Table 2. . Comparison of typical findings for common cerebrospinal fluid laboratory tests by etiology of meningitis.
| Meningitis Etiology | Total Protein | CSF/blood glucose ratio | Total WBC | Predominant WBC type |
|---|---|---|---|---|
| Bacterial | +++ | +++ | +++ | Neutrophils |
| Aseptic (Viral) | ± | ± | ± | Lymphocytes† |
| Tuberculosis | ++ | +++ | ++ | Lymphocytes |
| Cryptococcal | ++ | ++ | ± | Lymphocytes |
| Coccidioidal | ++ | + | ± | Lymphocytes‡ |
| Blastomyces | ++ | ++ | ± | Lymphocytes |
| Histoplasma | ++ | ++ | ± | Lymphocytes |
| Aspergillus | ++ | + | ± | Lymphocytes |
May be neutrophil predominant early in the disease course.
Eosinophilic predominance occurs less commonly but when seen is highly suggestive.
The number of + signs indicate proportional gradient of increase (total protein or total WBC) or decease (ratio of CSF/blood glucose) of the lab test. To indicate proportionally minimal or no increase/decrease, ± is used. WBC differential indicates the dominant cell type present although other cells generally are present as well.
CSF: Cerebrospinal fluid; WBC: White blood cell.