Recommendations for cerebrospinal fluid examination in acute leukemia.

Cytological identification of blasts in cerebrospinal fluid in acute leukemia, lymphoid or myeloid, in adult and child, at diagnosis or during follow up lead to the diagnosis of leukemic meningitidis. Suitable CNS therapy based on a defined "CNS status" following an international standardized classification, lead to decrease cerebrospinal relapses. Established in 1993, this classification allows to treat patients based on their CNS status. Based on the red blood cells count, nucleated cells count and presence of blasts, it requires a standard technical procedure that guarantees the comparability of results coming from different medical laboratory. To improve the quality of cerebrospinal fluid analysis, in acute leukemias, preanalytical guidelines (turn around time), analytical guidelines (cytocentrifugation, adding serum protein, speed and duration of cytocentrifugation) and postanalytical guidelines (duration of conservation) are set by the Groupe francophone d'hématologie cellulaire.