Chapter 21 Flashcards
When does a vesicle become a bulla?
When it grows larger than 1cm in diameter.
What is a carbuncle? What is a furuncle?
Carbuncle: Hard round deep inflammation of tissue under the skin
Furuncle: Abscess, localized region of pus surrounded by inflamed tissue
Which Gram + bacterium causes inflammatory acne?
Propionibacterium
What are comedos and comedones?
- Comedos: whiteheads
- Comedones: blackheads
What is a virulence factor?
A virulence factor is how dangerous the microbe is. Factors that improve virulence are: pigmentation, coagulase, toxins
What are the name of the toxins that cause scalded skin syndrome?
Exfoliative toxin A and Exfoliative toxin B
Which two bacteria cause impetigo?
- Staphylococcus aureus
- Streptococcus pyogenes
How does TSST-1 affect the body?
Toxic Shock Syndrome Toxin 1 (TSST-1) causes toxic shock syndrome, leading to fever, vomiting, rash, and organ failure.
Which organic acid produced by fermenting bacteria causes inflammation in the
skin
Free fatty acids.
Which type of acne is the most severe?
Nodular cystic
What is the basis for subdividing Streptococcus into smaller divisions? You
should be able to recognize the proper Greek letters
By how much hemolysin they produce.
Why are the Group A β Strep relevant?
Because they are the most common human pathogens
In what groups of people does Group B β Strep mainly cause disease?
Mainly causes disease in newborn babies, pregnant women, the elderly, and immunosuppressed patients.
What are the toxins that contribute to necrotizing fasciitis?
Pyrogenic toxins produced by Streptococcus pyogenes acting as superantigens.
Which bacterium is associated with water and can cause problems with
swimmers or bathers?
Pseudomonas aeruginosa
What specific ear infection is caused by this water-based bacterium?
Swimmer’s ear
How are the different forms of measles spread?
Spread through the respiratory system
What is the approximation incubation period of measles?
Incubation period of 10-12 days
How does the chicken pox rash change over time?
It starts as vesicles, fills with pus, ruptures, and forms a scab
Can an adult with shingles give chicken pox to a child?
Yes, if the child is not vaccinated, exposure to shingles can lead to chickenpox.
Are the viruses present in the body continually between chicken pox and
shingles?
Yes, the Varicella-Zoster Virus remains latent in the body after chickenpox and can reactivate to cause shingles.
Which form of herpes simplex most commonly manifests near the mouth?
Herpes simplex virus-1 (HSV-1)
How is oral herpes usually spread?
Transmitted orally or through the respiratory route.
Which type of herpes simplex is much more common?
HSV-1
Where does herpes simplex type-2 show lesions?
Genital herpes
How do superficial mycoses obtain nutrients?
Superficial mycoses obtain nutrients by metabolizing sebum, forming free fatty acids.
What are some genera of fungi that can infect the skin?
Trichophyton, Microsporum, Epidermophyton.
What are the names of the kinds of ringworms based on their location?
Tinea capitis (scalp), Tinea cruris (groin), Tinea pedis (foot), Tinea unguium (nails).
What are the two skin parasites discussed in lecture?
Sarcoptes scabiei (scabies) and Pediculus humanus (lice)
How are skin parasites usually transmitted to a new host?
Through intimate contact, including sexual contact
What are the two subspecies of body lice?
Pediculus humanus capitis (head louse) and Pediculus humanus corporis (body louse)
