Spinal Sarcoidosis

Abstract

Sarcoidosis is a relatively benign and indolent granulomatous disease of uncertain etiology occurring in young persons. Involvement of almost every organ has been described. Neurological lesions are relatively infrequent and the spinal cord is affected less often than the brain. It is the purpose of this paper to list reported information concerning spinal sarcoidosis, to describe an example of involvement of the spinal cord, and to show how myelography may be useful in establishing the diagnosis. Incidence and Pathology The true incidence of involvement of the nervous system in sarcoidosis is difficult to determine. Some portion of it is probably affected in approximately 1 per cent of patients (Ricker and Clark, 14; Höök, 7). Transient meningeal reactions without neurologic symptoms and signs, as manifested by cerebrospinal fluid changes, may occur much more frequently as a part of the generalized systemic reaction (Pennell, 12; Harrell and Fisher, 6). Disorders of the spinal portion of the central nervous system from focal intramedullary or extramedullary meningeal lesions are apparently very unusual. Verified examples of spinal cord involvement in sarcoidosis are rare (Table I). The gross pathologic changes of sarcoidosis of the central nervous system usually are manifested as a leptomeningitis and less frequently as intracerebral or intramedullary granulomata (Longcope and Freiman, 10). The leptomeninges at the base of the brain are most commonly affected. Neural parenchyma may be involved by direct extension from the meninges. Often cranial and spinal nerves become diseased. In the few examples of spinal sarcoidosis studied at necropsy, the meningeal changes in the vertebral canal were found to be similar to those commonly encountered in the basal cisterns, and granulomatous extension into the spinal cord was demonstrable (Longcope, 9; Erickson et al., 4; Aszkanazy, 1; Jefferson, 8). Microscopically the central nervous system lesions of sarcoidosis are found to arise in perivascular spaces of the meninges. The arachnoid is infiltrated by lymphocytes, and granulomatous nodules become attached to the adventitia of small meningeal vessels (Aszkanazy, 1). The nodules are similar to sarcoid lesions occurring elsewhere in the body and consist of epithelioid cells, lymphocytes, plasma and other round cells, and giant cells, with varying degrees of fibrosis. The spinal lesions have been said to be less intense than those more commonly encountered at the base of the brain (Erickson et al., 4). Meningeal lesions alone may result in vascular insufficiency and atrophy of neural tissue. In acute cases, meningeal vascular changes may lead to thrombosis and infarction (Meyer et al., 11). Within the neural substance perivascular infiltrations similar to the meningeal lesions may be present, especially in the subependymal layer. In the deep neural lesions only a few giant cells and round cells may be found attached to very small vessels, and occasionally a few such cells are free in nervous tissue without vascular attachment.