Progressive cerebellar degeneration revealing Primary Sjögren Syndrome: a case report

BACKGROUND: Cerebellar ataxia represents a rare and severe complication of Sjӧgren syndrome (SS), especially with a progressive onset and cerebellar atrophy on imaging. CASE PRESENTATION: We report the case of a 30-year-old woman, with a past history of dry eyes and mouth, who presented a severe cerebellar ataxia worsening over 4 years associated with tremor of the limbs and the head. Brain MRI showed bilateral hyperintensities on T2 and FLAIR sequences, affecting periventricular white matter, with marked cerebellar atrophy. Complementary investigations confirmed the diagnosis of primary SS (pSS). The patient was treated by methylprednisolone, Cyclophosphamid and Azathioprine. Her clinical and radiological states are stabilized after 2 years of following. Primary cerebellar degeneration is extremely rarely associated with pSS. Few cases of isolated cerebellar ataxia or belonging to a multifocal disease were reported in the literature, most of them characterized by an acute or rapidly progressive onset. Cerebellar atrophy was described in only three patients. There have been few clarifications of the pathogenesis of the neurological manifestations in pSS. Treatment is based on corticosteroids and immunosuppressive agents with no consensus of a specific therapy. CONCLUSIONS: Cerebellar ataxia due to pSS may exceptionally mimic a degenerative cerebellar ataxia, especially when the onset is progressive, which represents the particularity of our observation. The role of brain MRI and antibodies remains important for the differential diagnosis.