral basal ganglia and with predominant affection of the corpus callosum, in addition to infratentorial cerebellar lesions. After treatment with intravenous immunoglobulins a marked and prompt clinical and radiological improvement was observed. CONCLUSION: SuS is still an elusive disease. To date, no definitive score or clinical feature can predict the outcome of the disease. The presentation during pregnancy is also rare and therefore the optimal treatment and the prognosis is unknown. We hope that this article will serve as a foundation for future research.