A 57 year old lady presents with progressively worsening exertional dyspnea for 1 year, associated with a non-productive cough, fatigue and small-joint arthralgia. She is otherwise asymptomatic and her medical, drug and family histories are unremarkable. She has never smoked and has no history of exposure to organic or inorganic dusts or environmental allergens. Her full blood count and CRP are normal, while her ESR is 50 mm/1h.
The chest x-ray shows bibasal reticulonodular opacities and bilaterally diminished lung volumes. The hila appear normal, while no pleural effusions are seen. The cardiac silhouette appears normal.
The HRCT shows bilateral patchy, predominantly subpleural and basal reticular opacities with associated traction bronchiectasis and honeycombing. A few areas of ground glass opacity are noted. No other abnormalities are noted.
The lung function tests show moderately severe restrictive lung disease with reduced total lung capacity, functional residual capacity and residual volume. The carbon monoxide diffusing capacity (DLCO) is diminished.
ANA - negative Ds-DNA - negative cANCA - negative pANCA - negative Rheumatoid factor - negative