OVERVIEW

  • Even after extensive clinical, radiologic, and/or pathologic examination physicians may still be unable to classify a patient's idiopathic interstitial pneumonia (IIP)1
  • In these cases, the pulmonologist should determine the best course of treatment based on the most probable diagnosis after a detailed discussion with the pathologist and radiologist1

This category designation should not be used for cases in which the distinction between the usual interstitial pneumonia (UIP) and fibrosing nonspecific interstitial pneumonia (NSIP) patterns is difficult.1

Most common reasons for an unclassifiable diagnosis are conflicting data or lack thereof.2

  • 10% of all ILDs are considered unclassifiable2

FIVE MAIN REASONS FOR AN “UNCLASSIFIABLE” DIAGNOSIS2

  1. Conflicting clinical/radiologic/histopathologic data
  2. No biopsy: high surgical risk
  3. No biopsy: mild/stable disease 
  4. No biopsy: unwillingness of patient
  5. Insufficient tissue on biopsy

EPIDEMIOLOGY

SURVIVAL AND MORTALITY2

Survival

  • >50% 5-year survival rate
  • 20% better survival than patients with IPF 

Predictors of Mortality

  • DLCO <35%
  • High fibrosis score on HRCT
  • Former smoker

See also

Patient Case Study 1

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Bridging Educational Gaps in ILD

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Interstitial lung disease in systemic sclerosis with a focus on chest CT

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