Sputum: Material coughed up from the lungs and expectorated via the mouth. It contains MUCUS, cellular debris, and microorganisms. It may also contain blood or pus.Tuberculosis, Pulmonary: MYCOBACTERIUM infections of the lung.Bronchiectasis: Persistent abnormal dilatation of the bronchi.Cystic Fibrosis: An autosomal recessive genetic disease of the EXOCRINE GLANDS. It is caused by mutations in the gene encoding the CYSTIC FIBROSIS TRANSMEMBRANE CONDUCTANCE REGULATOR expressed in several organs including the LUNG, the PANCREAS, the BILIARY SYSTEM, and the SWEAT GLANDS. Cystic fibrosis is characterized by epithelial secretory dysfunction associated with ductal obstruction resulting in AIRWAY OBSTRUCTION; chronic RESPIRATORY INFECTIONS; PANCREATIC INSUFFICIENCY; maldigestion; salt depletion; and HEAT PROSTRATION.Bronchitis: Inflammation of the large airways in the lung including any part of the BRONCHI, from the PRIMARY BRONCHI to the TERTIARY BRONCHI.Mycobacterium tuberculosis: A species of gram-positive, aerobic bacteria that produces TUBERCULOSIS in humans, other primates, CATTLE; DOGS; and some other animals which have contact with humans. Growth tends to be in serpentine, cordlike masses in which the bacilli show a parallel orientation.Specimen Handling: Procedures for collecting, preserving, and transporting of specimens sufficiently stable to provide accurate and precise results suitable for clinical interpretation.Asthma: A form of bronchial disorder with three distinct components: airway hyper-responsiveness (RESPIRATORY HYPERSENSITIVITY), airway INFLAMMATION, and intermittent AIRWAY OBSTRUCTION. It is characterized by spasmodic contraction of airway smooth muscle, WHEEZING, and dyspnea (DYSPNEA, PAROXYSMAL).Eosinophils: Granular leukocytes with a nucleus that usually has two lobes connected by a slender thread of chromatin, and cytoplasm containing coarse, round granules that are uniform in size and stainable by eosin.Eosinophil Granule Proteins: Proteins found in EOSINOPHIL granules. They are primarily basic proteins that play a role in host defense and the proinflammatory actions of activated eosinophils.Forced Expiratory Volume: Measure of the maximum amount of air that can be expelled in a given number of seconds during a FORCED VITAL CAPACITY determination . It is usually given as FEV followed by a subscript indicating the number of seconds over which the measurement is made, although it is sometimes given as a percentage of forced vital capacity.Antitubercular Agents: Drugs used in the treatment of tuberculosis. They are divided into two main classes: "first-line" agents, those with the greatest efficacy and acceptable degrees of toxicity used successfully in the great majority of cases; and "second-line" drugs used in drug-resistant cases or those in which some other patient-related condition has compromised the effectiveness of primary therapy.Saline Solution, Hypertonic: Hypertonic sodium chloride solution. A solution having an osmotic pressure greater than that of physiologic salt solution (0.9 g NaCl in 100 ml purified water).Cough: A sudden, audible expulsion of air from the lungs through a partially closed glottis, preceded by inhalation. It is a protective response that serves to clear the trachea, bronchi, and/or lungs of irritants and secretions, or to prevent aspiration of foreign materials into the lungs.Expectorants: Agents that increase mucous excretion. Mucolytic agents, that is drugs that liquefy mucous secretions, are also included here.Bacteriological Techniques: Techniques used in studying bacteria.Suppuration: A pathologic process consisting in the formation of pus.Pulmonary Disease, Chronic Obstructive: A disease of chronic diffuse irreversible airflow obstruction. Subcategories of COPD include CHRONIC BRONCHITIS and PULMONARY EMPHYSEMA.Bronchoscopy: Endoscopic examination, therapy or surgery of the bronchi.Administration, Inhalation: The administration of drugs by the respiratory route. It includes insufflation into the respiratory tract.Tuberculosis: Any of the infectious diseases of man and other animals caused by species of MYCOBACTERIUM.Sensitivity and Specificity: Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)Leukocyte Count: The number of WHITE BLOOD CELLS per unit volume in venous BLOOD. A differential leukocyte count measures the relative numbers of the different types of white cells.Eosinophilia: Abnormal increase of EOSINOPHILS in the blood, tissues or organs.Respiratory Function Tests: Measurement of the various processes involved in the act of respiration: inspiration, expiration, oxygen and carbon dioxide exchange, lung volume and compliance, etc.Pseudomonas aeruginosa: A species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. aeruginosa is a major agent of nosocomial infection.Pseudomonas Infections: Infections with bacteria of the genus PSEUDOMONAS.Leukocyte Elastase: An enzyme that catalyzes the hydrolysis of proteins, including elastin. It cleaves preferentially bonds at the carboxyl side of Ala and Val, with greater specificity for Ala. EC 3.4.21.37.Tuberculosis, Multidrug-Resistant: Tuberculosis resistant to chemotherapy with two or more ANTITUBERCULAR AGENTS, including at least ISONIAZID and RIFAMPICIN. The problem of resistance is particularly troublesome in tuberculous OPPORTUNISTIC INFECTIONS associated with HIV INFECTIONS. It requires the use of second line drugs which are more toxic than the first line regimens. TB with isolates that have developed further resistance to at least three of the six classes of second line drugs is defined as EXTENSIVELY DRUG-RESISTANT TUBERCULOSIS.Microscopy: The use of instrumentation and techniques for visualizing material and details that cannot be seen by the unaided eye. It is usually done by enlarging images, transmitted by light or electron beams, with optical or magnetic lenses that magnify the entire image field. With scanning microscopy, images are generated by collecting output from the specimen in a point-by-point fashion, on a magnified scale, as it is scanned by a narrow beam of light or electrons, a laser, a conductive probe, or a topographical probe.Vital Capacity: The volume of air that is exhaled by a maximal expiration following a maximal inspiration.Lung Diseases, Obstructive: Any disorder marked by obstruction of conducting airways of the lung. AIRWAY OBSTRUCTION may be acute, chronic, intermittent, or persistent.Bronchial Provocation Tests: Tests involving inhalation of allergens (nebulized or in dust form), nebulized pharmacologically active solutions (e.g., histamine, methacholine), or control solutions, followed by assessment of respiratory function. These tests are used in the diagnosis of asthma.Cell Count: The number of CELLS of a specific kind, usually measured per unit volume or area of sample.Respiratory Tract Infections: Invasion of the host RESPIRATORY SYSTEM by microorganisms, usually leading to pathological processes or diseases.Diagnostic Techniques, Respiratory System: Methods and procedures for the diagnosis of diseases of the respiratory tract or its organs. It includes RESPIRATORY FUNCTION TESTS.