Interstitial Lung Disease — Clinical Case

DCE Long Case

Patient brief (provided to trainee)

Patient: Mrs Margaret Davies, 52 years old. [1]

Presenting complaint: Progressive exertional dyspnoea over 18 months, now breathless walking 50 metres on flat ground. Dry cough. Episodes of palpitations. Increasing fatigue. She has noticed her fingers becoming stiff and tight with colour changes on cold exposure. [1]

Past history:

• Raynaud phenomenon diagnosed 4 years ago
• Hypertension
• GERD with dysphagia to solids
• No significant smoking history (never-smoker) [1]

Current medications:

• Amlodipine 10 mg OD (for Raynaud and hypertension)
• Omeprazole 20 mg OD (for GERD)
• Frusemide 20 mg OD (recently started for ankle swelling) [1]

Examination findings (trainee elicits):

• Alert, comfortable at rest at 45 degrees, mild cachexia
• SpO2 93 percent on room air at rest, desaturating to 85 percent on walking to the toilet
• Bilateral basal fine Velcro-like crackles
• Digital pitting scars on the fingertips, sclerodactyly, perioral radial furrowing (rhagades), telangiectasia on palms
• Nailfold capillaroscopy: dilated and tortuous capillary loops with dropout areas
• Loud P2, RV heave present, JVP elevated 4 cm
• Bilateral pitting ankle oedema to mid-shin
• Blood pressure 125/80 [1]

Investigations:

• PFTs: FVC 62 percent predicted, FEV1/FVC 0.88, TLC 60 percent predicted, DLCO 40 percent predicted (disproportionately reduced)
• HRCT: bilateral symmetric basal ground-glass opacity and fine reticulation with traction bronchiectasis (NSIP pattern), no honeycombing
• ANA positive 1:1280 (nucleolar pattern), anti-Scl-70 positive
• RF negative, anti-Jo-1 negative, CK normal
• Echocardiography: estimated RVSP 52 mmHg, mildly dilated right ventricle with preserved systolic function, normal LV
• Right heart catheterisation (pending): to characterise pulmonary haemodynamics
• 6-minute walk test: 210 metres, SpO2 from 93 percent to 84 percent [1]

Candidate's structured presentation (model)

Opening statement: [1]

"Mrs Davies is a 52-year-old woman who presents with 18 months of progressive exertional dyspnoea and dry cough. She has a 4-year history of Raynaud phenomenon and has recently developed skin thickening of her fingers (sclerodactyly). [1]

Her examination reveals bilateral basal Velcro-like crackles consistent with an interstitial lung disease, along with extrapulmonary features of systemic sclerosis — digital pitting scars, sclerodactyly, perioral radial furrowing, palmar telangiectasia, and abnormal nailfold capillaries. She also has signs of pulmonary hypertension with a loud P2, right ventricular heave, elevated JVP, and peripheral oedema. [1]

Her HRCT shows an NSIP pattern — bilateral symmetric basal ground-glass and reticulation, which is the characteristic ILD pattern in systemic sclerosis. Her PFTs confirm restriction with a disproportionately reduced DLCO, suggesting overlapping pulmonary hypertension. Her autoantibodies confirm diffuse systemic sclerosis (ANA nucleolar pattern, anti-Scl-70 positive). Her echo estimates RVSP of 52 mmHg with a mildly dilated right ventricle. [1]

Her main problems are:

1. Systemic sclerosis-associated interstitial lung disease (SSc-ILD) — NSIP pattern, FVC 62 percent, progressive
2. Pulmonary hypertension — likely WHO Group 1 (PAH associated with SSc) overlapping with Group 3 (PH due to ILD), needs right heart catheterisation
3. Raynaud phenomenon and digital vascular disease
4. GERD with oesophageal dysmotility — aspiration risk
5. Right heart failure — peripheral oedema, elevated JVP
6. Deconditioning and cachexia" [1]

Management plan: [1]

1. SSc-ILD treatment — dual therapy:

   • Mycophenolate mofetil 1-1.5 g BID — first-line immunosuppressant for SSc-ILD. The Scleroderma Lung Study II showed equivalence to cyclophosphamide with better tolerability and sustained benefit. Monitor FBC, LFTs monthly.
   • Nintedanib 150 mg BID — the INBUILD trial (PMID 31566307) demonstrated that nintedanib reduces FVC decline in progressive fibrosing ILDs including SSc-ILD. Start now given her progressive course. [1]

2. Pulmonary hypertension management:

   • Complete right heart catheterisation to differentiate PAH (Group 1) from PH due to ILD (Group 3)
   • If PAH confirmed, initiate pulmonary vasodilator therapy under PH specialist — ambrisentan, sildenafil, or riociguat as first-line, with combination therapy for inadequate response
   • Optimise right heart failure: cautious diuretic therapy (frusemide), avoid excessive diuresis that could precipitate scleroderma renal crisis [1]

3. Oxygen therapy:

   • Prescribe long-term supplemental oxygen — she meets criteria with exertional desaturation to 85 percent and likely meets resting PaO2 criteria (confirm with ABG) [1]

4. Gastrointestinal management:

   • Continue PPI; add a prokinetic (domperidone) for oesophageal dysmotility
   • Consider dietary modification for dysphagia [1]

5. Raynaud and digital vascular disease:

   • Continue calcium channel blocker (amlodipine)
   • Add a phosphodiesterase inhibitor (sildenafil) if digital ulcers develop
   • Bosentan for prevention of recurrent digital ulcers [1]

6. Renal surveillance:

   • Monitor blood pressure twice weekly — any rise in creatinine or new hypertension mandates immediate ACE inhibitor initiation for scleroderma renal crisis
   • Avoid high-dose corticosteroids (greater than 15 mg/day prednisolone equivalent) — increases scleroderma renal crisis risk [1]

7. General measures:

   • Pulmonary rehabilitation
   • Vaccinations (influenza, pneumococcal, COVID-19)
   • Nutritional support for cachexia
   • Early advance care planning [1]

Examiner discussion questions

Q: "Why does she have a disproportionately reduced DLCO?" [1]

"The DLCO of 40 percent is disproportionately reduced relative to the FVC of 62 percent. In isolated ILD, the DLCO reduction typically parallels the volume loss. When the DLCO is disproportionately low, it suggests an additional process impairing gas exchange — most commonly pulmonary hypertension. In systemic sclerosis, this pattern is particularly important because SSc is associated with both ILD (Group 3 PH) and pulmonary arterial hypertension (Group 1). The echo estimate of 52 mmHg supports this. A right heart catheterisation is essential to characterise the pulmonary haemodynamics, determine the precise PH classification, and guide vasodilator therapy." [1]

Q: "How does her scleroderma renal crisis risk influence your drug choices?" [1]

"Scleroderma renal crisis is a life-threatening complication of diffuse systemic sclerosis characterised by malignant hypertension, acute kidney injury, and microangiopathic haemolytic anaemia. Corticosteroids at doses above 15 mg/day prednisolone equivalent are a major risk factor. For this reason, I would avoid high-dose corticosteroids entirely in this patient. My immunosuppression strategy uses mycophenolate mofetil and nintedanib, neither of which carries renal crisis risk. I would also educate her to monitor her blood pressure twice weekly and to present immediately if her blood pressure rises — captopril is the ACE inhibitor of choice for scleroderma renal crisis due to its rapid onset." [1]

Q: "What is the prognosis?" [1]

"The prognosis of SSc-ILD is better than that of IPF — NSIP is generally more treatment-responsive than UIP, and immunosuppression can stabilise or improve the inflammatory component. However, her prognosis is significantly worsened by the presence of pulmonary hypertension. Untreated PAH associated with systemic sclerosis carries a 3-year survival of approximately 40-50 percent. With modern PAH therapy (endothelin receptor antagonists, phosphodiesterase-5 inhibitors, riociguat, and potentially parenteral prostacyclins), survival has improved substantially. Her ILD also requires antifibrotic therapy (nintedanib) for the progressive fibrotic component. The integrated care of a patient with SSc-ILD and PAH requires close collaboration between respiratory medicine, rheumatology, cardiology, and the ILD/PH nursing team." [1]

DCE Short Case — Respiratory Examination

Instruction

"Examine this patient's respiratory system. You have 7 minutes for examination and 8 minutes for discussion." [1]

Key signs the patient demonstrates

• Digital clubbing (Grade 2) — present in approximately 50 percent of IPF patients
• Bilateral basal fine Velcro-like crackles — do not clear with coughing
• Reduced chest expansion bilaterally
• Tachypnoea at rest
• Exertional desaturation (if measured during examination)
• Signs of pulmonary hypertension (in advanced disease): loud P2, RV heave, raised JVP, peripheral oedema
• Extrapulmonary signs (if CTD-ILD): sclerodactyly, digital pitting scars, telangiectasia, Gottron papules, mechanic's hands, Raynaud-type changes [1]

Presentation template

"I examined this patient's respiratory system. At 45 degrees, he is comfortable at rest. There is digital clubbing, Grade 2. There is no central or peripheral cyanosis. [1]

The hands reveal no sclerodactyly, no digital pitting scars, no Gottron papules, and no evidence of active arthritis. Nailfold capillaries appear normal on inspection. [1]

The trachea is central. Chest expansion is symmetrically reduced, approximately 3 cm. Percussion note is resonant throughout. On auscultation, there are fine bilateral basal end-inspiratory crackles with a Velcro-like quality that do not clear on coughing. There are no wheezes. Vocal resonance is preserved. [1]

Examination of the cardiovascular system reveals a normal JVP, normal heart sounds with no accentuation of the pulmonary component, and no peripheral oedema. [1]

In summary, the findings of digital clubbing and bilateral basal Velcro-like crackles, in the absence of extrapulmonary features, are consistent with idiopathic pulmonary fibrosis. I would confirm this with an HRCT of the chest and pulmonary function tests." [1]

Discussion template

1. Summarise findings → "Digital clubbing with bilateral basal Velcro-like crackles — the cardinal signs of a fibrosing interstitial lung disease." [1]

2. Differential diagnosis from signs → "The most likely diagnosis is idiopathic pulmonary fibrosis given the combination of clubbing and bilateral basal crackles. Other causes of bilateral basal crackles to consider are pulmonary oedema (but the crackles are positional and there would be cardiovascular signs), bronchiectasis (coarse, mid-inspiratory, may clear with coughing), and atypical infection. The absence of extrapulmonary features of connective tissue disease makes CTD-ILD less likely but does not exclude it — occult CTD-ILD is common and every ILD patient requires a full autoimmune panel." [1]

3. Investigation plan → "HRCT is the single most important test. I would look for a definite UIP pattern — basal and subpleural reticulation, honeycombing, traction bronchiectasis, with absence of features suggesting an alternative diagnosis. PFTs would confirm restriction with reduced DLCO. A full autoimmune panel, 6-minute walk test, and echocardiography complete the initial assessment. The diagnosis should be confirmed at a multidisciplinary team meeting." [1]

4. Management principles → "If IPF is confirmed: antifibrotic therapy (nintedanib or pirfenidone), oxygen for hypoxaemia, pulmonary rehabilitation, vaccination, early transplant referral, and advance care planning. Corticosteroids are contraindicated — the PANTHER-IPF trial demonstrated harm with triple immunosuppressive therapy." [1]