B45.1

HCC Category Mapping

What This Code Means

A serious fungal infection of the brain caused by Cryptococcus, a fungus found in soil and bird droppings. This condition can cause inflammation of the brain and its protective membranes, leading to symptoms like headache, fever, and confusion.

Coding Tips

• •Cerebral cryptococcosis is typically associated with immunocompromised patients (HIV/AIDS, organ transplant recipients); verify if an underlying immunodeficiency condition is documented and coded separately
• •Ensure the documentation specifies 'cerebral' or 'CNS' involvement, as cryptococcosis can affect other sites (pulmonary, disseminated) and requires different codes

Clinical Significance

Cerebral cryptococcosis (cryptococcal meningitis/meningoencephalitis) is one of the most common AIDS-defining infections worldwide and carries significant mortality even with treatment. It is the leading cause of meningitis in sub-Saharan Africa and represents a critical diagnosis requiring emergent antifungal therapy and intracranial pressure management.

Documentation Requirements

• ✓Positive cerebrospinal fluid cryptococcal antigen or India ink preparation
• ✓Cerebrospinal fluid findings: elevated opening pressure, low glucose, elevated protein, lymphocytic pleocytosis
• ✓Neurologic symptoms documented: headache, altered mental status, cranial nerve palsies, neck stiffness
• ✓HIV status and CD4 count documented (typically <100 cells/microL)
• ✓Treatment regimen: induction (amphotericin B + flucytosine), consolidation, maintenance phases

Commonly Confused Codes