Velcro-type crackles

Specialty: Respiratory.

• dry crackling rales
• velcro type rails
• cellophane crackles

Why it occurs

• Idiopathic pulmonary fibrosis (IPF) (fine-pitched dry crackles, audible mainly at the end of inspiration at the bases of the lungs, similar to the sound of slowly separating a Velcro strip, caused by the sudden opening of collapsed alveoli and bronchioles surrounded by rigid, fibrous interstitial tissue)
• Nonspecific interstitial pneumonia (IIP) associated with scleroderma or dermatomyositis
• Asbestosis (pneumoconiosis due to inhalation of asbestos fibers with pleural and basal parenchymal fibrosis)
• Pneumonitis due to chronic hypersensitivity in established fibrotic phase
• Pulmonary toxicity due to antifibrotic or chemotherapy drugs (such as amiodarone, bleomycin or long-term methotrexate).

Initial workup

High-resolution chest computed tomography (CT) (HRCT) (essential to document the pattern of usual interstitial pneumonia - UIP, characterized by honeycombing, traction bronchiectasis and basal reticulation); Forced spirometry and diffusing capacity for carbon monoxide (DLCO); Baseline arterial blood gas and after stress test.

Standard management

• Nintedanib — 150 mg orally every 12 hours in IPF or progressive fibrosing interstitial lung disease to slow the decline in FVC
• Pirfenidone — 801 mg orally every 8 hours
• Prednisone (0.5 mg/kg/day orally if there is a predominant active inflammatory component in connective tissue diseases, monitoring long-term side effects).