Recommended
More Related Content
What's hot
What's hot (20)
Similar to Pneumonia pedia
Similar to Pneumonia pedia (20)
Recently uploaded
Recently uploaded (20)
Pneumonia pedia
- 1. Pneumonia
- 2. Pneumonia • acute infection of the pulmonary parenchyma • inflammation of the lung parenchyma • is the leading cause of death globally - children <5 yr. (From World Health Organization and Maternal and Child Epidemiology Estimation Group estimates, 2015.)
- 3. Causes • mostly caused by microorganisms • Bacterial and Viral Infectious • Aspiration of food, gastric acid, foreign bodies, hydrocarbons & lipoid substances • Hypersensitivity reaction • Drug or radiation-induced pneumonitis Non infectious
- 4. Infectious • Bacterial - Streptococcus pneumoniae (pneumococcus) - children 3 weeks to 4 yr of age. - Mycoplasma pneumoniae and Chlamydophila pneumoniae - children age 5 yr and older. • Viral pathogens are the most common causes of LRTI in infants and children older than 1 month but younger than 5 yr of age.
- 5. Pneumonia Etiologies Grouped by Age of the Patient AGE GROUP FREQUENT PATHOGENS (IN ORDER OF FREQUENCY) Neonates (<3 wk) Group B streptococcus, Escherichia coli, other Gram-negative bacilli, Streptococcus pneumoniae, Haemophilus influenzae (type b,* nontypeable) 3 wk - 3 mo Respiratory syncytial virus, other respiratory viruses (rhinoviruses, parainfluenza viruses, influenza viruses, human metapneumovirus, adenovirus), S. pneumoniae, H. influenzae (type b,* nontypeable); Chlamydia trachomatis Adapted from Kliegman RM, Marcdante KJ, Jenson HJ, et al: Nelson essentials of pediatrics , ed 5, Philadelphia, 2006, Elsevier, p. 507.
- 6. Pneumonia Etiologies Grouped by Age of the Patient 4 mo - 4 yr Respiratory syncytial virus, other respiratory viruses (rhinoviruses, parainfluenza viruses, influenza viruses, human metapneumovirus, adenovirus), S. pneumoniae, H. influenzae (type b,* nontypeable), Mycoplasma pneumoniae, group A streptococcus ≥5 yr M. pneumoniae, S. pneumoniae, Chlamydophila pneumoniae, H. influenzae (type b,* nontypeable), influenza viruses, adenovirus, other respiratory viruses, Legionella pneumophila Adapted from Kliegman RM, Marcdante KJ, Jenson HJ, et al: Nelson essentials of pediatrics , ed 5, Philadelphia, 2006, Elsevier, p. 507.
- 7. Defense Mechanism of Lower Respiratory Tract Process against Infection Mucociliary Clearance Macrophages Secretory Immunoglobulin A Clearing of the Airways by Coughing
- 8. Pathogenesis Bacteria enter the lungs (from nose, airborne droplets or blood) Bacteria may invade spaces between cells and alveoli Macrophages and neutrophils inactivate the bacteria. Neutrophils also release cytokines When macrophages are overwhelmed General activation of immune system. Inflammatory Response (Increases local microvascular permeability)
- 9. Inflammatory Response (Increase Microvascular Permeability) Movement of fluid , WBC, Proteins in alveolar space Production of a fibrin rich exudates that fills infected and neighboring alveoli spaces alveoli airless Reduced gas exchange –organs oxygen deprived Cytokines ad Chemokines (TNF, IL-1, IL – 6) , spill in the systemic circulation systemic Inflammatory response - Activates production of WBC by bone Marrow - Increases cardiac output - Elevates Body Temperature - Responsible for sickness behavior: Fatigue, anorexia, coldness Tachypnea and Tachycardia IL-1 , TNF - increases cyclooxygenase converts AA to Prostaglandin Resets temperature to a higher level – elevated Temperature
- 10. Clinical Manifestations • Rhinitis • Cough • Fever • Tachypnea • Increased work of breathing • Cyanosis • Lethargy
- 11. Infants • Upper respiratory tract infection • Poor feeding and appear ill • respiratory distress manifested as: - grunting - nasal flaring - retractions (supraclavicular, intercostal, and subcostal areas) - tachypnea - tachycardia - air hunger; and - often cyanosis
- 12. PHYSICAL FINDINGS BASED ON STAGE OF PNEUMONIA Early in course of illness - Diminished breath sounds - Scattered crackles - Ronchi over affected lung field Upon development of increasing consolidation or complications - Dullness on percussion - Diminished breath sounds - Chest lag on affected side - Abdominal pain (common in lower lobe pneumonia) - Abdominal distention (d/t gastric dilation from swallowed air or ileus) - Liver may seem enlarged (d/t downward displacement of diaphragm secondary to hyperinflation of lungs or superimposed CHF)
- 13. VIRAL PNEUMONIA BACTERIAL PNEUMONIA Description Results from spread of infection along airways accompanied by direct injury of respiratory epithelium Organisms colonize the trachea and subsequently gain access to the lungs / direct seeding of lung tissue after bacteremia Fever Low fever (Begins) High Fever Signs and Symptoms Wheezes are more common in viral than bacterial Adults & Older children : - Drowsiness w/ intermittent periods of restlessness, Rapid respirations ,- Anxiety and delirium Peripheral white blood cell (WBC) count Normal or elevated but is usually not higher than 20,000/mm3, Range of 15,000 - 40,000/mm3 Associated Symptoms Gastrointestinal disturbances : vomiting, anorexia, diarrhea, and abdominal distention Definitive Tests Rests on the isolation of a virus or detection of the viral genome or antigen in respiratory tract secretions. Requires isolation of an organism from the blood, pleural fluid, or lung.
- 14. References: • Dantzer, R. (2006). Cytokine, Sickness Behavior, and Depression. Neurologic Clinics, 24(3), 441–460. doi: 10.1016/j.ncl.2006.03.003 • Kumar, V., Abbas, A. K., & Aster, J. C. (2015). Robbins and Cotran pathologic basis of disease. Philadelphia: Elsevier- Saunders. • Elsevier Health Sciences. (2018). Harriet Lane Handbook. Saint Louis.
- 17. Pathogenesis: Viral Pneumonia Spread of infection along airways accompanied by direct injury of respiratory epithelium Airway obstruction d/t: Swelling, abnormal secretions & cellular debris Significant hypoxemia d/t: Atelectasis, interstitial edema, V/Q mismatch
- 18. M. Pneumoniae Colonization of trachea or direct seeding after bacteremia attaches to respiratory epithelium Inhibits ciliary action Cellular destruction Progression of infection Airway obstruction d/t sloughed cellular debris, inflammatory cells, & mucus S. Pneumoniae Infection Produces local edema Aids in proliferation of organisms & spread into adjacent portion of lung Characteristic focal lobar involvement
- 19. Group A Streptococcus LRTI • necrosis of tracheobronchial mucosa • formation of large amounts of exudate, edema, and local hemorrhage, with extension into the interalveolar septa • involvement of lymphatic vessels • Increased likelihood pleural involvement S. Aureus Pneumonia Extensive areas of hemorrhagic necrosis & irregular areas of cavitation of lung parenchyma Pneumatoceles, empyema, bronchopulmonary fistulas
Editor's Notes
- Pneumonia is the leading infectious killer of children worldwide, as shown by this illustration of global distribution of cause-specific infectious mortality among children younger than age 5 yr in 2015. Pneumonia causes one-third of all under-5 deaths from infection. (From World Health Organization and Maternal and Child Epidemiology Estimation Group estimates, 2015.) Pneumonia mortality is closely linked to poverty. More than 99% of pneumonia deaths are in low- and middle-income countries, with the highest pneumonia mortality rate occurring in poorly developed countries in Africa and South Asia
- Most cases of pneumonia are caused by microorganisms. The cause of pneumonia in an individual patient is often difficult to determine because direct culture of lung tissue is invasive and rarely performed. Cultures performed on specimens in children obtained from the upper respiratory tract or sputum typically do not accurately reflect the cause of lower respiratory tract infection. Hypersensitivity pneumonitis (extrinsic allergic pneumonitis) “agricultural dust” is a disease of the lungs in which your lungs become inflamed as an allergic reaction to inhaled dust, fungus, molds or chemicals. Exogenous lipoid pneumonia (ELP) is a rare form of pneumonia caused by inhalation or aspiration of a fatty substance. ELP has been reported with inhalation or ingestion of petroleum jelly, mineral oils, “nasal drops,” and even intravenous injection of olive oil. Drug induced pneumonitis – adverse drug reaction due to antineoplastic agents are a common for of iatrogenic injury and the lungs are frequent target
- It is probable that this decline results from the introduction of antibiotics, vaccines, and the expansion of medical insurance coverage for children. Improved access to healthcare in rural areas of developing countries and the introduction of pneumococcal conjugate vaccines (see Chapter 182) were also important contributors to the further reductions in pneumonia-related deaths. Viral pathogens are the most common causes of lower respiratory tract infections in infants and children older than 1 mo but younger than 5 yr of age. Viruses can be detected in 40-80% of children with pneumonia using molecular diagnostic methods
- The age of the patients can likely suggest the pathogens H. influenzae or S. pneumoniae has been significantly reduced in areas where routine immunization has been implemented.
- Of the respiratory viruses, respiratory syncytial virus (RSV) and rhinoviruses are the most commonly identified pathogens, especially in children younger than 2 yr of age. RSV is particularly severe among infants and young children. Immunization status is relevant because children fully immunized against H. influenzae type b and S. pneumoniae are less likely to be infected with these pathogens. Children who are immunosuppressed or who have an underlying illness may be at risk for specific pathogens, such as Pseudomonas spp. in patients with cystic fibrosis.
- Lungs are essential organs for respiration. Their cardinal function is , the exchange of gases between inspired air and blood. The lower respiratory tract is normally kept sterile by physiologic defense mechanisms, including mucocilliary clearance, the properties of normal secretions such as secretory immunoglobulin (Ig) A, and clearing of the airway by coughing. Immunologic defense mechanisms of the lung that limit invasion by pathogenic organisms include macrophages that are present in alveoli and bronchioles, secretory IgA, and other immunoglobulins. Trauma, anesthesia, and aspiration increase the risk of pulmonary infection. Cilia, tiny muscular, hair-like projections on the cells that line the airway, are one of the respiratory system's defense mechanisms. Cilia propel a liquid layer of mucus that covers the airways. The mucus layer traps pathogens (potentially infectious microorganisms) and other particles, preventing them from reaching the lungs. Pathogens and particles that are trapped on the mucus layer are coughed out or moved to the mouth and swallowed. IgA – (comes from vascular compartment thru diffusion and made up by plasma cells in the lung tissue), most abundant immunoglobulin in the upper respiratory tract, serves as an immunologic barrier, inhibiting binding of microorganism to the mucosal surface and bacterial growth,.
- Most often occurs when respiratory tract organisms colonize the trachea and subsequently gain access to the lungs but pneumonia may also result from direct seeding of lung tissue after bacteremia.
- Pneumonia is frequently preceded by several days of symptoms of an upper respiratory tract infection, typically rhinitis and cough. Fever – low grade in viral than bacterial Tachypnea - most consistent clinical manifestation of pneumonia Increased work of breathing accompanied by intercostal, subcostal, and suprasternal retractions, nasal flaring, and use of accessory muscles is common. Severe infection may be accompanied by cyanosis and lethargy, especially in infants. Auscultation of the chest may reveal crackles and wheezing
- Respiratory distress means results when breathing does not match the body’s metabolic demand for oxygen due to failure of oxygenation and or ventilation. While respiratory failure is a syndrome which the respiratory system fails in one or both of its gas exchange functions: oxygenation and carbon dioxide elimination. According to Bates , In infants, abnormal work of breathing combined with abnormal findings on auscultation is the best finding for ruling in pneumonia.
- Group A streptococcus lower respiratory tract infection typically results in more diffuse lung involvement with interstitial pneumonia.