Meningitis

Overview

Meningitis is inflammation of the meninges surrounding the brain and spinal cord. Infectious causes are particularly important because bacterial meningitis may progress rapidly and can be life-threatening.

Causes include bacterial, viral, fungal, and other infectious or non-infectious processes.

Suspected bacterial meningitis requires urgent assessment and prompt treatment.

Clinical Features

Common manifestations include fever, headache, neck stiffness, photophobia, vomiting, and altered mental status.

Seizures, focal neurological deficits, reduced consciousness, or signs of systemic sepsis may occur in severe disease.

The classic triad is not present in every patient, so meningitis should not be excluded simply because one feature is absent.

Investigation

Lumbar puncture with cerebrospinal fluid analysis is central to the diagnostic evaluation when it can be performed safely.

CSF assessment may include cell count, protein, glucose, microbiological testing, and other studies depending on the suspected cause.

Brain imaging may be required before lumbar puncture in selected patients with features suggesting an increased risk of intracranial complications.

Investigations should never create an unnecessary delay in treatment when bacterial meningitis is strongly suspected.

Management

Initial management focuses on stabilization, appropriate antimicrobial therapy, and treatment of complications.

Empirical antibiotic treatment is guided by age, immune status, local resistance patterns, and the suspected pathogen profile.

Additional therapy may be considered according to the clinical context, while supportive management addresses seizures, shock, raised intracranial pressure, and other complications.

In suspected bacterial meningitis, antimicrobial treatment should not be unnecessarily delayed while waiting for diagnostic procedures.

Complications

Complications may include seizures, hearing impairment, focal neurological deficits, hydrocephalus, cerebral injury, septic shock, and death.

Long-term neurological consequences depend on the severity of the infection and the underlying organism.

Clinical Pearls