Respiratory Tract Infection Flashcards
(159 cards)
1
Q
Types of microorganism pathogenicity
A
Primary
Facultative
Opportunistic
2
Q
What is primary pathogenicity?
A
If the microorganisms infect everybody
3
Q
What is facultative pathogenicity?
A
Need a bit of help - predisposing conditions
4
Q
What determines the capacity to resist infection?
A
Stage of host defence mechanisms
Age of patient
5
Q
Is the upper respiratory tract sterile?
A
No
6
Q
Is the lower respiratory tract sterile?
A
Yes
7
Q
What does resistance to organisms decrease with?
A
Age
8
Q
Examples of URTIs
A
Coryza
Sore throat syndrome
Acute laryngotracheobronchitis
Laryngitis
Sinusitis
Acute epiglottitis
9
Q
What is coryza?
A
Common cold
10
Q
Another name for acute layrngotracheobornchitis
A
Croup
11
Q
Who gets acute epiglottitis?
A
Young children
12
Q
Causative organism of acute epiglottitis
A
Group A beta haemolytic streptococci
Haemophilus influenzae type b (Hib)
13
Q
Examples of LRTIs
A
Bronchitis
Bronchiolitis
Pneumonia
14
Q
Respiratory tract defence mechanisms
A
Macrophage mucociliary escalator system
- alveolar macrophages
- mucociliary escalator
- cough reflex
- particle clearance from lungs
General immune system (humoral and cellular)
Respiratory tract secretions
Upper resp tract acts as filter
- nose hair
- warms and humidifies air
15
Q
Other exit routes for macrophages
A
Alveolar wall into lymphatic system
16
Q
When can the mucosal ciliary escalator fail? What may this result in?
A
During viral infections
Viruses / foreign bodies retained in the lungs
17
Q
What is a common reason to get bacterial lung infections?
A
Virus infections damage the epithelium and cause damage to the mucosal ciliary escalator
18
Q
Aetiological classification of pneumonia
A
Community acquired
Hospital acquired (nosocomial)
Pneumonia in the immunocompromised
Atypical
Aspiration
Recurrent
19
Q
What is atypical pneumonia?
A
Pneumonia caused by unusual infectious agents
20
Q
Patterns of pneumonia
A
Bronchopneumonia
Segmental
Lobar
Hypostatic
Aspiration
Obstruction
21
Q
What is bronchopneumonia?
A
Acute inflammation of the walls of the bronchi with adjacent bits of lung infected
22
Q
What is segmental pneumonia?
A
Segment of the lung
23
Q
What is lobar pneumonia?
A
Affects a lobe of the lung
24
Q
What is hypostatic pneumonia?
A
Patient lots of accumulation of secreted fluid - usually due to bronchitis producing mucus or cardiac failure
25
What does bronchopneumonia look like on CXR?
Bilateral basal patchy opacification - relating to the focal nature of consolidation
26
Complications of pneumonia
Pleurisy
Pleural effusion
Empyema
Mass lesion
COP
Constrictive bronchiolitis
Lung abscess
Bronchiectasis
27
What is pleural effusion?
Fluid in pleural space
28
What is COP?
Cryptogenic organising pneumonia (BOOP)
29
What is bronchiectasis?
Pathological dilatation of the bronchi
30
Causes of bronchiectasis
Severe infective episode
Recurrent infections
Proximal bronchial obstruction
Lung parenchymal destruction
31
What % of bronchiectasis starts in childhood?
75%
32
Presentation of bronchiectasis
Cough
Abundant purulent foul sputum
Haemoptysis
Signs of chronic infection
33
Signs of bronchiectasis
Coarse crackles
Clubbing
34
Ix of bronchiectasis
CT
35
Treatment of bronchiectasis
Postural drainage
Antibiotics
Surgery
36
Causes of aspiration pneumonia
Vomiting
Oesophageal lesion
Obstetric anaesthesia
Neuromuscular disorders
Sedation
37
Possible causes of recurrent lung infection
Local bronchial obstruction (tumour/foreign body)
Local pulmonary damage (e.g. bronchiectasis)
Generalised lung disease (CF or COPD)
Non resp disease (immunocompromised / aspiration etc)
38
Types of organisms causing opportunistic infections
Low grade bacterial pathogens
CMV
Pneumocystitis jirovecci
Fungi and yeasts
39
Air flow in airways
Bulk flow
- laminar (parallel)
- turbulent (irregular)
40
What happens beyond the terminal bronchiole?
Diffusion
41
Normal PaO2
10.5 - 13.4 kPa
42
Normal PaCO2
4.8 - 6.0 kPa
43
Types of respiratory failure
Type 1
Type 2
44
Type I resp failure
PaO2 < 8kPa
Pa CO2 normal or low
45
Type II resp failure
PaCO2 > 6.5kPa
Pa02 usually low
46
What are the 4 abnormal states associated with hypoxaemia?
Ventilation / perfusion imbalance (V/Q)
Diffusion impairment
Alveolar hypoventilation
Shunt
47
Pulmonary vascular changes in hypoxia
Physiological pulmonary arteriolar vasoconstriction
48
Pathology of pneumonia causing hypoxaemia
Ventilation/perfusion abnormality (mismatch)
- some ventilation of abnormal alveoli, but not enough
Shunt
- severe bronchopneumonia
- no ventilation of abnormal alveoli
- blood passing from R to L shunt of heart without contacting ventilated alveoli
49
When do pathological shunts occur?
AV malformations
Congenital heart disease
Pulmonary disease
50
Pathology of COPD causing hypoxaemia
Ventilation perfusion abnormality - airway obstruction
Alveolar hypoventilation
- reduced resp drive
- entire lung volume not being ventilated well
- increased PaCO2
Diffusion impairment - loss of alveolar surface area
Shunt
- only during acute exacerbation
- area of lung tissue that is completely airless which has no ventilation to it because the lung is either obstructed or consolidated
51
The concentration of CO2 and H in where makes us breath in and out?
CSF
52
COPD patients effect on their respiratory drive
Patients who live in a chronic hypoxic situation despite the best efforts of the kidney means the respiratory centre loses the drive from the CO2 and the H ions
Patients with COPD rely on hypoxia to give them more of a resp drive (therefore have to manage how much oxygen you give them)
53
What is cor pulmonale?
Right sided heart failure due to pulmonary HTN
54
Pathology of cor pulmonale
Pulmonary vasoconstriction
Pulmonary arteriole muscle hypertrophy intimal fibrosis
Loss of capillary bed
Secondary polycythaemia
Bronchopulmonary arterial anastomoses
Chronic
- hypertrophy of R ventricle
55
Examples of URTIs in children
Rhinitis
Tonsillitis
Otitis media
Pharyngitis
Tacheitis / LTB
Laryngitis
Epiglottitis
56
Viral infective agents causing URTIs in children
Adenovirus
Influenza A and B
Para flu I, III
RSV
Rhinovirus
57
What does RSV stand for?
Respiratory syncytial virus
58
Bacterial causes of URTIs in children
H influenzae
M catarrhalis
Mycoplasma
S aureus
Streptococci
- B haemolytic
- S pygoenes
- non haemolytic S pneumoniae
59
What is rhinitis?
Inflammation of mucous membrane inside nose
60
When does rhinitis occur?
Winter months
61
Is rhinitis self limiting?
Yes
62
What can rhinitis be a prodrome for?
Pneumonia
Bronchiolitis
Meningitis
Septicaemia
63
What is otitis media?
Ear infection
64
Presentation of otitis media
Bulging drum
Pain
65
Is otitis media self limiting?
Yes
66
Causes of otitis media
Primary viral infection
Secondary infection
- pneumococcus
- H flu
67
What can otitis media lead to?
Spontaneous rupture of drum
68
When should otitis media be treated?
Severe uni and bilateral > 6 months
Severe pain > 48 hours
69
Treatment of otitis media
ANALGESIA
70
Investigations of tonsillitis/pharyngitis
Throat swab
71
Treatment of tonsillitis/pharyngitis
Nothing
10 days penicillin
72
What must NOT be given in tonsillitis?
Amoxicillin
73
Causative organism of Croup/LTB
Para influenza I
74
Presentation of croup
Coryza
Stridor
Hoarse voice
Barking cough
Very well
75
Treatment of croup
Oral dexamethasone
76
Causative organism of epiglottis
H influenzae type B
77
How common is epiglottitis?
Rare
78
Presentation of epiglottitis
Stridor
Drooling
79
Treatment of epiglottitis
Intubation
Antibiotics
80
What % of URTIs in children are self limiting?
>99%
81
What are the lower resp tract infections in children?
Pneumonia
Tracheitis
Bronchitis
Empyema
Bronchiolitis
82
Common infective agents of LRTI in children
Strep pneumoniae
H influenzae
Moraxella catarrhalis
Mycoplasma pneumoniae
Chlamydia pneumonia
RSV
Para influenzae III
influenzae A and B
Adenovirus
83
Presentation of tracheitis
"Croup which doesn't get better"
Fever
Sick child
Off food
Lethargic
84
Causative organisms of tracheitis
Staph
Strep
85
Treatment of tracheitis
Augmentin
86
How common is bronchitis?
Very very common
Mostly self limiting
87
Presentation of bronchitis
Loose rattly cough with URTI
Post tussive vomit (glut = mucous stuff)
Chest free of wheeze / creps
Child very well
88
Causative organisms of bronchitis
Haemophilus
Pneumococcus
89
What is bronchitis an infection of?
Endobronchium
90
Pathology of bacterial bronchitis
Disturbed mucociliary clearance
1. minor airway malacia
2. RSV/adenovirus
Lack of social inhibition
Infection secondary (so no Ax)
91
How long does bronchitis last for?
4 weeks
92
What does bronchitis follow?
URTI
93
Criteria for persistent bacterial bronchitis
Wet cough
More than one month
Remission with Ax
94
What kind of diagnosis is bronchiolitis?
Clinical
95
What is bronchiolitis?
LRTI of infants
96
What % of infants get bronchiolitis?
30 - 40%
97
Causative organisms of bronchiolitis
RSV
Others
- paraflu III
- HMPV
98
What does RSV stand for?
Respiratory sinsitium virus
99
Presentation of bronchiolitis
Nasal stuffiness
Tachypnoea
Poor feeding
Crackles +/- wheeze
100
Does bronchiolitis have a predictive history?
YES
101
Who gets bronchiolitis?
< 12 months old
102
Is bronchiolitis recurrent?
NO
103
What day after the start of cough does bronchiolitis start to stabilise?
Day 5 - 7
104
How long does the whole illness of bronchiolitis last?
2 weeks
105
Management of bronchiolitis
Maximal observation
Minimal intervention
106
Investigations of bronchiolitis
NPA (cohorting)
Oxygen sats
107
Treatment for bronchiolitis
NONE
Oxygen
108
What does NPA stand for?
Naso pharyngeal aspirate
109
What does O2 sats in bronchiolitis indicate?
Severity
110
Presentation of a LRTI
48 hours
> 38.5 degrees temp
SOB
Cough
Grunting
Reduced or bronchial breathing sounds
111
Wheeze indicates what is UNLIKELY?
A bacterial cause
112
Does bronchiolitis cause fever?
NO
113
Call the LRTI pneumonia if.....
1. Signs are focal
2. Creps (fine crackles)
3. High fever
114
How to confirm diagnosis of LRTI/Pneumonia
CXR
115
Management of community acquired pneumonia in children
Nothing if symptoms are mild
Oral amoxycillin first line
Oral macrolide second line
IV if comiting
116
Do you treat bronchiolitis with Ax?
NO
117
Do you treat croup with Ax?
NO
118
Do you treat acute LRTI with Ax?
Often not indicated
Amoxicillin first line if are treated
119
Do you treat otitis media with Ax?
Not usually indicated
Consider amoxicillin if
- < 2 y/o
- bilateral infection
120
Do you treat pharyngitis/tonsillitis with Ax?
Not indicated usually
Can consider penicillin
121
What is the other name for pertussis?
Whooping cough
122
What reduces the risk and severity of pertussis?
Vaccination
123
Presentation of pertussis
Coughing fits
Vomiting
Colour change
124
What is empyema a complication of?
Pneumonia
125
What is empyema?
Extension of the infection into the pleural space
126
Presentation of empyema
Chest pain
Very unwell
127
Treatment of empyema
IV Antibiotics
Drainage
128
Do children with empyema have a good prognosis?
Yes
129
What organism commonly creates a cavitating pneumonia in the upper lobes, particularly in DM and alcoholics and may also be caused by aspiration?
Klebsiella pneumoniae
130
Features of pneumoniae caused by legionella
Dry cough
Atypical chest signs
Hyponatraemia
Lymphopenia
131
Causative organism of pneumonia following influenza
Staph aureus
132
Who is pneumonia caused by pneumocystitis jiroveci seen in?
HIV patients
133
Which organism accounts for 80% of pneumonia cases?
Strep pneumonia
134
Features of strep pneumoniae
High fever
Rapid onset
Herpes labialis
135
Is there a vaccine against step pneumoniae?
Yes - pneumococcus
136
What type of pneumonia particularly occurs in patients with COPD?
Haemophilus influenzae
137
Give an example of an atypical pneumonia
Mycoplasma pneumoniae
138
Presentation of mycoplasma pneumoniae
Dry cough
Atypical chest signs / Xray findings
Autoimmune haemolytic anaemia
Erythema multiforme
139
Presentation of PJP
Dry cough
Exercise induced desaturations
Absence of chest signs
140
What is idiopathic interstitial pneumonia? Give an example
A group of non infective causes of pneumonia
Examples include cryptogenic organising pneumoniae
141
What is cryptogenic organising pneumoniae?
A form of bronchiolitis which may develop as a complication of RA or amiodarone therapy
142
Presentation of pneumonia
Cough
Sputum
SOB
Chest pain; may be pleuritic
Fever
Signs of SIRS
Reduced O2 sats
Reduced breath sounds / bronchial breathing
143
What is the classical Xray finding of pneumonia?
Consolidation
144
What is the risk stratification score called used for patients with community acquired pneumonia?
CURB-65
145
What are the parts of CURB-65?
C = confusion
U = urea > 7
R = Resp rate > 30
B = BP < 90/<60
65 = Age > 65
146
Management of patient with a CURB 65 score of 0
Should be managed in the community
147
Management of a patient with a CURB 65 score of 1
Can be managed in community if sats > 92% and a CXR done
Hospital admission advised if on CXR - bilateral/multilobular shadowing
148
Management of a patient with a CURB 65 score of 2
Management in hospital as this indicates a severe community acquired pneumonia
149
What is ARDS caused by?
Increased permeability of alveolar capillaries leading to fluid accumulation in the alveoli i.e. non cardiogenic pulmonary oedema
150
Mortality of ARDS
40%
151
Causes of ARDS
Infection; sepsis, pneumonia
Massive blood transfusion
Trauma
Smoke inhalation
Acute pancreatitis
Cardio pulmonary bypass
152
Presentation of ARDS
Acute onset and severe
SOB
Elevated RR
Bilateral lung crackles
Low O2 sats
153
Key investigations for ARDS
CXR
Blood gas
154
Management of ARDS
Oxygen
General organ support e.g. vasopressors as needed
Treat underlying cause
155
What is the centor criteria involved with?
Sore throat
If 3 or more of the criteria is present, 40 - 60% chance the sore throat is caused by Group A beta haemolytic streptococcus
156
Parts of the centor criteria
Presence of tonsillar exudate
Tender anterior cervical lymphadenopathy or lymphadenitis
History of fever
Absence of cough
157
NICE guidelines on timeline of treatment and recovery of Community acquired pneumonia
Week 1 - fever should resolve
Week 4 - chest pain and sputum should have significantly reduced
Week 6 - cough and SOB should have significantly reduced
Month 3 - most symptoms should have resolved, except from tiredness
Month 6 - should be returned to normal
158
Only indication for surgery in bronchiectasis
Localised disease on CT
159
When should you consider granulomatosis with polyangiitis (wegeners)?
When a patient presents with ENT, resp and renal involvement
