H. Influenza

Question 1

Specific growth requirements of H. Influenza x3

Answer 1

• “choc” or cooked blood agar
• aerobic
• nutritional factors ‘X’ (haematin) and ‘V’ (nicotinamide adenine dinucleotide)

Question 2

Pathogenesis of H. Influenza

Answer 2

bacteria attaches to epithelial cells and organism penetrates sub mucosa of nasopharynx, causing local inflammation and swelling, as it spreads from the initial site to infect bones, joints and CNS

Question 3

Transmission of H. Influenza

Answer 3

Infection from respiratory droplet/direct contact w patient

Question 4

What is the X nutritional factor?

Answer 4

Haematin

Question 5

What is the V nutritional factor?

Answer 5

Nicotinamide adenine dinucleotide (NAD)

Question 6

Which type of blood agar does H. Influenza grow better in? Why?

Answer 6

Cooked blood agar is better than normal blood agar bc the V factor is imprisoned in intact RBCs

Question 7

Significance of capsule of H. Influenza

Answer 7

Protects the bacteria from phagocytosis, reducing its susceptibility to the antibacterial role of serum

Question 8

What is the H. Influenza capsule made up of

Answer 8

Polyribosyl Ribotol phosphate

Question 9

Name 3 adhesins of H. Influenza

Answer 9

• P2
• fimbriae/Pili
• non-pilus adhesins

Question 10

Treatment of meningitis caused by H. Influenza

Answer 10

Antibiotics - cefotaxime and related cephalosporins e.g. Ceftriaxone

Question 11

Treatment of bronchitis caused by H. Influenza

Answer 11

Antibiotics: amoxicillin/erythromycin

Question 12

Treatment of pneumonia caused by H. Influenza

Answer 12

Antibiotics: flucloxacillin, Amoxycillin

Question 13

Characteristics of H. Influenza x3

Answer 13

• small
• gram neg bacilli
• non-motile