Respiratory Tract Infections

Question 1

what are saliva and mucous membranes membranes designed to do

Answer 1

absorb bio particles and bacteria

there is also iGA antibodies in the saliva mucous membranes

Question 2

what are the different types of upper respiratory type infections

Answer 2

sinusitis
tonsilitis
pharyngitis

Question 3

what is sinusitis

Answer 3

inflammation of sinuses

Question 4

why is sinusitis more common in certain people than others

Answer 4

sinuses are different from person to person

some are more predisposed to build up of mucous which creates a nice growth environment for bacteria

Question 5

what type of infection are tonsillitis and pharyngitis

Answer 5

viral
uncomfortable
antibiotics are normally given but they shouldn’t be
first port of call is to self medicate

Question 6

what are common viruses that cause upper respiratory tract infection

Answer 6

rhinovirus
parainfluenza
epstein barr virus
herpes simples types 1 and 2

Question 7

what are the bacteria that cause upper respiratory tract infections

Answer 7

streptococcus pyogenes

Question 8

where is iGA found

Answer 8

main immunoglobulin found in mucous secretions from tear glands, salivary glands, mammary glands, the respiratory system, GU tract and GI tract

Question 9

what is iGA produced by

Answer 9

B lymphocytes

Question 10

what are alveolar macrophages

Answer 10

primary phagocyte of the innate immune system, clearing the air spaces of infectious, toxic or allergic particles that have evaded the mechanical defenses of the respiratory tract

Question 11

what are examples of viruses that cause upper respiratory tract infections

Answer 11

rhinovirus
influenza
epstein barr virus
herpes simples types 1 and 2

Question 12

what are examples of bacterias that cause upper respiratory tract infections

Answer 12

streptoccocus pyogenes

c. diphtheria
h. influenza
b. vincenti

Question 13

how often is tonsiltiis/pharyngitis caused by a virus

Answer 13

70%

Question 14

what else can tonsillitis/pharyngitis be caused by

Answer 14

common cold (rhinovirus, adenovirus, parainfluenza + others)
glandular fever

Question 15

what is the pathogenesis of the common cold

Answer 15

1. We start off by breathing in the virus
2. The virus attaches to the epithelium and gets into the cell
3. It divides rapidly
4. Cell damage occurs as the immune system realizes that the cell is infected causing it to go into apoptosis or it may become necrotic
5. Macrophages come along to try and tidy things up

Question 16

what happens in the recovery of the common cold

Answer 16

interferon and antibody production occurs

Question 17

what causes 25% of sore throat

Answer 17

streptococcus pyogenes (group A)

Question 18

why does S. pyogenes show up in a blood agar

Answer 18

it haemolyses blood

Question 19

what does group A strep produce

Answer 19

produces extracellular substances and essentially these are exotoxins that break up cell membranes, blood cells, collagen fibres ect making it a nasty organism

Question 20

what are group A strep virulence factors

Answer 20

 Pyrogenic exotoxins
 Streptolysins
 Hyaluronidase
 M protein

Question 21

what is the group A capsule made up of

Answer 21

hyaluronic acid and it is a protective mechanism

Question 22

how can streptococcus pyogenes cause rheumatic fever

Answer 22

It can cause streptococcal pharyngitis which results in rheumatic fever as the antibodies to the antigens in the streptococcal cell wall cross-react with the sarcolemma of the human heart.
Repeated attacks of S. pyogenes infection can result in damage to the heart valves.

Question 23

what is bronchitis

Answer 23

inflammation of the tracheobronchial tree

Question 24

what is acute bronchitis

Answer 24

 Usually occurs during the winter months

 Most often viral

Question 25

what is chronic bronchitis

Answer 25

 Productive cough on most days during in at least 3 months in each of 2 successive years
 Affects 10-25% of population
 Predisposing factors that all drive bronchitis include smoking, infection, air pollution and allergies
 Can be due to viral and bacterial agents

Question 26

what is bronchitis caused by 90% of the time

Answer 26

viruses e.g
rhinovirus
influenza
adenovirus

Question 27

what is bronchitis caused by 10% of the time

Answer 27

bacteria e.g
	B. pertusis (whooping cough) 
	M. pneumoniae 
	C. pneumoniae 
	H.  influenzae

Question 28

how can bronchitis be treated

Answer 28

Can be treated using decongestants, NSAIDs, antibiotics where appropriate

Question 29

why is mycobacterium tuberculosis so successful

Answer 29

due to the really lipidy outer cell wall which protects it

Question 30

how does mycobacterium tuberculosis happen

Answer 30

The organism enters the lungs through inhalation and the macrophages engulf if but they cannot process it so the microorganism reproduce inside them
A lesion begins to form (caseous necrosis) which is called a tubercle. The tubercle may go latent but it also has the potential to become systemic.

Question 31

what is treatment of TB

Answer 31

Treatment of it consists of triple therapy

The treatment is a long course (often 6 months)

Question 32

what are high risk factors in TB

Answer 32

 Close contact with known active TB case
 Residency in prison, nursing home, mental institution
 HIV infection
 Injection drug abuse
 Alcoholism
 Contact with persons from high prevalence TB countries (Africa, Asia, Latin America)

Question 33

what is pneumonia

Answer 33

Pneumonia is an inflammatory condition of the lung – especially affecting the microscopic air sacs (alveoli)

Question 34

what is pneumonia caused by

Answer 34

typically caused by infections, but multi-factorial (bacteria, viruses, funi, parasitse)

Question 35

what are the clinical features of pneumonia

Answer 35

 Sudden or insidious onset
 Fever, rigors, malaise
 Shortness of breath, rapid shallow breathing, cyanosis
 Cough producing sputum

Question 36

what are the causes of pneumonia

Answer 36

community acquired or hospital acquired

Question 37

what are the community acquired pneumonia microorganisms

Answer 37

 Streptococcus pneumoniae
 Viruses
 Mycoplasma pneumoniae
 Chlamydia pneumoniae

Question 38

what are the hospital acquired pneumonia microorganisms

Answer 38

 Staphylococcus aureus

 Gram negative bacteria’s

Question 39

why are those that are intubated more at risk of pneumonia

Answer 39

Oral health is often not looked after in hospitals and this is a source of infection

Question 40

whats the main causative agent in bacterial pneumonia

Answer 40

Streptococcus pneumoniae:

Question 41

why are encapsulated bacterias so good at escaping the immune system

Answer 41

The capsule covers antibody or C3b bound to the bacterial surface and it prevents contact between phagocyte receptor and opsonin – makes it difficult to phagocytose them
It also binds protein H (which is the target for C3b) for degradation and so this lessens the amount of C3b reaching bacterial surface and opsonizing the capsule

Question 42

how are bacterias clinically managed

Answer 42

through antibiotics
becta-lactames, erythromycin, quinolones
issues however w resistance

Question 43

how many different types of serotypes are there for vaccines

Answer 43

23

Question 44

what is done to make an efficacious vaccine

Answer 44

conjugation of polysaccharides and proteins

Question 45

how does toothbrushing help prevent hospital borne pneumonia

Answer 45

Toothbrushing can prevent hospital borne pneumonia
Patients who are intubated are more at risk as organisms can attach to the tube and this is an easy way for them to spread into the lungs and with the patients lying horizontal there is an aspiration pneumonia risk

Question 46

how do dentures lead to pneumonia risk

Answer 46

Dentures have the potential to harbor more microorganisms than the natural teeth if they are not cleaned and if patient wears them at night
Especially with patient lying flat there is an aspiration pneumonia risk