Acute Pulmonary Embolism *
Etiology Pulmonary embolism (PE) refers to blood clot(s) within the pulmonary arterial system, usually caused by migration of deep vein thrombosis (DVT) from the lower extremities. Rarely, emboli are from…
Hypersensitivity Pneumonitis
Etiology Hypersensitivity pneumonitis (HP), also known as extrinsic allergic alveolitis, is an immune-mediated inflammatory form of diffuse interstitial pulmonary disease caused by inhalation of various antigens that affect susceptible patients….
Sarcoidosis
Sarcoidosis is a systemic inflammatory disorder of unknown etiology that affects multiple organs and is characterized by the formation of noncaseating granulomas. Intrathoracic lymph node and pulmonary parenchymal involvement occurs…
Takayasu Arteritis
Etiology, Prevalence, and Epidemiology Takayasu arteritis, also known as pulseless disease or Martorell syndrome, is an idiopathic chronic granulomatous arteritis affecting medium and large arteries with a predilection for the…
Rheumatoid Arthritis
Etiology Rheumatoid arthritis (RA) is an autoimmune disorder of unknown cause with variable clinical manifestations. Genetic factors play a major role in disease susceptibility and expression. The B lymphocyte is…
Eosinophilic Lung Diseases
Eosinophilic diseases of the lung include a heterogeneous group of pulmonary disorders that characteristically feature peripheral or tissue eosinophilia. Patients with these illnesses have a variable clinical presentation and may…
Systemic Lupus Erythematosus
Etiology The pathogenesis of systemic lupus erythematosus (SLE) involves genetic and environmental factors, hormonal influences, and cell-mediated responses. In SLE, B lymphocytes lose self-tolerance and inappropriately produce autoantibodies. Serologic positivity…
Sjögren Syndrome
Etiology Sjögren’s syndrome, or “sicca syndrome,” is a disorder of the immune system that is largely defined by its two most common symptoms—dry eyes and a dry mouth; these symptoms…
Behçet Disease
Etiology, Prevalence, and Epidemiology Behçet disease is an uncommon systemic disorder of unknown etiology characterized by vasculitis and the triad of recurrent ulcers of the oral and genital mucosa with…
Interstitial Pneumonia With Autoimmune Features
Interstitial pneumonia with autoimmune features (IPAF) refers to the clinical entity of interstitial lung disease (ILD) in patients with features of autoimmunity but without overt connective tissue disease (CTD). IPAF…
