ICD-10-CM 2027 diagnosis code
B51.8Plasmodium vivax malaria with other complications
B51.8 is a valid, billable ICD-10-CM code for plasmodium vivax malaria with other complications. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About B51.8
B51.8 is the ICD-10-CM diagnosis code for Plasmodium vivax malaria with other complications. It belongs to category B51 (Plasmodium vivax malaria), block B50-B64 (protozoal diseases) and chapter 1 (certain infectious and parasitic diseases). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within B51, choose B51.8 (with other complications) only when documentation doesn't support a more specific option: with rupture of spleen (B51.0) and without complication (B51.9).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 867 (Other Infectious and Parasitic Diseases Diagnoses with MCC, relative weight 2.1859), DRG 868 (Other Infectious and Parasitic Diseases Diagnoses with CC, relative weight 1.0235) and DRG 869 (Other Infectious and Parasitic Diseases Diagnoses without CC/MCC, relative weight 0.6787), in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as 084.9 (other pernicious complications of malaria).
Notes that apply from higher levels
Instructions written at a parent level also apply to B51.8.
› From B51 Plasmodium vivax malaria
- mixed infections of Plasmodium vivax with other Plasmodium species, except Plasmodium falciparum
- plasmodium vivax with Plasmodium falciparum (B50.-)
Broader instructions also apply from B50-B64 Protozoal diseases and Chapter 1: Certain infectious and parasitic diseases.
Alphabetic index entries
1 entriesTerms in the official ICD-10-CM index that lead to B51.8.
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 18 · Infectious and Parasitic Diseases, Systemic or Unspecified Sites
ICD-9-CM equivalent
Converter →- 084.9Other pernicious complications of malariaapproximate
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about B51.8
Is B51.8 billable?
- Yes. B51.8 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can B51.8 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict B51.8 as a principal diagnosis.
Is B51.8 a CC or MCC?
- B51.8 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.
What DRG does B51.8 group to?
- B51.8 is used in the MS-DRG v44.0 logic for MS-DRG 867 (Other Infectious and Parasitic Diseases Diagnoses with MCC), MS-DRG 868 (Other Infectious and Parasitic Diseases Diagnoses with CC) and MS-DRG 869 (Other Infectious and Parasitic Diseases Diagnoses without CC/MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
What is the ICD-9 code for B51.8?
- The CMS General Equivalence Mappings map B51.8 to ICD-9-CM 084.9.