The ICD-10 code for leukocytosis is typically D72.829 (Elevated white blood cell count, unspecified) when the provider documents leukocytosis/elevated WBC without specifying the cell type or cause. If documentation identifies a specific elevated WBC subtype (e.g., lymphocytosis), code that instead. Always verify in the ICD-10-CM tabular list and guidelines.
What is leukocytosis?
Leukocytosis means an elevated white blood cell (WBC) count. It’s a lab finding or diagnosis statement that can occur in many clinical contexts (for example, infection, inflammation, stress response, medication effects, or hematologic disorders).
Coding note: Leukocytosis is not the same as a definitive underlying diagnosis—code based on what the provider documents as the condition being evaluated/treated, supported by the record (no patient-specific medical advice).
Correct ICD-10-CM code(s) for leukocytosis and when to use
In ICD-10-CM, leukocytosis is generally coded within the D72.82- family (Elevated white blood cell count). The right code depends on the provider’s documented specificity and whether the elevated WBC is further characterized.
Primary code most commonly used
- D72.829 — Elevated white blood cell count, unspecified
- Use when the provider documents “leukocytosis” or “elevated WBC” and does not specify the type of elevated leukocytes (e.g., lymphocytosis, monocytosis) or a more specific elevated WBC condition.
This is why you’ll often see “D72.829 leukocytosis” mentioned: it’s a common “unspecified” code for leukocytosis when documentation doesn’t support a more specific selection.
When NOT to default to D72.829
Don’t “guess” D72.829 if documentation supports something more specific or a different diagnosis. ICD-10-CM rules require you to locate the term in the Index and verify the final code in the Tabular List, reporting the highest specificity documented.
Related codes you may see (choose only if documented and verified)
If the provider documents a specific elevated WBC subtype, code that specific condition instead of unspecified leukocytosis when appropriate. Examples within the elevated WBC category include:
- D72.820 — Lymphocytosis (symptomatic)
- D72.821 — Monocytosis (symptomatic)
- Other elevated WBC codes also exist in the D72.82- range (e.g., “other elevated white blood cell count”), and should be selected only when documentation supports and you verify in tabular + notes.
Core rule: code based on provider documentation
Your “leukocytosis diagnosis code” should match the provider’s assessment and the encounter purpose (what’s being evaluated/managed), not just a standalone lab value copied forward. Use the Index → Tabular → notes/guidelines workflow every time.
Leukocytosis vs leukopenia (avoid confusion)
The ICD-10-CM categories are different, and mixing them up is a common claim error.
- Leukocytosis / elevated WBC: typically D72.82- family (e.g., D72.829 when unspecified).
- Leukopenia / decreased WBC: typically D72.81- family (e.g., D72.819 — Decreased white blood cell count, unspecified).
Practical tip: If your problem list says “leukocytosis” but the lab trend is low WBC, pause and reconcile—coding should follow the provider’s final documented diagnosis for that encounter.
Documentation tips for clean coding
Clean leukocytosis coding starts with clear provider documentation about what the elevated WBC means in this visit. Coders can’t infer cause, acuity, or significance from labs alone.
What providers should document (when clinically applicable):
- Diagnosis statement: “leukocytosis” (or “elevated WBC”) in the Assessment, not only in labs
- Clinical context/cause (if known): suspected or confirmed driver (e.g., infection/inflammation, medication effect, post-procedure status, hematologic condition)—don’t over-specify if not established
- Linked symptoms/conditions being addressed: what is being evaluated/treated today that relates to leukocytosis (supports medical necessity)
- Lab data summary: relevant WBC value and trend (e.g., improving/worsening), especially if it affects management
- Acuity/timing: acute vs chronic/persistent (if documented)
- Associated conditions: when assessed and relevant (e.g., fever, diagnosed infection, steroid use)—documented linkage helps coding and denials
- Plan: what was done (repeat CBC, cultures, imaging, consult, treatment changes)
Why this matters: ICD-10-CM guidelines emphasize using documentation to assign the most specific code and validating in the Tabular List, not selecting codes based only on shorthand terms.
Common claim/denial pitfalls + how to avoid
Most leukocytosis denials aren’t because D72.829 is “wrong”—they’re because documentation and claim context don’t support why it’s reported. Here are common issues and fixes:
- Pitfall: Coding from labs only (no provider diagnosis)
- Avoid: Ensure leukocytosis is documented as an assessed condition (or that the claim reflects the confirmed condition being treated instead).
- Pitfall: Using unspecified (D72.829) when documentation supports a specific subtype
- Avoid: If the provider clearly documents a specific elevated WBC subtype, validate and code it (don’t default to unspecified).
- Pitfall: Reporting leukocytosis when the underlying confirmed diagnosis explains the finding
- Avoid: If the encounter is for a confirmed condition (e.g., a documented infection) and leukocytosis is simply a lab manifestation, confirm whether leukocytosis is separately assessed/managed. When in doubt, verify in the ICD-10-CM tabular + guidelines and follow coding conventions.
- Pitfall: Leukocytosis vs leukopenia mix-up
- Avoid: Train teams to cross-check the term and lab direction; use the correct family (D72.82- vs D72.81-).
- Pitfall: Medical necessity edits for diagnostic testing
- Avoid: Ensure the claim diagnosis set reflects the reason for the test (symptoms/conditions evaluated and documented), not a vague standalone lab term, and keep payer policy awareness in your workflow.
FAQs
What is the ICD-10 code for leukocytosis?
Most commonly, leukocytosis is coded as D72.829 (Elevated white blood cell count, unspecified) when the provider documents leukocytosis/elevated WBC without more detail.
Is D72.829 the same as leukocytosis?
Often, yes—D72.829 is commonly used as the leukocytosis diagnosis code when the elevated WBC is unspecified. Always verify in the ICD-10-CM tabular list and notes.
When should I use D72.829 vs a more specific code?
Use D72.829 only when documentation doesn’t specify the elevated cell type or a more specific elevated WBC condition. If a subtype like lymphocytosis is documented, code that instead (after tabular verification).
What’s the difference between leukocytosis and leukopenia in ICD-10?
Leukocytosis is high WBC (typically D72.82-), while leukopenia is low WBC (e.g., D72.819 when unspecified).
Can I code leukocytosis from an abnormal lab value alone?
Coding should be based on the provider’s documented diagnosis/assessment and verified in ICD-10-CM (Index and Tabular List). Labs can support the diagnosis but don’t replace documentation.
Where is leukocytosis found in ICD-10-CM?
Leukocytosis-related codes are generally under D72 (Other disorders of white blood cells), including the D72.82- elevated WBC category.
Does leukocytosis affect medical necessity?
It can. Payers may apply claim edits based on diagnosis coding and the services billed, so documentation should clearly support the reason for tests/treatment associated with leukocytosis. (Always check payer policy requirements.)
What should providers document to support leukocytosis coding?
Document the diagnosis in the Assessment, the clinical context (if known), relevant lab trend, and how it influenced evaluation/management. This supports accurate ICD-10-CM diagnosis coding and cleaner claims.
Conclusion
The ICD-10 code for leukocytosis is most often D72.829 when the elevated WBC is documented but unspecified. For best results, follow the Index → Tabular verification workflow, code to the highest specificity supported, and ensure provider documentation explains the clinical context—not just the lab value.
If your team is seeing denials or inconsistent use of D72.829, run a quick audit of recent claims and align providers on a simple documentation template for abnormal CBC findings.
