MRCP UK EXAMINATIONS

Detailed explanation-1: -It is now recognized that many common community-acquired and hospital-acquired pneumonias result from small-volume aspiration of more virulent pathogens from the oral cavity or nasopharynx, such as Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus, and gram-negative bacteria.

Detailed explanation-2: -The most common cause of community-acquired pneumonia (CAP) is S. pneumoniae, followed by Klebsiella pneumoniae, Haemophilus influenzae, and Pseudomonas aeruginosa. The most common causes of HCAP and HAP are MRSA (methicillin-resistant Staphylococcus aureus) and Pseudomonas aeruginosa.

Detailed explanation-3: -The typical bacteria which cause pneumonia are Streptococcus pneumoniae, Staphylococcus aureus, Group A Streptococcus, Klebsiella pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, anaerobes, and gram-negative organisms.

Detailed explanation-4: -Aspiration pneumonia occurs when you inhale food, drink, vomit or saliva into your lungs. Aspiration is more likely if something disturbs your normal gag reflex, such as a brain injury or swallowing problem, or excessive use of alcohol or drugs.

Detailed explanation-5: -The most common causative agent is Streptococcus pneumoniae, which is responsible for almost 50% of cases (Table 1); 5 other common causes are respiratory viruses (mainly influenza A) and the atypical bacteria Chlamydophila pneumoniae and Mycoplasma pneumoniae.