J84.113

Billable

Idiopathic non-specific interstitial pneumonitis

HCC Category Mapping

V28HCC 280 — Chronic Obstructive Pulmonary Disease

0.334

V24HCC 112 — Fibrosis of Lung and Other Chronic Lung Disorders

0.268

ESRDHCC 112 — Fibrosis of Lung and Other Chronic Lung Disorders

0.000

RxHCCHCC 227 — Sarcoidosis, Pulmonary Alveolar Disorders

0.000

What This Code Means

A type of lung inflammation with unknown cause that shows a non-specific pattern of scarring and damage on imaging.

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

Excludes 1 — Do NOT code together

non-specific interstitial pneumonia NOS, or due to known underlying cause (J84.89)

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

Code Hierarchy

└J84Other interstitial pulmonary diseases └J84.1Other interstitial pulmonary diseases with fibrosis └J84.11Idiopathic interstitial pneumonia └J84.113Idiopathic non-specific interstitial pneumonitis

└J84.113Idiopathic non-specific interstitial pneumonitis