2024 ICD-10-CM Diagnosis Code A83.5

by

California encephalitis

  • A83.5 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2024 edition of ICD-10-CM A83.5 became effective on October 1, 2023.
  • This is the American ICD-10-CM version of A83.5 – other international versions of ICD-10 A83.5 may differ.

Applicable To

  • California meningoencephalitis
  • La Crosse encephalitis

The following code(s) above A83.5 contain annotation back-references

 that may be applicable to A83.5:

  • A00-B99  Certain infectious and parasitic diseases
  • A80-A89  Viral and prion infections of the central nervous system
  • A83  Mosquito-borne viral encephalitis

Approximate Synonyms

  • La crosse encephalitis
  • La crosse virus encephalitis

Clinical Information

  • A viral infection of the brain caused by serotypes of california encephalitis virus (encephalitis virus, california) transmitted to humans by the mosquito aedes triseriatus. The majority of cases are caused by the la crosse virus. This condition is endemic to the midwestern United States and primarily affects children between 5-10 years of age. Clinical manifestations include fever; vomiting; headache; and abdominal pain followed by seizures, altered mentation, and focal neurologic deficits. (from Joynt, Clinical Neurology, 1996, ch26, p13)

ICD-10-CM A83.5 is grouped within Diagnostic Related Group(s) (MS-DRG v41.0):

  • 023 Craniotomy with major device implant or acute complex cns principal diagnosis with mcc or chemotherapy implant or epilepsy with neurostimulator
  • 024 Craniotomy with major device implant or acute complex cns principal diagnosis without mcc
  • 097 Non-bacterial infection of nervous system except viral meningitis with mcc
  • 098 Non-bacterial infection of nervous system except viral meningitis with cc
  • 099 Non-bacterial infection of nervous system except viral meningitis without cc/mcc

Convert A83.5 to ICD-9-CMCode History

  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change
  • 2021 (effective 10/1/2020): No change
  • 2022 (effective 10/1/2021): No change
  • 2023 (effective 10/1/2022): No change
  • 2024 (effective 10/1/2023): No change

Diagnosis Index entries containing back-references to A83.5: