Skin Infections Flashcards
1
Q
Where does body odor come from?
A
comes from microbes metabolizing and it’s waste products
2
Q
What microbiota does the skin have?
A
Malassezia (type of yeast), staph, micrococcus, diptheroids
3
Q
Folliculitis:
This is basically a “pimple” ( infection of ___ ___)
____: pimple at base of eyelid
Furnuncle:_____________
_____: Multiple furnuncles growing
- What is folliculitis caused by?
- How do you diagnose ?
A
This is basically a “pimple” ( infection of hair follicle)
sty: pimple at base of eyelid
Furnuncle: folliculitis spreads to infect surrounding tissue
Carbuncle : Multiple furnuncles growing
What is folliculitis caused by?
- caused by stapholo coccus
(Gram positive, grows in clusters)
- We diagnose by isolating the gram positive clusters in pus
4
Q
What 2 species of staph do we find on our skin?
-What are the differences between them?
A
Staph Aureus and Staph Epidermidis
- Staph Aureus is much more virulent. Has Protein A which inhibits optsonization, meaning the protein binds to antibodies so antibodies cant bind to phagocytes.
- S. Epidermidis 90% of our skin bacteria, although less harmful they are opportunistic
- S. Areus has the Exfolitative toxin and Epidermal Cell differentiation inhibitor (makes holes in blood vessels)
5
Q
Staph Scalded Skin Syndrome:
- caused by?
- Signs and symptoms?
- Transmission?
- Diagnosis?
*
A
- Caused by Staph Aureus (by use of exfoliative toxin), toxin gets into blood stream, spreads all over body (toxemia)
- Signs and symptoms: Red skin, wrinkled, form blisters, outter epidermis peels off in sheets. Since only the epidermis is affected (not the dermis) there will be no scaring
- Transmission: person to person
- this tends to be in children, death is rare since we are exposing lower layers of skin there is a chance for secondary bacterial infections
6
Q
Impetigo/Erysipelas:
- What causes each?
- What are the virulence factors of group A strep?
- How can this be a complication?
- transmission?
- Diagnosis?
A
- Impetigo can be caused by Staph arueus and/or Streptococcus pyogenes. Erysipelas is only caused by Strep pyogenes (Group A strep)
- Strep pyogenes or Group A strep virulence factors: M Protein (prevents phagocytosis), hylauronic acid capsule, pyrogenic toxins (fever inducing)
- can be a complication if this reaches blood stream and gets into kidneys: ACUTE GLOMERULONEPHRITIS
- Transmission is person to person or fomite
diagnosis is pressence of yellow vessicles
* kids get impetigo Eldery get erysipelas
7
Q
Necrotizing Fascitis:
- Caused by?
- this bacteria has what virulence factors?
- which 2 toxins allow for destruction of the tissue?
- Transmission?
- Diagnosis?
- Treatment?
A
- caused by Strep Pyogenes
- Its virulance factors includes:
- Streptokinase: dissolves blood clots
- Hyluroniase: dissolves hyluaronic acid (the glue that keeps cells together)
- dnase: breaks down DNA
- 1) Exotoxin A and 2) Streptolysin S, These enzymes facilitate tissue invasion
- Transmissions through breaks in the skin or person to person
- diagnosis is difficult early on because of its generic symptoms
- treatment: IV antibiotics, Surgical Debridement (clean and remove damaged tissue)
8
Q
Acne
- Caused by?
A
- caused by propioni bacteria. Tend to get when oily hair follicles are clogged up with oil
9
Q
Cat Scratch Disease:
- cause?
- signs and symptoms?
- transmission
A
- caused by gram negative bartonella henselae
- signs and symptoms: fever, malaise (tired icky feeling) local swelling
- transmission via cat bite/scratch, or blood sucking anthropods
10
Q
Pseudomonas:
- Where is this found?
- Signs and symptoms?
- What distinct feature (pigment) is in Pseudomonas?
- what type of patients usually get this disease?
- Why is pseudomonas problematic?
A
- Found EVERYWHERE: water, soil (likes flower vases)
- Signs and symptoms are fever, chills
- PYOCYANIN is the blue green pigment present in pseudomonas
- typically see this in burn patients, cystic fibrosis patients (get pseudomonas in their lungs)–> Burn patients need to do frequent debridement
- BIG problem: Pseudomonas is multi drug resistant (MDR), it is opportunistic and resistant to antibiotics
11
Q
Cutaneous Anthrax:
- caused by?
- characteristic?
- Treatment?
- prevention?
A
- Caused by Bacillus Anthracis (spore former)
- Characteristic is black eschar (painless leigons)
- treatment is antibiotics (Sypro)
- prevention is to control disease in livestock
12
Q
Gas Gangrene:
- Caused by?
- What type of enviornment does it grow in?
- signs and symptoms?
- vegatative cells produce ….
- traumatic event introduces….
- mortality rate exceeds ___%
- Diagnosis?
- Treatment?
A
Gas Gangrene
- Caused by clostridium perfringens (spore former)
- We will be seeing gas gangrene popping up when you have dying tissue (anaerobic enviornment). Clostridium perfringens has toxins which will kill surrounding tissue creating a bigger pocket of anaerobic enviornment (which also produces gas)
- signs and symptoms: death of muscle and connective tissue and pressence of gas bubble
- **vegatative cells produce 11 toxins
- traumatic even introduces spores into necrotic tissue
- mortality rate exceeds 40%
- diagnosis is dead tissue and gas pockets
- treatment: surgical debridement, **Antitoxin (binds up toxins so it can prevent spread)
13
Q
Small Pox:
- ____ based virus
- 1st human disease to be ____
- describe the phases of small pox
- Caused by…?
- transmission…?
- Treatment…?
A
Small Pox:
- RNA based virus
- 1st human disease to be eradicated
- the phases of small pox:
- macule: flat red rash
- papule: slightly raised, red reigon of skin
- vesicle: fluid filled pocket underneath raised skin
- pustule: when vesicle fills with pus
- crust: after pustule pops and dries (this still has the virus)
- scar
- Caused by: Small Pox Virus–> VARIOLA
- transmission: inhalation
- Treatment: Vaccine
14
Q
Herpes/Cold Sores:
- Caused by what?
- What is synctycia?
- transmission?
- treatment?
- How does the virus travel?
A
Herpes/Cold Sores:
- Caused by Human Herpes Virus (HHV) strains 1 and 2
- synctycia: virus gets into cell and causes cell to fuse to different cells so it looks like a big multinucleated cell –> this is how it stays hidden and evades the immune system.
- transmission: contact with mucous membranes of mouth/ genitals
- treatment: antiviral
- Virus can go dormant in different portions of the body and it can infect different parts of body depending on which nerve it travels down and lies in root ganglia
15
Q
Chicken Pox and Shingles:
- signs and symptoms?
- cause?
- pathogenesis?
- epidemiology?
- Treatment?
A
Chicken Pox and Shingles:
- signs and symptoms: ►Chicken Pox: highly contagious, characterized by lesions on the back and trunk, once you have the virus it is always in you, virus becomes latent within sensory nerves, once virus comes out of sensory nerves you get ►Shingles: occurs following reactivation of the virus, lesions localized to skin along an infected nerve
- The pathogen which causes both is: The Varicella-Zoster Virus (VZV)
- Pathogenisis: infection spreads from respiratory tract to the skin via blood and lymph
- Epidemiology: Risk of shingles increase with age, 20% of people who had chickenpox develop shingles
- Treatment is based on relief symptoms (EX: baking soda, Advil)
