Primary lateral sclerosis: disease, syndrome, both or neither?

Swash, Desai, and Misra [ [1] Swash M. Desai J. Misra V.P. What is primary lateral sclerosis. J Neurol Sci. 1999; 170: 5-10 Abstract Full Text Full Text PDF PubMed Scopus (43) Google Scholar ] use two patients with primary lateral sclerosis (PLS) as the foundation for a history-based discussion of that elusive condition. They conclude that it is a form of motor neuron disease and often turns into amyotrophic lateral sclerosis (ALS) before death. Their inclusionary and exclusionary criteria for the clinical diagnosis of PLS are the generally accepted ones. However, there is no way to prove the diagnosis except by autopsy, which has been performed in only 6 cases since the ‘modern era’ started in 1977 with a report by C. Miller Fisher [ 2 Fisher C.M. Pure spastic paralysis of corticospinal origin. Can J Neurol Sci. 1977; 4: 251-258 PubMed Google Scholar , 3 Younger D.S. Chou S. Hays A.P. Lange D.J. Emerson R. Brin M. Thompson Jr., H. Rowland L.P. Primary lateral sclerosis. A clinical diagnosis reemerges. Arch Neurol. 1988; 45: 1304-1307 Crossref PubMed Scopus (118) Google Scholar , 4 Pringle C.E. Hudson A.J. Munoz D.G. Kiernan J.A. Brown W.F. Ebers G.C. Primary lateral sclerosis. Clinical features, neuropathology and diagnostic criteria. Brain. 1992; 115: 495-520 Crossref PubMed Scopus (357) Google Scholar ]. It is reasonable to start in 1977 because, at the time of the earliest reports serological tests for syphilis and viral infections were not available and B12 deficiency could not be identified; myelography and electromyography were not widely available before 1945. CT did not come until 1973 and MRI was even later.