Laboratory parameters of the 1st order – obligatory laboratory tests.
- Small blood count
- Differential blood count
- Inflammatory parameters – CRP (C-reactive protein) or PCT (procalcitonin).
- Fasting glucose (fasting blood glucose).
- Coagulation parameters – PTT, Quick
- Blood cultures (two) – collection of blood into special collection systems (blood culture bottles), in which the bacteria that may be in the blood can grow and thus be determined.
- Cerebrospinal fluid (CSF) puncture (lumbar puncture/collection of cerebrospinal fluid by puncture of the spinal canal) for CSF diagnosis:Note: If there is no neurological deficit, decrease in vigilance or epileptic seizure, the CSF puncture is performed immediately, followed by cranial computed tomography (cCT).
- CSF diagnostics: total protein, albumin, glucose, IgG, oligoclonal immunoglobulins, lactate; bacterial meningitis:
- Color: cloudy aspect
- Pressure > 20 cm H2O
- Cell count > 1,000 109/l (> 70 % granulocytes)
- Glucose < 40 % of the serum value
- Lactate < 3.5 mmol/l
- Protein > 0.45 g/l
- Detection of microorganisms in the direct preparation: 80% of cases.
- Bacteriology (microscopic and cultural): cerebrospinal fluid, blood cultures for pathogens and resistance and for immediate microscopic evaluation (if necessary, also for mycobacteria). [bacterial meningitis: positive blood cultures 50-90%]
- Meningococcal rapid test
- Pathogen detection by PCR (polymerase chain reaction).
- Antigen detection: CSF for agglutination with antisera against Haemophilus influencae Tyb B, Neisseria meningitidis (A,B,C), Streptococcus pneumoniae.
- CSF diagnostics: total protein, albumin, glucose, IgG, oligoclonal immunoglobulins, lactate; bacterial meningitis:
- For abacterial meningitis
- Serology: antibodies against Borrelia, CMV, EBV, TBE virus, herpes simplex virus, measles virus, mumps virus, varicella zoster virus, Treponema pallidum.
Note: In acute bacterial meningitis disease, microscopic or cultural detection of the pathogen from a CSF sample is not always successful (esp. with antibiotic pretreatment).
Direct detection of the pathogen Neisseria meningitidis is notifiable according to the Infection Protection Act (IfSG). Notification is only mandatory for direct detection from cerebrospinal fluid, blood, hemorrhagic skin infiltrates, or other normally sterile substrates.
