Background
- Inflammation or infection of the meninges and subarachnoid spact
- May be acute, subacute, or chronic (≥4 weeks)
- May be caused by bacteria, viruses, fungi, parasites, or non-infectious causes
Diagnosis
- Typically confirmed by lumbar puncture demonstrating pleocytosis, with or without MRI brain
| Parameter | Normal | Bacterial | Viral | Tuberculous | Fungal |
|---|---|---|---|---|---|
| Opening pressure | 12 to 20 cmH2O | raised | normal or raised | raised | raised |
| Appearance | clear | cloudy | clear | clear or cloudy | clear or cloudy |
| WBC count | <5 | >100 | 5 to 100 | 5 to 500 | 5 to 500 |
| Differential | PMN | lymphocyte | lymphocyte | lymphocyte | |
| Protein | 0.4 g/L | high | somewhat high | very high | high |
| Glucose | >2/3 of plasma | very low | normal to low | very low | low |
