Life-Threatening Conditions:

• CNS infections are life-threatening and require urgent evaluation and treatment in a critical care unit.
• Identifying CNS infections can be challenging due to similarities with non-infectious conditions.

Diagnostic Challenges:

• Diagnosis of infectious syndromes may take several days before a specific microorganism is identified, requiring the use of broad empiric therapy.
• Clinical, epidemiologic, and demographic clues are used to guide the selection of appropriate antimicrobials.

Microorganisms and Risk Factors:

• CNS infections can be caused by bacteria, fungi, viruses, protozoa, and prions, with varying risk based on host immune status, epidemiology, and acquisition site.
• The microbiology and pathophysiology differ based on the anatomic site of infection.

Major Syndromes:

• Major CNS syndromes include meningitis, brain abscess, encephalitis, and myelitis, which may occur in isolation or overlap.
• Localizing the site of infection is crucial for guiding the diagnostic evaluation and initiating empiric therapy.

Interdisciplinary Approach:

• An interdisciplinary approach involving critical care, infectious disease, and neurology is important for addressing diagnostic and treatment considerations.
• Colleagues from different specialties collaborate to manage potential complications.

Meningitis:

• Bacterial infections cause an acute meningitis syndrome, while viruses, fungi, or mycobacteria cause subacute meningitis syndrome.
• Approaches balance obtaining a precise microbiologic diagnosis versus instituting early antimicrobial therapy.

Anatomy and Pathophysiology:

• Bacterial meningitis is a pyogenic infection of the meninges and subarachnoid space with implications for therapy and medication movement.