The benefits of a rapid diagnostic primary care circuit for interstitial lung disease

Interstitial lung diseases (ILDs) are complex rare diseases that associate a delay in diagnosis and eventually poor prognosis. Early and accurate diagnosis could be crucial. This study aimed to evaluate the feasibility and benefits of a rapid diagnostic circuit for ILD. A training program for ILD identification and a direct referral diagnostic circuit to the ILD Unit of University Hospital of Bellvitge were established in primary care centers in the southern metropolitan area of Barcelona (Spain). ILD patients were diagnosed and followed-up until study completion, death or lung transplantation. Diagnostic, therapeutic and prognostic outcomes were compared to patients referred through the common circuit during the same period of time. Of 123 patients referred directly from the primary care, 112 had ILD. The most common diagnosis were idiopathic pulmonary fibrosis and fibrotic hypersensitivity pneumonitis. The main reasons for suspecting ILD were interstitial radiological features (74%) and abnormal lung auscultation (67%). Eighteen patients were asymptomatic. Compared with patients referred through the common circuit, there was a statistically significant reduction in the time from symptom onset to diagnosis (6 vs. 22.1 months, p < 0.01) and in the percentage of fibrosing ILD (55.9 vs 63.9%, p 0.36). Although patients from rapid circuit were older, they had better forced vital capacity and diffusing capacity for carbon monoxide at diagnosis (p 0.04) and lung biopsies were performed more frequently. More patients were elegible for lung transplant. Identifying potential patients with fibrotic ILD through rapid circuit working with primary care physicians is feasible and useful.