Interstitial Lung Disease — Clinical Case

DCE Long Case

Patient brief (provided to trainee)

Patient: Mrs Margaret Davies, 52 years old. ^[5]

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. ^[5]

Past history:

• Raynaud phenomenon diagnosed 4 years ago
• Hypertension
• GERD with dysphagia to solids
• No significant smoking history (never-smoker) ^[5]

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) ^[5]

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 ^[5]

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 ^[5]

Candidate's structured presentation (model)

Opening statement: ^[5]

"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). ^[5]

"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. ^[5]

"Her HRCT shows an NSIP pattern — bilateral symmetric basal ground-glass and reticulation, the usual exam pattern in systemic sclerosis (contrast with IPF's UIP). Her PFTs confirm restriction with a disproportionately reduced DLCO, raising overlapping pulmonary hypertension until catheterised. 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. A sourced RVSP cut-off is not in the cited abstracts. ^[5]

"Her main problems are:

1. Systemic sclerosis-associated interstitial lung disease (SSc-ILD) — NSIP pattern, FVC 62 percent, progressive. SENSCIS: ILD is a common manifestation of systemic sclerosis and a leading cause of systemic sclerosis-related death
2. Pulmonary hypertension — Group 1 versus Group 3 until right heart catheterisation; named vasodilators are exam convention, not 2022 ATS questions
3. Raynaud phenomenon and digital vascular disease
4. GERD with oesophageal dysmotility — treat as SSc comorbidity, not as IPF antacid therapy
5. Right heart failure — peripheral oedema, elevated JVP
6. Deconditioning and cachexia" ^[5][1]

Management plan: ^[5][6]

1. SSc-ILD treatment:

   • Mycophenolate mofetil 1500 mg twice daily for 24 months was the SLS II target versus oral cyclophosphamide 2.0 mg/kg per day for 12 months. Primary endpoint negative (p=0.24); both arms improved %FVC (2.19 versus 2.88). Leucopenia 4 versus 30. Prefer mycophenolate for tolerability, not greater 24-month efficacy. Do not write “equivalence trial, therefore first-line by efficacy.” SLS I: oral cyclophosphamide 2 mg/kg/day or less for one year; 12-month FVC difference 2.53 percent, P less than 0.03.
   • Nintedanib 150 mg twice daily — SENSCIS: FVC −52.4 versus −93.3 mL per year (difference 41.0 mL, P=0.04); 48.4 percent were already on mycophenolate. INBUILD is progressive fibrosing ILD other than IPF with 24-month eligibility — that window is not the ATS 2022 PPF definition (at least two of three criteria in the past year). ^{[6][5][4][3][1]}

2. Pulmonary hypertension management:

   • Complete right heart catheterisation to separate Group 1 PAH from Group 3 PH due to ILD
   • Named vasodilators (ambrisentan, sildenafil, riociguat) and RISE-IIP/INSTAGE labels are exam convention, not 2022 ATS questions. Refer to a PH-MDT. ^[1]

3. Oxygen therapy:

   • Correct documented hypoxaemia. Named PaO2 / SpO2 / hours-per-day LTOT bands are BTS/NICE service convention, not trial end-points in the papers cited here. ^[1]

4. Gastrointestinal management:

   • PPI for SSc oesophageal disease is reasonable comorbidity care. It is not IPF disease-modifying therapy — ATS 2022 is conditionally against antacid medication and antireflux surgery for treating IPF. ^[1]

5. Raynaud and digital vascular disease:

   • Continue the calcium channel blocker. Named PDE5 / bosentan ulcer-prevention regimens are exam convention, not end-points in SENSCIS or SLS. ^[5]

6. Renal surveillance:

   • Blood pressure and renal surveillance for scleroderma renal crisis is exam convention, not a SENSCIS end-point. Do not invent a sourced prednisolone 15 mg/day threshold from these abstracts. Avoid PANTHER combination immunosuppression (that trial is IPF harm: 8 versus 1 deaths). ^[5][7]

7. General measures:

   • Pulmonary rehabilitation (a 6-to-8-week duration is exam convention)
   • Vaccinations
   • Nutritional support
   • Early transplant discussion and advance care planning — named FVC/DLCO referral cut-offs are not in the cited abstracts ^[1]

Examiner discussion questions

Q: "Why does she have a disproportionately reduced DLCO?" ^[5]

"The DLCO of 40 percent is lower than the FVC of 62 percent would lead you to expect from volume loss alone. In systemic sclerosis this pattern raises overlapping pulmonary hypertension until catheterised — SENSCIS does not give a sourced DLCO cut-off, so I would not invent one. Echo RVSP 52 mmHg is a flag, not a diagnosis. Right heart catheterisation characterises the haemodynamics and separates Group 1 from Group 3." ^[5]

Q: "How does her scleroderma renal crisis risk influence your drug choices?" ^[6][7]

"I would not use high-dose corticosteroids as SSc-ILD disease-modifying therapy, and I would not import PANTHER combination prednisone–azathioprine–NAC (IPF harm: 8 versus 1 deaths, 23 versus 7 hospitalisations). Immunosuppression here is mycophenolate 1500 mg twice daily (SLS II: prefer for tolerability, primary endpoint p=0.24). A sourced prednisolone 15 mg/day renal-crisis threshold is not in the SENSCIS or SLS abstracts and is labelled exam convention. Blood-pressure surveillance remains exam teaching, not a trial end-point." ^[6][7][5]

Q: "What is the prognosis?" ^[5][9]

"SENSCIS: ILD is a leading cause of systemic sclerosis-related death. Do not quote an unsourced 3-year 40–50 percent PAH survival band from these papers. For IPF, Ley reports an overall poor prognosis and GAP 1-year mortality 6 / 16 / 39 percent — that index is for IPF, not SSc-ILD. Her integrated care needs an ILD-MDT plus a PH-MDT: mycophenolate for tolerability, nintedanib when the fibrotic phenotype is progressing (SENSCIS), and catheter-guided PH decisions. ATS 2022 PPF is ≥2 of 3 in the past year in an ILD other than IPF — if she later meets that, nintedanib is conditionally recommended; INBUILD’s 24 months is eligibility, not the PPF definition." ^[5][9][1][3]