2026 ICD-10-CM Diagnosis Code B81.3Intestinal angiostrongyliasis
ICD-10-CM Codes›A00–B99›B65-B83›B81
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Not Chronic
B81.3 is a billable ICD-10-CM diagnosis code for intestinal angiostrongyliasis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 391 through 392. 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 23 closely related codes. Coders also document this condition as infection by Angiostrongylus. 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.
- Infection by Angiostrongylus
- Infection caused by Angiostrongylus costaricensis
- Intestinal angiostrongyliasis
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Angiostrongyliasis due to:
- Angiostrongylus costaricensis
- Parastrongylus costaricensis
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.
costaricensis B81.3
intestinal B81.3
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.
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Convert B81.3 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About B81.3Overview
What is the ICD-10 code for intestinal angiostrongyliasis?
The ICD-10-CM code for intestinal angiostrongyliasis is B81.3 (sometimes written as B813). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is B81.3 (Other intestinal helminthiases, not elsewhere classified) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report intestinal angiostrongyliasis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does B81.3 group to?
When intestinal angiostrongyliasis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 391, 392, with relative weights from 0.7796 to 1.2683 depending on complications. Higher weights mean higher Medicare reimbursement.
Is B81.3 a CC or MCC?
CMS lists B81.3 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 23 closely related codes in its exclusion list.
What is the ICD-9 equivalent of B81.3?
Under the General Equivalence Mappings, intestinal angiostrongyliasis converts to ICD-9-CM 127.7 (intest helminthiasis NEC). The mapping is approximate, so confirm the match fits the documentation.
