Diagnostic and therapeutic dilemmas

Close blood relatives of MS patients have MRI changes suggestive of MS despite the absence of any symptoms. They have also been seen when an MRI is obtained for various reasons in unrelated persons. This raises questions regarding their clinical significance, if any, since typical MS plaques have been found at autopsy in eloquent parts of the nervous system in completely asymptomatic individuals. Do these people have MS and should immunomodulatory treatment be considered? Because they are not ill according to various dictionary definitions, no to both. A higher rate of MS in close blood relatives would be expected due to the known genetic susceptibility, but suggestive MRI changes are quite uncommon, even in unaffected twins. Finally, a review of the four published studies of MS lesions unexpectedly found at autopsy in neurologically asymptomatic persons revealed a prevalence of the disease of 0.1%, the same as the estimated prevalence of clinical MS in the United States.