Color Atlas of Hematology - Practical Microscopic and Clinical ...

188Cytology of Organ Biopsies and ExudateCytology of Cerebrospinal FluidThe first step in all hemato-oncological and neurological diagnosticassessments of cerebrospinal fluid is the quantitative and qualitativeanalysis of the cell composition (Table 32).Table 32 Emergency diagnostics of the liquor (according to Felgenhauer in Thomas 1998)➤ Pandy’s reaction➤ Cell count (Fuchs-Rosenthal chamber)➤ Smear (or cytocentrifuge preparation)– to analyze the cell differentiation and– to search for bacteria and roughly determine their types and prevalence➤ Gram stain➤ An additional determination of bacterial antigens may be doneUsing advanced cell diagnostic methods, lymphocyte subpopulationscan be identified by immunocytology and marker analysis and cytogenetictests carried out on tumor cells.Prevalence of neutrophilic granulocytes with strong pleocytosis suggestsbacterial meningitis; often the bacteria can be directly characterized.Prevalence of lymphatic cells with moderate pleocytosis suggests viralmeningitis. (If clinical and serological findings leave doubts, the differentialdiagnosis must rule out lymphoma using immunocytologicalmethods.)Strong eosinophilia suggests parasite infection (e.g., cysticercosis).A complete mixture of cells with granulocytes, lymphocytes, and monocytesin equal proportion is found in tuberculous meningitis.Variable blasts, usually with significant pleocytosis, predominate inleukemic or lymphomatous meningitis.Undefinable cells with large nuclei suggest tumor cells in general, e.g.,meningeal involvement in breast cancer or bronchial carcinoma, etc. Thecell types are determined on the basis of knowledge of the primary tumorand/or by marker analysis. Among primary brain tumors, the most likelycells to be found in cerebrospinal fluid are those from ependymoma,pinealoma, and medulloblastoma.Erythrophages and siderophages (siderophores) are monocytes/macrophages,which take up erythrocytes and iron-containing pigment duringsubarachnoid hemorrhage.The cytological analysis of the cerebrospinal fluid offers important cluesto the character of meningeal inflammation, the presence of a malignancy,or hemorrhage.