BILATERAL, REVERSIBLE, SELECTIVE THALAMIC INVOLVEMENT DEMONSTRATED BYBRAIN MR AND ACUTE SEVERE NEUROLOGICAL DYSFUNCTION WITH FAVORABLE OUTCOME

We report on two children who presented acute, severe, neurological dy sfunction with bilateral, reversible, selective thalamic lesions demon strated by brain MRI. In both children neurological symptoms appeared two weeks after a febrile respiratory illness. Clinical conditions wor sened in a few days to a stuporous state and tetraplegia in one and to coma with decerebrate posturing in the other. Three weeks after the o nset, both children improved and recovered within one month. During th e acute phase, brain MRT showed in both children bilateral hyperintens e areas on T2-weighted sequences limited to both thalamic regions. Dur ing the follow-up, repeated brain MRI showed complete disappearance of abnormalities in one patient and a small residual left thalamic lesio n in the other. In both patients hematological routine exams were norm al. Bacterial and viral studies of serum and CSF were negative. CSF fi ndings showed elevated white blood cell count and protein levels, with no oligoclonal IgG bands. Urine and CSF organic acids by GC/MS and pl asma as well as CSF aminoacids were normal. We believe that the benign evolution of this disorder and CSF findings strongly suggest a postin fectious process of the central nervous system.