[Specific count of cerebrospinal fluid cells in the counting chamber using supravital staining]

The authors adapted to the cerebrospinal fluid (CSF) the staining technic developed by Anguiano and Ancira to perform differential leucocyte counts in the counting chamber. The formula they used is the following: methyl alcohol 1 ml, distilled water 2 ml. To this mixture are added: 6 drops of Leishman stain filtered in Whatman paper number 42; toluidine blue 0.25% aqueous solution (filtered in the same manner), 1 drop; acetate buffer 0.1 M, pH 5.4, 1 drop. The technic varies according to the intensity of pleocytosis. If the CSF is turbid or contains more than 100 cells per c.m. 1 drop is dripped in the bottom of a 10X75 test tube and then 2 drops of the staining fluid are added; the mixture is then shaken; after one or two minutes 1 drop is placed in the Fuchs-Rosenthal counting chamber. If the number of total cells is less than 100 per c.m. different CSF volumes are centrifuged at the rate of 2000 r.p.m., during 6 minutes; the supernatant fluid is poured off and the sedimented cells are suspended in 2 drops of the staining fluid. The morphology of the cells as they appear after they are stained by the supravital staining technic (SVST) is described and illustrated in photomicrographies.(ABSTRACT TRUNCATED AT 250 WORDS)