2026 ICD-10-CM Diagnosis Code B52.9Plasmodium malariae malaria without complication
ICD-10-CM Codes›A00–B99›B50-B64›B52
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Not Chronic
B52.9 is a billable ICD-10-CM diagnosis code for plasmodium malariae malaria without complication. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 867 through 869. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 32 closely related codes. Coders also document this condition as intermittent fever. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Parasitic, other specified and unspecified infections.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Intermittent fever
- Malarial fever
- Malarial red blood cell inclusion
- Plasmodium malariae gametocyte in red cell
- Quartan fever
- Quartan malaria
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Plasmodium malariae malaria NOS
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor) R50.9
quartan (malaria) B52.9
malariae B52.9
malariae NEC B52.9
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Quartan Malaria
malaria resulting from infection by plasmodium malariae.
Patient EducationClinical
Malaria
Malaria is a serious disease caused by a parasite. You get it when an infected mosquito bites you. Malaria is a major cause of death worldwide, but it is almost wiped out in the United States. The disease is mostly a problem in developing countries with warm climates. If you travel to these countries, you are at risk.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert B52.9 to ICD-9-CMHistory
Code HistoryHistory
Questions About B52.9Overview
What is the ICD-10 code for plasmodium malariae malaria without complication?
The ICD-10-CM code for plasmodium malariae malaria without complication is B52.9 (sometimes written as B529). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is B52.9 (Plasmodium malariae malaria) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report plasmodium malariae malaria without complication on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does B52.9 group to?
When plasmodium malariae malaria without complication is the principal diagnosis on an inpatient stay, it groups to MS-DRG 867, 868, 869, with relative weights from 0.7297 to 2.0932 depending on complications. Higher weights mean higher Medicare reimbursement.
Is B52.9 a CC or MCC?
CMS lists B52.9 as a CC (complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 32 closely related codes in its exclusion list.
What is the ICD-9 equivalent of B52.9?
Under the General Equivalence Mappings, plasmodium malariae malaria without complication converts to ICD-9-CM 084.2 (quartan malaria) and 084.5 (mixed malaria). The mapping is approximate, so confirm the match fits the documentation.
