[Abnormal cytological findings in cerebrospinal fluid with normal cell count (author's transl)]

A qualitative cytological study demonstrated that normal cell count in the cerebrospinal fluid does not exclude abnormal cytological findings. Siderophages were found as a late indicator of haemorrhage into the CSF. In some cases of tumours of the CNS sporadic atypical cells were found without other alterations in CSF findings. Granulocytes or macrophages were found in vascular diseases, in response to trauma, in tumours and after inflammation of the meninges as an indicator of persistent minimal inflammatory activity. Two cases of Heredopathia atactica polyneuritiformis (Refsum's syndrome) showed characteristic vacuolar macrophages in the CSF (described for the first time), in spite of a normal cell count. The findings point to the diagnostic values of qualitative cytological analysis even in cerebrospinal fluid specimens with a normal cell count. The importance of adapting the cytological method for routine laboratory procedure is stressed.