Abnormal microbiological findings in cerebrospinal fluid

This code signifies the presence of unusual or pathogenic microorganisms identified through laboratory analysis of cerebrospinal fluid (CSF). It indicates an abnormal finding suggesting an infection or other pathological process affecting the central nervous system.

Use this code when laboratory reports confirm the isolation or detection of bacteria, fungi, viruses, or other microbes in a CSF sample, and the patient does not yet have a definitive diagnosis for a specific CNS infection. Documentation should clearly state "abnormal microbiological findings in CSF" or specify the presence of microorganisms without a confirmed infectious disease code.

• Do not use this code if a definitive diagnosis of a specific CNS infection (e.g., bacterial meningitis, viral encephalitis) is established; instead, code the specific infection.
• This code is for abnormal findings only; do not use for normal CSF culture results.
• Remember the Excludes1 note: never code this with colonization status (Z22.-).