Though idiopathic pulmonary fibrosis (IPF) is characterized by single-organ involvement, many comorbid conditions occur within other organ systems. Patients with IPF may present during evolution different complications and comorbidities that influence the prognosis and modify the natural course of their disease. In this chapter, we highlight common comorbid conditions encountered in IPF, discuss disease-specific diagnostic modalities, and review the current treatment data for several key comorbidities. The diagnosis and treatment of these comorbidities is a challenge for the pulmonologist specialized in interstitial lung diseases (ILDs). We will focus on pulmonary emphysema, lung cancer, gastroesophageal reflux, pulmonary hypertension, obstructive sleep apnea (sleep disorders), and acute exacerbation of IPF.

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.

The treatment of post-covid pulmonary fibrotic abnormalities remain a challenge in severe COVID19 survivors. Aims and Objectives: To evaluate the efficacy and safety profile of pirfenidone in subjects who present clinical-radiological signs of pulmonary fibrosis after severe SARS-COV2 pneumonia. Methods: Randomized multicenter double-blind phase-II placebo-controlled clinical trial that included patients with post-covid19 pulmonary fibrotic-like changes after at least one-month of hospital discharge. Patients received treatment for 6 months. The main endpoint was the rate of patients that improved (%FVC-change and high-resolution computed tomography (HRCT) fibrotic score). Results: 113 patienets were randomized. Most were male (74%), mean age 63.7 years and 50% had required tracheal intubation and mechanical ventilation during hospital stay. Mean HRCT-score was 20%(+/-14.8), mean FVC% 78(+/-19) and DLCO% 58.5(+/-19) at randomization, 49% required oxygen at home and 95% were receiving oral glucocorticoids. Although no statistically significant differences were found in the rate of patients that improved between groups, the mean percentage of FVC improvement was +12.74%(10.6) with pirfenidone and +4.35%(22) with placebo (p=0.06). Fibrotic-score reduction was -5.3% with pirfenidone and -2.5% with placebo. Clinically significant K-BILD score improvement was observed in 55% of pirfenidone patients and 39% of placebo (p=0.19). The presence of adverse events was not statistically different. Conclusions: Most patients with fibrotic-like changes after severe covid19 improve or stabilize in both arms, but the grade of improvement with pirfenidone over 24 weeks tends to be higher.