ICD-10 A48.3
Billable / Specific HCC v28: 2 MCCToxic shock syndrome
About ICD-10-CM A48.3
ICD-10-CM code A48.3 represents Toxic shock syndrome. This is a billable/specific code in the Infectious and Parasitic Diseases chapter (block A48). The 2026 edition of ICD-10-CM A48.3 became effective on October 1, 2025.
Coding Tips for A48.3
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
A48.3 is a CMS-HCC v28 risk-adjustment code (category 2). To count for the patient Risk Adjustment Factor (RAF), document the diagnosis with MEAT language each calendar year: Monitored, Evaluated, Assessed, Treated. A diagnosis on the problem list alone does not satisfy CMS RADV audit standards. Include the diagnosis in the assessment with current status and current treatment plan.
A48.3 is designated MCC for MS-DRG grouping. On inpatient claims, this code can shift the DRG to the with-MCC variant when documented as a present-on-admission secondary diagnosis. Hospital CDI programs flag MCC opportunities during chart review. Failure to capture this code may leave 30 to 80 percent of the inpatient stay revenue unrealized.
Type 1 Excludes
Pure excludes, these codes can never be coded together with A48.3. The conditions are mutually exclusive (e.g., congenital vs acquired forms).
- endotoxic shock NOS (R57.8)
- sepsis NOS (A41.9)
Use Additional Code
When coding A48.3, also report these additional codes when applicable.
- code to identify the organism (B95, B96)
Medicare Advantage HCC Impact
Capture this diagnosis annually for accurate risk adjustment. Missed HCC captures are the #1 revenue leak in Medicare Advantage risk programs.
Inpatient DRG Impact, MCC
codes Toxic shock syndrome. As a Major Complication/Comorbidity (MCC), this can shift the DRG assignment to a higher-weighted category, substantial reimbursement impact.
Medicare LCD Coverage for A48.3
Local Coverage Determinations (LCDs) from CMS MACs that list A48.3 as a covered diagnosis.
Showing top 10 of 25 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing A48.3.
2 Medicare
1 Aetna
CPT Codes Commonly Billed with A48.3
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
We don't have CPT pairings indexed for this specific code yet. Use the CPT search above to find common procedures, or check your payer's published medical policy for code-specific guidance.
Convert A48.3 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| A48.3 | 04082 | 00000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To A48.3
Other codes in section A30-A49 (Other bacterial diseases).
ICD-10 A48.3, Billing FAQ
Is ICD-10 code A48.3 billable? +
Yes, A48.3 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What codes are Type 1 Excludes for A48.3? +
Type 1 Excludes (never code together with A48.3): endotoxic shock NOS (R57.8); sepsis NOS (A41.9)
Does A48.3 affect Medicare Advantage HCC risk adjustment? +
Yes. A48.3 maps to CMS-HCC v28 category 2. Capture this diagnosis annually for accurate Medicare Advantage risk score.
Is A48.3 a CC or MCC for inpatient DRG? +
Yes, this code is designated as MCC. Documenting as a secondary diagnosis on inpatient claims can shift the DRG to a higher-weighted category.
What ICD-9 codes does A48.3 map to? +
Per CMS GEMs, A48.3 maps to ICD-9 codes: 04082. Useful for legacy data review and historical claim analysis.
Get the full PayerReady toolkit
Free access to CPT/ICD-10 lookup, denial appeals, fee comparator, and claim auditing with credentialing enrollment.
Start free →Run this code through our claim audit tool
Check NCCI bundling, MUE limits, and modifier logic before submission.
Try the auditor →Did this page help?
Quick signal so we know what to improve.
If you want a code reference page that doesn't exist yet, email coding@payerready.com.
Tell us what's missing or wrong: coding@payerready.com. We respond within 5 business days.
Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on May 31, 2026.
Powered by 11K CPT · 98K ICD-10 · 860K MPFS rates · 4.5M NCCI edits · 9.5M NPIs. Our data methodology · About our coding team