The document summarizes various respiratory tract infections, including their etiology, clinical manifestations, treatment and prevention. It discusses upper respiratory infections like the common cold, acute infectious laryngitis and acute bronchitis. It also covers lower respiratory infections such as bronchiolitis, pneumonia caused by different pathogens like RSV, adenovirus and Staphylococcus aureus. Diagnosis, classifications, complications and management of pneumonia are described.

1. The Second Affiliated Hospital of Sun Yat-sen University Tan Wei-ping Infections of the Respiratory Tract

2. Contents Upper Respiratory Infection Acute infectious Laryngitis Acute Bronchitis Bronchiolitis Pneumonia

3. Anatomy upper respiratory tract(URT) Cricoid Cartilage lower respiratory tract(LRT) URT ： Nose 、 pharynx 、 Uvula 、 Larynx 、 auditory tube 、 paranasal sinuses LRT ： Trachea 、 bronchia 、 bronchiole 、 the respiratory bronchiole 、 the alveolar duct and the alveolus

6. Anatomy characteristics upper respiratory tract Nose: cilia↓, capillary↑ Sinuses: mucous Auditory tube tonsil Larynx

7. lower respiratory tract ： Weak Cartilage Supporting , ciliary function impairment Right bronchus :straight , large Collagen and elastin fibers ， capillary ， interstitial tissue Thorax ： chest wall, respiratory muscle ； diaphragm ， mediastinum

8. Physiological characteristics The compensatory ability ↓ Respiratory rate↑ Pattern of respiration Gas-exchanging membrane :diffuse rate CO 2 ＞ O 2 Resistance of airway: child ＞ adult

9. Arterial blood gas examination (1) pH↓acidosis ； (2) PaO 2 ↓ SaO 2 ↓ hypoxemia ； (3)PaCO 2 ↑ carbon dioxide retention mal-ventilation

10. The Immunological Characteristics ： Impaired mucociliary clearance function SIgA↓ 、 IgA↓ 、 IgG↓ subtype of IgG ↓ Alveolar macrophages ↓ , lysozyme ↓ lactoferrin ↓ 、 interferon ↓ complement ↓

11. Upper Respiratory Infection (URI, or Common Cold) 1. Etiology 90% viruses, the majority of colds. rhinoviruses ,coronaviruses. parainfluenza virus, adenovirus, enterovirus, respiratory syncytial virus. 2. season fall and winter 3. Frequency three to eight colds a year.

12. Inoculation by virus Invasion of epithelium of Release of nasopharynx,sinuses and URT cellular damage Inflammatory of nasopharynx mediators in Cholinergic nasal secretions stimulation Increased Increased vascular mucus Permeability production bronchial constriction Nasal Rhinorrhea postnasal Stuffiness drip sore cough throat Pathophysiology of the common cold

13. The clinical manifestation Common cold congestion a runny nose sneezing Cough,sore throat sometimes vomiting and diarrhea Fever,malaise,abdominal pain

14. Specific type of URI Herpangina: coxsackie-viruses group A. summer /fall.High fever, sore throat ， 1-4mm vesicles /ulcers on anterior tonsillar pillars, softpalate,uvula,tonsils pharyngeal wall. Pharyngoconjunctival fever : type 3,7 adenovirus, spring /summer. High fever, sore throat ， pharyngitis, conjunctivitis, cervical lymphadenopathy.

15. Complications sinusitis otitis media cervical lymphadenopathy Mesentery lymphadenopathy retropharngeal abscess pneumonia rheumatic fever acute glomerulonephritis

16. Differential diagnosis Flu Appendicitis Early phase of acute infectious disease

17. Sometimes sore throat Sore throat Fatigue, may persist Mild fatigue severe aches and pains Slight aches and pains Cough, may progress Mild, hacking cough Sometimes sneezing Sneezing Sometimes stuffy nose Stuffy, runny nose Commonly headache Sometimes headache High fever Low or no fever Flu Cold

18. Treatment increased fluid intake avoidance of secondhand smoke Saline nose drops bulb syringe remove the mucus cool mist humidifier antipyretics, such as acetaminophen,ibuprofen, decrease the discomfort of colds. Do not give aspirin (associated with Reye syndrome)

19. Prevention Keep your child away from a person with a cold. Encourage your child to wash his/her hands frequently and not to touch his/her mouth, eyes, or nose until their hands are washed. Make sure toys and play areas are properly cleaned, especially if multiple children are playing together.

20. Acute infectious Laryngitis Etiology Virus or bacteria Typical anatomy

21. Clinical manifestations Barking cough, hoarseness, inspiratory stridor , nasal flaring, suprasternal , infrasternal, intercostal retraction Fever, dyspnea, cyanosis restlessness, tachycardia . Worsen at night. Congestion of pharynx, vocal cord edema

22. Grade of laryngic obstruction Ⅰ ： inspiratory stridor, respiratory difficulty only after activity Ⅱ ： symptoms occurs at rest. tachycardia, rhonchi Ⅲ ： Ⅱ + hypoxia, diminished breath sounds Ⅳ ： exhaustion, lethargy ， pallor , breath sounds diminish or disappear. dull of heart sounds, arrhythmia

23. Diagnosis & differential diagnosis laryngeal diphtheria laryngeal spasm bronchial foreign bodies

24. treatment Maintaining of airway ： steam inhalation, clearing of secretion. antibiotics corticosteroid oxygen supply sedatives (phenergan) Ⅲ ↑ tracheotomy

25. Acute Bronchitis( tracheobronchitis ) Etiology Virus or bacteria Allergy, climate, air pollution, chronic infection of URT, particularly sinusitis. Rickets, malnutrition

26. Clinical manifestations unproductive cough 3~4days -> productive cough, purulent sputum -> 5~10days Chest pain, shortness of breath Vomiting Physical finding: low-grade fever, roughening of breath sounds, rhonchi, coarse moist rales.

27. Asthmatic bronchitis ： ﹤ 3yrs old, eczema, allergy symptoms resemble asthma recurrent episodes reduced after 3~4yrs old.

28. Treatment increased fluid intake frequent shifts of position antibiotics cough suppressants expectorants , antihistamines acetaminophen

29. Bronchiolitis Etiology and epidemiology 50 ％ respiratory syncytial virus(RSV) parainfluenza 3 virus, mycoplasma, adenoviruses north——winter and early spring Guangdong——spring ,summer and early autumn

30. 2.Pathophysiology Lesion: small air passages (diameter75 ～ 300um) Edema, accumulation of mucus and cellular debris, spasm of smooth mussle-> ↑ resistance of small airway ->expiratory difficulty ->overinflation or atelectasis ->hypoxemia, hypercapnia, acidosis

31. Clinical manifestation Infant ﹤2yrs old, peak at 3~ 6 mo of age, male, non breast-feed URI 3 ～ 4days paroxysmal wheezy cough dyspnea develop rapidly mild or moderate fever

32. Physical examination R 60~80/min HR 160 ～ 200/min Nasal flare, intercostal and subcostal retractions Pallor, cyanosis Hyperexpanded chest ， expiratory phase ↑ wheeze ， widespread fine crackles Liver and spleen palpable below the costal margin Critical phase 48 ～ 72h afer onset of dyspnea; recover during 5 ～ 15days

33. Laboratory examination WBC and differential cells count normal Virus detected by antigen detection, PCR, or culture. X-ray: hyperinflation of the lungs, emphysema, scattered areas of consolidation

34. Differential diagnosis Asthma Cystic fibrosis Heart failure Foreign body in the trachea pertussis

36. 两侧肺纹理粗重。两肺中内带多数小斑片状及小结节病灶影。无病灶之肺部透过度增高。

37. Treament Supportive treatment cool, humidified oxygen supply, maintain SaO2 94%~96%; increased fluid intake ： oral intake, intravenous solutions head and chest slightly elevated

38. Ribavirin Antibiotics corticosteroids

39. Pneumonia

40. What’s Pneumonia An abnormal inflammatory condition of the lung infections (bacterial, viral or fungal) chemical injury (gastric acid/ aspiration of food/ hydrocarbon and lipoid pneumonia/ radiation induced pneumonia)

41. Definition Defined by clinical features or with the addition of radiologic findings Tachypnea : indicator of pneumonia(WHO) ＜ 2m, R ≥60/min 2~12m, R ≥50/min ＞ 12m, R ≥40/min sensitivity of 74% and a specificity of 67% compared with radiology

42. Epidemiology A leading killer of children ≤5yr 1.9 million death worldwide/year

43. Etiology Viruses:40% ( ＜ 2yr) Bacteria:27~44% Streptococcus pneumoniae Staphylococcus aureus, Moraxhella catarrhalis, group A Streptococci, and Haemophilus MP, CP:9~14% Mixed:23%

44. Contributing Etiology: risk foctors Malnutrition Rickets Iron-deficiency Immuno-deficency Congenital heart disease Low born bodyweight

45. Clinical manifestation fever cough Dyspnea (Tachypnea,cyanosis) Localized crackles(fine moist rales) Abnormal chest x-ray

46. Classification Pathologic ( anatomic changes) lobar pneumonia : involves a single lobe Bronchial pneumonia : patches around the tubes Interstitial pneumonia : areas between the alveoli Pathogenic ( microorganisms ) bacteria viruses fungi parasites

47. Classification course of disease Acute subacute chronic State of disease common severe

48. Classification Clinical manifestation Typical atipical The combined clinical classification community-acquired pneumonia(CAP) hospital-acquired pneumonia (HAP)

49. Bronchopneumonia 1.Etiology viruses, bacteria, MP, CP. 2~3yrs old 2.pathology edema,infiltration

53. 3 pathophysiology hypoxemia, hypercapnia, toxemia respiratory insufficiency acidosis myocarditis, heart failure, shock, DIC toxic encephalopathy toxic intestinal paralysis

54. 4.Clinical manifestation ( 1) mild (commone)pneumonia ： fever cough dyspnea ( tachypnea, cyanosis) crackles Chest x-ray

55. 两肺纹理增粗。两肺中下野中内带见斑片状阴影，密度较均匀。部分病灶融合成范围稍大的片状影

56. (2) Severe pneumonia ： other systems involved myocarditis heart failure toxic encephalopathy toxic intestinal paralysis

57. Heart failure R ＞ 60/min HR ＞ 180/min Sudden onset of restlesseness,Pallor, cyanosis, delayed capillary refill( ＞ 3~5s) Dull heart sound, gallop rhythm, Jugular vein congestion Liver enlarged rapidly Oliguria or anuria, edema

58. 5.Complications Empyema Pyopneumothorax pneumatocele

59. 6.Laboratory findings: WBC, NBT,CRP Pathogen(antigen and/or antibody) chest x-ray

60. 7.diagnosis Fever, cough, tachypnea, dyspnea, localized fine moist rales, chest x-ray 8.differential diagnosis acute bronchitis tuberculosis foreign bodies of trachea

62. 男 2 岁半。 4 个月前吃蚕豆后发生呛咳，经常发烧，左侧呼吸音低。胸片：左侧阻塞性肺气肿。心 影稍右移，经支气管检查于左支气管取出蚕豆碎块。

64. 9. treament (1) general therapy (2) antipathogen therapy antibiotics antivirus

65. (3)symptomatic therapy oxygen supply airway management abdominal distention fever (4) Corticosteroid (5) complications /underling disease (6)Immunotherapy

66. who should be admitted to hispital

67. Characteristics of pneumonia caused by different pathogen

68. 1.respiratory syncytial virus pneumonia age: 2~7mon fever:mild or moderate main signs: acute onset, wheeze, expiratory difficulty, palpable liver and spleen. Pallor, cyanosis, restlesseness Auscultation: diffuse rhonchi, fine rales Chest X-ray:peribronchial thickening or interstitial pneumonia

69. 2.Adenovirus pneumonia Age: 6mon-2yrs main signs: acute onset, long duration of high fever ， 7~ 10days or 2~3weeks then pelter Systemic toxic symptoms are obvious Frequent cough ， paroxysmal wheeze, dyspnea, cyanosis

70. late appearance of rales(3~7days) myocarditis, heart failure, and encephalopathy X-ray changes early

71. 右肺中上野散在小灶状浸润阴影。左肺野中外带见大片状融合状阴影。其余肺野含气量增高。

72. 3.Staphylococcal aureus pneumonia ＜ 1 year are most commonly affected Acute onset, severe systemic symtoms High fever, respiratory distress, GI . Physical examinations: early appearance of rales Effusion, empyema, pyopneumothorax , abscess of other organs ， Sepsis WBC↑, polymorphonuclear cells ↑ chest x-ray:infiltration, multiple abscesses

75. 4. Gram-negative bacillary pneumonia, GNBP Haemophilus influenza , pneumonia bacilli severe, hard to treament, poor prognosis Systemic toxic symptoms , shock Rales, Infiltration, consolidation, hemorrhagic necrosis X-ray: lobar, or segmental, effusion, abscess DIC

76. 5. Mycoplasma pneumonia Usually over 5yrs, also infant sore throat, headache, myalgia Mild or moderate fever, 1~3weeks Unproductive cough, wheeze in infant Multiple system damage Auscultation: scattered rhonchi or rales. X-ray: “walking pneumonia”, effusions

77. 6. Chlamydial pneumonia (c.Trachomatis) age: 2~12weeks Chronic onset, nasal stuffiness, cough, tachypnea, rales, few wheezes no fever Eye sticky

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