Composition of Cerebrospinal Fluid (CSF)

Chemical Composition

Cerebrospinal fluid (CSF) is a clear, colorless liquid surrounding the brain and spinal cord, playing a crucial role in cushioning and protecting the central nervous system (CNS). Its chemical composition is finely regulated to ensure proper neurological function.

Proteins

CSF contains a significantly lower concentration of proteins than plasma, primarily albumin, prealbumin, and globulins. The presence of abnormal proteins may indicate pathological conditions like meningitis or multiple sclerosis.

Glucose

Glucose in CSF is derived from blood plasma and is essential for brain metabolism. Normal CSF glucose levels range between 40-70 mg/dL. Decreased glucose levels may signal infections such as bacterial meningitis.

Electrolytes

Electrolytes in CSF include sodium, potassium, calcium, chloride, and magnesium. Their precise balance maintains neuronal excitability and osmotic regulation.

Clinical Significance

Alterations in CSF composition can indicate neuroinflammatory or infectious diseases. CSF analysis is performed through lumbar puncture to aid diagnosis of conditions such as meningitis, encephalitis, and neurodegenerative disorders.