Respiratory Tract Infections Flashcards
(108 cards)
1
Q
What are some URTIs (2)
A
Sinusitis
Tonsilitis
2
Q
What are some LRTIs (5)
A
Bronchitis Pneumonia Empyema Bronchiectasis Lung Abscess
3
Q
What are some respiratory pathologies that make a patient more prone to infection (5)
A
Poor swallow (CVA, muscle weakness, alcohol) Abnormal ciliary function (smoking, viral infection, Kartagner's) Abnormal mucus (CF) Dilated airways (bronchiectasis) Defects in host immunity (HIV, immunosuppression)
4
Q
18 year old woman c/o fever, cough, malaise
Diagnosed with flu by GP. No Abx
Attended A + E
Temp 38 º C
Sats 87% OA
RR 24
Chest- clear Bloods: WCC 40.8, Neut 36.3, CRP 63
CT showed densely consolidated and collapsed left lower lobe
What is the most likely organism?
A
Streptococcus pneumoniae
5
Q
What type of bacteria is streptococcus pneumoniae
A
Gram positive cocci
6
Q
What proportion of CAP is caused by streptococcus pneumoniae
A
30-50%
7
Q
What are the clinical signs of a strep pneumoniae infection (3)
A
Severe pneumonia
Fever, rigors
Lobar consolidation
8
Q
What is the most effective antibiotic for strep pneumoniae
A
Almost always penicillin sensitive
9
Q
What is pneumonia
A
Inflammation of the lung alveoli
10
Q
What is the mortality associated with pneumonia
A
5-10%
11
Q
What percentage of CAP are admitted to hospital
A
20-40%
12
Q
What is the presentation of pneumonia (6)
A
Fever Cough +/- sputum. Pleuritic chest pain Shortness of breath Rigors. Malaise, nausea and vomiting.
There are often localising signs and an abnormal CXR
13
Q
How is pneumonia classified (2)
A
Community-acquired
Hospital-acquired
14
Q
What is the most common cause of hospital acquired pneumonia
A
Ventilator associated
15
Q
What are some underlying factors that predispose to pneumonia (4)
A
Pre-existing lung disease
immuno-compromise
Geography, seasons, epidemics
Travel, exposure to animals
16
Q
What are the main organisms responsible for CAP (5)
A
Streptococcus pneumoniae Haemophilus influenzae Moraxella catarrhalis Staphylococcus aureus Klebsiella pneumoniae
17
Q
What organisms cause pneumonia in 0-3months of age (3)
A
E.coli.
Group B Streptococcus
Listeria
18
Q
What organisms cause pneumonia in 1-6monhs age (3)
A
Chlamydia trachomatis
Staphylococcus aureus
RSV
19
Q
What organisms cause pneumonia in 6months-5 years (2)
A
Mycoplasma
Influenza
20
Q
What organisms cause pneumonia in 16-30 years (2)
A
Mycoplasma pneumoniae
Streptococcus pneumoniae
21
Q
What are most CAP
A
Typical 85%
Atypical 15%
22
Q
What organisms cause typical CAP (2)
A
Streptococcus pneumoniae.
Haemophilus influenzae.
23
Q
What organisms cause atypical CAP (4)
A
Legionella
Mycoplasma (epidemincs 4-6 years)
Coxiella burnetii (Q fever)
Chlamydia psittaci (psittacosis)
24
Q
What are some risk factors for Q fever pneumonia (Coxiella burnetii) (3)
A
Present worldwide
Farm animals
Hepatitis
25
What increases risk of psittacosis
Exposure to birds
26
What are some features of psittacosis (3)
Splenomegaly
Rash
haemolytic anaemia
27
What are the clinical SIGNS of pneumonia (7)
```
Pyrexia
Tachycardia
Tachypnoea
Cyanosis
Dullness to percussion, tactile vocal fremitus
Bronchial breathing
Crackles
```
28
What investigations are indicated in pneumonia (7)
FBC, U&E, CRP
Bacterial cultures, Sputum MC&S
CXR
29
What is the CURB65 score used for
Used to determine if a CAP requires hospitalisation
30
What are the components of the CURB65 score (5)
```
Confusion
Urea >7mmol/L
RR >30
BP <90S, >60D
>65 years
```
31
What CURB65 score warrants hospital admission
Score 2 = ?admit
| Score 2-5 = mange as severe
32
What is bronchitis
Inflammation of medium sized airways
33
Who is prone to bronchitis
Smokers
34
What are the symptoms of bronchitis (4)
Cough
Fever
Increased sputum production
Increased shortness of breath.
35
What can you see on a CXR in bronchitis
Nothing - normal CXR
36
What organisms can cause bronchitis (4)
Viruses
S.pneumoniae
H.influenzae.
M.caterrhalis
37
How is bronchitis managed (3)
Bronchodilation
Physiotherapy
+/- antibiotics.
38
```
56 year old man
Flu-like illness
Presented with cough and fever
Blood-stained sputum
Pyrexial
Not severely unwell
Cavitation of CXR
```
Haemophilus influenzae
39
What is haemophilus influenz
Gram negative coccobacillus
40
What proportion of CAP is due to h.influenzae
15-35%
41
Who is most at risk of h.influenzae pneumonia
More common in those with pre-existing lung disease
42
What must be noted with treating h.influenzae CAP
May produce beta-lactamase
43
```
62 year old man
Presented with SOB
Family also reported recent confusion
Smoker
Satn 91% air
Chest examination normal
Na 124
CXR shows bilateral interstitial changes
```
Legionella pneumophilia
44
How do you acquire legionella CAP
Inhalation of infected water droplets
45
What is the major complication of legionella pneumonia
Can cause multi-organ failure
46
What culture is required to detect legionella pneumonia
Buffered charcoal yeast extract
47
What is atypical pneumonia
Pneumonia caused by organisms without a cell wall
48
What are some organisms which can cause atypical pneumonia (4)
Mycoplasma
Legionella
Chlamydia
Coxiella
49
What antibiotics cannot be used in atypical pneumonias
Cell-wall active antibiotics do not work (e.g. penicilllins)
50
What sort of antibiotics are needed in atypical pneumonias
Agents that work on protein synthesis
51
What are some antibiotic classes that work on protein synthesis (2)
Macrolides
| Tetracyclines
52
Name two macrolides (2)
Clarithromycin
| Erythromycin
53
Name a tetracyclin
Doxycyclin
54
What are some extra-pulmonary features of atypical pneumonias (2)
Hepatitis
| Low sodium
55
What proportion of CAPs are atypical
20%
56
What are two key clinical features of atypical pneumonias (2)
Flu-like prodrome before fever and pneumonia
| Extra-pulmonary complications
57
How is legionella pneumonia spread
Aerosol spread
58
Confusion, abdominal pain, diarrhoea are associated with.....
Legionella pneumophilia
59
How is legionella pneumophilia diagnosed
Antigen in urine/serum
60
What is the best antibiotic for legionella pneumonia
Macrolides (e.g. clarithromycin/erythromycin)
61
How is coxiella burnetti transmitted (2)
Common in domestic/farm animals
| Transmitted by aerosol or milk
62
How is coxiella burnetii diagnosed
Serology
63
What is the best antibiotic class to treat coxiella burnetti
Macrolides
64
How is chlamydia psittaci spread
Spread from birds by inhalation
65
How is chlamydia psittaci diagnoised
Serology
66
What is the best antibiotic class for the treatmetn of chlamydia psittaci
Macrolides
67
74 year old woman
Presented with SOB, fever and right sided pleuritic chest pain
PMH: IHD, CABG, AF
DH: Warfarin
Otherwise well
Examination: T 38.5oC
Reduced persussion note and decreased air entry right base.
Admitted, commenced on cefuroxime and doxycycline. Continued to spike fevers.
Empyema
68
What are some causes why someone with pneumonia may not improve despite being on adequate treatment (6)
```
Empyema/abscess
Proximal obstruction (tumour)
Resistant organism (TB)
Not receiving/absorbing antibiotics
Immunosuppression
Other diagnosis (lung cancer, cryptogenic organising pneumonia)
```
69
```
21 year old male
From Ecuador
Presented with cough, weight loss
U and E normal
Hb 10.4
WC 9.8
LØ 1.1
HIV neg
CRP 173
Alb 31
CXR shows RUZ shadowing
```
Tuberculosis
70
What are some clues for TB as a diagnosis of pneumonia (5)
```
Ethnicity
Prolonged prodrome
Fevers
Weight loss
Haemoptysis
```
71
What is the classical appearance of TB on CXR
Upper lobe cavitation (but can vary considerably)
72
How long does a patient have to have been in hospital to diagnose then with hospital acquired pneumonia
>48 hours in hospital required before diagnosis can be made
73
What are some factors that predispose to hospital acquired pneumonia (2)
Often previous antibiotics
| Ventilator
74
What is the desired investigation in suspected hospital acquired pneumonia
Bronchial lavage desirable to differentiate upper respiratory from lower respiratory flora
75
What are the three most common causes of hospital acquired pneumonia (3)
Enterobacteriaciae - 31%
Staphylococcus aureas - 19%
Pseudomonas spp - 17%
76
```
64 year old retired general
Treated for lymph node Tb
Increasing SOB over one month
Non-productive cough
Chest examination: normal
CXR: bilateral ground glass shadowing
```
Pneumocystis carinii
77
What causes pneumocystis carinii
Protozoan
78
What are the clinical features of pneumocystis carinii (5)
```
Insidious onset
Dry cough
Weight loss
Shortness of breath
Malaise
```
79
What is the classical appearance of pneumocystis carinii on CXR
Bat's wings
80
How is pneumocystis carinii diagnosed
Immunoflouresence of bronchio-alveolar lavage
81
What is the treatment for pneumocystis carinii
Septrin (co-trimoxazole)
82
How can pneumocystis carinii be avoided
Prophylaxis septrin
83
22 year old man
Chemotherapy for leukaemia
Prolonged neutropenia (<1.0)
Ongoing fevers and raised inflammatory markers
Abx: Meropenem, ciprofloxacin, vancomycin, Tazocin, gancyclovir
Interstial changes on CT
Aspergillus fumigatus
84
What are the three forms of aspergillus fumigatus in the lung (3)
Allergic bronchopulmonary aspergillosis
Aspergilloma
Invasive aspergillosis
85
How does allergic bronchopulmonary aspergillosis present (3)
Chronic wheeze, eosinophilia, bronchiectasis
86
How does aspergilloma present (2)
Fungal ball often in pre-existing cavity.
| May cause haemoptysis.
87
Who is at risk of invasive aspergillosis
The immunocompromised
88
What is the treatment for invasive aspergillosis
Amphotericin B
89
What LRTIs are HIV patients at risk of (3)
PCP
TB
Atypical mycobacteria
90
What is the causative organism:
Neutropenia
Immunocompromised
Fungi (e.g. aspergillus spp)
91
What is the causative organism of pneumonia in a patient who has had a bone marrow transplant
CMV
92
What is the causative organism in a patient who has had a splenectomy
Encapsulated organisms (e.g. s.pneumoniae, h.influenzae, malaria)
93
What must be sent before commencing antibiotic treatment in a patient presenting with pneumonia (2)
Sputum/induced sputum
| Blood cultures
94
What organisms can be detected with a urinary antigen test (2)
S.pneumoniae
| Legionella pneumophilia
95
When should you send for a urinary antigen in CAP
If it is very severe
96
What is the use of antibody tests (4)
Only useful on paired serum samples
Usually collected on presentation and 10-14 days later
Look for rise in antibody level over time
Most useful for organisms that are difficult to culture (e.g. chlamydia, legionella)
97
When is immunoflouresence used (4)
Antibody labelled with fluorescent dye
Technique often used in Virology
PCP – Pneumocystis carinii (now renamed P. jiroveci) immunofluorescence is the only common IF test used in microbiology laboratories
May also be detected by Silver stain in cytology lab
98
What antibiotics are effective in gram +ve organisms (5)
```
Amoxycillin
Flucloxacillin
Co-amoxiclav=augmentin
Cefuroxime
Vancomycin
```
99
What antibiotics are effective in gram -ve organisms (4)
Ciprofloxacin
Ceftazidime
Gentamicin
meropenem or piperacillin + taxobactam
100
What antibiotics are effective against atypical organisms (2)
Clarithromycin/doxycycline
101
What antibiotics are usually used in mild-moderate CAP (2)
Amoxicillin
| or erythromycin/clarithromycin
102
What antibiotics are usually used in moderate-severe CAP (2)
Needing hospital admission: augmentin (co-amoxiclav) and clarithromycin
Allergic: cefuroxime and clarithromycin
103
What is first line in treating hospital acquired pneumonia (2)
Ciprofloxacin +/- vancomycin
104
What is second line/ITU for treatment of hospital acquired pneumonia (2)
Piptazobactam and vancomycin
105
What is used to treat MRSA hospital acquired pneumonia
Vancomycin
106
What is used to treat pseudomonas hospital acquired pneumonia (2)
Piptazobactam or ciprofloxacin +/- gentamicin
107
```
21 year old man
No past medical history
Smoker
Drinker
Presented with cough and SOB
Satn 89% on air
Hypotensive
```
How would you treat this patient?
Treated with cef and clarithromycin
Fluid resuscitation (hypotensive)
Supplemental oxygen
Senior support requested
108
How can you prevent pneumonia (2)
Smoking advice
| Vaccination (childhood - immunisation schedule; adults: influenza annually, pneumovax every 5 year)
