Infection 8 - Infections in Chronic Health Conditions

Question 1

What types of infections are diabetics prone to?

Answer 1

• ENT infections
• Rhinocerebral mucomyosis
• UTIs
• Skin + Soft Tissue infections

Question 2

How does malignant/necrotising otitis externa present?

Answer 2

• severe ear pain

- otorrhoea

Question 3

Which bacteria is usually the causative organism of malignant/necrotising otitis externa?

Answer 3

Pseudomonas aeruginosa

Question 4

What type of patients are particularly at risk of developing malignant/necrotising otitis externa?

Answer 4

Elderly diabetic patients

Question 5

What is Rhinocerebral mucormycosis?

Answer 5

Fungal infection of the nose and paranasal sinuses, leading to soft tissue necrosis and bony erosion

Question 6

What type of patients are particularly at risk of developing Rhinocerebral mucormycosis?

Answer 6

Diabetics (particularly if in DKA)

Question 7

Why do diabetics have a higher risk of developing UTI’s?

Answer 7

• Neurogenic bladder due to neuropathy = urine stasis

Question 8

Which bacteria are often the causative organisms of UTIs in diabetic patients?

Answer 8

• Enterobacteriaceae (ie E.coli)

- Pseudomonas aeruginosa

Question 9

What types of skin and soft tissue infections are diabetics prone to developing?

Answer 9

• Foot ulcers
• Cellulitis
• Folliculitis
• Necrotising fasciitis

Question 10

What type of bacteria usually cause folliculitis in diabetics?

Answer 10

Staph. aureus

Question 11

What type of bacteria usually cause cellulitis in diabetics?

Answer 11

• Staph. aureus

- Group A beta-haemolytic streptococcus

Question 12

What type of bacteria usually cause foot ulcers and necrotising fasciitis in diabetics?

Answer 12

• Staph. aureus
• Group A beta-haemolytic streptococcus
• Enterobacteriaceae
• Other anaerobes

Question 13

Why do diabetics rarely respond well to surgery?

Answer 13

Vascular disease impairs healing

Question 14

Cystic fibrosis follows which inheritance pattern?

Answer 14

Autosomal recessive

Question 15

Whats the most common mutation causing cystic fibrosis?

Answer 15

Deletion of Phenylalanine at position 508

Question 16

Which molecule regulates the CFTR Cl- channel?

Answer 16

cAMP

Question 17

Name 4 part of the body that is affected by cystic fibrosis:

Answer 17

1) Respiratory system - repeated inflammation + infection
2) Pancreas - blocks ducts, less enzymes released
3) Urogenital system - absence of vas deferens in men
4) GI tract - rectal prolapse, constipation, malabsorption

Question 18

What bacteria most commonly cause lung infections in young children with cystic fibrosis?

Answer 18

• H. influenzae

- Staph. aureus

Question 19

Which types of bacteria commonly cause lung infections in older children/early adults with cystic fibrosis?

Answer 19

• Ps. aeruginosa

- Bulkholderia cepacia

Question 20

Why do cystic fibrosis sufferers have a higher mortality rate from a Ps aeruginosa infection?

Answer 20

• Defective ingestion of bacteria by epithelial cells
• Abnormal composition of mucous = impaired function of antimicrobial peptides
• Abnormal innate immune system
• Tend to be colonised by Mucoid Ps = worsened effects

Question 21

What microorganisms typically cause infections in adults with cystic fibrosis?

Answer 21

• Atypical mycobacteria (not TB)
• C. albicans
• Asp. fumigatus

Question 22

How can cystic fibrosis patients encourage mucous clearance to reduce infection risk?

Answer 22

• Chest physiotherapy
• Hypertonic saline nebuliser
• Mucolytics
• Bronchodilators
• Steroids

Question 23

What type of bacteria commonly cause acute COPD exacerbations?

Answer 23

• H. influenzae
• M. catarrhalis
• S. pneumoniae
• Ps. aeruginosa
• E.coli

Question 24

What type of viruses commonly cause acute COPD exacerbations?

Answer 24

• Respiratory syncytial virus
• Rhinovirus
• Influenza A
• Parainfluenza
• Coronavirus
• Adenovirus
• Human metapneumovirus