The cytology of the spinal fluid in poliomyelitis is of great diagnostic importance and is by many authors also credited with prognostic significance. In the differential diagnosis between poliomyelitis and other diseases of the central nervous system, tuberculous meningitis has a fluid resembling closely that of poliomyelitis. A graphic study, therefore, of the cell counts and the range of polymorphonuclears and a comparison of these curves with similar curves for tuberculous meningitis seem timely.
Chart 1 shows the curves for the cell counts in 122 cases of poliomyelitis and in 147 of tuberculous meningitis, the abscissa representing the number of cells and the ordinate the number of cases, reduced to a percentage basis in order that the two curves might be comparable.
Most of the cases of poliomyelitis show a cell count between 50 and 200, but a fair proportion (19.7 per cent) are below 50, and the curve drops