Presence of free light chains in urine of patients suffering from subacute sclerosing panencephalitis.

The immunoelectrophoretic analysis of CSF of patients suffering from subacute sclerosing panencephalitis (SSPE) showed modifications in the IgG pattern. Using the same method and also the double diffusion in agar technique we have revealed in these patients the presence of free light chains in most urines studied. Isofocusing analysis of free light chains from urines of two patients suggests that these chains could be a monoclonal product.