Chronic Disease Flashcards
How do chronic diseases link to infections?
They can predispose to specific infections:
- Can change structure/function of tissue–> effect on interaction between patient and microorganism
- Altered presence of micro-organisms- consequences of treatment
What is Cystic Fibrosis?
- Autosomal recessive condition
- Defect- transmembrane conductance regulator (CTFR) gene- in exocrine glands- codes for cAMP regulated chloride channel
- Reduces secretion of Cl-
- More water reabsorbed
What complications does cystic fibrosis cause?
- Lungs- colonisation and infection w./ various organisms
- Pancreas- pancreatitis, diabetes, malabsorption
- Intestines- thick secretions- bowel obstructions in newborns
- Liver- cirrhosis
- Reproductive system- infertility
- Sinus-infections
Why are patients more suceptible to infections?
Compromised innate immune system:
- Mucus=dehydrated + thick
- Clearance of organisms= impaired
=Reduced ciliary action
=Airway remodelling
Name some infections that CF patients are particulary susceptible to.
- H influenzae
- Staph aureus
- Pseudomonas aeruginosa
- Burkholderia cepacia
- Atypical Myobacteria, Candida albicans, Aspergillus fumigatus
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Why are CF patients particullary susceptible to Pseudomonas aeruginosa infections?
CF causes biofilms as:
- Damages local epithelium- cycle of inflammation
What steps can be taken to prevent respiratory infections developing in cystic fibrosis patients?
- Encourage mucus clearance (chest physiotherapy, nebulisers, bronchodilators)
- Steroids- reduce inflammation
- Prophylactic antibiotics- prevent colonisation
- Good hand hygiene
- Good nutrition
Why are patients with diabtetes more susceptible to infections?
- Microvascular and macrovascular disease–> poor tissue perfusion+increased infection risk
- Neuropathy- diminished sensation- unnoticed skin ulcers/cuts (breach innate immunity
- Hyperglycaemia- impairs humoral immunity (ie neutrophil and lymphocytes functions)
What infections are diabetes patients particularly susceptible to?
- Cellulitis
- UTIs
- Malignant otitis externa
- Respiratory infections
Why is cellulitis commonly found in diabetic patients?
Hyperglycaemia, imparied sensation, reduced perfusion
If a patient with diabetes presents with a foot ulcer, what actions should be taken?
- Identify infection-swab for culture
- Assess severity of infection:
- Blood markers (FBC, CRP)
- Foot X-ray (osteomyelitis)
- Renal function (U&Es)
- Check Glycaemic control (BM/HbA1c)
How should diabetes patients be manged with relation to developing cellulitis? (5)
- Treat infection if present
- Maintain good glycaemic control
- Regular foot checks
- Good foot care
- Reduced CVS risk factors
Why are UTIs common in diabetic patients?
- Diabetic neuropathy- defects in bladder emptying (stasis)
- Glycosuria- increase bacterial infections
(Causative organisms: E coli, pseudomonas aeruginosa)
What investigations should be carried out for UTIs in diabetic patients?
Urinanalysis:
- Glycosuria
- Nitrites+leucocytes
Sepsis screen
FBC, CRP etc
What is malignant otitis externa?
External ear infection
Spreads from EXTERNAL AUDITORY CANAL to adjacent soft tissue/bone
Caused by pseudomonas aeruginosa
How does a patient with malignant otitis externa present?
Severe ear pain
Why are respiratory infections more likely to occur in diabetic patients?
Hyperglycaemia: impair neutrophil function
Can have altered perfusion
Name some examples of respiratory infections which can be acquired particularly in Diabetic patients.
- Streptococcus pneumoniae
- Haemophilus influenzae
- Staphylococcus aureus
What causes COPD?
- Chronic inflammatory response to inhaled irritants
- Primarily mediated by neutrophils and macrophages
Why are patients with COPD more susceptible to infections?
- Local overeactivity- inflammation damages airways
- Emphysema-breakdown lung tissue
- Obstructive bronchitis, damage to cilia
- Increased mucus production
What infections are patients with COPD more susceptible to?
- Pneumonia
- H.influenzae
- Ps. aeruginosa
