ICD10BillableValid for clinical use
ICD-10 Code A43.9: Nocardiosis, unspecified
Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026
What is this code?
ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Certain infectious and parasitic diseases (A00-B99).
When is it used?
- May be used when a clinician documents nocardiosis, unspecified in a patient's medical record.
- May appear in hospital records, claims, referrals, and clinical documentation.
- This code can be used as a clinically usable diagnosis entry in standardized coding workflows.
What it does not mean
- A code alone does not explain severity, treatment plan, or outcome.
- A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
Code hierarchy
chapter
1Certain infectious and parasitic diseases (A00-B99)
block
A30-A49Other bacterial diseases
category
A43Nocardiosis
currentA43
Where you may see this code
You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.
Related specialists
Infectious Disease SpecialistGeneral Physician
Related codes
Sibling codes
Mapped diagnoses and classifications
SNOMED_CT 240443003high
Disseminated nocardiosis
Source: SNOMED International ICD-10 map
SNOMED_CT 713545009high
Infection caused by Nocardia co-occurrent with human immunodeficiency virus infection
Source: SNOMED International ICD-10 map
SNOMED_CT 29227009high
Nocardiosis
Source: SNOMED International ICD-10 map
SNOMED_CT 421431004high
Nocardiosis with AIDS (acquired immunodeficiency syndrome)
Source: SNOMED International ICD-10 map
Coding guidelines
Compatibility
Legacy and official ICD code match exactly.
Legacy codes
A43.9
Common synonyms
Nocardiosis, unspecifiedNocardiosis
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.