URI Lower - Diebel Handout - Bronchiolitis

Question 1

What does Bronchiolitis cause?

Answer 1

Inflammation of the bronchial tress as low as the bronchioles but does not involve the alveoli.

Question 2

What population does bronchiolitis usually occur in? And why?

Answer 2

Infants younger than 1 year of age.

They have narrower airways.

Question 3

What is the most common cause of bronchiolitis?

Answer 3

RSV

Question 4

What are early symptoms of bronchiolitis?

Answer 4

Similar to symptoms of viral upper respiratory tract infection and include mild rhinorrhea, cough, and sometimes a low-grade fever. In some infants and young kids this infection extends down into the LRT.

Question 5

What are some common symptoms of bronchiolitis?

Answer 5

• Tachypnea
• Tachycardia
• Fever (101.3-102.2F)
• Diffuse expiratory wheezing
• Inspiratory crackles
• Nasal flaring
• Vomiting
• Cyanosis
• Hyperinflation of the lungs

Question 6

When is bronchiolitis most common?

Answer 6

Fall and winter months

Question 7

What is the pathogenesis of bronchiolitis?

Answer 7

1. Infection of the bronchiolar respiratory and ciliated epithelial cells
2. Increased mucous secretion and cell death
3. Peribronchiolar lymphocytic infiltrate and submucosal edema
4. Debris and edema in walls of bronchioles
5. Narrowing and obstruction of airways
6. Macrophages clear debris in airways
7. Pulmonary epithelial cells regenerate 3-4 days after infection clears

Question 8

Clinical disease bronchiolitis develops ONLY in. . .

Answer 8

. . infants and young children.

Question 9

What percentage of cases of bronchiolitis occur in children under 1 year of age?

Answer 9

75% of cases

Question 10

What percentage of cases of bronchiolitis occur in children under 2 years of age?

Answer 10

95%

Question 11

What is the peak incidence age for bronchiolitis?

Answer 11

2-8 months of age

Question 12

What usually ends a bronchiolitis infection?

Answer 12

It is usually self-limiting.

Question 13

What percentage of 2 year old children have serologic evidence of past RSV infection?

Answer 13

95%

Question 14

What are risk factors for bronchiolitis?

Answer 14

• Age younger than 6 years
• Bottle feeding
• Prematurity (born before 37 wks)
• Exposure to cigarette smoke
• Crowded living conditions

Question 15

How is the RSV virus transmitted?

Answer 15

Person to person via direct contact with nasal secretions or airborne droplets.

Question 16

What does a diagnosis of bronchiolitis involve?

Answer 16

Observation of the patient’s (1) signs and symptoms, (2) chest radiographs (to rule out pneumonia), and (3) antigen testing for RSV in nasal washings.

Question 17

When should nasal washing be obtained and tested for RSV?

Answer 17

Children who are hospitalized and children at risk for severe disease.

Question 18

What treatment might patients with bronchiolitis require?

Answer 18

• Supplemental oxygen

- Replacement of electrolytes and fluids

Question 19

What can be given to high risk patients to prevent bronchiolitis?

Answer 19

RespiGam (immunoglubulin reactive with respiratory syncytial virus) or palivizumab (humanized monoclonal antibody reactive with respiratory syncytial virus)

Question 20

What are high risk patients (for bronchiolitis)?

Answer 20

• Infants born prematurely
• Patients with cystic fibrosis
• Patients who have hemodynamically significant cyanotic or cyanotic congenital heart disease
• Patients who are immunodeficient