Skin and Soft Tissue Infections Flashcards
What are some local symptoms of inflammation?
Pain, swelling, redness, temperature, loss of function
What are some systemic symptoms of inflammation?
Fever, sweats, rigors
Where is the most common site for soft tissue skin infection?
Lower leg
What is erysipelas?
An intradermal infection caused by Group A, beta haemolytic strep. Usually S.pyogenes +/- S.aureus
What is cellulitis?
A subcutaneous infection, caused by the same bacteria as erysipelas
When are other causative organisms common?
Drug users, immunocompromised hosts
What does Impetigo look like?
Red, weeping lesions which have begun to crust
What should you do when impetigo is diagnosed?
Treat empirically with oral flucloxacillin and take a black charcoal swab
Describe a catalase test
Smear colonies on hydrogen peroxide, if bubbles of oxygen form, the test is positive
What bacteria is the causative organism if investigations show one type of organism on blood agar, colonies are yellow and don’t haemolyse, gram test shows gram positive cocci in clusters, catalase and coagulase tests are positive?
S.aureus
Describe a typical case of cellulitis
Non-specifically unwell and no appetite, calf and foot red, hot, painful and swollen, fever
How does cellulitis occur?
Bacteria from skin surface breach the epidermis and invade subcutaneous tissues
What bacteria is the causative organism if investigations show gram positive cocci in chains that are white beta haemolysing colonies on blood agar and are positive for Lancefield group A?
S.pyogenes or another group A streptococci
What is the first line antimicrobial for S.pyogenes/group A streptococci?
Penicillin, benzyl penicillin
Describe what signs/symptoms you might see in someone with an infected IV cannula site
Raised urea and creatinine, red arm, confusion
