Clinician reference tool — not medical advice. This is a clinical decision-aid intended for healthcare professionals: it gives deterministic suggestions to think with, not a diagnosis or a prescription. If you’re a patient, you’re welcome to look around — but please review anything here with your own doctor; it isn’t a substitute for personalized medical care.
Clinician reference tool — not a prescriber, not a diagnosis, not medical advice. For PRIMARY CARE: primary care's job in ILD is EARLY RECOGNITION and REFERRAL — "we need your ears and the story." The treatment decision-tree is included so a competent generalist can hold the big picture with the humility to check with the expert; every treatment node is specialist-initiated. Runs entirely in your browser — no data is collected.

Evidence: King TE Jr, Bradford WZ, Castro-Bernardini S 2092 · sources last checked 2026-07-30

Interstitial lung disease — recognise, work up, refer

A primary-care reference for the ILD story: recognition and urgency, a differential-pattern lens from the exposures and imaging, the pre-referral workup, and — keyed to the (suspected) pattern — the treatment decision-tree the specialist will walk, so you can hold the big picture and refer well.

Guideline lens

Recognition & referralconcern: low

Recognition mode: ILD is a story you hear before you see. Feature the three pearls, then use the differential and pre-referral workup — and refer to respirology.

1 · The story is the test

ILD is exertional dyspnea + a DRY cough + a drop in what the patient can do. It is insidious and easily misattributed to age, deconditioning, asthma or COPD. Primary care's job is to hear it and refer — 'we need your ears and the story.'

2 · Never ignore Velcro crackles

Fine bibasilar 'Velcro' crackles that persist after deep breaths (atelectatic crackles clear) must not be ignored. At minimum order a CXR PA + lateral '?ILD'. If it is abnormal → CT chest + respirology. If it is normal but the crackles persist → still get a CT chest.

3 · Order a PFT

COPD is a spirometric diagnosis; chronic bronchitis is a clinical one; a RESTRICTIVE pattern points to ILD — and COPD and ILD can coexist. When the picture doesn't fit, order a PFT (spirometry + lung volumes + DLCO).

The story

Symptoms

Exposure & risk factors

Imaging on hand

Age band

Working pattern (optional pivot)— pick only if you already have a working diagnosis; otherwise the differential infers it

Signs on exam

These drive the recognition/urgency read. Acute worsening + hypoxemia fires the ILD-flare gate.

2

Differential-pattern lens

Likely-progressive (IPF / PF-ILD) vs likely-stable (post-infectious / healed injury). IPF is a diagnosis of exclusion.

Add exposures, imaging findings or an age band to rank the likely patterns.

3

Pre-referral workup

  • Imaging pathway

    CXR PA + lateral '?ILD' → CT chest '?ILD'. Writing '?ILD' on the CT requisition auto-protocolizes a non-contrast HRCT. Don't delay the respirology referral to wait for imaging.

  • Pulmonary function tests (PFT)

    Spirometry + lung volumes + DLCO. ILD is typically RESTRICTIVE with a reduced DLCO. Remember COPD and ILD can coexist — order the PFT when the picture doesn't fit.

  • Exertional SpO₂

    Measure oxygen saturation AFTER walking, not just at rest — exertional desaturation appears before resting hypoxemia.

  • Gather prior imaging for comparison

    Old CXRs/CTs are gold. A scar unchanged over years = far better prognosis (a healed process, not progressive fibrosis). Progression over time changes the whole approach.

  • Screen for occult connective-tissue disease

    Baseline autoimmune serology (ANA, RF, anti-CCP, ENA, CK, inflammatory markers, ACE) — occult CTD can present first as ILD. If any is positive or CTD is suspected, expand to the full CTD-ILD panel and antibody table.

4

Treatment decision-tree

Undifferentiated — needs workupinferred from the differential
Specialist-initiated — confirm the pattern with respirology ± rheumatology. Antifibrotics / immunosuppression are specialist-started; the generalist holds the big picture, the expert confirms and initiates. Mindless handoff is not enough.

Not enough to favour a pattern yet — complete the pre-referral workup and refer. The cross-cutting supportive care below applies to every ILD.

Cross-cutting supportive care — applies to every pattern (7)

Supplemental oxygen

supportive care

Supportiveevidence: Moderate
Evidence strength
Moderate
Disease-modifying
Low
Tolerability / safety
High
  • ▸Supportive care — applies to every ILD pattern regardless of cause.[2]

Specialist framing: Specialist-confirmed: confirm the pattern with respirology. The generalist recognises and refers; the expert confirms and initiates.

For exertional and then resting hypoxemia. Assess with an exertional SpO₂ (walk test), not just a resting reading.

Pulmonary rehabilitation

supportive care

Supportiveevidence: Moderate
Evidence strength
Moderate
Disease-modifying
Moderate
Tolerability / safety
High
  • ▸Supportive care — applies to every ILD pattern regardless of cause.[2]

Specialist framing: Specialist-confirmed: confirm the pattern with respirology. The generalist recognises and refers; the expert confirms and initiates.

Improves exercise capacity, dyspnea and quality of life across fibrotic ILDs.

Vaccination

supportive care

Supportiveevidence: Moderate
Evidence strength
Moderate
Disease-modifying
Low
Tolerability / safety
High
  • ▸Supportive care — applies to every ILD pattern regardless of cause.[3]

Specialist framing: Specialist-confirmed: confirm the pattern with respirology. The generalist recognises and refers; the expert confirms and initiates.

Influenza, pneumococcal and COVID vaccination — a chest infection can precipitate an ILD flare.

Smoking cessation

supportive care

Supportiveevidence: Moderate
Evidence strength
Moderate
Disease-modifying
Moderate
Tolerability / safety
High
  • ▸Supportive care — applies to every ILD pattern regardless of cause.

Specialist framing: Specialist-confirmed: confirm the pattern with respirology. The generalist recognises and refers; the expert confirms and initiates.

COPD and ILD can coexist; smoking cessation matters for every pattern.

Palliative symptom management

supportive care

Supportiveevidence: Moderate
Evidence strength
Moderate
Disease-modifying
Low
Tolerability / safety
High
  • ▸Supportive care — applies to every ILD pattern regardless of cause.[3]

Specialist framing: Specialist-confirmed: confirm the pattern with respirology. The generalist recognises and refers; the expert confirms and initiates.

Cough and refractory dyspnea are major symptom burdens — palliative approaches (including early palliative-care involvement) run alongside disease-directed therapy.

Lung-transplant referral (advanced)

transplant

Supportiveevidence: Moderate
Evidence strength
Moderate
Disease-modifying
High
Tolerability / safety
Moderate
  • ▸Advanced disease — refer EARLY, before the patient is too sick to be a candidate.[2]

Specialist framing: Specialist-initiated: transplant assessment is a transplant-centre decision. Refer EARLY for advanced/progressive fibrosis — do not wait until the patient is too sick to be a candidate.

For advanced progressive fibrosis (especially IPF). Early referral matters — transplant is the only intervention that changes the trajectory of end-stage disease.

Treat comorbidities (GERD, PH, OSA, emphysema)

supportive care

Supportiveevidence: Low
Evidence strength
Moderate
Disease-modifying
Moderate
Tolerability / safety
High
  • ▸Supportive care — applies to every ILD pattern regardless of cause.[2]

Specialist framing: Specialist-confirmed: confirm the pattern with respirology. The generalist recognises and refers; the expert confirms and initiates.

Manage GERD/microaspiration, pulmonary hypertension, OSA and combined emphysema. (The 2022 IPF guideline made conditional recommendations AGAINST routine anti-reflux medication/surgery specifically to slow IPF — treat GERD on its own merits.)

5

Referral & patient message

Refer to respirology. Do NOT delay the referral to complete imaging — refer and work up in parallel.

Send the story

  • ▸Full medication list (flag methotrexate, nitrofurantoin/Macrobid, amiodarone, chemo/immunotherapy).
  • ▸Exposures, hobbies and occupation (birds, mould/water damage, asbestos, silica / engineered-stone cutting, coal, farming).
  • ▸Any connective-tissue-disease history or symptoms (Raynaud, arthritis, rash, dry eyes/mouth, dysphagia).
  • ▸Prior imaging for comparison — stable-over-years vs progressive.
  • ▸Symptom timeline (dyspnea, dry cough, activity change) and exam (Velcro crackles, clubbing, resting/exertional SpO₂).

What to tell the patient

Pitch it honestly, in the middle: don't over-scare (many patterns are stable or treatable, and some scars never progress), but don't underplay it either. Early diagnosis matters — symptoms can precede an IPF diagnosis by around two years, and longer diagnostic delay is independently linked to worse survival, so getting the workup and referral moving is the point.

Safety & guideline notes

  • • Per the CTS position statement on comprehensive management of fibrotic ILD (2018): confirm the diagnosis by multidisciplinary discussion at an ILD centre; offer an antifibrotic (pirfenidone or nintedanib) in IPF; treat the underlying cause in secondary ILD; and wrap every patient in supportive care (oxygen, pulmonary rehab, vaccination, comorbidity management, early transplant referral and palliation).
  • • This tool does not diagnose ILD or choose therapy. Diagnosis rests on HRCT + multidisciplinary discussion at an ILD centre; ALL treatment (antifibrotics, immunosuppression) is specialist-initiated. Primary care's job is early recognition and referral — hold the big picture, confirm with the expert.

Per CTS / Canada — CTS position statement — Comprehensive management of fibrotic ILD (Shapera et al.) (2018).

References

  1. [1]Raghu G, Remy-Jardin M, Myers JL, et al. Diagnosis of Idiopathic Pulmonary Fibrosis. An Official ATS/ERS/JRS/ALAT Clinical Practice Guideline. Am J Respir Crit Care Med 2018;198(5):e44–e68. link
  2. [2]Raghu G, Remy-Jardin M, Richeldi L, et al. Idiopathic Pulmonary Fibrosis (an Update) and Progressive Pulmonary Fibrosis in Adults: An Official ATS/ERS/JRS/ALAT Clinical Practice Guideline. Am J Respir Crit Care Med 2022;205(9):e18–e47. link
  3. [3]Shapera S, Simon J, Singer LG, Fell CD. Comprehensive management of fibrotic interstitial lung diseases: A Canadian Thoracic Society position statement. Can J Respir Crit Care Sleep Med 2018;2(4):234–243. link
  4. [4]Richeldi L, du Bois RM, Raghu G, et al. Efficacy and safety of nintedanib in idiopathic pulmonary fibrosis (INPULSIS). N Engl J Med 2014;370(22):2071–2082. link
  5. [5]King TE Jr, Bradford WZ, Castro-Bernardini S, et al. A phase 3 trial of pirfenidone in patients with idiopathic pulmonary fibrosis (ASCEND). N Engl J Med 2014;370(22):2083–2092. link
  6. [6]Flaherty KR, Wells AU, Cottin V, et al. Nintedanib in progressive fibrosing interstitial lung diseases (INBUILD). N Engl J Med 2019;381(18):1718–1727. link
  7. [7]Distler O, Highland KB, Gahlemann M, et al. Nintedanib for systemic sclerosis–associated interstitial lung disease (SENSCIS). N Engl J Med 2019;380(26):2518–2528. link
  8. [8]Idiopathic Pulmonary Fibrosis Clinical Research Network (Raghu G, Anstrom KJ, King TE Jr, et al.). Prednisone, azathioprine, and N-acetylcysteine for pulmonary fibrosis (PANTHER-IPF). N Engl J Med 2012;366(21):1968–1977. (Triple-therapy arm stopped early for increased death and hospitalization.) link
  9. [9]Jee AS, Adelstein S, Bleasel J, et al. Role of autoantibodies in the diagnosis of connective-tissue disease ILD (CTD-ILD) and interstitial pneumonia with autoimmune features (IPAF). J Clin Med 2017;6(5):51. link
  10. [10]Meyer KC. Diagnosis and management of interstitial lung disease. Transl Respir Med 2014;2:4. link
  11. [11]Lamas DJ, Kawut SM, Bagiella E, et al. Delayed access and survival in idiopathic pulmonary fibrosis: a cohort study. Am J Respir Crit Care Med 2011;184(7):842–847. (Median ~2.2-year delay from dyspnea onset to ILD-centre evaluation; longer delay independently associated with higher mortality.) link
  12. [12]Health Canada — Drug Product Database & product monographs: nintedanib (Ofev — IPF 2015, SSc-ILD 2019, chronic fibrosing ILD with progressive phenotype 2020) and pirfenidone (Esbriet — IPF 2012). link