Chapter 21: Diseases of skin and eyes Flashcards
What are the four types of skin lesions?
Vesicles, bullae, macules, and papules
“small fluid filled lesions”
Vesicles
“Larger fluid filled lesions > 1cm in diameter”
Bullae
“Flat lesions. Often reddish”
Macules
“raised lesions”
Papules
What are papules called when they contain pus?
Pustules
Do rashes and lesions indicate an infection of the skihn?
Not necessarily
The skin is a dry, cool environment that mostly grows gram __ bacteria
+
Name this genus and species. “Forms irregular clusters like grapes.”
Staphylococcus aureus
This genus and species is the most pathogenic of its genus and can survive for months on surfaces
Staphylococcus aureus
This genus and species is a permanent resident of 20% of nasal passages and 60% carry it occasionally
Staphylococcus aureus
What does the pigmentation of staphylococcus aureus do?
Protects it against the effects of sunlight
What do specific surface proteins of S. aureus do?
Allow for host protein attachment
S. aureus is positive for which -ase?
Coagulase
Which toxins does S. aureus produce?
enterotoxins
____ _____ secretes protein that blocks chemotaxis of neutrophils to the infection site
Staphylococcus aureus
Staphylococcus is resistant to ________ and survives well within phago-lysosomes
opsonization
S. aureus entering the body through a natural opening like a hair follicle causes _____
Folliculitis
Folliculitis often occurs as ____
pimples
The infected follicle of an eyelash is called a ____
Sty
A _____ is an abscess, localized region of pus surrounded by inflamed tissue.
Furuncle
Do antibiotics penetrate well into abscesses?
No
A _____ is a hard and round deep inflammation of tissue under the skin
Carbuncle
Carbuncle’s often exhibit symptoms of ____
fever
S. aureus entering through minor breaks in the skin can cause _____
Impetigo
How does impetigo heal?
Without treatment or scarring
Impetigo is a ______ and common form
nonbullous
What is the bullous impetigo called?
Scalded skin syndrome
What is scalded skin syndrome caused by?
Staphylococcus toxins
Exfoliative toxin A is _____ and toxin b is in _____ ____
Localized; distant sites
What does scalded skin syndrome cause?
Separation of skin layers
What pathogen causes toxic shock syndrome?
S. aureus
Describe TSS.
Life threatening, fever, vomiting, sunburn like rash, organ failure.
What mainly caused TSS?
Tampons being left in too long
Staphylococcus overgrowth from leaving tampons in too long causes which toxin to form?
Toxic shock syndrome toxin 1 (TSST-1). Forms at growth site and circulates in blood stream
What are the symptoms of TSS a result of?
The result of super antigenic properties of the toxin.
Streptococcus pyogenes usually grows in ____
chains
As streptococci grow, what happens?
Toxins and enzymes are secreted. Varies with species.
Which type of toxins does S. pyogenes produce?
Hemolysins
What three hemolysins are listed on the powerpoint?
Alpha-hemolytic, Beta-hemolytic, and gamma hemolytic.
Hemolysin toxins of S. pyogenes are differentiated into…
into serological groups A-T antigenic carbohydrates in cell walls)
Group A betaB strep (GAS) is the most common or least common of human pathogens?
Most common
GAS produces _______, which lyse red blood cells and are toxic to neutrophyils
Streptolysins
What are the three substances of GAS that promote rapid spread of infection by liquefying pus
Streptokinases, Hyaluronidase, and Deoxyribonucleases
How many immunological types of GAS are there?
80
The 80 different immunological types of GAS, in which some strains contain M protein, prevents activation of _____ and evades phagocytosis
Complement
The different immunological types of GAS aids in adherence to what?
Mucous membranes
GAS has a capsule of _____ acid in which few antibodies against the capsule are produced
Hyaluronic acid
GAS can cause _____ (just like S. aureus can)
impetigo
Impetigo affects the superficial _____ layer of skin
keratin
______ is infection of the dermal layer of the skin
Erysipelas
Describe erysipelas
Dermal layer infection. Reddish patches with raised margins. Can progress to local tissue and enter the blood stream.
Which pathogen causes necrotizing fascilitis?
Group A beta strep (GAS)
How many cases of necrotizing fascilitis occur yearly in US?
1,000
What is the problem with treating NF?
It can destroy tissue as rapidly as the surgeon is removing it
Why are broad spectrum antibiotics used to treat NF?
Multiple pathogens might be present
Pyrogenic toxins produced by GAS with necrotizing fascilitis act as ______
superantigens
Streptococcus ______ is also known as Group B beta strep (GBS)
agalatiae
Colonization of GBS is _____ and ______
asymptomatic and intermittent
Colonization of GBS is < __% of women vaginally and < ___% of adults intestinally
25% and 30%
Colonization of GBS occurs in the intestines in less than ___ percent of adults
30%
Colonization of GBS occurs vaginally in less than ___ percent of women
25%
Infection of GBS occurs in newborn babies and which adults?
Pregnant women, elderly, and immunosuppressed patients
Which genus and species causes acne?
Propionibacterium acnes (Cutibacterium)
What are the three types of acne lesions?
Comedonal, Inflammatory, and nodular cystic
Nodular cystic acne is mild, mod, or severe?
severe
Which acne is moderate
Inflammatory
Which acne is mild
Comedonal
Black heads are called _____
comedone
White heads are called ____
comedos
Inflammatory acne is treated with topical agents such as ______ acid
Salicyclic acid
Inflammatory acne is considered a…
bacterial infection
What is P. acne’s nutritional requirement?
Requires glycerol in sebum
Metabolizing sebum forms ____ _____ acids
free fatty
Metabolizing sebum forms free fatty acids. This causes what two actions?
Inflammatory response and the neutrophils secrete enzymes
Which topical agents are not effective against inflammatory acne?
Clindamycin and erythromycin
What are the clinical signs of Nodular cystic acne?
Inflamed lesions filled with pus deep within in the skin. Leaves scars
Tx for Nodular acne?
Roaccutane, formerly known as accutane.
Side effects of Isotretinoin? (roaccutane)
Teratogenic, IBS, ulcerative colitis
Which species and genus has gram - rods?
Pseudomonas aeruginosa
____ ____ is widespread in soil and water
P. aeruginosa
What random place is P. aeruginosa found?
Soap films and cap liner adhesives for containers
_____ _____ is an opportunistic pathogen
P. aeruginosa
What can cause you to catch Pseudomonas dermatitis?
Swimming pools, saunas, hot tubs
What causes swimmers ear?
P. aeruginosa
What are the five viruses of the skin given in lecture?
- Rubeola
- Rubella
- Varicella-Zoster virus
- small pox
- herpes simplex
Rubeola is also known as ____
measles
What am I?
- extremely contagious viral disease
- spread by respiratory route
- incubation period of 10-12 days
- dangerous disease…pneumonia, secondary bacterial infections, and encephalitis
Rubeola (paramyxoviridae) measles
Rubella is also known as _____
German measles
What am I?
- Milder than measles, often goes undetected
- transmission by resp. route
- incubation of 2-3 weeks
- congenital rubella syndrome: maternal infection during first trimester
Rubella….German measles
With congenital rubella syndrome, what percentage results in serious fetal damage?
35%
What are the common effects of congenital rubella syndrome?
Deaf, heart defects, autism, and death
What year was the rubella vaccine introduced?
1969
With what vaccine are individuals 90% protected for at least 15 years?
Rubella..German measles
