Antigenuria in St. Louis encephalitis.

Patients with St. Louis encephalitis may have urinary tract symptoms when they develop manifestations related to involvement of the central nervous system. During 1976, 12 patients with St. Louis encephalitis were studied for the presence of antigenuria, and compared to controls. Although virus isolation attempts were negative indirect immunofluorescence, electron microscopy, and immune electron microscopy demonstrated the presence of viral antigen in urine. Further study of antigenuria in St. Louis encephalitis is needed to delineate the pathophysiology of the lower urinary tract symptoms and to determine whether this phenomenon might furnish the basis for a rapid diagnostic test for the disease.