# Respiratory disease

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Disease of the respiratory system

Medical condition

Respiratory disease Micrograph of an emphysematous lung; emphysema is a respiratory disease, strongly associated with smoking. H&E stain. Specialty Pulmonology

**Respiratory diseases**, or **lung diseases**,[1] are [pathological](/source/Pathology) conditions affecting the organs and tissues that make [gas exchange](/source/Gas_exchange) difficult in [air-breathing](/source/Breathing) animals. They include conditions of the [respiratory tract](/source/Respiratory_tract) including the [trachea](/source/Trachea), [bronchi](/source/Bronchi), [bronchioles](/source/Bronchioles), [alveoli](/source/Pulmonary_alveolus), [pleurae](/source/Pulmonary_pleurae), [pleural cavity](/source/Pleural_cavity), the nerves and [muscles of respiration](/source/Muscles_of_respiration). Respiratory diseases range from mild and self-limiting, such as the [common cold](/source/Common_cold), [influenza](/source/Influenza), and [pharyngitis](/source/Pharyngitis) to life-threatening [diseases](/source/Disease) such as [bacterial pneumonia](/source/Bacterial_pneumonia), [pulmonary embolism](/source/Pulmonary_embolism), [tuberculosis](/source/Tuberculosis), [acute asthma](/source/Asthma), [lung cancer](/source/Lung_cancer),[2] [chronic obstructive pulmonary disease](/source/Chronic_obstructive_pulmonary_disease) and [severe acute respiratory syndromes](/source/Severe_acute_respiratory_syndrome), such as [COVID-19](/source/Coronavirus_disease_2019).[3] Respiratory diseases can be classified in many different ways, including by the organ or tissue involved, by the type and pattern of associated signs and symptoms, or by the cause of the disease.

The study of respiratory disease is known as [pulmonology](/source/Pulmonology). A [physician](/source/Physician) who specializes in respiratory disease is known as a pulmonologist, a chest medicine specialist, a respiratory medicine specialist, a respirologist or a thoracic medicine specialist.

## Obstructive lung disease

[Asthma](/source/Asthma), [chronic bronchitis](/source/Bronchitis#Chronic_bronchitis), [bronchiectasis](/source/Bronchiectasis) and [chronic obstructive pulmonary disease](/source/Chronic_obstructive_pulmonary_disease) (COPD) are all [obstructive lung diseases](/source/Obstructive_lung_disease) characterised by [airway obstruction](/source/Airway_obstruction). This limits the amount of air that is able to enter alveoli because of constriction of the bronchial tree, due to inflammation. Obstructive lung diseases are often identified because of symptoms and diagnosed with [pulmonary function tests](/source/Pulmonary_function_tests) such as [spirometry](/source/Spirometry). Many obstructive lung diseases are managed by avoiding triggers (such as [dust mites](/source/Dust_mite) or [smoking](/source/Smoking)), with symptom control such as [bronchodilators](/source/Bronchodilator), and with suppression of inflammation (such as through [corticosteroids](/source/Corticosteroid)) in severe cases. One common cause of COPD including [emphysema](/source/Emphysema), and chronic bronchitis, is [tobacco smoking](/source/Tobacco_smoking), and common causes of [bronchiectasis](/source/Bronchiectasis) include severe infections and [cystic fibrosis](/source/Cystic_fibrosis). The definitive cause of [asthma](/source/Asthma) is not yet known.[4]

## Restrictive lung diseases

[Age-standardised](/source/Age_adjustment) [disability-adjusted life year](/source/Disability-adjusted_life_year) (DALY) rates from respiratory diseases by country (per 100,000 inhabitants).

[Restrictive lung diseases](/source/Restrictive_lung_disease) are a category of respiratory diseases characterized by a loss of [lung compliance](/source/Pulmonary_compliance), causing incomplete lung expansion and increased lung stiffness, such as in infants with respiratory distress syndrome.[5] Restrictive lung diseases can be divided into two categories: those caused by intrinsic factors and those caused by extrinsic factors.[6] Restrictive lung diseases yielding from intrinsic factors occur within the lungs themselves, such as [tissue death](/source/Tissue_death) due to inflammation or toxins. Conversely, restrictive lung diseases caused by extrinsic factors result from conditions originating from outside the lungs such as [neuromuscular dysfunction](/source/Neuromuscular_disease) and irregular chest wall movements.[6]

## Chronic respiratory disease

Chronic respiratory diseases are long-term diseases of the airways and other structures of the lung. They are characterized by a high inflammatory cell recruitment ([neutrophil](/source/Neutrophil_granulocyte)) and/or destructive cycle of [infection](/source/Infection), (e.g. mediated by *[Pseudomonas aeruginosa](/source/Pseudomonas_aeruginosa)*). Some of the most common are [asthma](/source/Asthma), [chronic obstructive pulmonary disease](/source/Chronic_obstructive_pulmonary_disease), and [acute respiratory distress syndrome](/source/Acute_respiratory_distress_syndrome). Most chronic respiratory diseases are not curable; however, various forms of treatment that help dilate major air passages and improve [shortness of breath](/source/Shortness_of_breath) can help control symptoms and increase the quality of life.[7]

### Telerehabilitation for chronic respiratory disease

The latest evidence suggests that primary pulmonary rehabilitation and maintenance rehabilitation delivered through telerehabilitation for people with chronic respiratory disease reaches outcomes similar to centre-based rehabilitation.[8] While there are no safety issues identified, the findings are based on evidence limited by a small number of studies.[8]

## Respiratory tract infections

Infections can affect any part of the respiratory system. They are traditionally divided into upper respiratory tract infections and lower respiratory tract infections.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

### Upper respiratory tract infection

Classic steeple sign indicating croup

The upper airway is defined as all the structures connecting the glottis to the mouth and nose.[9] The most common [upper respiratory tract infection](/source/Upper_respiratory_tract_infection) is the [common cold](/source/Common_cold). However, infections of specific organs of the upper respiratory tract such as [sinusitis](/source/Sinusitis), [tonsillitis](/source/Tonsillitis), [otitis media](/source/Otitis_media), [pharyngitis](/source/Pharyngitis) and [laryngitis](/source/Laryngitis) are also considered upper respiratory tract infections.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

[Epiglottitis](/source/Epiglottitis) is a bacterial infection of the larynx which causes life-threatening swelling of the [epiglottis](/source/Epiglottis) with a mortality rate of 7% in adults and 1% in children.[10] *[Haemophilus influenzae](/source/Haemophilus_influenzae)* is still the primary cause even with vaccinations. Also Streptococcus pyogenes can cause epiglottitis. Symptoms include drooling, stridor, difficulty breathing and swallowing, and a hoarse voice.[11]

[Croup](/source/Croup) (Laryngotracheobronchitis) is a viral infection of the [vocal cords](/source/Vocal_cords) typically lasting five to six days. The main symptom is a barking cough and low-grade [fever](/source/Fever). On an X-ray, croup can be recognized by the "steeple sign", which is a narrowing of the [trachea](/source/Trachea). It most commonly occurs in winter months in children between the ages of 3 months and 5 years. A severe form caused by bacteria is called bacterial tracheitis.[12]

[Tonsillitis](/source/Tonsillitis) is swelling of the tonsils by a bacterial or viral infection. This inflammation can lead to airway obstruction. From tonsillitis can come a peritonsillar abscess which is the most common upper airway infection and occurs primarily in young adults. It causes swelling in one of the tonsils, pushing the [uvula](/source/Palatine_uvula) to the unaffected side.[9] Diagnosis is usually made based on the presentation and examination. Symptoms generally include fever, sore throat, trouble swallowing, and sounding like they have a "hot potato" in their mouth.[13]

### Lower respiratory tract infection

The most common lower respiratory tract infection is [pneumonia](/source/Pneumonia), an infection of the lungs which is usually caused by bacteria, particularly *[Streptococcus pneumoniae](/source/Streptococcus_pneumoniae)* in Western countries. Worldwide, [tuberculosis](/source/Tuberculosis) is an important cause of pneumonia. Other pathogens such as [viruses](/source/Virus) and fungi can cause pneumonia, for example [severe acute respiratory syndrome](/source/Severe_acute_respiratory_syndrome), [COVID-19](/source/COVID-19) and [pneumocystis pneumonia](/source/Pneumocystis_pneumonia). Pneumonia may develop complications such as a lung abscess, a round cavity in the lung caused by the infection, or may spread to the [pleural cavity](/source/Pleural_cavity).[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

Poor oral care may be a contributing factor to lower respiratory disease, as bacteria from gum disease may travel through airways and into the lungs.[14][15] There is also a co-occurrence between [acute eosinophilic pneumonia](/source/Acute_eosinophilic_pneumonia), [desquamative interstitial pneumonia](/source/Desquamative_interstitial_pneumonia) and tobacco use.[16]

### Upper and lower respiratory tract infection

[Primary ciliary dyskinesia](/source/Primary_ciliary_dyskinesia) is a genetic disorder causing the cilia to not move in a coordinated manner. This causes chronic respiratory infections, cough, and nasal congestion. This can lead to bronchiectasis, which can cause life-threatening breathing issues.[17]

## Tumors

### Malignant tumors

Malignant tumors of the respiratory system, particularly [primary carcinomas of the lung](/source/Lung_cancer), are a major health problem responsible for 15% of all cancer diagnoses and 30% of all cancer deaths. The majority of respiratory system cancers are attributable to [smoking tobacco](/source/Tobacco_smoking).[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

The major [histological](/source/Histology) types of respiratory system cancer are:[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

- [Small cell lung cancer](/source/Small_cell_lung_cancer)

- [Non-small cell lung cancer](/source/Non-small_cell_lung_cancer) - Adenocarcinoma of the lung - Squamous cell carcinoma of the lung - Large cell lung carcinoma

- Other lung cancers ([carcinoid](/source/Carcinoid), [Kaposi's sarcoma](/source/Kaposi's_sarcoma), [melanoma](/source/Melanoma))

- [Lymphoma](/source/Lymphoma)

- [Head and neck cancer](/source/Head_and_neck_cancer)

- [Pleural](/source/Pleural) [mesothelioma](/source/Mesothelioma), almost always caused by exposure to [asbestos](/source/Asbestos) dust.

In addition, since many cancers spread via the bloodstream and the entire cardiac output passes through the lungs, it is common for cancer [metastases](/source/Metastases) to occur within the lung. [Breast cancer](/source/Breast_cancer) may invade directly through local spread, and through lymph node metastases. After metastasis to the [liver](/source/Liver_cancer), [colon cancer](/source/Colon_cancer) frequently metastasizes to the lung. [Prostate cancer](/source/Prostate_cancer), germ cell cancer and [renal cell carcinoma](/source/Renal_cell_carcinoma) may also metastasize to the lung.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

Treatment of respiratory system cancer depends on the type of cancer. Surgical removal of part of a lung ([lobectomy](/source/Lobectomy), [segmentectomy](/source/Segmentectomy), or [wedge resection](/source/Wedge_resection)) or of an entire lung ([pneumonectomy](/source/Pneumonectomy)), along with chemotherapy and [radiotherapy](/source/Radiotherapy), are all used. The chance of surviving lung cancer depends on the cancer stage at the time the cancer is diagnosed, and to some extent on the [histology](/source/Histology), and is only about 14–17% overall. In the case of metastases to the lung, treatment can occasionally be curative but only in certain, rare circumstances.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

### Benign tumors

Benign tumors are relatively rare causes of respiratory disease. Examples of benign tumors are:[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

- Pulmonary [hamartoma](/source/Hamartoma)

- Congenital malformations such as [pulmonary sequestration](/source/Pulmonary_sequestration) and [congenital cystic adenomatoid malformation](/source/Congenital_cystic_adenomatoid_malformation) (CCAM).

## Pleural cavity diseases

Pleural cavity diseases include [pleural mesothelioma](/source/Pleural) which are mentioned above.

A collection of fluid in the pleural cavity is known as a [pleural effusion](/source/Pleural_effusion).[18] This may be due to fluid shifting from the bloodstream into the pleural cavity due to conditions such as congestive heart failure and cirrhosis.[18] It may also be due to inflammation of the pleura itself as can occur with infection, [pulmonary embolus](/source/Pulmonary_embolus), tuberculosis, mesothelioma and other conditions.[18]

A [pneumothorax](/source/Pneumothorax) is a hole in the pleura covering the lung allowing air in the lung to escape into the pleural cavity. The affected lung "collapses" like a deflated balloon. A [tension pneumothorax](/source/Tension_pneumothorax) is a particularly severe form of this condition where the air in the pleural cavity cannot escape, so the pneumothorax keeps getting bigger until it compresses the heart and blood vessels, leading to a life-threatening situation.

## Pulmonary vascular disease

Pulmonary vascular diseases are conditions that affect the [pulmonary circulation](/source/Pulmonary_circulation). Examples are:[19][*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

- [Pulmonary embolism](/source/Pulmonary_embolism), a [blood clot](/source/Thrombosis) that forms in a vein, breaks free, travels through the heart and lodges in the lungs (thromboembolism). Large pulmonary emboli are fatal, causing sudden death. A number of other substances can also embolise (travel through the blood stream) to the lungs but they are much more rare: [fat embolism](/source/Fat_embolism) (particularly after bony injury), amniotic fluid embolism (with complications of labour and delivery), [air embolism](/source/Air_embolism) ([iatrogenic](/source/Iatrogenic) – caused by invasive medical procedures).

- [Pulmonary arterial hypertension](/source/Pulmonary_arterial_hypertension), elevated pressure in the pulmonary arteries. Most commonly it is [idiopathic](/source/Idiopathic) (i.e. of unknown cause) but it can be due to the effects of another disease, particularly COPD. This can lead to strain on the right side of the heart, a condition known as [cor pulmonale](/source/Cor_pulmonale).

- [Pulmonary edema](/source/Pulmonary_edema), leakage of fluid from capillaries of the lung into the [alveoli](/source/Pulmonary_alveolus) (or air spaces). It is usually due to congestive heart failure.

- Pulmonary hemorrhage, inflammation and damage to capillaries in the lung resulting in blood leaking into the alveoli. This may cause blood to be coughed up. Pulmonary hemorrhage can be due to auto-immune disorders such as [granulomatosis with polyangiitis](/source/Granulomatosis_with_polyangiitis) and [Goodpasture's syndrome](/source/Goodpasture's_syndrome).

## Neonatal diseases

Pulmonary diseases also impact newborns and the disorders are often unique from those that affect adults.

[Infant respiratory distress syndrome](/source/Infant_respiratory_distress_syndrome) most commonly occurs in less than six hours after birth in about 1% of all births in the United States.[9] The main risk factor is prematurity with the likelihood of it occurring going up to 71% in infants under 750g.[20] Other risk factors include infant of a diabetic mother (IDM), method of delivery, fetal asphyxia, genetics, [prolonged rupture of membranes](/source/Prelabor_rupture_of_membranes) (PROM), maternal toxemia, [chorioamnionitis](/source/Chorioamnionitis), and male sex. The widely accepted pathophysiology of respiratory distress syndrome is it caused by insufficient surfactant production and immature lung and vascular development. The lack of surfactant makes the lungs [atelectatic](/source/Atelectasis) causing a ventilation to perfusion mismatch, lowered compliance, and increased air resistance. This causes hypoxia and respiratory acidosis which can lead to [pulmonary hypertension](/source/Pulmonary_hypertension). It has a ground glass appearance on an x-ray. Symptoms can include tachypnea, nasal flaring, paradoxical chest movement, grunting, and subcostal retractions.[9]

[Bronchopulmonary Dysplasia](/source/Bronchopulmonary_dysplasia) is a condition that occurs after birth usually from [mechanical ventilation](/source/Mechanical_ventilation) and oxygen use. It happens almost exclusively in pre-mature infants and is characterized by the alveoli, and lung vasculature becoming inflamed and damaged. Complications from BPD can follow a patient into adulthood. As a child they may experience learning disabilities, pulmonary hypertension, and hearing problems. As an adult, there is an increased likelihood for asthma and exercise intolerance.[21]

[Meconium Aspiration Syndrome](/source/Meconium_aspiration_syndrome) occurs in full term or post-term infants who aspirate [meconium](/source/Meconium). Risk factors include a diabetic mother, fetal hypoxia, precipitous delivery, and maternal high blood pressure.[22] Its diagnosis is based on meconium stained amniotic fluid at delivery and staining on the skin, nails, and umbilical cord. Aspiration can cause airway obstruction, air-trapping, pneumonia, lung inflammation, and inactivated surfactant. It presents as patchy atelectasis and hyperinflation on an x-ray with a [pneumothorax](/source/Pneumothorax) of pneumomediastinum also possible.[9]

[Persistent Pulmonary Hypertension of the Newborn](/source/Persistent_fetal_circulation) (PPHN) is a syndrome that occurs from an abnormal transition to extra-uterine life. It is marked by an elevated pulmonary vascular resistance and vasoconstriction causing a right-to-left shunt of the blood through the [foramen ovale](/source/Foramen_ovale_(heart)) or [ductus arteriosus](/source/Patent_ductus_arteriosus).[9] There are three main causes of PPHN are parenchymal diseases such as meconium aspiration syndrome, idiopathic, and hypoplastic vasculature like in a diaphragmatic hernia. It will eventually resolve in most infants.[23] This is the only syndrome that inhaled nitric oxide is approved for by the FDA.[24]

Pulmonary interstitial emphysema

[Transient Tachypnea of the Newborn](/source/Transient_tachypnea_of_the_newborn) is caused by the retention of alveolar fluid in the lungs. It commonly occurs in infants who are delivered via [caesarean section](/source/Caesarean_section) without the onset of labor because absorption of amniotic fluid in the lungs has not yet commenced. Other risk factors are male sex, [macrosomia](/source/Large_for_gestational_age), multiple gestations, and maternal asthma. It usually presents with tachypnea and increased work of breathing. On an x-ray diffuse infiltrates, interlobar fissures, and sometimes [pleural effusions](/source/Pleural_effusion) can be seen. It is a diagnosis of exclusion because of its similarity to other diseases and frequently CPAP is used to help push the lung fluid into the pulmonary vasculature.[9][25]

[Pulmonary interstitial emphysema](/source/Pulmonary_interstitial_emphysema) is the condition of air escaping overdistended alveoli into the pulmonary interstitium. It is a rare disease that occurs most often in premature infants, even though it is possible to appear in adults.[26] It often presents as a slow deterioration with the need for increased ventilatory support. Chest x-ray is the standard for diagnosis where it is seen as linear or cystic translucencies extending to the edges of the lungs.[9]

[Bronchiolitis](/source/Bronchiolitis) is the swelling and buildup of mucus in the bronchioles. It is usually caused by [respiratory syncytial virus](/source/Respiratory_syncytial_virus) (RSV), which is spread when an infant touches the nose or throat fluids of someone infected.[27] The virus infects the cells causing ciliary dysfunction and death. The debris, edema, and inflammation eventually leads to the symptoms.[28] It is the most common reason for admission of children under the age of one year. It can present widely from a mild respiratory infection to respiratory failure. Since there is no medication to treat the disease, it is only managed supportively with fluids and oxygen.[29]

## Diagnosis

Respiratory diseases may be investigated by performing one or more of the following tests:[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

- [Biomarker](/source/Biomarker) tests

- [Biopsy](/source/Biopsy) of the lung or pleura

- [Blood test](/source/Blood_test)

- [Bronchoscopy](/source/Bronchoscopy)

- [Chest X-ray](/source/Chest_X-ray)

- [CT scan](/source/CT_scan), including [high-resolution computed tomography](/source/High-resolution_computed_tomography)

- [Culture of microorganisms](/source/Microbiological_culture) from secretions such as sputum

- [Ultrasound](/source/Medical_ultrasonography) scanning can be useful to detect fluid such as [pleural effusion](/source/Pleural_effusion)

- [Pulmonary function test](/source/Pulmonary_function_test)

- [Ventilation–perfusion scan](/source/Ventilation%2Fperfusion_scan)

## Epidemiology

Respiratory disease death rate

Respiratory disease is a common and significant cause of illness and death around the world. In the US, approximately one billion [common colds](/source/Common_colds) occur each year.[30] A study found that in 2010, there were approximately 6.8 million emergency department visits for respiratory disorders in the U.S. for patients under the age of 18.[31] In 2012, respiratory conditions were the most frequent reasons for hospital stays among children.[32]

In the UK, approximately 1 in 7 individuals are affected by some form of chronic lung disease, most commonly [chronic obstructive pulmonary disease](/source/Chronic_obstructive_pulmonary_disease), which includes [asthma](/source/Asthma), [chronic bronchitis](/source/Bronchitis#Chronic_bronchitis) and [emphysema](/source/Emphysema).[33] Respiratory diseases (including lung cancer) are responsible for over 10% of hospitalizations and over 16% of deaths in Canada.[34]

In 2011, respiratory disease with ventilator support accounted for 93.3% of ICU utilization in the United States.[35]

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## External links

Wikimedia Commons has media related to [Diseases and disorders of the respiratory system](https://commons.wikimedia.org/wiki/Category:Diseases_and_disorders_of_the_respiratory_system).

Classification D ICD-10: J00-J99 ICD-9-CM: 460-519 MeSH: D012140

v t e Diseases of the respiratory system Upper RT (including URTIs, common cold) Head sinuses Sinusitis nose Rhinitis Vasomotor rhinitis Atrophic rhinitis Hay fever Nasal polyp Rhinorrhea nasal septum Nasal septum deviation Nasal septum perforation Cocaine-induced midline destructive lesions (CIMDL) Nasal septal hematoma tonsil Tonsillitis Adenoid hypertrophy Peritonsillar abscess Neck pharynx Pharyngitis Strep throat Laryngopharyngeal reflux (LPR) Retropharyngeal abscess larynx Croup Laryngomalacia Laryngeal cyst Laryngitis Laryngopharyngeal reflux (LPR) Laryngospasm vocal cords Laryngopharyngeal reflux (LPR) Vocal fold nodule Vocal fold paresis Vocal cord dysfunction epiglottis Epiglottitis trachea Tracheitis Laryngotracheal stenosis Lower RT/ lung disease (including LRTIs) Bronchial/ obstructive acute Acute bronchitis chronic COPD Chronic bronchitis Acute exacerbation of COPD) Asthma (Status asthmaticus AERD Exercise-induced Bronchiectasis Cystic fibrosis unspecified Bronchitis Bronchiolitis Bronchiolitis obliterans Diffuse panbronchiolitis Interstitial/ restrictive (fibrosis) External agents/ occupational lung disease Pneumoconiosis Aluminosis Asbestosis Baritosis Bauxite fibrosis Berylliosis Caplan's syndrome Chalicosis Coalworker's pneumoconiosis Siderosis Silicosis Talcosis Byssinosis Hypersensitivity pneumonitis Bagassosis Bird fancier's lung Farmer's lung Lycoperdonosis Other ARDS Combined pulmonary fibrosis and emphysema Pulmonary edema Löffler's syndrome/Eosinophilic pneumonia Respiratory hypersensitivity Allergic bronchopulmonary aspergillosis Hamman–Rich syndrome Idiopathic pulmonary fibrosis Sarcoidosis Vaping-associated pulmonary injury Obstructive / Restrictive Pneumonia/ pneumonitis By pathogen Viral Bacterial Pneumococcal Klebsiella Atypical bacterial Mycoplasma Legionnaires' disease Chlamydiae Fungal Pneumocystis Parasitic noninfectious Chemical/Mendelson's syndrome Aspiration/Lipid By vector/route Community-acquired Healthcare-associated Hospital-acquired By distribution Broncho- Lobar IIP UIP DIP BOOP-COP NSIP RB Other Atelectasis circulatory Pulmonary hypertension Pulmonary embolism Lung abscess Pleural cavity/ mediastinum Pleural disease Pleuritis/pleurisy Pneumothorax/Hemopneumothorax Pleural effusion Hemothorax Hydrothorax Chylothorax Empyema/pyothorax Malignant Fibrothorax Mediastinal disease Mediastinitis Mediastinal emphysema Other/general Respiratory failure Influenza Common cold SARS MERS COVID-19 Idiopathic pulmonary haemosiderosis Pulmonary alveolar proteinosis Tuberculosis

v t e Conditions originating in the perinatal period / fetal disease Maternal factors complicating pregnancy, labour or delivery placenta Placenta praevia Placental insufficiency Twin-to-twin transfusion syndrome chorion/amnion Chorioamnionitis umbilical cord Umbilical cord prolapse Nuchal cord Single umbilical artery presentation Breech birth Asynclitism Shoulder presentation Growth Small for gestational age / Large for gestational age Preterm birth / Postterm pregnancy Intrauterine growth restriction Birth trauma scalp Cephalohematoma Chignon Caput succedaneum Subgaleal hemorrhage Brachial plexus injury Erb's palsy Klumpke paralysis Affected systems Respiratory Intrauterine hypoxia Infant respiratory distress syndrome Transient tachypnea of the newborn Meconium aspiration syndrome Pleural disease Pneumothorax Pneumomediastinum Wilson–Mikity syndrome Bronchopulmonary dysplasia Cardiovascular Pneumopericardium Persistent fetal circulation Bleeding and hematologic disease Vitamin K deficiency bleeding HDN ABO Anti-Kell Rh c Rh D Rh E Hydrops fetalis Hyperbilirubinemia Bilirubin encephalopathy Neonatal jaundice Velamentous cord insertion Intraventricular hemorrhage Germinal matrix hemorrhage Anemia of prematurity Gastrointestinal Ileus Necrotizing enterocolitis Meconium peritonitis Integument and thermoregulation Erythema toxicum Sclerema neonatorum Nervous system Perinatal asphyxia Periventricular leukomalacia Musculoskeletal Gray baby syndrome muscle tone Congenital hypertonia Congenital hypotonia Infections Vertically transmitted infection Neonatal infection rubella herpes simplex mycoplasma hominis ureaplasma urealyticum Omphalitis Neonatal sepsis Group B streptococcal infection Neonatal conjunctivitis Other Miscarriage Perinatal mortality Stillbirth Infant mortality Neonatal withdrawal Fetal Alcohol Spectrum Disorder

v t e Respiratory physiology Respiration breath inhalation exhalation obligate nasal breathing respiratory rate respirometer pulmonary surfactant compliance elastic recoil hysteresivity airway resistance bronchial hyperresponsiveness constriction dilatation mechanical ventilation Control pons pneumotaxic center apneustic center medulla dorsal respiratory group ventral respiratory group chemoreceptors central peripheral pulmonary stretch receptor Hering–Breuer reflex Lung volumes VC FRC Vt dead space CC PEF calculations respiratory minute volume FEV1/FVC ratio Lung function tests spirometry body plethysmography peak flow meter nitrogen washout Circulation pulmonary circulation hypoxic pulmonary vasoconstriction pulmonary shunt Interactions ventilation (V) Perfusion (Q) Ventilation/perfusion ratio V/Q scan zones of the lung gas exchange pulmonary gas pressures alveolar gas equation alveolar–arterial gradient hemoglobin oxygen–hemoglobin dissociation curve (Oxygen saturation 2,3-BPG Bohr effect Haldane effect) carbonic anhydrase (chloride shift) oxyhemoglobin respiratory quotient arterial blood gas diffusion capacity (DLCO) Insufficiency high altitude death zone oxygen toxicity hypoxia

v t e Major disease groups Infection Parasitic disease Benign tumor Cancer Endocrine disease Malnutrition Metabolic disorder Immune disorder Hematologic disease Mental disorder Neurological disorder Eye disease Ear disease Cardiovascular disease Lymphatic disease Respiratory disease Maxillofacial disorder Gastrointestinal disease Urologic disease Female genital disease Breast disease Male genital disease Complications of pregnancy Obstetric labor complication Postpartum disorder Skin disease Musculoskeletal disorder Soft tissue disorder Connective tissue disease Bone disease Chondropathy Congenital disorder Fetal disease

Authority control databases National Japan Czech Republic 2 Israel Other NARA

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Adapted from the Wikipedia article [Respiratory disease](https://en.wikipedia.org/wiki/Respiratory_disease) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Respiratory_disease?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.