B95.62

🧬 ICD-10 CM B95.62 — Methicillin Resistant Staphylococcus Aureus Infection as the Cause of Diseases Classified Elsewhere

Billable Code Confirmed

ICD-10 CM B95.62 is a valid, billable 6-character ICD-10-CM code effective for FY2026. It is classified under Chapter 1 (Certain Infectious and Parasitic Diseases) within the B95-B97 block covering bacterial and viral infectious agents. This code is always assigned as a secondary code to identify MRSA as the causative organism of an infection whose site or type is reported with a separate principal diagnosis code. The 6-character specificity confirms the methicillin-resistant variant of Staphylococcus aureus, distinguishing it from the susceptible strain coded at B95.61.

Non-Billable Parent Codes

• B95 (Streptococcus, Staphylococcus, and Enterococcus as the cause of diseases classified elsewhere) — Non-billable header; lacks specificity about organism type and resistance pattern.
• B95.6 (Staphylococcus aureus as the cause of diseases classified elsewhere) — Non-billable subcategory; does not specify methicillin resistance status, which is required for accurate antimicrobial stewardship and reimbursement.

Clinical Context

ICD-10 CM B95.62 is used specifically when a provider documents an active MRSA infection at a known site (e.g., wound, UTI, cellulitis) and no combination code exists that captures both the condition and the MRSA organism. Per ICD-10-CM Official Guideline I.C.1.e, in this situation, you report the infection site code first, then add B95.62 to identify the resistant organism. This distinction is critical: when a combination code does exist (e.g., A41.02 for MRSA sepsis, J15.212 for MRSA pneumonia), B95.62 is never added — the combination code alone captures both elements. Accurate use of this code supports antibiotic stewardship documentation and signals clinical complexity to payers.

Code Classification

ICD-10 CM B95.62 is a diagnosis (etiology/supplementary) code within ICD-10-CM — it classifies an infectious agent, not a disease site. It is never a principal diagnosis and cannot stand alone; it must always be paired with the code for the infection it caused. It is not an ICD-10-PCS procedure code, a CPT code, or an HCC-driving standalone code.

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🔍 Code Description

ICD-10 CM B95.62 reports MRSA — Methicillin-resistant Staphylococcus aureus — as the causative organism of a separately coded infection. MRSA is a strain of S. aureus that has developed resistance to beta-lactam antibiotics, including methicillin, oxacillin, penicillin, and amoxicillin, due to the mecA gene encoding an altered penicillin-binding protein (PBP2a). This resistance pattern limits treatment options significantly, making MRSA infections more difficult and expensive to manage than those caused by methicillin-susceptible S. aureus (MSSA). The code belongs to the “bacterial agents” block (B95-B97), which is specifically designed as a supplementary classification — meaning these codes exist solely to identify the organism behind a disease reported elsewhere in the code set.

In inpatient coding, B95.62 is critical for capturing the full clinical picture of a patient’s infection. Common presentations requiring this code include MRSA wound infections, MRSA urinary tract infections, MRSA osteomyelitis, and MRSA cellulitis — all of which lack dedicated combination codes in ICD-10-CM. According to ICD-10-CM Official Guideline I.C.1.e, when documentation confirms a current MRSA infection at a known site and no combination code applies, coders are directed to assign the site-specific infection code as principal (or secondary as appropriate to sequencing rules) followed by B95.62. Failure to add B95.62 when documented underreports the clinical complexity and can result in lost CC/MCC capture, impacting MS-DRG reimbursement.

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🌳 Code Tree / Hierarchy

B95  Streptococcus, Staphylococcus, and Enterococcus as cause of diseases classified elsewhere ❌ Non-billable
│
├── B95.0  Streptococcus, group A, as cause of diseases classified elsewhere ✅ Billable
├── B95.1  Streptococcus, group B, as cause of diseases classified elsewhere ✅ Billable
├── B95.2  Enterococcus as cause of diseases classified elsewhere ✅ Billable
├── B95.3  Streptococcus pneumoniae as cause of diseases classified elsewhere ✅ Billable
│
├── B95.6  Staphylococcus aureus as cause of diseases classified elsewhere ❌ Non-billable
│   │
│   ├── B95.61  Methicillin susceptible Staphylococcus aureus (MSSA) infection as cause ✅ Billable
│   └── B95.62  Methicillin resistant Staphylococcus aureus (MRSA) infection as cause ◀ THIS CODE ✅ Billable
│
└── B95.8  Unspecified staphylococcus as cause of diseases classified elsewhere ✅ Billable

Specificity Matters: Resistant vs. Susceptible

Selecting B95.62 over B95.61 (MSSA) or B95.8 (unspecified staph) requires explicit provider documentation of methicillin resistance. If the documentation says “staph infection” without specifying resistance status, query the provider before defaulting — payer auditors look for this distinction and it directly impacts treatment coding, antimicrobial stewardship reporting, and case complexity capture.

Never Use B95.62 With Combination Codes

If the principal diagnosis is A41.02 (MRSA sepsis) or J15.212 (MRSA pneumonia), do not assign B95.62 in addition. These combination codes already fully describe both the condition and the MRSA organism. Adding B95.62 would be duplicative and is a common compliance audit finding per ICD-10-CM Official Guidelines I.C.1.e.

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✅ Includes

• MRSA wound infection (non-combination): When documentation states a wound infection, stitch abscess, or surgical site infection is due to MRSA and no combination code covers it — report the wound code first, then B95.62.
• MRSA urinary tract infection: When a UTI is documented as MRSA-caused, assign the UTI code (e.g., N39.0) as principal and B95.62 as an additional code to identify the resistant organism.
• MRSA osteomyelitis: Bone infections confirmed as MRSA-caused (e.g., M86.xx) are paired with B95.62 when no combination code applies.
• MRSA cellulitis/skin infections: MRSA-caused cellulitis or skin/soft tissue infections without a combination code require the appropriate L-code plus B95.62.
• MRSA bacteremia (non-sepsis): When bacteremia is documented due to MRSA but does not meet sepsis criteria, assign R78.81 (bacteremia) with B95.62.

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❌ Excludes

Excludes 1

These codes have a mutually exclusive relationship with B95.62 — when they apply, B95.62 must not be assigned:

• A41.02 — Sepsis due to Methicillin resistant Staphylococcus aureus: This is a combination code that fully captures both the MRSA organism and the sepsis condition. Assigning B95.62 alongside A41.02 would be duplicative and non-compliant with ICD-10-CM Official Guidelines I.C.1.e. If the patient has MRSA sepsis, use A41.02 only.
• J15.212 — Pneumonia due to Methicillin resistant Staphylococcus aureus: This combination code captures the MRSA etiology within the pneumonia code itself. Adding B95.62 is incorrect when J15.212 is assigned; the combination code is the complete and compliant code choice.

Most Common Excludes 1 Error

The most frequent audit-flagged error is assigning B95.62 alongside A41.02 or J15.212. Coders sometimes add B95.62 out of habit to “confirm” the MRSA organism, but these combination codes make it redundant and non-compliant. Always check for a combination code before adding B95.62 — this is one of the top MRSA coding compliance vulnerabilities per ICD-10-CM guidelines.

Excludes 2

These codes represent different clinical scenarios that can be reported alongside B95.62 when both are documented:

• Z22.322 — Carrier or suspected carrier of MRSA: This code covers MRSA colonization (patient carries MRSA on skin/nares but has no active infection). When a patient has both documented MRSA colonization AND an active MRSA infection at a separate site, both Z22.322 and the infection code + B95.62 may be assigned. Per ICD-10-CM guidelines, if only colonization is documented (no active infection), assign Z22.322 alone — not B95.62.

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📋 Clinical Overview

MRSA Infection vs. Colonization vs. Susceptible Staph

Distinguishing active MRSA infection, MRSA colonization, and MSSA infection is fundamental to correct code assignment. An active MRSA infection requires clinical signs and symptoms at the infection site with provider documentation of MRSA as the causative organism — typically confirmed by culture and sensitivity. Colonization means the organism is present (often in nares or on skin) but is not causing illness. The resistance pattern — MRSA vs. MSSA — must be explicitly documented; coders cannot assume resistance from clinical presentation alone.

Feature	B95.62	B95.61 (MSSA)	Z22.322 (MRSA Carrier)
Active infection required?	Yes — must have documented MRSA infection at known site	Yes — MSSA infection at known site	No — colonization without active infection
Code sequence	Always secondary; site-specific code is principal	Always secondary; site-specific code is principal	Can be principal or secondary depending on encounter
Antibiotic resistance	Resistant to methicillin/beta-lactams (mecA gene)	Susceptible to methicillin/penicillinase-resistant penicillins	Carrier state only — no active disease
Combination codes available	A41.02 (sepsis), J15.212 (pneumonia)	A41.01 (sepsis), J15.211 (pneumonia)	None — standalone carrier code
CDI query trigger	Yes — if resistance not specified in documentation	Yes — if resistance not specified	If admission note mentions nasal swab + no active infection dx

CDI Trigger — Resistance Documentation

If the record reflects an MRSA culture result in the microbiology report but the provider’s progress notes or discharge summary do not explicitly state the infection is due to MRSA, a CDI query is warranted. Coders cannot independently assign B95.62 based solely on lab results — the provider must clinically document the causal relationship between the MRSA organism and the condition being treated.

Manifestations & Symptom Burden

• Wound/Surgical Site Infection: MRSA is a leading cause of post-surgical wound infections; SSI due to MRSA substantially increases LOS and cost.
• Urinary Tract Infection: MRSA UTIs, while less common than gram-negative UTIs, carry significant treatment challenges due to limited oral antibiotic options.
• Osteomyelitis/Septic Arthritis: MRSA is the most common causative agent in hematogenous osteomyelitis, particularly in adults; it often requires prolonged IV vancomycin or daptomycin therapy.
• Bacteremia: MRSA bacteremia is associated with secondary seeding of heart valves, joints, and bones — CDI opportunity if endocarditis or septic emboli are present but not coded.
• Cellulitis/Abscess: Community-acquired MRSA (CA-MRSA) frequently presents as skin and soft tissue infections, especially abscesses; hospital-acquired MRSA (HA-MRSA) is more often associated with invasive procedures.

Manifestation Coding Reminder

ICD-10 CM B95.62 is not a manifestation code in the traditional ICD-10-CM sense (those are found in italic brackets in the Tabular). Rather, it is an etiology/agent code from the B95-B97 block. It should always follow the condition code (site of infection) in sequencing — never precede it as a principal diagnosis. In inpatient facility coding, sequencing is guided by UHDDS definitions: the principal diagnosis is the condition determined after study to be chiefly responsible for admission, not the organism.

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💰 HCC Risk Adjustment

HCC Model	HCC Category	RAF Weight	Notes
CMS-HCC V28	Not Mapped	N/A	B95.62 is an etiology code; does not independently map to HCC
CMS-HCC V24 (legacy)	Not Mapped	N/A	Same — no standalone RAF capture
CDPS / Medicaid	Not Mapped	N/A	Medicaid risk models do not directly capture organism codes

ICD-10 CM B95.62 carries no direct HCC mapping under any current CMS risk adjustment model because it functions as a supplementary organism-identification code rather than a standalone condition. The clinical and financial weight of MRSA infections is captured through the principal condition code (e.g., wound infection, osteomyelitis, bacteremia) paired with B95.62. In value-based care and ACO contracts, presence of MRSA coding signals high clinical complexity and may trigger case management or care coordination flags even without an HCC weight. Coders should ensure the underlying infection code is captured completely, as that code — not B95.62 — will carry any applicable HCC value. Annual documentation of active MRSA infections (versus resolved or carrier status) is essential for accurate risk profiling.

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🏥 MS-DRG Assignment

ICD-10 CM B95.62 does not independently drive MS-DRG assignment. The DRG is governed by the principal diagnosis. However, B95.62 can contribute as a CC (Complication or Comorbidity) depending on the principal diagnosis, which may shift the DRG tier and increase the relative weight.

Scenario	Principal Dx	B95.62 Role	Likely MDC	Example DRG Range
MRSA wound infection post-op	T81.49XA (infection following a procedure)	Additional code (CC potential)	MDC 18 or surgical MDC	Varies by O.R. procedure
MRSA UTI	N39.0 (UTI, site not specified)	Additional code (CC potential)	MDC 11	DRG 689-691
MRSA osteomyelitis	M86.9 (osteomyelitis, unspecified)	Additional code	MDC 8	DRG 539-541
MRSA bacteremia (non-sepsis)	R78.81 (bacteremia)	Additional code	MDC 18	DRG 867-869

When B95.62 functions as a CC, it can elevate reimbursement by moving the encounter from a “without CC/MCC” DRG to a “with CC” DRG tier. Coders must verify the CC/MCC exclusion list — some principal diagnoses exclude B95.62 from CC consideration. In inpatient facility coding, always confirm whether the underlying infection code already fully captures MRSA (combination code check) before assigning B95.62, as improper dual-coding of a combination scenario is a top OIG audit target. When the documentation supports MRSA as the causative agent of the principal diagnosis but no combination code exists, B95.62 is essential for complete and compliant coding and should not be omitted.

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🔗 Related ICD-10-CM Codes

MRSA Combination Codes (Do NOT use with B95.62):

• A41.02 — Sepsis due to Methicillin resistant Staphylococcus aureus
• J15.212 — Pneumonia due to Methicillin resistant Staphylococcus aureus
• A41.01 — Sepsis due to Methicillin susceptible Staphylococcus aureus (MSSA sepsis — for contrast)
• J15.211 — Pneumonia due to Methicillin susceptible Staphylococcus aureus

Related MRSA / Staph Organism & Status Codes:

• B95.61 — Methicillin susceptible Staphylococcus aureus infection as cause of diseases classified elsewhere (MSSA equivalent)
• B95.8 — Unspecified staphylococcus as cause of diseases classified elsewhere (use only when resistance not documented)
• Z22.322 — Carrier or suspected carrier of MRSA (colonization, no active infection)
• Z22.321 — Carrier or suspected carrier of MSSA
• Z86.14 — Personal history of MRSA infection (resolved, no active colonization documented)

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🛠️ Commonly Associated CPT Codes

• 87641 — Infectious agent detection by nucleic acid (DNA or RNA); Staphylococcus aureus, methicillin resistant, amplified probe technique: This is the molecular (PCR) test used to confirm MRSA from a clinical specimen. It is the most specific and commonly billed lab code for MRSA identification; results from this test provide the documentation foundation for coding B95.62 when the provider links it clinically to the infection.

• 87081 — Culture, presumptive, pathogenic organisms, screening only: Used for MRSA screening cultures (e**.g., nasal swabs on admission**), this CPT is paired with Z22.322 for carrier screening scenarios rather than B95.62. Coders should distinguish screening cultures (Z22.322 / Z13.88) from diagnostic cultures supporting an active infection (B95.62).

• 99232 / 99233 — Subsequent hospital care (moderate/high complexity): Inpatient subsequent care E&M codes are frequently billed alongside MRSA infection management. The complexity contributed by MRSA (resistant organism, complex treatment) supports higher MDM levels; B95.62 in the problem list strengthens medical necessity for high-complexity visits.

• 27447 / 27130 (Joint replacement codes) — with MRSA periprosthetic infection: Revision joint procedures associated with MRSA periprosthetic joint infection (PJI) are an area of intensive audit focus in FY2026 given the new DRGs 403/404 for hip/knee procedures with principal diagnosis of PJI. B95.62 would accompany the PJI code (e.g., T84.51XA) in these cases.

• 20005 / 10060 — Incision and drainage of abscess: When MRSA-caused abscesses are surgically drained, these CPT codes are used. The corresponding diagnosis codes would be the abscess code (e.g., L02.416 for cutaneous abscess of left lower limb) plus B95.62.

NCCI Bundling Considerations

ICD-10 CM B95.62 is a diagnosis code, not a CPT, so NCCI procedure-to-procedure edits do not directly apply to it. However, coders should be aware that MRSA diagnostic lab testing (87641) and culture codes (87081, 87070) may be subject to NCCI bundling when multiple culture/sensitivity tests are billed on the same date. On the facility side, laboratory NCCI edits govern whether a presumptive screening culture (87081) can be billed alongside a definitive MRSA molecular test (87641) — payers often bundle the screen into the confirmatory test when both are performed on the same date.

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🔬 ICD-10-PCS Crosswalk

ICD-10 CM B95.62 is an ICD-10-CM diagnosis code and does not have a direct ICD-10-PCS equivalent. However, the following PCS codes are commonly assigned in encounters where B95.62 is also reported:

• 0W9F3ZZ — Drainage of Abdominal Wall, Percutaneous Approach (no device): Used for drainage of MRSA-infected abdominal wall wounds or abscesses. In inpatient settings, incision and drainage procedures require a PCS code; B95.62 supports the diagnosis in the record.
• 0BJ08ZZ — Inspection of Tracheobronchial Tree, Via Natural or Artificial Opening Endoscopic: May be assigned in MRSA lower respiratory tract infection workups requiring bronchoscopy (in the absence of a definitive MRSA pneumonia combination code scenario).
• 3E04305 — Introduction of Other Therapeutic Substance into Central Vein, Percutaneous (Vancomycin): Represents IV vancomycin administration, the first-line treatment for most MRSA infections. In inpatient PCS coding, substance administration may be captured when it is a significant procedure; presence of B95.62 provides the clinical rationale.

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💊 Coding Scenarios and Examples

Scenario 1 — MRSA Wound Infection Post-Appendectomy

A 58-year-old male was admitted for a surgical site infection 10 days after an open appendectomy. The wound culture grew MRSA, and the physician’s progress note states “surgical site infection due to MRSA.” The patient was treated with IV vancomycin, and the wound was irrigated and repacked.

Correct Coding:

• Principal Dx: T81.49XA — Infection following a procedure, other surgical site, initial encounter
• Additional: B95.62 — Methicillin resistant Staphylococcus aureus infection as cause of diseases classified elsewhere
• Additional: Z87.39 — Personal history of other endocrine, nutritional and metabolic diseases (if applicable)

Sequencing: T81.49XA is principal per UHDDS (the condition chiefly responsible for admission after study); B95.62 is additional to identify the resistant organism.
CDI Note: Confirm the provider has explicitly stated “due to MRSA” — a positive culture result alone is insufficient; the physician must link the culture result to the clinical condition in their documentation.

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Scenario 2 — MRSA Urinary Tract Infection

A 72-year-old woman with a history of recurrent UTIs was admitted with fever, dysuria, and urinalysis positive for bacteria. Urine culture confirmed MRSA. The attending physician documented “UTI due to MRSA” in the discharge summary.

Correct Coding:

• Principal Dx: N39.0 — Urinary tract infection, site not specified
• Additional: B95.62 — Methicillin resistant Staphylococcus aureus infection as cause of diseases classified elsewhere

Sequencing: N39.0 is principal; B95.62 is secondary as the organism identifier. Note that there is no combination code for MRSA UTI in ICD-10-CM, making this the correct two-code approach.
CDI Note: If the documentation specifies the exact UTI site (e.g., cystitis, pyelonephritis), use the more specific UTI code rather than N39.0 — query the provider for anatomical site specificity when possible.

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Scenario 3 — MRSA Bacteremia Without Sepsis

A 65-year-old dialysis patient presented with positive blood cultures for MRSA but without systemic inflammatory response syndrome (SIRS) meeting sepsis criteria per Sepsis-3. The attending documented “MRSA bacteremia, not meeting sepsis criteria, monitoring and treating with vancomycin.”

Correct Coding:

• Principal Dx: R78.81 — Bacteremia
• Additional: B95.62 — Methicillin resistant Staphylococcus aureus infection as cause of diseases classified elsewhere
• Additional: Z99.2 — Dependence on renal dialysis

Sequencing: R78.81 is principal; B95.62 identifies the resistant organism. Do NOT assign A41.02 (MRSA sepsis) because the provider explicitly documented the patient does not meet sepsis criteria — code only to the level of provider documentation.
CDI Note: High-value CDI opportunity here — if monitoring and management escalates during the stay or if secondary seeding (e.g., endocarditis, vertebral osteomyelitis) is subsequently identified, a provider query may be warranted to clarify whether sepsis criteria are met.

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⚠️ Coding Pitfalls and Tips

1. Adding B95.62 with combination codes: The most common and high-risk error is assigning B95.62 alongside A41.02 (MRSA sepsis) or J15.212 (MRSA pneumonia). These combination codes already capture the MRSA etiology — adding B95.62 is duplicative, non-compliant with ICD-10-CM Official Guideline I.C.1.e, and a frequent target of Medicare RAC and OIG audits. Always check for a combination code before assigning B95.62. When a combination code exists and applies, use it exclusively.

2. Coding from lab results alone: Coders cannot assign B95.62 solely because MRSA appears in a microbiology or culture report. The attending, treating physician, or authorized provider must clinically link the MRSA organism to the condition being treated in their documentation (progress note, discharge summary, or H&P). If the culture is positive but no provider documentation connects it to a clinical condition, a CDI query is required.

3. Confusing MRSA carrier status with active infection: Z22.322 (MRSA carrier) and B95.62 (active MRSA infection) are not interchangeable. If the patient is screened on admission and found to be colonized with MRSA (nasal swab positive) but has no active MRSA infection, assign**Z22.322** only. If both colonization and an active MRSA infection are documented, both codes can be assigned — but B95.62 must still follow the infection site code.

4. Using B95.62 as a principal diagnosis: B95.62 is structurally designed as a supplementary code and can never be a principal diagnosis. The ICD-10-CM Tabular note for the B95-B97 block explicitly states these codes are for use as additional codes to identify the infectious agent. Assigning B95.62 as the principal diagnosis will fail claim edits and is non-compliant.

5. Missing the CC/MCC capture opportunity: When B95.62 is correctly assigned alongside a principal infection code, it may qualify as a CC, bumping the encounter to a higher-weighted DRG tier. Omitting B95.62 when it is documented and clinically supported results in lost reimbursement. Facility coders should audit MRSA-positive discharges to ensure the code is captured when appropriate.

6. Not querying for specificity when documentation says “staph infection”: If the documentation simply says “staph infection” or “staphylococcal wound infection” without specifying methicillin resistance, coders should not default to B95.62. The correct code in that scenario would be B95.8 (unspecified staphylococcus). A CDI query for resistance status is appropriate and clinically relevant, especially if culture and sensitivity results in the chart suggest MRSA — the provider must make the clinical linkage explicit.

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📚 Sources

¹ Centers for Disease Control and Prevention (CDC). ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.1.e — MRSA Conditions. U.S. Department of Health and Human Services. 2025.
² AAPC. ICD-10 Code B95.62 — Methicillin resistant Staphylococcus aureus infection as the cause of diseases classified elsewhere. AAPC Code Reference. 2023. https://www.aapc.com/codes/icd-10-codes/B95.62
³ Outsource Strategies International. Coding and Documenting MRSA Conditions. OSI Medical Coding Blog. 2025. https://www.outsourcestrategies.com/blog/coding-methicillin-resistant-staphylococcus-aureus-mrsa-conditions/
⁴ IKS Health. Coding MRSA. Cracking the Code Series. 2025. https://ikshealth.com/insights/cracking-the-code/coding-mrsa/
⁵ National Library of Medicine / NLM VSAC. ICD-10-CM Code B95.62 — Descriptor and Code System Info. NIH VSAC Browse. 2023. https://vsac.nlm.nih.gov/context/cs/codesystem/ICD10CM/version/2023/code/B95.62/info
⁶ FindACode. B95.62 Methicillin resistant Staphylococcus aureus infection causing diseases classified elsewhere. 2025. https://www.findacode.com/icd-10-cm/b95.62-methicillin-resistant-staphylococcus-aureus-infection-icd10cm-code.html
⁷ CMS. FY 2026 IPPS Final Rule Home Page. Centers for Medicare & Medicaid Services. 2025. https://www.cms.gov/medicare/payment/prospective-payment-systems/acute-inpatient-pps/fy-2026-ipps-final-rule-home-page
⁸ MedLearn Publishing. 2026 IPPS Expands MS-DRGs, Updates Quality Programs. 2025. https://medlearn.com/2026-ipps-expands-ms-drgs-updates-quality-programs/