Infection: Surface |nfections, Immunodeficiency and Allergies Flashcards
Define a surface
What surfaces are there on a patient then?
Anything that acts as a barrier between a solid and anything else (solid, liquid or gas)
Skin- epithelia, hair, nails
Mucosal Surfaces
What are some examples of Commensals?
On the skin and Mucosa
Skin: Virus - Herpes simplex, Papilloma Bacteria - Staph aureus, Coagulase Neg. Staph, Gram Neg. Enterobacteriaceae Fungi - Yeast, Dermatophytes Parasites - Mites
Mucosa: Vagina- Lactobacilli Mouth- Viridans Strep., Neisseria Meningitis Nasopharynx- Neisseria Meningitis Nares- Strep aureus
How can Commensals cause problems?
Invasion- Pharyngitis by Strep pyogenes
Haematogenous- Viridans Strep endocarditis
Inoculation - Coagulase Staph prosthetic joint
Migration- UTI by E coli
Give examples of Prosthetic Surfaces?
IV Lines Catheters Joints Heart Valves Pacing Wires Grafts Ventriculo-peritoneal shunts
Pathogenesis of Surface Infections
Adherence
Biofilm formation
Invasion and Multiplication
Host Response- pyogenic and granulomatous
Treatment of Surface Infections?
Antibacterials
Removal of Prosthetic
Resection
Prevention of Surface Infections?
Prevent Contamination
Maintain Integrity
Prevent and Remove Colonising bacteria
What is an Allergy?
A hypersensitivity response of the body.
Hypersensitivity- an inappropriate/excessive immune response to a stimulus which results in harm
What can you get an allergic response from?
Exogenous substances- Pollen etc Insect Venom Dust Mites Chemicals - latex Food - milk, peanuts, shellfish
What mediates an allergic response?
IgE
Degranulation of mast cells and basophils
What are the consequences of Allergic responses?
Skin- Urticaria and Facial Oedema
Anaphylaxis- systemic activation of Mast Cells, describe…
How do you diagnose allergies?
History
Blood Test- for IgE and Mast Cell levels
Skin Prick Tests- Wheal and Flare
