2027 ICD-10-CM Diagnosis Code B64Unspecified protozoal disease
ICD-10-CM Codes›A00–B99›B50-B64›B64
- Billable — Valid for Submission
- Not Chronic
B64 is a billable ICD-10-CM diagnosis code for unspecified protozoal disease. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 867 through 869. 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.
- Cardiovascular abnormality due to infective myocarditis
- Dilated cardiomyopathy due to infectious disease
- Dilated cardiomyopathy due to parasitic myocarditis
- Dilated cardiomyopathy due to protozoan myocarditis
- Encephalitis caused by protozoa
- Infective ulcer of esophagus
- Parasitic conjunctivitis
- Parasitic disease in mother complicating pregnancy, childbirth AND/OR puerperium
- Parasitic infection causing ulcer of esophagus
- Parasitic infection of lacrimal gland
- Parasitic myocarditis
- Parasitic myositis
- Protozoal conjunctivitis
- Protozoal corneal ulcer
- Protozoal dacryoadenitis
- Protozoal disease complicating pregnancy childbirth and the puerperium
- Protozoal esophagitis
- Protozoal infestation of skin
- Protozoal myelitis
- Protozoal myositis
- Protozoal ulcer of esophagus
- Protozoan infection
- Protozoan myocarditis
- Recurrent infection caused by Protozoa
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to B64: its own notes plus those printed at block B50-B64 and Chapter 1. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- diseases generally recognized as communicable or transmissible
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- carrier or suspected carrier of infectious disease (Z22.-)
- certain localized infections - see body system-related chapters
- infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
- infectious and parasitic diseases specific to the perinatal period (P35-P39)
- influenza and other acute respiratory infections (J00-J22)
Use Additional Code
Add a second code, after this one, to fully describe the condition.
- code to identify resistance to antimicrobial drugs (Z16.-)
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name B64, its category, or a range that includes it.
Applicable To 1
These notes mention B64.
- O98.6 Protozoal diseases complicating pregnancy, childbirth and the puerperium
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Disease, diseased See Also: Syndrome;
protozoal B64
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Parasitic Diseases
Parasites are living things that use other living things - like your body - for food and a place to live. You can get them from contaminated food or water, a bug bite, or sexual contact. Some parasitic diseases are easily treated and some are not.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert B64 to ICD-9-CMHistory
Code HistoryHistory
Questions About B64Overview
What is the ICD-10 code for unspecified protozoal disease?
The ICD-10-CM code for unspecified protozoal disease is B64. It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is B64 (Unspecified protozoal disease) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unspecified protozoal disease on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does B64 group to?
When unspecified protozoal disease is the principal diagnosis on an inpatient stay, it groups to MS-DRG 867, 869, 868, with relative weights from 0.6784 to 2.1855 depending on complications. Higher weights mean higher Medicare reimbursement.
Can B64 be reported with a code from A06?
Not as a rule. The Excludes1 note at block B50-B64, which applies to B64, lists "amebiasis (A06.-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).
What is the ICD-9 equivalent of B64?
Under the General Equivalence Mappings, unspecified protozoal disease converts to ICD-9-CM 088.9 (arthropod-borne dis NOS) and 136.9 (infect/parasite dis NOS). The mapping is approximate, so confirm the match fits the documentation.
