Specific code 2006 ICD-9-CM Diagnosis Code 323.9
Unspecified cause of encephalitis
  • Short description: ENCEPHALITIS NOS.
  • ICD-9-CM 323.9 is a billable medical code that can be used to indicate a diagnosis on a reimbursement claim, however, 323.9 should only be used for claims with a date of service on or before September 30, 2015. For claims with a date of service on or after October 1, 2015, use an equivalent ICD-10-CM code (or codes).
  • You are viewing the 2006 version of ICD-9-CM 323.9.
  • More recent version(s) of ICD-9-CM 323.9: 2007 2008 2009 2010 2011 2012 2013 2014 2015.
Convert to ICD-10-CM: 323.9 converts approximately to:
  • 2015/16 ICD-10-CM G04.90 Encephalitis and encephalomyelitis, unspecified
    Or:
  • 2015/16 ICD-10-CM G04.91 Myelitis, unspecified
Approximate Synonyms
  • Acute and subacute hemorrhagic leukoencephalitis [Hurst]
  • Acute ascending myelitis
  • Acute hemorrhagic encephalomyelitis
  • Acute hemorrhagic leukoencephalitis
  • Acute necrotizing myelitis
  • Acute non-infective transverse myelitis
  • Acute transverse myelitis
  • Acute viral transverse myelitis
  • Brainstem encephalitis
  • Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy
  • Cerebral irritation
  • Encephalitis
  • Encephalitis associated with AIDS
  • Encephalitis, limbic
  • Encephalitis, myelitis and encephalomyelitis
  • Encephalomyelitis
  • Encephalomyelitis, hemorrhagic, acute
  • Focal encephalitis
  • Fungal infection of brain
  • Granulomatous meningoencephalitis
  • Granulomatous meningoencephalomyelitis
  • Inflammation of spinal cord due to toxin
  • Leukoencephalopathy
  • Leukoencephalopathy, subcortical
  • Limbic encephalitis
  • Meningoencephalitis
  • Meningoencephalomyelitis
  • Meningomyelitis
  • Myelitis
  • Myelitis associated with AIDS
  • Necrotizing myelitis of CNS, subacute
  • Primary encephalitis
  • Rasmussen syndrome
  • Subacute hemorrhagic leukoencephalitis
  • Subacute necrotizing myelitis
  • Subacute necrotizing myelitis of CNS
  • Subcortical leukoencephalopathy
  • Transverse myelopathy syndrome
ICD-9-CM Volume 2 Index entries containing back-references to 323.9:
  • Encephalitis (bacterial) (chronic) (hemorrhagic) (idiopathic) (nonepidemic) (spurious) (subacute) 323.9
    • acute - see also Encephalitis, viral
    • arboviral, arbovirus NEC 064
    • arthropod-borne (see also Encephalitis, viral, arthropod-borne) 064
    • Dawson's (inclusion body) 046.2
    • following vaccination or other immunization procedure 323.5
    • infectious (acute) (virus) NEC 049.8
    • late effect - see Late, effect, encephalitis
    • lethargic (acute) (infectious) (influenzal) 049.8
    • Negishi virus 064
    • periaxialis (concentrica) (diffusa) 341.1
    • postvaccinal (smallpox) 323.5
    • progressive subcortical (Binswanger's) 290.12
    • Russian
    • slow-acting virus NEC 046.8
    • specified cause NEC 323.8
    • subacute sclerosing 046.2
    • Trypanosomiasis (see also Trypanosomiasis) 086.9 [323.2]
    • tuberculous (see also Tuberculosis) 013.6
  • Encephalomyelitis (chronic) (granulomatous) (hemorrhagic necrotizing, acute) (myalgic, benign) (see also Encephalitis) 323.9
    • abortive disseminated 049.8
    • due to or resulting from vaccination (any) 323.5
    • funicularis infectiosa 049.8
    • late effect - see Late, effect, encephalitis
    • postvaccinal (smallpox) 323.5
    • specified cause NEC 323.8
  • Fever 780.6
    • brain 323.9
      • late effect - see category 326
    • cerebral 323.9
      • late effect - see category 326
  • Hematomyelitis 323.9
    • late effect - see category 326
  • Infection, infected, infective (opportunistic) 136.9
    • brain (see also Encephalitis) 323.9
      • late effect - see category 326
      • membranes - (see also Meningitis) 322.9
      • septic 324.0
        • late effect - see category 326
        • meninges (see also Meningitis) 320.9
    • spinal cord NEC (see also Encephalitis) 323.9
      • abscess 324.1
        • late effect - see category 326
      • late effect - see category 326
      • meninges - see Meningitis
      • streptococcal 320.2
  • Inflammation, inflamed, inflammatory (with exudation)
    • brain (see also Encephalitis) 323.9
      • late effect - see category 326
      • membrane - see Meningitis
    • cerebral (see also Encephalitis) 323.9
      • late effect - see category 326
      • membrane - see Meningitis
    • spinal
      • cord (see also Encephalitis) 323.9
        • late effect - see category 326
      • membrane - see Meningitis
      • nerve - see Disorder, nerve
  • Leukoencephalopathy (see also Encephalitis) 323.9
    • acute necrotizing hemorrhagic (postinfectious) 136.9 [323.6]
      • postimmunization or postvaccinal 323.5
    • multifocal (progressive) 046.3
    • progressive multifocal 046.3
  • Meningoencephalitis (see also Encephalitis) 323.9
    • bacterial, purulent, pyogenic, or septic - see Meningitis
    • infectious (acute) 048
    • late effect - see category 326
    • lymphocytic (serous) 049.0
    • toxoplasmosis (acquired) 130.0
    • tuberculous (see also Tuberculosis, meninges) 013.0
  • Meningoencephalomyelitis (see also Meningoencephalitis) 323.9
    • acute NEC 048
      • disseminated (postinfectious) 136.9 [323.6]
        • postimmunization or postvaccination 323.5
    • late effect - see category 326
  • Meningomyelitis (see also Meningoencephalitis) 323.9
    • blastomycotic NEC (see also Blastomycosis) 116.0 [323.4]
    • late effect - see category 326
    • tuberculous (see also Tuberculosis, meninges) 013.0
  • Mesencephalitis (see also Encephalitis) 323.9
    • late effect - see category 326
  • Myelitis (acute) (ascending) (cerebellar) (childhood) (chronic) (descending) (diffuse) (disseminated) (pressure) (progressive) (spinal cord) (subacute) (transverse) (see also Encephalitis) 323.9
    • late effect - see category 326
    • syphilitic (transverse) 094.89
    • tuberculous (see also Tuberculosis) 013.6
  • Myelopathy (spinal cord) 336.9
    • transverse (see also Encephalitis) 323.9
  • Parencephalitis (see also Encephalitis) 323.9
    • late effect - see category 326
  • Phrenitis 323.9
  • Syringomyelitis 323.9
    • late effect - see category 326
ICD-9-CM codes are used in medical billing and coding to describe diseases, injuries, symptoms and conditions. ICD-9-CM 323.9 is one of thousands of ICD-9-CM codes used in healthcare. Although ICD-9-CM and CPT codes are largely numeric, they differ in that CPT codes describe medical procedures and services. Can't find a code? Start at the root of ICD-9-CM, check the 2006 ICD-9-CM Index or use the search engine at the top of this page to lookup any code.