A44.0 ICD-10-CM Code: Systemic bartonellosis
HCC Buddy Code Card
Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.
FY 2026 Apr update / Certain infectious and parasitic diseases (A00-B99) / Other bacterial diseases (A30-A49)
A44.0
Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidanceSystemic bartonellosis
Systemic bartonellosis is a serious infection caused by Bartonella bacteria that affects multiple organ systems in the body. This condition can cause fever, fatigue, and damage to various organs if left untreated.
CMS-HCC V28
N/A—
Not mapped
CMS-HCC V24
N/A—
Not mapped
ACA/HHS
N/A—
Not mapped
ESRD/PACE
N/A—
Not mapped
RXHCC
N/A—
Not mapped
Code Book Path
Inclusion Terms
Official- Oroya fever
Excludes 2
OfficialICD-10-CM does not list Excludes 2 notes for A44.0 in this effective period.
Related Child Codes
Includes
OfficialICD-10-CM does not list Includes notes for A44.0 in this effective period.
Excludes 1
OfficialICD-10-CM does not list Excludes 1 notes for A44.0 in this effective period.
Code First
OfficialICD-10-CM does not list Code First sequencing instructions for A44.0 in this effective period.
Use Additional
OfficialICD-10-CM does not list Use Additional Code instructions for A44.0 in this effective period.
Code Also
OfficialICD-10-CM does not list Code Also instructions for A44.0 in this effective period.
Buddy Documentation Tip
Current with CMS: FY2026 ICD-10-CM Apr 1 update (effective Apr 1 – Sep 30, 2026) · CMS-HCC V28, 100% phased in for payment year 2026. FY2027 code set already staged for October 1, 2026. How HCC Buddy stays current →
Is A44.0 an HCC code?
No. A44.0 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.
- Code
- A44.0
- Description
- Systemic bartonellosis
- HCC (V28)
- No CMS-HCC V28 mapping
- RAF
- —
- Billable
- Yes
- Payment year
- 2026
Coder workflow notes
Get the V28 RAF + MEAT cheat sheet
One printable page: confirm a code's V28 HCC status, its RAF weight, and the MEAT your note needs to make it stick. Free, no card.
Free PDF. No card. Unsubscribe anytime.
This code does not map to an HCC category in any model (V28, V24, ESRD, RxHCC).
What This Code Means
A44.0 is the ICD-10-CM diagnosis code for systemic bartonellosis. Systemic bartonellosis is a serious infection caused by Bartonella bacteria that affects multiple organ systems in the body. This condition can cause fever, fatigue, and damage to various organs if left untreated. A44.0 sits in the ICD-10-CM chapter for certain infectious and parasitic diseases (a00-b99), within the section covering other bacterial diseases (a30-a49).
A44.0 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.
Verify the specific type of Bartonella organism involved (B. bacilliformis, B. henselae, etc.) as some may have more specific codes available.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for A44.0 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Verify the specific type of Bartonella organism involved (B. bacilliformis, B. henselae, etc.) as some may have more specific codes available
- •Document whether this is a primary infection or a complication of another condition, and check for any associated manifestations (endocarditis, angiomatosis) that may require additional codes