Pneumonia

1. Pneumonia Lina Chen MD West China Second University Hospital, Sichuan Universtiy

2. Pneumonia • A potentially serious respiratory infection • Diagnosis requires both clinical presentation and diagnostic studies

3. Objectives • Know etiologic agents and pathogenesis of pneumonia • Recognize clinical presentation and know possible complications • Know how to diagnose and treat pediatric patients with pneumonia

4. Introduction • The most frequent diagnosis in pediatric inpatient department :1/3-1/2 • The most important cause of death in children from developing country • Incidence peaks :between 1 and 5 years of age • The most important one of four common pediatric diseases in China : pneumonia, diarrhea, anemia and ricket

5. Introduction • Definition • Pneumonia is an inflammation of the lungs. • Causes • Microorganisms: viral，bacterial and atypical organisms • Non-infectious causes: aspiration of food or gastric acid, foreign bodies, hydrocarbons and lipoid substances, hypersensivity reactions, drug-or-radiation-induced pneumonitis

6. Introduction • Risk factors for the development of pneumonia • Lung disease: asthma, cystic fibrosis, respiratory anormaly • Anatomical problems: tracheoesophageal fistula • Gastroesophageal reflux • Neurologic disorders • Diseases which alter immune system: immunodeficiency, hemoglobinopathies

7. Classification 1. based on pathological features • Parenchymal pneumonia • Brochopneumonia • Lobarpneumonia • Interstitial pneumonia • Mixed type of pneumonia

8. Classification 2. based onetiology

9. Etiology ---pathogen Atypical organisms Bacteria Viruses • In developed countries, virus is the most common cause • in developing countries, bacteria are the most common causes • Streptococci is the most common bacterial cause • aspiration or the hematogenous route

10. Classification 3. based oncourse of disease • Acute Pneumonia • within one month, most in 2-3 weeks • Most common • Prolonged Pneumonia • 1 month to 3 months • Chronic Pneumonia • over 3 months • hard to treat , must search reason

11. Classification 4. based onclinical manifestations • Mild pneumonia: Mainly involves respiratory system, no generalized toxic symptoms • Severe pneumonia:Besides respiratory system, other systems might be severely involved • Respiratory failure • Circulatory system: congestive heart failure • Digestive system: abdominal distention , toxic intestinal paralysis • CNS: toxic encephalopathy • Other: body fluid derangement ,disseminated intravascular coagulation (DIC)

12. Classification 5. based ononset time • Community acquired pneumonia, CAP • Hospital Acquired Pneumonia, HAP

13. Pathophysiology • Edema and accumulation of mucus→bronchiolar obstruction • Walls of alveoli →thicken • Alveoli are filled with inflammatory exudates→impairs the normal exchange of gases in the lungs • Diminished ventilation of the alveoli →hypoxemia and carbon dioxide retention →interfere normal metabolic process and normal function of the chief organs

14. Pathophysiology

15. Clinical manifestations • Prodromal symptoms • Upper respiratory tract infection: rhinitis, cough • General condition • diminished appetite, restless, • gastrointestinal disturbance: vomiting, anorexia, diarrhea,

16. Clinical manifestations • Fever • Temperatures are generally lower in viral pneumonia than in bacterial pneumonia. • Infants may have hypothemia. • Cough • dry cough →wet cough • Neonates and infants may present with choking cough, groan.

17. Clinical manifestations • Tachypnea • The most consistent clinical manifestation of pneumonia • Increased respiratory rate: ＞60 breaths/min in neonate, ＞50 in infants 11 months of age or less, ＞40 in children over 11 months • Increased work of breathing accompanied by supraclavicular, intercostal, and subcostal retractions, nasal flaring, and use of accessory muscles • Cyanosis • Cyanosis will appear when SaO2 ＜85% and unoxygenated Hb＞5g/dl • location: face, finger nails.

18. Clinical manifestation • Physical findings depend on the stage of pneumonia • Early course: • diminished breath sounds, scattered crackles, rhonchi, wheezing • difficult to localize the source of these adventitious sounds in very young children • Development of increasing consolidation or complications: • cyanosis: • dullness on percussion • abdominal distention: gastric dilation from swallowed air • liver enlargement: downward displacement of the diaphragm

19. Severe pneumonia • Circulatory system: congestive heart failure • Central nervous system: toxic encephalopathy • Digestive system: toxic intestinal paralysis • Disseminated intravascular coagulation (DIC)

20. Severe pneumonia ---Circulatory system • Myocarditis: pallor, tachypnea, and arrhythmia, low and dull heart sound • Heart failure • tachypnea, breath rate more than 60/min • tachycardia, heart rate is quicker than 160 -180 beats/min • suddenly extreme restless, obvious cyanosis, pallor or grey complexion • heart sound decrease, gallop rhythm, high distention of jugular vein occurs • liver enlarged rapidly, liver can be palpable 3cm at right subcostal region • oliguria, facial edema and edema of lower extremity • shock:gram negative bacillus , microcirculation dysfunction

21. Severe pneumonia --- Toxic encephalopathy • Change of degree of consciousness: - agitation and drowsiness • Cerebral edema • consciousness disturbance • Convulsion • irregular respiratory rhythm • hypertonia anterior fontanel

22. Severe pneumonia ---Digestive system • Mild case : vomit, diarrhea, and abdominal distention • Abdominal distention • gastric distention • due to swallowed air or paralytic ileus • Enlarged liver • downward displacement of right diaphragm • superimposed congestive heart failure • Severe case • toxic paralysis of the intestine • bowel sounds disappear • hemorrhage : melena, hematemesis

23. Severe pneumonia --- Disseminated intravascular coagulation (DIC) • Anemia • Bleeding tendency • bleeding at sites of vein puncture • scattered petechiae over the skin • gastric-intestinal bleeding • Activation of clotting - microvascular and macrovascular thrombosis

24. Complications • Pleural effusions • Pneumatoceles • Empyema • Pneumothorax

25. Laboratory finding---blood test • White blood cell count(leukocyte) • virus →normal or slightly elevated • bacterium ↑ WBC may be normal : when the pathogen is bacterium if the patient is malnutrition or in very severe condition • C reactive protein (CRP) • increase:in bacterial infection • normal: in viral infection

26. Laboratory finding--- Etiologic agent • Isolation of an organism • nasopharygeal secretions (deep coughing, tracheal suction, or pleural fluid obtained at thoracentesis) • Blood culture: bacteria pneumonia • Sputum culture • Pleural fluid • Lung biopsy • Serologic testing：specific antibody to virus

27. Radiologicalfinding • Methodology: • Chest X-ray • Chest CT • Findings: • Viral: hyperinflation, segmental atelectasis, interstitial infiltrates • Mycoplasma : usually lobar • Bacterial: Lobar consolidation, more common in the older child, diffuse infiltrates

28. Radiologicalfinding bronchopneumonia normal lobar pneumonia

29. Radiologicalfinding pleural effusion pneumatocele pneumothorax

30. Diagnosis • Symptoms：fever, cough and tachypnea. • Signs：persistent moistralesin the lung • Chest X-ray：spotted-like or patchy shadows over the lung field • Severe case：Congestive heart failure， Toxic encephalopathy，Toxic intestinal paralysis， DIC • Complications：empyema，pyopneumothorax and pneumatocele

31. Diagnostic Difficulties in Pediatric Pneumonia • Sputum samples are often unobtainable • Some common pathogens are not easily cultured: C. pneumoniae and M. pneumoniae • Nasopharyngeal samples are unreliable due to high asymptomatic carriage rates

32. Differential diagnosis ---Acute bronchitis • Symptoms：mild • Breath sound：coarse，or a few rales(sputum) at the end of inspiration and early expiration. • Chest X-ray：lung markings↑,no spotted or patchy shadows

33. Differential diagnosis ---Bronchial foreign body • History：foreign bodies aspiration, sudden onset of cough and wheezing • Physical signs：bronchial obstruction -complete obstruction ：atelectasis -incomplete obstruction ：emphysema.

34. Differential diagnosis ---Pulmonary tuberculosis • History: recent contact with TB • Toxic symptoms of TB：fever，diminished appetite，weight loss, irritability， malaise，easy fatigability，night sweating • Laboratory test: -Radiogram -ESR↑ -Positive tuberculin test

35. Treatment • Principles of treatment • Control infection • Improve ventilation • Prevent complications

36. General treatment • Good and enough nutrition • Maintain good ventilation : • relieving hypoxia and CO2retention • when the secretion in airway is thick →intermittent ultrasonic inhalant therapy is recommended. • Sputum suction in time：the best way to keep normal ventilation of airway

37. General treatment • Oxygen if indicated • oxygen inhalation can be administrated with nasal cannula, the flow is 0.5-1L/min. • If the hypoxia continues ：Oxyhood may be used with a flow of 2-4L/min. • when respiratory failure occurs ：intubation and ventilation needed • Analgesics and antipyretics • Expectorants

38. Anti-microbial Therapy • Empiric therapy is justified as initial management as the specific bacteriological etiology is unknown and delaying therapy while trying to find a diagnosis may be injurious to the patient

39. Choice of antibiotics • Factors to consider: • The age and any underlying illnesses • The degree of illness and the kinds of bacteria. (the best way →give the most sensitive antibiotic to the bacteria by medicine sensitive test) • Other: spectrum y of activity, pharmacokinetics, dosage, cost, frequency and route of administration, adverse effects, development of resistance • Palatability

40. Choice of antibiotics • Chlamydia Macrolides azithromycin • Mycoplasm azithromycin • Staph aureus clindamycin vancomycin • S. pneumoniae penicillin • H. influenzae amoxicillin • E. coli amoxicillin

41. Duration of Therapy • Total of 7 to 10 days of Antimicrobial therapy • Complications such as pleural effusion or empyema require 2 to 4 weeks of therapy • Staphylococcal empyema is 3 to 4 weeks

42. Other treatment • Treatment of complication: • Pleurocentesis • Surgery

43. Thanks for listening！