1. Infection Diseases of Respiratory System in Children
上海交通大学医学院附属新华医院儿科
鲍一笑

2. Introduction High Morbidity Rate High Mortality Rate
Acute and Chronic Infection
Rheumatic Disease
Pleural Disease
Foreign Body of Airway
Neoplasm
Congenital Anomalies
Each year, respiratory infection diseases cause about 15 million deaths among children younger than age 5 year through the world. This is a significant cause of mortality in childhood. Pediatric pulmonary infection accounts for about 63.89% of all hospitalizations of children, in which 44.6 percent are pneumonia.

3. Anatomy and Physiology
Venting, Warming,
Humidification
and conditioning
Upper respiratory tract ： nose, paranasal sinuses
pharynx, eustachian tube, epiglottis, larynx
Cricoid cartilage
Lower respiratory tract: trachea, bronchi, bronchioles, alveolus
ventilation

5. Anatomy and Physiology
Upper respiratory tract
Short Nasal passages, nasolacrimal duct and eustachian tube
Significance :These characters make nasal cavity easy to become hyperemia, edema, and congestion which will induce infection. Local infection can spread to nearby organs and tissues easily and cause dyspnea, hoarseness and apnea.
Nasal mucosa
Is soft
More vascular
Nasal cavity is short and narrow

6. Anatomy and Physiology
Lower respiratory tract
Narrowed airway
Soft mucous menbrane
More vascular
Softer and more compliant
pulmonary alveoli
sIgA on Respiratory Mucosa
alveolar surfactant
Small amounts
Clinical significance:
Easy to become hyperemia, edema, and congestion
which will induce infection
Complication: Pulmonary emphysema and atelectasis

7. Anatomy and Physiology
The younger the child
The quicker the frequency
The less regular the rhythm
Vital capacity (VC)
Tidal volume
Total lung capacity (TLC)
Small
Respiratory frequency and rhythm ：
The respiratory frequency is inversely related to age .
⑴ neonate : 40～50 bpm；6～12mo: bpm；
1-3 yr : 25～30 bpm；4～9 yr : bpm；
8-14 yr :18～20 bpm。
(2) Some young infants present with irregular rhythm or apnea due to immature respiratory center.

8. Anatomy and Physiology
Thoracic cage
The thorax is barrel shaped. The ribs are in horrizontal position which are almost perpendicular to the spinal column. The location of diaphragm is oppositely superior, which make the size of thoracic cavity decrease, and the size of lung increase.
Respiratory immune function
The specific and nonspecific immune function are poor.

9. Acute Upper Respiratory Infection
Acute Upper Respiratory Tract Infection AURI commonly called “common cold”

10. Introduction
The common cold is the most common pediatric disease and accounts for 80-90% proportion of visit to clinic.
Local infection may spread to nearby organs and tissues which will likely to cause otitis media, conjunctivitis, lymphadenitis, lymphadenitis and pneumonia.
Bronchial asthma, nephritis, myocarditis, measles and pertussis may also follow AURI

11. Etiology 90% of AURI are caused by viral infection Rhinovirus
Echo virus
Coxsackievirus
Parainfluenza
Influenza
Adenovirus
RSV(Respiratory Syncytial Virus)
90% of AURI are caused by viral infection

12. Haemophilus influenzae Staphylococcus aureus
Bacteria
Pneumococcus
Moraxelle catarrhalis
Haemophilus influenzae
Staphylococcus aureus

13. Others
Mycoplasma
Chlamydia
Other Microorganisms

14. Clinical Manifestation
Mild symptom
Nasal congestion, rhinorrhea,
sneezing, sore throat
Severe symptom
High fever, convulsion,
anorexia,frequency cough

15. Symptoms of URI in children of different ages
< 3 mo
Infants
Adolescents
Systemic
symptom
Usually mild
Low grade fever
Usually severe
High fever
Convulsion
Irritability
Respiratory
Symptoms
Nasal congestion
Dyspnea
Absent
or mild
or severe
Rhinorrhea
Sneezing
Sore throat
Gastrointestinal
Diarrhea
Vomiting
Anorexia
Abdominal Pain

16. Physical Sign The pharynx is red Retropharyngeal folliculosis
Erythematous enlarged tonsils
Enlarged lymph nodes
Enterovirus illnesses may be associated with a wide variety of skin rashes

17. Two Special Type Herpangina Coxsackievirus A
Most often occurs in summer and autumn
More often in infants（0-3 yr of age）
Characterized by sudden onset of fever, sore throat and dysphagia
Characteristic lesions, present on the posterior pharynx, are discrete vesicles and ulcers
Duration of illness is usually 7 days

18. Pharyngoconjunctival Fever
Occurs typically with type 3,7 adenovirus
Most often occurs in spring and summer
Children （>3 yr ） more often affected
Features include:
A high temperature that lasts 4–5 days, pharyngitis, conjunctivitis, cervical lymphadenopathy, and rhinitis.
Duration of illness is usually 1-2 weeks

19. Complication Viral Infection → Viral Myocarditis Viral Encephalitis
Otitis media
Cervical lymphadenitis
Bronchitis
Pneumonia
Septicemia
Viral Infection
→ Viral Myocarditis Viral Encephalitis
Bacterial Infections（streptococcus))
→ Acute Nephritis Rheumatic Fever

20. Diagnosis
Clinical manifestations
Symptoms and sighs

21. Differential diagnosis
The differential diagnosis of the URl includes other acute infectious disease.
In patient with febrile convulsion, central nervous system Infections should also considered.
Patients with abdominal pain may have acute abdomen.

22. Difference Between Mesenteric Lymphadenitis and Acute appendicitis
Clinical Manifestation
Mesenteric lymphadenitis
Acute appendicitis
Symptom of URI
exist
absent
Fever and
Abdominal Pain
1st present with: fever
Follow : pain (mild)
1st present with : pain (severe)
Follow : Low grade fever
Abdomen signs
Diffuse tenderness
No rebound tenderness and guarding
Progressive localized abdominal tenderness
With rebound tenderness and guarding
Blood routine
WBC is usually normal or elevated
WBC is elevated
higher level of neutrophils

23. Prophylaxis Increase outdoor activities. Improve physical fitness.
Enhance immunity function.
Patients in collective institutions
should be isolated.

24. Treatment General treatment Etiological treatment
Anti-virus：Ribavirin
Avoid the abuse of antibiotics
Symptomatic treatment
Severe nasal obstruction
Irritability-restlessness
High fever
Pharyngeal portion ulcer
Conjunctivitis

25. Summary
Upper respiratory infection is the most common disease in childhood
most of which are caused by viral infections.
The severity of clinical manifestations is related to age of the patients.
Infants present mild local symptoms and severe systemic symptoms, while older children present on the contrary.
A stuffy, congested nose may exist in infants younger than 3 months of age.
Treatment for the common cold should be mainly symptomatic. Antibiotics should not be used unless in those young, infant patients which are suspected to complicate bacterial infections.

26. Acute Bronchitis
Acute bronchitis is inflammation of the tracheobronchial epithelium .
Trachea is usually involved，so acute bronchitis is also called ‘acute tracheobronchitis’.
Acute bronchitis is commonly secondary to an acute viral infection, or just one manifestation of acute infectious disease.

27. Etiology
Infectious factors：viral, bacterial or other pathogen infections
Characters of respiratory tract of infants: The mucous become edema and hyperemia which make the bronchus narrower when inflammation.
Other factors：immunodeficiency, nutritional diseases, specific body constitution.

28. Clinical Manifestation
Begins as an URI
Cough is a significant signs nonproductive cough→ productive
The systemic symptoms is usually serve in infants including fever, vomiting and diarrhea
Medical examination：
Respiratory rudeness
Diffuse or scattered rales
No dyspnea
CXR : may be normal
or thickening lung markings

29. Summary
Acute bronchitis is an inflammation of the major conducting airways within the lung which caused by viral or bacteria, and is most often in infants. Cough is the most significant clinical manifestation. Fever, vomiting and diarrhea are frequent in infants. Respiratory sounds are rough and scattered rales are heard on auscultation. Radiographic examination of the chest may show a mild increase in bronchovascular markings. Antibiotics are indicated if a bacterial infection of the airway is suspected or proven. Corticosteroids are recommended in severe cases.

30. Acute Pneumonia
Pneumonia is an inflammation of the parenchyma of the lungs.
Most cases of pneumonia are caused by microorgnanisms, but there are several noninfectious causes, which include aspiration of food or gastric acid, foreign bodies and so on.

31. Epidemiology Season of onset Age of onset Morbidity rate
Mortality rate

32. Category
Classified according to the infecting organism: Viral pneumonia, bacterial Pneumonia, mycoplasma Pneumonia. Classified according to Pathology: Bronchopneumonia, lobar pneumonia,interstitial pneumonia. Classified according to duration of disease: Acute pneumonia(<1 mo), persistent pneumonia(1-3 mo) and chronic pneumonia(> 3mo). Classified according to severity of disease: Mild pneumonia and severe pneumonia.

33. Etiology Viruses others Bacteria
Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus,　Escherichia coli, Pseudomonas pyocyanea
Viruses
Respiratory Syncytial Viruses,
adenovirus, influenza, parainfluenza
others
Incidence rate of Chlamydia pneumoniae
and Mycoplasma pneumoniae are
increasing recent years.

34. Inducement Age Disease Environment
Patients with the following problems are particularly predisposed to this disease:
Age
More often in infants
Disease
Malnutrition, Congenital heart disease, Immunodeficiency disease
Environment
The recidence is wetness, stuffiness and crowding.

35. Pathology
Hyperemia, edema and inflammatory infiltration of lung tissues
Alveolar exudate
Patchy Inflammation focus, and consolidation
Atelectasis and emphysema of lung

36. Clinical Manifestion four symptoms Rales cough Fever tachypnea
pneumonia
symptoms
Rales
tachypnea

37. Severe Pneumonia
Apart from the general features of bronchopneumonia, severe pneumonia also present with systemic toxic symptoms in respiratory system, circulatory system, nervous system and digestive system.

38. Extrapulmoanry presentations
Intracranial hypertension
Encephaledema
Nervous system
Myocarditis, heart failure
Microcirculation disturbance
Circulatory system
Gastrointestinal dysfunction, enteroplegia
Alimentary tract hemorrhage
Digestive system
Mixed acidosis, dehydration
Hyponatremia
Water-Electrolyte Balance

39. Myocardial failure
Suddenly onset of tachypnea, R>60 bpm, increased pulmonary rales.
Tachycardia that can not be explained by high fever or tachypnea, HR>180 bpm
Irritability and cyanosis
Gallop rhythm or dull heart sound , distension of jugular vein and enlarged cardiac
Increased liver with tenderness, > 1.5cm.
 Oliguria or anuria that present with edema of eyelid or lower extremities.

40. Complication Empyema of pleura Others：Septicemia Purulent pneumothorax
Bullae of lung
Others：Septicemia
Purulent pericarditis

41. Laboratory Examination
Peripheral blood examination
　　　　　　　　White cell count
CRP (C-reactive protein)
Nitroblue tetrazolium test
Etiological examination
Bacteriological examination ：
Bacterial culture
Virological examination：
Viral isolation
Examination of mycoplasma：
Specific immunity examination

42. Lobular pneumonia (Bronchopneumonia)
Pathogen
Streptococcus pneumoniae
Haemophilus influenzae
Pathology
Pathological changes such as hyperemia and edema of bronchiolar wall, exudation of pulmonary lobule, and bronchiolar obstruction are scattered surround bronchus.
Clinical manifestation
Hyperpyrexia, cough, tachypnea and dyspnea
More common in infants, aged people and weak people

43. Chest radiographic findings in bronchopneumonia
Increase lung markings
Diffuse bilateral Patchy infiltrates and consolidation scattered throughout both lungs
Atelectasis, hyperinflation,
bullae of lung and pyothorax

44. Chest radiographic findings in bronchopneumonia
Frontal views :
Patchy infiltrates and consolidation at the inner zone and middle zone of bilateral lower lobes, with or without hyperinflation

45. Segmental atelectasis
Frontal views :
It is a segmental atelectasis at the right superior lobe. The transversa fissure is displaced toward the airless lobe. There is a sector high density shadow with the apex toward the hilum of lung. The diaphragm is elevated and the mediastinum is shifted to the side of involvement.

46. Lobar pneumonia Pathogen: maily streptococcus pneumoniae
Pathology : inflammtion infiltrates throughout a whole lobe or segment of the lung.
Main clinical manifestation:
More common in adolescence, rare in young children.
Hyperpyrexia, cough, and rusty sputum
X-ray findings Change after changes of clinical symptoms.

47. Lobar pneumonia at middle lobe of right lung
Frontal views :
A consolidation within the transverse fissure and oblique fissure can be seen at the middle lobe of right lung,

48. Bronchiolitis viral disease, RSV (85%). aged 2-6 months.
airway obstruction is due to pathological changes include swelling and distension of bronchioles, secretions blockage.

49. Clinical Manifestation
expiratory wheezing
tachypnea, nasal flaring
Cyanosis
fine rales
emphysema
The duration of illness is 4 ~ 7 days

50. Chest radiographic findings
Hyperexpansion is commonly present
Peribronchial cuffing
Increased interstitial markings
Patchy infiltrates

51. RSV Pneumonia Frontal views of CXR: Ground-glass opacity
Decreased lung markings
Patchy infiltrates in innner and middle zone
Acquired hyperinflation

52. Pneumonia of newborn
Escherichia coli is the most common pathogen in neonate. In young infants > 1 week, mainly pathogen are staphylococcus aureus and hemolytic streptococcus.
Some patients may present only with signs of generalized toxicity. Patient uauslly present no cough or fever. Rales are seldom heard on ausculation. Clinical manifestation may be milk-resistant, drowsiness, low response, and tachypnea.
Cyanosis, foaming at mouth, nodding respiration or apnea may present in severe cases.
Respiratory signs is rare.

53. Chest X-ray Frontal views :
There is patchy shadows and infiltrates at right lung field.

54. Adenovirus pneumonia Type 3,7 adenovirus
Young children（6 mo-2 yr ）are more often affected
Acute onset of high fever, toxic symptoms and pale face. Sometimes present with cardiac dysfunction and symptom of nervous system
Severe cough, dyspnea and wheezing
Respiratory signs such as fine rales occur after 3-4 days
Patchy infiltrates and consolidation with hyperinflation.

55. Adenovirus pneumonia Frontal views :
Chest radiographs reveals diffuse interstitial and patchy alveolar infiltrates, peribronchial thickening, and focal consolidation throughout both lung field.

56. Staphylococcal pneumonia
More common in neonate and infants
Present a sudden onset and progress quickly
Signs include: rashes, severe toxic symptoms, digestive symptoms, convulsion and shock
Signs vary with stage of disease
Consolidation of lung is obvious
Chest X-ray reveals infiltrates, abscess and bullae of lung

57. Abscess of lung Frontal views :
Multiple round high density shadow in both sides

58. Pyopneumothorax

59. Encapsulated pleural effusion

60. Pulmonary Bulla Female，7 day，hyperpyrexia and no crying
CXR: multiple giant
air-containing cavity

61. Mycoplasma pneumonia
Common cause of symptomatic pneumonia in older children
Fever, dry cough are common symptoms
Extrapulmonary complications sometimes occur
Chest radiographs are untypical, usually demonstrate interstitial or bronchopneumonic infiltrates

62. Interstitial infiltrates in Mycoplasma pneumonia
A 5-year-old boy
complain of fever and cough.
MP antibody (+)
Frontal views of CXR:
Increased lung markings
Diffuse patchy infiltrates
Volume loss of lower lobes of bilateral lung
Enlarged hilar shadow

63. Diagnosis Peak age of onset Clinical manifestation
Laboratory examination
X-ray examination
Others

64. Differential Diagnosis
Acute bronchitis
Pulmonary tuberculosis
Foreign body in bronchus

65. Treatment Nursing and supporting therapy Symptomatic treatment：
Oxygen supply Conscious sedation
Pyretolysis Cough suppressants
Eliminate sputum
Antimicrobial therapy
Treatment of complication
Enhance immunity function
physical treatment

66. Antimicrobial treatment
Principle of antibiotic treatment:
Sensitive
Early treatment
Sufficiency
Drug combination

67. Antibiotic treatment Streptococcus pneumoniae penicilin Amoxicillin
Bacillus influenzae
Amoxicillin plus clavulanate
2nd or 3rd-generation cephalosporins
Staphylococcus aureus
Oxacillin sodium
Vancocin
Moraxelle catarrhalis
Mycoplasma Pneumonia
Erythromycin Macrolide

68. Antiviral treatment There is no ideal drug in antiviral therapy.
Ribovirin
interferon (IFN)
Human Immunoglobulin
Traditional chinese drug therapy
Yuxingcao, Double coptis

69. Indication of Systemic corticosteroids
Severe toxic symptom that include shock,
ultrahyperpyrexia and toxic encephacopathy
Increased secretions and bronchial spasm
Complicated with pleural effusion in early period

70. Treatment of severe pneumonia
Heart failure：
cardiotonic, sedative
diuresis and oxygen supply
Respiratory Failure：
suctioning, oxygen supply
intubation and artificial respirator
Toxic encephacopathy：
anti-infection, oxygen supplY,
correct acidosis

71. Summary
Fever, cough, tachypnea and fine rales are four major symptoms of pneumonia.
Besides, severe pneumonia present circulatory, neurological and digestive symptoms
Diagnosis mainly depends on clinical manifestations and X-ray examination.
According to the characteristics of clinical symptoms, signs and auxiliary examination, we classify different type and severity.   
Treatment should emphasize comprehensive treatment.
Choose different antibiotics according to different pathogens.
Pay attention to the importance of nursing, supporting therapy, and symptomatic therapy.

72. Thanks!