Croup, also known as laryngotracheobronchitis, is a type of
respiratory infection
Respiratory tract infections (RTIs) are infectious diseases involving the respiratory tract. An infection of this type usually is further classified as an upper respiratory tract infection (URI or URTI) or a lower respiratory tract infection (LRI ...
that is usually caused by a
virus
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea.
Since Dmitri Ivanovsky's 1 ...
.
[ The infection leads to swelling inside the ]trachea
The trachea, also known as the windpipe, is a Cartilage, cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all air-breathing animals with lungs. The trachea extends ...
, which interferes with normal breathing and produces the classic symptoms of "barking/brassy" cough
A cough is a sudden expulsion of air through the large breathing passages that can help clear them of fluids, irritants, foreign particles and microbes. As a protective reflex, coughing can be repetitive with the cough reflex following three ph ...
, inspiratory stridor and a hoarse voice
A hoarse voice, also known as dysphonia or hoarseness, is when the voice involuntarily sounds breathy, raspy, or strained, or is softer in volume or lower in pitch. A hoarse voice, can be associated with a feeling of unease or scratchiness in the ...
.[ ]Fever
Fever, also referred to as pyrexia, is defined as having a body temperature, temperature above the human body temperature, normal range due to an increase in the body's temperature Human body temperature#Fever, set point. There is not a single ...
and runny nose
Rhinorrhea, rhinorrhoea, or informally runny nose is the free discharge of a thin mucus fluid from the nose; it is a common condition. It is a common symptom of allergies ( hay fever) or certain viral infections, such as the common cold or COVI ...
may also be present. These symptoms may be mild, moderate, or severe. Often it starts or is worse at night and normally lasts one to two days.[
Croup can be caused by a number of viruses including ]parainfluenza
Human parainfluenza viruses (HPIVs) are the viruses that cause human parainfluenza. HPIVs are a paraphyletic group of four distinct single-stranded RNA viruses belonging to the '' Paramyxoviridae'' family. These viruses are closely associated wit ...
and influenza virus
''Orthomyxoviridae'' (from Greek ὀρθός, ''orthós'' 'straight' + μύξα, ''mýxa'' 'mucus') is a family of negative-sense RNA viruses. It includes seven genera: ''Alphainfluenzavirus'', ''Betainfluenzavirus'', '' Gammainfluenzavirus'', ' ...
.[ Rarely is it due to a ]bacterial infection
Pathogenic bacteria are bacteria that can cause disease. This article focuses on the bacteria that are pathogenic to humans. Most species of bacteria are harmless and are often beneficial but others can cause infectious diseases. The number of ...
. Croup is typically diagnosed based on signs and symptoms after potentially more severe causes, such as epiglottitis
Epiglottitis is the inflammation of the epiglottis—the flap at the base of the tongue that prevents food entering the trachea (windpipe). Symptoms are usually rapid in onset and include trouble swallowing which can result in drooling, changes t ...
or an airway foreign body, have been ruled out.[ Further investigations, such as blood tests, ]X-rays
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 Picometre, picometers to 10 Nanometre, nanometers, corresponding to frequency, ...
and cultures, are usually not needed.
Many cases of croup are preventable by immunization
Immunization, or immunisation, is the process by which an individual's immune system becomes fortified against an infectious agent (known as the immunogen).
When this system is exposed to molecules that are foreign to the body, called ''non-sel ...
for influenza
Influenza, commonly known as "the flu", is an infectious disease caused by influenza viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These symptoms ...
and diphtheria
Diphtheria is an infection caused by the bacterium '' Corynebacterium diphtheriae''. Most infections are asymptomatic or have a mild clinical course, but in some outbreaks more than 10% of those diagnosed with the disease may die. Signs and s ...
.[ Most cases of croup are mild and the child can be treated at home with supportive care. Croup is usually treated with a single dose of ]steroids
A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and a ...
by mouth. In more severe cases inhaled epinephrine
Adrenaline, also known as epinephrine, is a hormone and medication which is involved in regulating visceral functions (e.g., respiration). It appears as a white microcrystalline granule. Adrenaline is normally produced by the adrenal glands and ...
may also be used.[ Hospitalization is required in one to five percent of cases.]
Croup is a relatively common condition that affects about 15% of children at some point.[ It most commonly occurs between six months and five years of age but may rarely be seen in children as old as fifteen.][ It is slightly more common in males than females.][ It occurs most often in autumn.][ Before ]vaccination
Vaccination is the administration of a vaccine to help the immune system develop immunity from a disease. Vaccines contain a microorganism or virus in a weakened, live or killed state, or proteins or toxins from the organism. In stimulating ...
, croup was frequently caused by diphtheria
Diphtheria is an infection caused by the bacterium '' Corynebacterium diphtheriae''. Most infections are asymptomatic or have a mild clinical course, but in some outbreaks more than 10% of those diagnosed with the disease may die. Signs and s ...
and was often fatal.[ This cause is now very rare in the ]Western world
The Western world, also known as the West, primarily refers to the various nations and state (polity), states in the regions of Europe, North America, and Oceania. due to the success of the diphtheria vaccine
Diphtheria vaccine is a toxoid vaccine against diphtheria, an illness caused by '' Corynebacterium diphtheriae''. Its use has resulted in a more than 90% decrease in number of cases globally between 1980 and 2000. The first dose is recommended ...
.
Signs and symptoms
Croup is characterized by a "barking" cough
A cough is a sudden expulsion of air through the large breathing passages that can help clear them of fluids, irritants, foreign particles and microbes. As a protective reflex, coughing can be repetitive with the cough reflex following three ph ...
, stridor, hoarseness
A hoarse voice, also known as dysphonia or hoarseness, is when the voice involuntarily sounds breathy, raspy, or strained, or is softer in volume or lower in pitch. A hoarse voice, can be associated with a feeling of unease or scratchiness in the ...
, and difficult breathing which usually worsens at night.[ The "barking" cough is often described as resembling the call of a ]sea lion
Sea lions are pinnipeds characterized by external ear flaps, long foreflippers, the ability to walk on all fours, short and thick hair, and a big chest and belly. Together with the fur seals, they make up the family Otariidae, eared seals. ...
.[ The stridor is worsened by agitation or ]crying
Crying is the dropping of tears (or welling of tears in the eyes) in response to an emotional state, or pain. Emotions that can lead to crying include sadness, anger, and even happiness. The act of crying has been defined as "a complex secr ...
, and if it can be heard at rest, it may indicate critical narrowing of the airways. As croup worsens, stridor may decrease considerably.[
Other symptoms include ]fever
Fever, also referred to as pyrexia, is defined as having a body temperature, temperature above the human body temperature, normal range due to an increase in the body's temperature Human body temperature#Fever, set point. There is not a single ...
, coryza
Rhinitis, also known as coryza, is irritation and inflammation of the Mucous membrane of nose, mucous membrane inside the human nose, nose. Common symptoms are a nasal congestion, stuffy nose, rhinorrhea, runny nose, sneeze, sneezing, and post- ...
(symptoms typical of the common cold
The common cold or the cold is a viral infectious disease of the upper respiratory tract that primarily affects the respiratory mucosa of the nose, throat, sinuses, and larynx. Signs and symptoms may appear fewer than two days after exposu ...
), and indrawing of the chest wall
The thoracic wall or chest wall is the boundary of the thoracic cavity.
Structure
The bone, bony human skeleton, skeletal part of the thoracic wall is the rib cage, and the rest is made up of muscle, skin, and fasciae.
The chest wall has 10 lay ...
–known as Hoover's sign. Drooling
Drooling, or slobbering, is the flow of saliva outside the mouth. Drooling can be caused by excess production of saliva, inability to retain saliva within the mouth (incontinence of saliva), or problems with swallowing (dysphagia or odynophagia ...
or a very sick appearance can indicate other medical conditions, such as epiglottitis
Epiglottitis is the inflammation of the epiglottis—the flap at the base of the tongue that prevents food entering the trachea (windpipe). Symptoms are usually rapid in onset and include trouble swallowing which can result in drooling, changes t ...
or tracheitis
Tracheitis is an inflammation of the trachea.
Although the trachea is usually considered part of the lower respiratory tract, in ICD-10 tracheitis is classified under "acute upper respiratory infections".
Symptoms
* Increasing deep or barking cr ...
.[
]
Causes
Croup is usually deemed to be due to a viral infection.[ Others use the term more broadly, to include acute laryngotracheitis (]laryngitis
Laryngitis is inflammation of the larynx (voice box). Symptoms often include a hoarse voice and may include fever, cough, pain in the front of the neck, and trouble swallowing. Typically, these last under two weeks.
Laryngitis is categorised ...
and tracheitis
Tracheitis is an inflammation of the trachea.
Although the trachea is usually considered part of the lower respiratory tract, in ICD-10 tracheitis is classified under "acute upper respiratory infections".
Symptoms
* Increasing deep or barking cr ...
together), spasmodic croup, laryngeal diphtheria, bacterial tracheitis, laryngotracheobronchitis, and laryngotracheobronchopneumonitis. The first two conditions involve a viral infection and are generally milder with respect to symptomatology; the last four are due to bacterial infection and are usually of greater severity.[
]
Viral
Viral croup or acute laryngotracheitis is most commonly caused by parainfluenza virus
Human parainfluenza viruses (HPIVs) are the viruses that cause human parainfluenza. HPIVs are a paraphyletic group of four distinct single-stranded RNA viruses belonging to the ''Paramyxoviridae'' family. These viruses are closely associated wit ...
(a member of the paramyxovirus family), primarily types 1 and 2, in 75% of cases.[ Other viral causes include ]influenza
Influenza, commonly known as "the flu", is an infectious disease caused by influenza viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These symptoms ...
A and B, measles
Measles is a highly contagious infectious disease caused by measles virus. Symptoms usually develop 10–12 days after exposure to an infected person and last 7–10 days. Initial symptoms typically include fever, often greater than , cough, ...
, adenovirus
Adenoviruses (members of the family ''Adenoviridae'') are medium-sized (90–100 nm), nonenveloped (without an outer lipid bilayer) viruses with an icosahedral nucleocapsid containing a double-stranded DNA genome. Their name derives from the ...
and respiratory syncytial virus
Respiratory syncytial virus (RSV), also called human respiratory syncytial virus (hRSV) and human orthopneumovirus, is a common, contagious virus that causes infections of the respiratory tract. It is a negative-sense, single-stranded RNA virus. ...
(RSV).[ Spasmodic croup is caused by the same group of viruses as acute laryngotracheitis, but lacks the usual signs of infection (such as fever, sore throat, and increased ]white blood cell count
A complete blood count (CBC), also known as a full blood count (FBC), is a set of medical laboratory tests that provide information about the cells in a person's blood. The CBC indicates the counts of white blood cells, red blood cells and pl ...
).[ Treatment, and response to treatment, are also similar.][
]
Bacteria and cocci
Croup caused by a bacterial infection is rare. Bacterial croup may be divided into laryngeal diphtheria, bacterial tracheitis, laryngotracheobronchitis, and laryngotracheobronchopneumonitis.[ Laryngeal diphtheria is due to '']Corynebacterium diphtheriae
''Corynebacterium diphtheriae'' is the pathogenic bacterium that causes diphtheria. It is also known as the Klebs–Löffler bacillus, because it was discovered in 1884 by German bacteriologists Edwin Klebs (1834–1912) and Friedrich Löffl ...
'' while bacterial tracheitis, laryngotracheobronchitis, and laryngotracheobronchopneumonitis are usually due to a primary viral infection with secondary bacterial growth. The most common cocci implicated are ''Staphylococcus aureus
''Staphylococcus aureus'' is a Gram-positive spherically shaped bacterium, a member of the Bacillota, and is a usual member of the microbiota of the body, frequently found in the upper respiratory tract and on the skin. It is often positive ...
'' and ''Streptococcus pneumoniae
''Streptococcus pneumoniae'', or pneumococcus, is a Gram-positive, spherical bacteria, alpha-hemolytic (under aerobic conditions) or beta-hemolytic (under anaerobic conditions), aerotolerant anaerobic member of the genus Streptococcus. They are ...
'', while the most common bacteria are ''Haemophilus influenzae
''Haemophilus influenzae'' (formerly called Pfeiffer's bacillus or ''Bacillus influenzae'') is a Gram-negative, non-motile, coccobacillary, facultatively anaerobic, capnophilic pathogenic bacterium of the family Pasteurellaceae. The bacteria ...
'', and ''Moraxella catarrhalis
''Moraxella catarrhalis'' is a fastidious, nonmotile, Gram-negative, aerobic, oxidase-positive diplococcus that can cause infections of the respiratory system, middle ear, eye, central nervous system, and joints of humans. It causes the infec ...
''.[
]
Pathophysiology
The viral infection that causes croup leads to swelling of the larynx
The larynx (), commonly called the voice box, is an organ in the top of the neck involved in breathing, producing sound and protecting the trachea against food aspiration. The opening of larynx into pharynx known as the laryngeal inlet is about ...
, trachea
The trachea, also known as the windpipe, is a Cartilage, cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all air-breathing animals with lungs. The trachea extends ...
, and large bronchi
A bronchus is a passage or airway in the lower respiratory tract that conducts air into the lungs. The first or primary bronchi pronounced (BRAN-KAI) to branch from the trachea at the carina are the right main bronchus and the left main bronchus. ...
[ due to infiltration of ]white blood cells
White blood cells, also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from mult ...
(especially histiocytes
A histiocyte is a vertebrate cell that is part of the mononuclear phagocyte system (also known as the reticuloendothelial system or lymphoreticular system). The mononuclear phagocytic system is part of the organism's immune system. The histiocyt ...
, lymphocytes
A lymphocyte is a type of white blood cell (leukocyte) in the immune system of most vertebrates. Lymphocytes include natural killer cells (which function in cell-mediated, cytotoxic innate immunity), T cells (for cell-mediated, cytotoxic adap ...
, plasma cells
Plasma cells, also called plasma B cells or effector B cells, are white blood cells that originate in the lymphoid organs as B lymphocytes and secrete large quantities of proteins called antibodies in response to being presented specific substan ...
, and neutrophils
Neutrophils (also known as neutrocytes or heterophils) are the most abundant type of granulocytes and make up 40% to 70% of all white blood cells in humans. They form an essential part of the innate immune system, with their functions varying in ...
).[ Swelling produces airway obstruction which, when significant, leads to dramatically increased work of breathing and the characteristic turbulent, noisy airflow known as stridor.][
]
Diagnosis
Croup is typically diagnosed based on signs and symptoms.[ The first step is to exclude other obstructive conditions of the upper airway, especially ]epiglottitis
Epiglottitis is the inflammation of the epiglottis—the flap at the base of the tongue that prevents food entering the trachea (windpipe). Symptoms are usually rapid in onset and include trouble swallowing which can result in drooling, changes t ...
, an airway foreign body
A foreign body (FB) is any object originating outside the body of an organism. In machinery, it can mean any unwanted intruding object.
Most references to foreign bodies involve propulsion through natural orifices into hollow organs.
Foreign bo ...
, subglottic stenosis, angioedema
Angioedema is an area of swelling ( edema) of the lower layer of skin and tissue just under the skin or mucous membranes. The swelling may occur in the face, tongue, larynx, abdomen, or arms and legs. Often it is associated with hives, which ...
, retropharyngeal abscess
Retropharyngeal abscess (RPA) is an abscess located in the tissues in the back of the throat behind the posterior pharyngeal wall (the retropharyngeal space). Because RPAs typically occur in deep tissue, they are difficult to diagnose by physical ...
, and bacterial tracheitis
Tracheitis is an inflammation of the trachea.
Although the trachea is usually considered part of the lower respiratory tract, in ICD-10 tracheitis is classified under "acute upper respiratory infections".
Symptoms
* Increasing deep or barking cro ...
.[
A frontal ]X-ray
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...
of the neck is not routinely performed,[ but if it is done, it may show a characteristic narrowing of the trachea, called the ]steeple sign
In radiology, the steeple sign is a radiologic sign found on a frontal neck radiograph where subglottic tracheal narrowing produces the shape of a church steeple within the trachea itself. The presence of the steeple sign supports a diagnosis of ...
, because of the subglottic stenosis, which resembles a steeple
In architecture, a steeple is a tall tower on a building, topped by a spire and often incorporating a belfry and other components. Steeples are very common on Christian churches and cathedrals and the use of the term generally connotes a religi ...
in shape. The steeple sign is suggestive of the diagnosis, but is absent in half of cases.[
Other investigations (such as ]blood test
A blood test is a laboratory analysis performed on a blood sample that is usually extracted from a vein in the arm using a hypodermic needle, or via fingerprick. Multiple tests for specific blood components, such as a glucose test or a cholester ...
s and viral culture
Viral culture is a laboratory technique in which samples of a virus are placed to different cell lines which the virus being tested for its ability to infect. If the cells show changes, known as cytopathic effects, then the culture is positive.
...
) are discouraged, as they may cause unnecessary agitation and thus worsen the stress on the compromised airway.[ While viral cultures, obtained via ]nasopharyngeal
The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struct ...
aspiration, can be used to confirm the exact cause, these are usually restricted to research settings.[ Bacterial infection should be considered if a person does not improve with standard treatment, at which point further investigations may be indicated.][
]
Severity
The most commonly used system for classifying the severity of croup is the Westley score. It is primarily used for research purposes rather than in clinical practice.[ It is the sum of points assigned for five factors: level of consciousness, cyanosis, stridor, air entry, and retractions.][ The points given for each factor is listed in the adjacent table, and the final score ranges from 0 to 17.][
* A total score of ≤ 2 indicates ''mild'' croup. The characteristic barking cough and hoarseness may be present, but there is no stridor at rest.][
* A total score of 3–5 is classified as ''moderate'' croup. It presents with easily heard stridor, but with few other signs.][
* A total score of 6–11 is ''severe'' croup. It also presents with obvious stridor, but also features marked ]chest wall
The thoracic wall or chest wall is the boundary of the thoracic cavity.
Structure
The bone, bony human skeleton, skeletal part of the thoracic wall is the rib cage, and the rest is made up of muscle, skin, and fasciae.
The chest wall has 10 lay ...
indrawing.[
* A total score of ≥ 12 indicates impending ]respiratory failure
Respiratory failure results from inadequate gas exchange by the respiratory system, meaning that the arterial oxygen, carbon dioxide, or both cannot be kept at normal levels. A drop in the oxygen carried in the blood is known as hypoxemia; a rise ...
. The barking cough and stridor may no longer be prominent at this stage.[
85% of children presenting to the emergency department have mild disease; severe croup is rare (<1%).][
]
Prevention
Croup is contagious during the first few days of the infection. Basic hygiene including hand washing can prevent transmission. There are no vaccines that have been developed to prevent croup, however, many cases of croup have been prevented by immunization
Immunization, or immunisation, is the process by which an individual's immune system becomes fortified against an infectious agent (known as the immunogen).
When this system is exposed to molecules that are foreign to the body, called ''non-sel ...
for influenza
Influenza, commonly known as "the flu", is an infectious disease caused by influenza viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These symptoms ...
and diphtheria
Diphtheria is an infection caused by the bacterium '' Corynebacterium diphtheriae''. Most infections are asymptomatic or have a mild clinical course, but in some outbreaks more than 10% of those diagnosed with the disease may die. Signs and s ...
.[ At one time, croup referred to a diphtherial disease, but with vaccination, diphtheria is now rare in the developed world.][
]
Treatment
Most children with croup have mild symptoms and supportive care at home is effective. For children with moderate to severe croup, treatment with corticosteroids and nebulized epinephrine may be suggested. Steroids are given routinely, with epinephrine
Adrenaline, also known as epinephrine, is a hormone and medication which is involved in regulating visceral functions (e.g., respiration). It appears as a white microcrystalline granule. Adrenaline is normally produced by the adrenal glands and ...
used in severe cases.[ Children with ]oxygen saturation
Oxygen saturation (symbol SO2) is a relative measure of the concentration of oxygen that is dissolved or carried in a given medium as a proportion of the maximal concentration that can be dissolved in that medium at the given temperature. It ca ...
less than 92% should receive oxygen,[ and those with severe croup may be hospitalized for observation.][ In very rare severe cases of croup that result in respiratory failure, emergency intubation and ventilation may be required.] With treatment, less than 0.2% of children require endotracheal intubation
Tracheal intubation, usually simply referred to as intubation, is the placement of a flexible plastic tube into the trachea (windpipe) to maintain an open airway or to serve as a conduit through which to administer certain drugs. It is frequently ...
. Since croup is usually a viral disease, antibiotics
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention o ...
are not used unless secondary bacterial infection is suspected. The use of cough medicine
Cold medicines are a group of medications taken individually or in combination as a treatment for the symptoms of the common cold and similar conditions of the upper respiratory tract. The term encompasses a broad array of drugs, including a ...
s, which usually contain dextromethorphan
Dextromethorphan (DXM) is a medication most often used as a cough suppressant in over-the-counter cold and cough medicines. It is sold in syrup, tablet, spray, and lozenge forms. In 2022, the FDA approved a formulation of it combined with bu ...
or guaifenesin
Guaifenesin, also known as glyceryl guaiacolate, is an expectorant medication that aids in the elimination of sputum from the respiratory tract. Chemically it is an ether of guaiacol and glycerine. It is often used in combination with other me ...
, are also discouraged.
Supportive care
Supportive care for children with croup includes resting and keeping the child hydrated. Infections that are mild are suggested to be treated at home. Croup is contagious so washing hands is important. Children with croup should generally be kept as calm as possible. Over the counter medications for pain and fever may be helpful to keep the child comfortable. There is some evidence that cool or warm mist may be helpful, however, the effectiveness of this approach is not clear. If the child is showing signs is distress while breathing (inspiratory stridor
Stridor (Latin for "creaking or grating noise") is a high-pitched extra-thoracic breath sound resulting from turbulent air flow in the larynx or lower in the bronchial tree. It is different from a stertor which is a noise originating in the phar ...
, working hard to breath, blue (or blue-ish) coloured lips, or decrease in the level of alertness
Alertness is the state of active attention by high sensory awareness such as being watchful and prompt to meet danger or emergency, or being quick to perceive and act. It is related for psychology . A lack of alertness is a symptom of a ...
), immediate medical evaluation by a doctor is required.
Steroids
Corticosteroids
Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involve ...
, such as dexamethasone
Dexamethasone is a glucocorticoid medication used to treat rheumatic problems, a number of skin diseases, severe allergies, asthma, chronic obstructive lung disease, croup, brain swelling, eye pain following eye surgery, superior vena cav ...
and budesonide
Budesonide, sold under the brand name Pulmicort among others, is a medication of the corticosteroid type. It is available as an inhaler, nebulization solution, pill, nasal spray, and rectal forms. The inhaled form is used in the long-term mana ...
, have been shown to improve outcomes in children with all severities of croup, however, the benefits may be delayed. Significant relief may be obtained as early as two hours after administration.[ While effective when given ]by injection
By or BY may refer to:
Places
* By, Doubs, France, a commune
* By, Norway, a village
Codes
* Belarus ISO country code
** .by, country-code top-level domain for Belarus
* Burundi FIPS Pub 10-4 and obsolete NATO digram country code
* TUI Airwa ...
, or by inhalation, giving the medication by mouth is preferred.[ A single dose is usually all that is required, and is generally considered to be quite safe.][ Dexamethasone at doses of 0.15, 0.3 and 0.6 mg/kg appear to be all equally effective.
]
Epinephrine
Moderate to severe croup (for example, in the case of severe stridor) may be improved temporarily with nebulized epinephrine
Adrenaline, also known as epinephrine, is a hormone and medication which is involved in regulating visceral functions (e.g., respiration). It appears as a white microcrystalline granule. Adrenaline is normally produced by the adrenal glands and ...
.[ While epinephrine typically produces a reduction in croup severity within 10–30 minutes, the benefits are short-lived and last for only about 2 hours.][ If the condition remains improved for 2–4 hours after treatment and no other complications arise, the child is typically discharged from the hospital.][ Epinephrine treatment is associated with potential adverse effects (usually related to the dose of epinephrine) including ]tachycardia
Tachycardia, also called tachyarrhythmia, is a heart rate that exceeds the normal resting rate. In general, a resting heart rate over 100 beats per minute is accepted as tachycardia in adults. Heart rates above the resting rate may be normal (su ...
, arrhythmia
Arrhythmias, also known as cardiac arrhythmias, heart arrhythmias, or dysrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. A resting heart rate that is too fast – above 100 beats per minute in adults ...
s, and hypertension
Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high bl ...
.
Oxygen
More severe cases of croup may require treatment with oxygen. If oxygen is needed, "blow-by" administration (holding an oxygen source near the child's face) is recommended, as it causes less agitation than use of a mask
A mask is an object normally worn on the face, typically for protection, disguise, performance, or entertainment and often they have been employed for rituals and rights. Masks have been used since antiquity for both ceremonial and practic ...
.
Other
While other treatments for croup have been studied, none has sufficient evidence to support its use. There is tentative evidence that breathing heliox
Heliox is a breathing gas mixture of helium (He) and oxygen (O2). It is used as a medical treatment for patients with difficulty breathing because mixture generates less resistance than atmospheric air when passing through the airways of the lung ...
(a mixture of helium
Helium (from el, ἥλιος, helios, lit=sun) is a chemical element with the symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table. ...
and oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...
) to decrease the work of breathing is useful in those with severe disease, however, there is uncertainty in the effectiveness and the potential adverse effects and/or side effects are not well known. In cases of possible secondary bacterial infection, the antibiotics vancomycin
Vancomycin is a glycopeptide antibiotic medication used to treat a number of bacterial infections. It is recommended intravenously as a treatment for complicated skin infections, bloodstream infections, endocarditis, bone and joint infections, ...
and cefotaxime
Cefotaxime is an antibiotic used to treat a number of bacterial infections in human, other animals and plant tissue culture. Specifically in humans it is used to treat joint infections, pelvic inflammatory disease, meningitis, pneumonia, urin ...
are recommended.[ In severe cases associated with influenza A or B infections, the ]antiviral
Antiviral drugs are a class of medication used for treating viral infections. Most antivirals target specific viruses, while a broad-spectrum antiviral is effective against a wide range of viruses. Unlike most antibiotics, antiviral drugs do no ...
neuraminidase inhibitors Neuraminidase inhibitors (NAIs) are a class of drugs which block the neuraminidase enzyme. They are a commonly used antiviral drug type against influenza. Viral neuraminidases are essential for influenza reproduction, facilitating viral budding from ...
may be administered.[
]
Prognosis
Viral croup is usually a self-limiting disease,[ with half of cases resolving in a day and 80% of cases in two days.][ It can very rarely result in death from ]respiratory failure
Respiratory failure results from inadequate gas exchange by the respiratory system, meaning that the arterial oxygen, carbon dioxide, or both cannot be kept at normal levels. A drop in the oxygen carried in the blood is known as hypoxemia; a rise ...
and/or cardiac arrest
Cardiac arrest is when the heart suddenly and unexpectedly stops beating. It is a medical emergency that, without immediate medical intervention, will result in sudden cardiac death within minutes. Cardiopulmonary resuscitation (CPR) and possib ...
.[ Symptoms usually improve within two days, but may last for up to seven days.][ Other uncommon complications include ]bacterial tracheitis
Tracheitis is an inflammation of the trachea.
Although the trachea is usually considered part of the lower respiratory tract, in ICD-10 tracheitis is classified under "acute upper respiratory infections".
Symptoms
* Increasing deep or barking cro ...
, pneumonia
Pneumonia is an inflammatory condition of the lung primarily affecting the small air sacs known as alveoli. Symptoms typically include some combination of productive or dry cough, chest pain, fever, and difficulty breathing. The severity ...
, and pulmonary edema
Pulmonary edema, also known as pulmonary congestion, is excessive edema, liquid accumulation in the parenchyma, tissue and pulmonary alveolus, air spaces (usually alveoli) of the lungs. It leads to impaired gas exchange and may cause hypoxemia an ...
.[
]
Epidemiology
Croup affects about 15% of children, and usually presents between the ages of 6 months and 5–6 years.[ It accounts for about 5% of hospital admissions in this population.][ In rare cases, it may occur in children as young as 3 months and as old as 15 years.][ Males are affected 50% more frequently than are females, and there is an increased ]prevalence
In epidemiology, prevalence is the proportion of a particular population found to be affected by a medical condition (typically a disease or a risk factor such as smoking or seatbelt use) at a specific time. It is derived by comparing the number o ...
in autumn.[
]
History
The word ''croup'' comes from the Early Modern English
Early Modern English or Early New English (sometimes abbreviated EModE, EMnE, or ENE) is the stage of the English language from the beginning of the Tudor period to the English Interregnum and Restoration, or from the transition from Middle E ...
verb ''croup'', meaning "to cry hoarsely." The noun describing the disease originated in southeastern Scotland and became widespread after Edinburgh
Edinburgh ( ; gd, Dùn Èideann ) is the capital city of Scotland and one of its 32 Council areas of Scotland, council areas. Historically part of the county of Midlothian (interchangeably Edinburghshire before 1921), it is located in Lothian ...
physician Francis Home published the 1765 treatise ''An Inquiry into the Nature, Cause, and Cure of the Croup''.
Diphtheritic croup
Diphtheria is an infection caused by the bacteria, bacterium ''Corynebacterium diphtheriae''. Most infections are asymptomatic or have a mild Course (medicine), clinical course, but in some outbreaks more than 10% of those diagnosed with the di ...
has been known since the time of Homer
Homer (; grc, Ὅμηρος , ''Hómēros'') (born ) was a Greek poet who is credited as the author of the ''Iliad'' and the ''Odyssey'', two epic poems that are foundational works of ancient Greek literature. Homer is considered one of the ...
's ancient Greece
Ancient Greece ( el, Ἑλλάς, Hellás) was a northeastern Mediterranean civilization, existing from the Greek Dark Ages of the 12th–9th centuries BC to the end of classical antiquity ( AD 600), that comprised a loose collection of cult ...
, and it was not until 1826 that viral croup was differentiated from croup due to diphtheria
Diphtheria is an infection caused by the bacterium '' Corynebacterium diphtheriae''. Most infections are asymptomatic or have a mild clinical course, but in some outbreaks more than 10% of those diagnosed with the disease may die. Signs and s ...
by Bretonneau. Viral croup was then called "faux-croup" by the French and often called "false croup" in English, as "croup" or "true croup" then most often referred to the disease caused by the diphtheria bacterium. False croup has also been known as pseudo croup or spasmodic croup. Croup due to diphtheria has become nearly unknown in affluent countries in modern times due to the advent of effective immunization
Immunization, or immunisation, is the process by which an individual's immune system becomes fortified against an infectious agent (known as the immunogen).
When this system is exposed to molecules that are foreign to the body, called ''non-sel ...
.
One famous fatality of croup was Napoleon
Napoleon Bonaparte ; it, Napoleone Bonaparte, ; co, Napulione Buonaparte. (born Napoleone Buonaparte; 15 August 1769 – 5 May 1821), later known by his regnal name Napoleon I, was a French military commander and political leader who ...
's designated heir, Napoléon Charles Bonaparte. His death in 1807 left Napoleon without an heir and contributed to his decision to divorce from his wife, the Empress Josephine de Beauharnais
Josephine may refer to:
People
* Josephine (given name), a given name (including a list of people with the name)
* Josephine (singer), a Greek pop singer
Places
*Josephine, Texas, United States
*Mount Josephine (disambiguation)
* Josephine Coun ...
.
References
External links
*
{{Respiratory pathology
Animal viral diseases
Acute upper respiratory infections
Pediatrics
Wikipedia emergency medicine articles ready to translate
Wikipedia medicine articles ready to translate (full)
Cough
de:Pseudokrupp