Interstitial Lung Disease Viva

Long Case Viva Defence

Candidate's opening statement (model answer)

"Mr Thompson is a 70-year-old retired electrician who presents with 10 months of progressive exertional dyspnoea and dry cough. He is breathless walking 80 metres on flat ground and has recently noticed his fingers changing shape. [1]

His past history includes hypertension and GERD. He is a former smoker with a 45 pack-year history, having quit 8 years ago. He has no known occupational lung disease exposures and takes no drugs associated with ILD. [1]

On examination he has digital clubbing and bilateral basal fine Velcro-like crackles. He is not cyanosed. His oxygen saturation is 94 percent on room air at rest, desaturating to 87 percent on exertion. There is no evidence of cor pulmonale. [1]

His HRCT shows a definite UIP pattern — basal and subpleural reticulation with honeycombing, traction bronchiectasis, and no features suggesting an alternative diagnosis. His PFTs confirm a restrictive defect with FVC 56 percent predicted, TLC 60 percent predicted, DLCO 34 percent predicted. His autoimmune screen is negative. His echocardiogram shows estimated RVSP 45 mmHg with normal right ventricular function. [1]

His main problems are:

1. Idiopathic pulmonary fibrosis — definite UIP, GAP Stage II, moderate-severe disease
2. Exertional desaturation requiring oxygen assessment
3. Possible mild pulmonary hypertension (RVSP 45 mmHg) — needs monitoring
4. GERD — aspiration micro-injury risk
5. Former heavy smoker — cardiovascular and lung cancer risk
6. Progressive functional decline despite no prior therapy" [1]

Examiner probing questions and model answers

Q1: "How confident are you in the diagnosis of IPF, and would you biopsy?" [1]

"I am confident. A definite UIP pattern on HRCT in a patient with exclusion of known causes of ILD is diagnostic of IPF per the 2018 ATS/ERS/JRS/ALAT diagnostic criteria. The HRCT shows all four features of a definite UIP: basal and subpleural reticulation, honeycombing, traction bronchiectasis, and absence of features suggesting an alternative diagnosis — no ground-glass, no perilymphatic nodules, no consolidation, no upper lobe predominance. His autoimmune screen is negative and he has no CTD symptoms, no drug or occupational cause, and no exposure history. A surgical lung biopsy is not required and would carry unnecessary risk given his physiological impairment. The MDT should review and confirm." [1]

Q2: "What is your first pharmacological priority?" [1]

"Initiating antifibrotic therapy. I would offer either nintedanib 150 mg twice daily or pirfenidone titrated to 801 mg three times daily. Both reduce the rate of FVC decline by approximately 50 percent. The INPULSIS trials demonstrated that nintedanib reduced the annual rate of FVC decline from approximately 239 mL/year to 114 mL/year. The ASCEND trial showed pirfenidone reduced the proportion of patients with a 10 percent or greater FVC decline by nearly half, with a pooled mortality benefit. The choice depends on tolerability and patient preference — there is no head-to-head superiority trial. I would counsel him on the expected adverse effects: diarrhoea for nintedanib (manage with loperamide, taking with food, and dose reduction to 100 mg BID if needed), and photosensitivity and nausea for pirfenidone (sunscreen, food, antiemetics). I would monitor LFTs at baseline, then monthly for 3 months, then quarterly." [1]

Q3: "Would you use corticosteroids?" [1]

"No. Corticosteroids are contraindicated in IPF. The PANTHER-IPF trial evaluated triple therapy with prednisone, azathioprine, and N-acetylcysteine and was stopped early by the Data Safety Monitoring Board for harm — the triple therapy arm had significantly increased mortality, more hospitalisations, and more serious adverse events compared to placebo. Corticosteroid monotherapy is equally inappropriate — there is no evidence of benefit and it increases infection risk in a vulnerable population. The only drug therapy for IPF is antifibrotics." [1]

Q4: "His FVC declines by 12 percent over the next 6 months despite nintedanib. What do you do?" [1]

"This confirms progressive disease despite antifibrotic therapy. My first step is to exclude causes of accelerated decline — I would perform repeat HRCT to look for new ground-glass or consolidation suggesting an acute exacerbation, superimposed infection, or malignancy. I would check a bronchoalveolar lavage or sputum culture to exclude infection. If the decline represents disease progression without a reversible cause, I would: (1) ensure he is on the maximum tolerated dose of nintedanib, or consider switching to pirfenidone if tolerability is limiting; (2) urgently escalate lung transplant referral and assessment, as his window may be closing; (3) initiate or reinforce oxygen therapy if he is hypoxaemic; (4) begin advance care planning conversations. Progressive disease despite antifibrotics portends a poor prognosis." [1]

Q5: "He presents acutely with worsening dyspnoea over 5 days, fever, and new bilateral ground-glass on HRCT. What is this and how do you manage it?" [1]

"This is an acute exacerbation of IPF, provided the Collard 2016 criteria are met: previous or concurrent diagnosis of IPF, acute worsening of dyspnoea of less than 1 month, new bilateral ground-glass opacity and/or consolidation on CT superimposed on the background UIP pattern, and deterioration not fully explained by cardiac failure or fluid overload. I would first perform echocardiography and assess volume status to exclude pulmonary oedema, and take cultures to exclude infection. [1]

Management is supportive and empirical, as no RCT has established a standard of care. I would give broad-spectrum antibiotics to cover infection (the most common mimic and trigger), high-dose corticosteroids (IV methylprednisolone 0.5-1 g daily for 3 days then tapering oral prednisolone — evidence is weak but many experts use it given the lack of alternatives), supplemental oxygen to maintain SpO2 at least 88 percent, and consider NIV for moderate respiratory failure as a palliative or bridging measure. Mechanical ventilation is generally not recommended — hospital mortality exceeds 50 percent and approaches 90 percent in severe cases. I would discuss goals of care with the patient and family. I would continue his nintedanib unless drug toxicity is suspected." [1]

Q6: "When would you refer him for lung transplantation?" [1]

"Now. The 2022 ATS/ERS/JRS/ALAT guidelines recommend early referral for lung transplant assessment when FVC is less than 80 percent predicted or DLCO is less than 40 percent predicted — both criteria are met. The workup takes months, and transplant is the only therapy proven to improve survival in progressive IPF. Bilateral sequential lung transplant is the preferred procedure. Major contraindications would include recent malignancy, severe cardiac or hepatic dysfunction, significant obesity (BMI over 35), or poor functional status. At 70 years of age he is at the upper limit, but carefully selected patients up to 70 may be considered at many centres. I would refer him now and let the transplant team determine candidacy." [1]

Short Case Discussion

Scenario: "Examine this patient's respiratory system"

Candidate presentation (model): [1]

"I examined Mrs Chen's respiratory system. She is comfortable at rest at 45 degrees. She is not cyanosed or in respiratory distress. She has digital clubbing bilaterally — Grade 2 by Myers and Farquharson. [1]

The trachea is central. Chest expansion is reduced bilaterally, more so at the bases. On percussion, the chest is resonant throughout. On auscultation, there are fine, bilateral basal end-inspiratory crackles with a Velcro-like quality that do not clear with coughing. There are no wheezes. Vocal resonance is normal. [1]

Examination of the hands reveals no sclerodactyly, no Raynaud-type changes, no Gottron papules, and no rheumatoid nodules. The nailfold capillaries appear normal on inspection. There is no peripheral oedema. The JVP is not elevated. Heart sounds are normal with no loud pulmonary component to the second heart sound. There is no right ventricular heave. [1]

In summary, the findings are consistent with an interstitial lung disease, specifically idiopathic pulmonary fibrosis given the combination of digital clubbing and bilateral basal Velcro-like crackles. The absence of extrapulmonary features argues against a connective tissue disease-associated ILD." [1]

Examiner: "What is the significance of the Velcro-like crackles?" [1]

"Velcro-like crackles are the characteristic auscultatory finding of pulmonary fibrosis. They are caused by the sudden opening of collapsed distal airways and alveoli that have been stiffened and distorted by fibrosis. Unlike the crackles of pulmonary oedema, which are caused by fluid in the airways and shift with position, or the coarse crackles of bronchiectasis, which may clear with coughing, the crackles of fibrosis are fine, dry, end-inspiratory, basal, and persistent. The term Velcro-like comes from their resemblance to the sound of opening a Velcro fastener. Their presence bilaterally at the bases is highly suggestive of a fibrosing ILD, and in the right clinical context — an older patient with progressive dyspnoea — it points toward IPF." [1]

Examiner: "Why did you look at the nailfold capillaries?" [1]

"I examined the nailfold capillaries and the hands to screen for connective tissue disease-associated ILD. In systemic sclerosis, nailfold capillaroscopy shows dilated and distorted capillary loops, avascular areas, and late-stage dropout — these changes can precede clinically apparent skin disease. The presence of sclerodactyly, digital pitting scars, or telangiectasia would suggest systemic sclerosis. Gottron papules or mechanic's hands would suggest dermatomyositis or anti-synthetase syndrome. Rheumatoid nodules or active synovitis would suggest rheumatoid arthritis-associated ILD. Identifying a CTD changes management from antifibrotic-only to immunosuppression plus antifibrotic — it is the single most important aetiological distinction in ILD assessment. The nailfold examination is quick, non-invasive, and high-yield." [1]

Examiner: "How would you confirm your diagnosis?" [1]

"I would order a high-resolution CT scan of the chest, which is the single most important diagnostic test. I would be looking for a UIP pattern — basal and subpleural reticulation with honeycombing and traction bronchiectasis, with absence of features suggesting an alternative diagnosis. If the HRCT shows a definite UIP pattern, and if a thorough history and autoimmune screen exclude known causes, the diagnosis of IPF is made without biopsy. I would also arrange pulmonary function tests to confirm a restrictive pattern with reduced DLCO, an autoimmune panel, and a 6-minute walk test to assess for exertional desaturation. The case would be discussed at the multidisciplinary team meeting for diagnostic confirmation." [1]