In the preliminary stages, symptoms of bronchiolitis are similar to those of common cold. As the disease progresses to more advanced stages, signs and symptoms take a severe turn, and include:

• Development of cyanosis, characterized by bluish coloration of skin, which occurs due to lack of oxygen supply
• Cough that eventually gets worse
• Wheezing accompanied by dyspnea
• Fatigue
• Fever
• Tachypnea
• Development of intercostal retractions, a condition, wherein the muscles surrounding the ribs sinks in, when the affected child tries to breathe
• The nostrils of the affected child widen when he tries to inhale [8]

• Fever

  Our findings support the limited role of radiography in the evaluation of hospitalized infants with bronchiolitis, especially patients without fever or hypoxia. KEYWORDS: bronchiolitis; fever; hypoxia; imaging; infant; radiography [ncbi.nlm.nih.gov]

  […] infant experiences an unexpected fever after several days of hospitalization; they more generally address the issue of fever at the time of presentation for acute care. [doi.org]

  Keep your baby away from anyone who has a cold, fever, or runny nose. Avoid sharing eating utensils and drinking cups with anyone who has a cold, fever, or runny nose. [healthychildren.org]

  One study found no difference in duration of fever and one study found no difference in presence of fever on day two. [cochrane.org]

• Fatigue

  A child with severe bronchiolitis may get fatigued from the work of breathing and have poor air movement in and out of the lungs due to the clogging of the small airways. [rchsd.org]

  […] more advanced stages, signs and symptoms take a severe turn, and include: Development of cyanosis, characterized by bluish coloration of skin, which occurs due to lack of oxygen supply Cough that eventually gets worse Wheezing accompanied by dyspnea Fatigue [symptoma.com]

  Indications for hospitalization include accelerating respiratory distress, ill appearance (eg, cyanosis, lethargy, fatigue), apnea by history, hypoxemia, and inadequate oral intake. [merckmanuals.com]

• Cough

  Your child may have: Worsening cough More frequent coughing Wheezing Fast breathing Indrawing (The skin being sucked in at the neck, collarbones or between the ribs with each breath) Vomiting after coughing Decreased appetite Difficulty breast or bottle [albertahealthservices.ca]

  In many cases, bronchiolitis mimics the signs of common cold and cough in the preliminary stages. As the disease advances, affected individuals would also experience wheezing, coughing and difficulty in breathing. [symptoma.com]

  An irritating cough can linger a bit longer. In some cases the irritating cough may grumble on for several weeks after the other symptoms have gone. [patient.info]

  The symptoms of bronchiolitis usually follow this timeline: Days 1-3: coughing and nasal congestion with low-grade fevers Days 4-7: wheezing, difficulty breathing and sometimes poor feeding or vomiting from thick nasal congestion and persistent coughing [childrensalblog.org]

  Duration Cases of bronchiolitis usually last about 12 days, but kids with severe cases can cough for weeks. [rchsd.org]

• Tachypnea

  Two months ago, the patient was seen for tachypnea and wheezing, and diagnosed with severe respiratory syncytial virus (RSV) bronchiolitis. [medbullets.com]

  The primary outcome was escalation of care due to treatment failure (defined as meeting ≥3 of 4 clinical criteria: persistent tachycardia, tachypnea, hypoxemia, and medical review triggered by a hospital early-warning tool). [ncbi.nlm.nih.gov]

  The course begins with a two-to-three-day viral prodrome of fever, cough and rhinorrhea progressing to tachypnea, wheeze, crackles and a variable degree of respiratory distress. [doi.org]

  Tachypnea (i.e., respiratory rate >70 breaths per minute) may be associated with risk for severe disease and may warrant additional evaluation for pneumonia or other lower respiratory tract infection. 6 Radiologic and laboratory testing It is not necessary [clinicaladvisor.com]

  Symptoms and Signs Typically, an affected infant has URI symptoms with progressively increasing respiratory distress characterized by tachypnea, retractions, and a wheezy or hacking cough. [merckmanuals.com]

• Rales

  On days 3 to 5, the following symptoms develop: tachypnea, wheezing, rales, and signs of respiratory distress (eg, grunting, nasal flaring, inter-/subcostal retractions). [mdedge.com]

  Presentation History of URI symptoms Cough Decreased feeding Respiratory distress (presents day 3-5 of illness) Physical exam findings Low grade temperature Tachypnea and respiratory distress Wheezing Rales Dehydration Hypoxia Diagnosis Clinical diagnosis [pedclerk.bsd.uchicago.edu]

  Moist and/or wheezing rales were frequent, and pulmonary interstitial infiltration was seen in 66.4% of chest X-rays. [nature.com]

  Individuals with BOOP may develop small crackling or rattling sounds in the lung (crackles or rales) that are apparent upon physical examination. [rarediseases.org]

  Combining these definitions, the most typical findings include: a child less than 2 years old presenting with onset of wheezing and signs of a concomitant upper respiratory tract infection such as rhinorrhea and cough; coarse rales on examination, typically [clinicaladvisor.com]

• Dyspnea

  This paper examines a 58-year-old man with SS, severe dyspnea and recurrent exacerbations associated with bronchiolitis-bronchiectasis. [ncbi.nlm.nih.gov]

  […] progresses to more advanced stages, signs and symptoms take a severe turn, and include: Development of cyanosis, characterized by bluish coloration of skin, which occurs due to lack of oxygen supply Cough that eventually gets worse Wheezing accompanied by dyspnea [symptoma.com]

• Dry Cough

  There will be: Very low FEV1 ( Dry cough SOB Wheeze There is very little treatment. Some cases may improve with a lung transplant. There are many causes, not just RSV infection in childhood, often including occupational lung disease. [almostadoctor.co.uk]

  When inhaled, diacetyl can cause a persistent dry cough, shortness of breath, wheezing, phlegm production, fatigue, drowsiness, headache, fever, aches and nausea. [nationaljewish.org]

  He might also have a more troublesome, dry cough and may also be reluctant to feed, probably because he's having trouble breathing through his nose. His heart might seem to be racing and he might be taking fast, shallow breaths. [bounty.com]

  Symptoms Symptoms can be mild in most cases peaking in severity 2 -3 days after starting and present with a simple cold, runny nose, cough and mild fever As the infection travels down to the smaller airways symptoms can be more severe - Episodes of dry [health.ccm.net]

  Mild cough. As the infection progresses, symptoms become more severe but usually start to improve after 3 days. Advanced symptoms include: A dry cough. Rapid breathing. Pauses between breaths. Problems with feeding. Vomiting after feeding. [medic8.com]

• Vomiting

  Call your doctor if your child: is breathing quickly, especially if he or she also has retractions or wheezing might be dehydrated due to vomiting or a poor appetite is sleepier than usual has a high fever Get medical care right away if: Your child has [m.kidshealth.org]

  When to Call the Doctor Call your doctor if your child: is breathing quickly, especially if this is accompanied by retractions or wheezing might be dehydrated due to vomiting or a poor appetite is sleepier than usual has a high fever has a worsening cough [rchsd.org]

  The infant may be irritable, feeding poorly and vomiting. Other causative viruses for bronchiolitis are human meta-pneumovirus, rhinovirus, adenovirus and influenza virus. [erswhitebook.org]

• Loss of Appetite

  Runny nose Slight fever (under 101° F) Cough Wheezing Rapid breathing Shallow breathing Loss of appetite Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. [my.clevelandclinic.org]

  Below are the most common symptoms of bronchiolitis: Runny nose Congestion Fever Cough Fast or hard breathing Wheezing Loss of appetite Irritability Vomiting These symptoms often last about a week. They may look like other health problems. [urmc.rochester.edu]

• Nausea

  It can also cause nausea, vomiting, headache, drowsiness, delirium and hallucinations in high concentrations. [nationaljewish.org]

  Your child is not eating, has nausea, or is vomiting. Your child is very tired or weak, or he or she is sleeping more than usual. You have questions or concerns about your child's condition or care. [drugs.com]

  Adverse events (tachycardia, hypertension, pallor, tremor, nausea, vomiting, diarrhea and acute urinary retention) No significant adverse events related to hypertonic saline inhalation were observed in 11 trials. [dx.doi.org]

  Adverse events (tachycardia, hypertension, pallor, tremor, nausea, vomiting, diarrhoea, and acute urinary retention). [doi.org]

• Cyanosis

  Cyanosis is caused by lack of oxygen. Pauses in breathing (apnea). Apnea is most likely to occur in premature infants and in infants within the first two months of life. Dehydration. Low oxygen levels and respiratory failure. [mayoclinic.org]

  As the disease progresses to more advanced stages, signs and symptoms take a severe turn, and include: Development of cyanosis, characterized by bluish coloration of skin, which occurs due to lack of oxygen supply Cough that eventually gets worse Wheezing [symptoma.com]

  Signs of distress may include circumoral cyanosis, deepening retractions, and audible wheezing. Fever is usually but not always present. [merckmanuals.com]

• Irritability

  Causes The disease can be caused by breathing in irritant fumes, such as chlorine, ammonia, oxides of nitrogen or sulfur dioxide. [nationaljewish.org]

  Oxygen No oxygen requirement May require oxygen Requires oxygen Indrawing No/ mild indrawing Intercostal and/or tracheosternal Severe with nasal flaring Behaviour Normal Some/ intermittent irritability Irritability and/or lethargy The Melbourne Royal [ausmed.com]

  When caused by an irritating substance, people may experience irritation in other parts of the body, including the eyes, nose, and throat. [foundation.chestnet.org]

  It affects the small airways called the bronchioles (hence the name bronchiolitis) and can cause them to be irritated and swollen. When this happens, it can lead to wheezing and trouble breathing. [health.harvard.edu]

• Grunting

  On physical exam, he has increased work of breath with nasal flaring, grunting, and intercostal retractions. He also has bilateral wheezes. [step2.medbullets.com]

  Signs of respiratory distress may include grunting, nasal flaring, indrawing, retractions or abdominal breathing. There may or may not be a history of exposure to an individual with a viral URTI. [doi.org]

  More severe cases may be associated with nasal flaring, grunting, or the skin between the ribs pulling in with breathing. [en.wikipedia.org]

  Significant multivariable predictors and their odds ratios (ORs) were as follows: age (0.9), oxygen saturation (1.3), apnea (3.4), dehydration (3.2), nasal flaring and/or grunting (2.4), poor feeding (2.1), chest retractions (1.9), and respiratory rate [ncbi.nlm.nih.gov]

A preliminary physical examination will be conducted, to study the signs and symptoms of the disease, and to also listen to the wheezing sounds, with the help of a stethoscope. No other tests would be required, other than physical examination. However, in case the child has developed severe bronchiolitis, then the following tests would be employed to check for sings of pneumonia [9].

• Chest x-ray: This would be done, to check for signs of pneumonia.
• Blood tests: Are necessary to determine the levels of leukocytes. Leukocytosis is a sign of infection. Blood tests would also help analyze the levels of oxygen in the body.
• Mucus sample test: A swab of the mucus sample will be tested, for the presence of virus [10].

• Reversible Airway Obstruction

  Although it is true that a small subset of children with bronchiolitis may have reversible airway obstruction resulting from smooth muscle constriction, attempts to define a subgroup of responders have not been successful to date. [doi.org]

Bronchiolitis can be successfully treated at home, with supportive care. The following methods are adopted, for treating children affected with lung infections [11]:

• Drinking plenty of fluids is necessary. Mothers are advised to continue with breast milk, and, or formula milk, for infants.
• Plenty of rest is advised.
• Use of humidifier is indicated, which would help in loosening the thickened accumulated mucus.
• In many cases, nebulized albuterol treatment is also administered. Inhaled hypertonic saline is also an effective treatment regime [12].

The prognosis of the condition is favorable, if treatment is initiated in the preliminary stages. Failure to do so may cause breathing problems in the child, and require hospital admissions. Symptoms begin to improve within 3 days, and children should completely recover by 1 week. In rare cases, children develop pneumonia, and other associated respiratory infections. However, affected children are at an increased risk of developing wheezing problems in the future, and can even develop asthma later in their lives [6] [7].

Respiratory syncytial virus (RSV) causes bronchiolitis in majority of the cases. It is a contagious disease, and can spread through infected droplets, that are spread in air by individuals contracted with this disease condition. In addition to RSV, other viruses such as influenza virus, adenovirus and parainfluenza virus can also cause bronchiolitis.

The condition is common during the winter season, and early months of spring. Children less than 2 years and those with a compromised immune system fall easy prey to the virus [2].

It has been estimated that in the US, about 25% of respiratory tract infections occur in the first year of life. It has also been reported that about 132,000 to 172,000 RSV-related hospitalizations occur in the pediatric population. The estimated cost from hospitalization is calculated to be approximately more than $700 million annually [3].

Anatomically, bronchioles are the small airways, measuring less than 2mm in diameter. These airways get inflamed due to viral agents, which in turn causes mucus buildup, making passage of air difficult. Such sequence of events causes difficulty in passage of air, into and out of the lungs, making breathing difficult for the affected individuals [4]. Bronchiolitis is a contagious disease. It is spread when healthy individuals come in contact with respiratory droplets of infected individuals, when they sneeze, cough or talk [5].

Majority of the cases of bronchiolitis can seldom be prevented; owing to the fact, that the virus is commonly found in the environment. However, individuals are still advised to adopt certain measures, such as frequent hand washing, which can, to a certain extent, prevent the spread of the disease.

Boosting a child’s immunity is yet another way, which can help prevent development of bronchiolitis. A drug known as palivizumab, has promising effects in boosting the immune system.

Such a type of lung infection is a common occurrence amongst children less than 2 years of age. In many cases, bronchiolitis mimics the signs of common cold and cough in the preliminary stages. As the disease advances, affected individuals would also experience wheezing, coughing and difficulty in breathing. Supportive care forms the basis of the treatment regime, and children do well with medications and nebulized epinephrine [1].

• Definition: Bornchiolitis is inflammation of the bronchioles of the lungs, due to viral infections. This causes accumulation of mucus in the bronchioles, which ultimately leads to breathing difficulties in the affected children. The condition is common during the winter season, and children less than 2 years of age, commonly fall prey to it.
• Cause: The respiratory syncytial virus is the major cause of bronchiolitis. Other viruses such as influenza virus, parainfluenza virus and adenovirus can also cause this disease condition. Bronchiolitis is an infectious disease, and can spread by coming in contact with respiratory droplets of infected individuals.
• Symptoms: Symptoms of bronchiolitis include cough, wheezing, cyanosis, fatigue, fever and rapid breathing. Affected children experience intercostals contractions, which is characterized by contractions of the ribs muscles, when the child breathes.
• Diagnosis: In majority of the cases, preliminary physical examination is enough, to diagnose the condition. However, if the child is suffering from severe form of bronchiolitis, then more tests would be required, to diagnose onset of pneumonia.
• Treatment: Many children can be treated at home, through supportive care. Medications are of little help in treating viral infections. In addition, use of bronchodilators in such cases, is also contraindicated. Affected children are advised plenty of rest, along with fluids, and mothers are asked to continue breast feeding their babies. Use of nebulized albuterol is also indicated.

1. Scottish Intercollegiate Guidelines Network. Bronchiolitis in children. A national clinical guideline. 2006. http://www.sign.ac.uk/pdf/sign91.pdf.
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3. Holman RC, Curns AT, Cheek JE, et al. Respiratory syncytial virus hospitalizations among American Indian and Alaska Native infants and the general United States infant population. Pediatrics 2004; 114:e437.
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