Infection Session 5

Why does the rhinovirus remain within the nasal cavity instead of travelling down to the lower respiratory tract?

• Change in pH

• Change in temperature 

• Change in diameter 

• Change in surface area 

Answer explanation

The lower respiratory tract has a higher temperature than the nasal cavity. The rhinovirus can exist only at 33 degrees C.

Which of these are NOT a part of the respiratory tract’s natural defences?

• Ciliary escalator 

• Immunoglobulins in the mucus 

• Bronchial beat 

• Alveolar macrophages 

Answer explanation

The cilia beat mucous containing trapped micro-organisms up the pharynx 

Hospital patients are particularly vulnerable to gram _ bacteria

Answer explanation

E.coli, pseudomonas, klebsiella, staph.

More serious, often require IV antibiotics. 

Which of these micro-organisms are commonly associated with contaminated water?

• legionella pnuemophila 

• Strep pneumonae 

• Klebsiella

• Staphylococcus aureus 

Answer explanation

Legionella, a gram negative bacteria found in contaminated water. It is not passed on from person to person - patients can often be asymptomatic

Which one is NOT a main risk factor for developing pneumonia? 

• very young age 

• Old age 

• Hypertension 

• Diabetes

Answer explanation

Chronic cardiac conditions such as ischaemic heart disease or congestive cardiac failure could increase risk of infection given poor physiological reserve, although hypertension on its own is not a known risk factor. 

Babies and young children are at risk of developing viral infections

 What is the pattern of microbial colonisation present in the image?

• Atypical

• Lobar

• Intersistial

• Broncho-pneumonia

Answer explanation

 Patchy distribution commonly seen in aspiration or intubation pneumonia’s (staph, e-coli, pseudomonas).

Atypical pneumonia’s are more commonly seen near the hilum and diffuse. Interstitial is mainly in the alveolar wall.

Lobar is a typical CAP presentation. 

Mr A is a 89 year old male who presents with a cough, shortness of breath, fever and increased confusion.

His blood pressure is 130/80, respiratory rate 25, oxygen saturations are 89% on room air.

Blood gas shows a type 1 respiratory failure with a raised urea of 7.2 mmol/litre.

What is Mr A’s CURB 65 score?

• 1

• 2

• 3

• 4

Answer explanation

What are you going to do for Mr A?

• Discharge with oral antibiotics 

• Send patient home following oxygen therapy after some stern safety netting 

• Admit for intravenous antibiotics and consider discussing with intensive care

• Admit straight to intensive care for intubation 

Answer explanation

mechanical ventilation should only be considered in severe respiratory distress:

1) hypoxia

2) hypercarbia

Hypoventilation