J84.113 ICD-10-CM Code: Idiopathic non-specific interstitial pneumonitis

Code

J84.113

Description

Idiopathic non-specific interstitial pneumonitis

HCC (V28)

HCC 280 — Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders

RAF reference coefficient

0.319

Billable

Yes

Payment year

2026

HCC Category Mapping

These are source-labeled model coefficients, not member totals. A category may still be removed by hierarchy or model cleanup rules. Weights are not directly comparable across models: CMS-HCC V28 and V24 use Community, Non-Dual, Aged; ESRD uses the dialysis continuing-enrollee model; RxHCC is the Part D continuing-enrollee, non-low-income, aged weight (a larger scale than CMS-HCC). ACA/HHS has no single weight — it varies by metal level. Actual per-patient RAF contribution depends on member context, hierarchy and cleanup rules, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains available for historical review.

Work J84.113 in the Code Book — tabular path, V28 RAF reference, and MEAT checklist →

MEAT review for J84.113

What This Code Means

HCC Buddy maintains structured V28 and V24 mapping, source-labeled coefficient references, and MEAT documentation criteria for J84.113 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

• •Distinguish from idiopathic pulmonary fibrosis (J84.112) which has a more specific pattern
• •Document the clinical presentation and imaging findings that support this diagnosis

Clinical Significance

Idiopathic non-specific interstitial pneumonitis represents a distinct subtype of interstitial lung disease with a generally better prognosis than idiopathic pulmonary fibrosis. This condition requires ongoing immunosuppressive therapy, pulmonary function monitoring, and specialist follow-up. Accurate coding distinguishes it from IPF and ensures appropriate risk-adjusted reimbursement for the chronic management these patients need.

Documentation Requirements

• ✓High-resolution computed tomography showing NSIP pattern (ground-glass opacities with or without reticulation, subpleural sparing)
• ✓Lung biopsy results if performed, confirming NSIP pattern rather than UIP
• ✓Documentation excluding secondary causes such as connective tissue disease, drug toxicity, or hypersensitivity pneumonitis
• ✓Pulmonary function test results documenting severity
• ✓Treatment plan including immunosuppressive agents if applicable

Commonly Confused Codes

• •J84.112: Idiopathic pulmonary fibrosis has a UIP pattern on imaging/biopsy and carries a much worse prognosis and higher HCC weight
• •J84.111: Idiopathic interstitial pneumonia NOS should only be used when the specific subtype cannot be determined
• •M35.02: Sicca syndrome with lung involvement may cause NSIP pattern but is coded differently as secondary NSIP
• •J84.89: Other specified interstitial pulmonary diseases is a catch-all that should not be used when NSIP is documented

Child Codes