Respiratory disease encompasses any number of pathological conditions that affect the breathing system of a human being, including the upper respiratory tract, the trachea, bronchi, bronchioles, pleura, alveoli, and muscles used in breathing. Respiratory disease can be anything from a mild common cold to more serious lung cancer.
Inflammatory lung disease, such as asthma, cystic fibrosis, emphysema, or chronic obstructive pulmonary disorder, (COPD) is characterized by a high neutrophil count, excess white blood cells. Restrictive lung diseases cause incomplete lung expansion and lung stiffness, which can make breathing difficult.
Respiratory disease also includes several types of tract infections. Upper respiratory tract infections, the most common being a cold, involve the nose, throat (pharynx and larynx), and sinuses. Other upper respiratory tract infections include sinusitis, tonsillitis, laryngitis, and Otis media. Lower respiratory tract infections involve the lungs themselves, and may include pneumonia and tuberculosis.
Other forms of respiratory disease include malignant or benign tumors, pleural cavity diseases, and pulmonary vascular disease, such as a pulmonary embolism or pulmonary edema. One of the major causes of respiratory disease is smoking. This makes respiratory disease one of the deadliest, costliest, and most avoidable diseases to which human beings are subject.