med micro microbial diseases of the skin and eyes

what 2 things in the skin contain nutrients?

perspiration and sebum

what inhibits microbes in the skin?

salt

what hydrolyzes peptidoglycan in the skin?

lysozyme

what inhibits some pathogens in the skin?

fatty acids

what are antimicrobial peptides in the skin?

defensins

mucous membrane

line body cavities; epithelial cells are attached to an extracellular matrix

in mucous membranes cells secrete. __________

mucous

mucous is often basic or acidic

acidic

1 multiple choice option

in mucous membranes, some cells have cilia t/f

true

1 multiple choice option

in the eyes, tears contain _________

lysozyme

what is a normal, gram +, salt tolerant bacteria found on the skin?

Staphylococci spp.

normal microbiota of the skin grow on ________

olis

what is an aerobe found on the surface of the skin?

Corynebacterium xerosis (G+)

what is an anaerobe found in hair follicles?

Propionibacterium acnes (G+)

what are normal yeasts found on the skin?

Malassezia furfur and Candida albicans

what are the 4 types of skin lesions?

vesicle, bulla, macule, pustule

vesicle

small, fluid-filled raised spot on the skin; blister

bulla

large blister containing watery fluid

macule

flat, colored spot on the skin (freckle)

pustule

raised spot on the skin containing pus

exanthem

skin rash

enanthem

mucous membrane rash

what are 2 staphylococcal skin infections?

Staphylococcus epidermidis and Staphylococcus aureus

Staphylococcus epidermidis

opportunistic, gram + cooci, coagulase negative

Staphylococcus aureus

gram + cocci, coagulase positive, multi drug resistant

Staphylococcus aureus resists ___________

opsonization

Staphylococcus aureus survives in ____________

phagolysosome

leukocidin

kills leukocytes

coagulase

coagulates plasma

hyaluronidase

digests extracellular matrix

staphylokinase

digests blood clots

exfoliative toxin

digests epithelium

superantigen

drives anaphylactic shock

folliculitis

infections of the hair follicles

sty

folliculitis of an eyelash

furuncle

abscess; pus surrounded by inflamed tissue

carbuncle

inflammation of tissue under the skin

what involves a single follicle and what involves multiple follicles?

single: furuncle

multiple: carbuncle

impetigo

crusting (nonbullous) sores, spread by autoinoculation

Staphylococcus aureus intoxication causes what 2 syndromes?

toxic shock syndrome and scaled skin syndrome

toxic shock syndrome (TSS)

due to superantigen toxin (TSS toxin)

scaled skin syndrome (SSS)

bullous lesions; impetigo of the newborn; due to exfoliative toxins A and B

scaled skin syndrome (SSS) % mortality

50%

Streptococcus pyogenes

beta hemolytic

hemolysins

digest RBCs

hyaluronidase

digest ECM

streptolysins

digest RBCs

M proteins

blocks opsonization and phagocytosis

erysipelas

blisters or swollen lesions

necrotizing fasciitis

flesh eating disease

necrotizing fasciitis caused by

superantigen exotoxin

M protein = _______ factor in ?

virulence; S. pyogenes

lesions of erysipelas caused by B-hemolystic streptococcal toxins

lesions of facial erysipelas caused by hemolytic streptococcal toxins

necrotizing fasciitis due to Streptococcus pyogenes

necrotizing fasciitis due to Streptococcus pyogenes

infections by Pseudomonas aeruginosa

pseudomonas dermatitis, otitis externa, post burn infections, common nosocomial agent

Pseudomonas aeruginosa

gram - aerobic rod; pyocyanin; opportunisitc

pyocyanin

produces a blue-green pus

Pseudomonas dermatitis

2 week rash

otitis externa

swimmers ear; inflammation of the outer ear

intoxication by Clostridium perfringens

gas gangrene, phospholipase exotoxin, requires early treatment otherwise fatal

Clostridium perfringens

gram + anaerobe, can form endospores, commonly found in soil

gas gangrene

myonecrosis

phospholipase exotoxin

alpha toxin

what is a treatment for Clostridium perfringens?

hyperbaric oxygen therapy

"trench foot" from Clostridium perfringens

necrotic blisters from Clostridium perfringens

buruli ulcer

caused by Mycobacterium ulcerans; deep, damaging; exceeds incidence of leprosy

what are the 3 classifications of acne?

comedonal (mild), inflammatory (moderate), nodular cystic (severe)

comedonal acne

mild; sebum channels are blocked with shed cells

comedonal acne treatment

salicylic acid preparations and retinoids

inflammatory acne

Propionibacterium acnes

Propionibacterium acnes

gram +, anaerobic rod

inflammatory acne treatment

preventing sebum formation (isotretinoin), antibiotics, benzoyl peroxide to loosen clogged follicles, visible (blue) light (kills P. acnes)

isotretinoin

prevents sebum formation but teratogen

nodular cystic acne

severe

nodular cystic acne treatment

isotretinoin

treatment for bacterial conjunctivitis (possibly bonus cause Gary had it)

ofloxacin and cephalosporin

warts

papillomaviruses

treatment for papillomaviruses

removal and imiquimod

what are 3 ways to remove warts?

cryotherapy, electrodesiccation, salicyclic acid

cryotherapy

cold treatment

electrodesiccation

tissue is destroyed by burning with an electric spark

imiquimod

stimulates interferon production

interferon signaling drives _________ ________ expression

antiviral peptide

smallpox

variola

variola major mortality rate

20%

variola minor mortality rate

less than 1%

smallpox was eradicated t/f

true (1979)

1 multiple choice option

a single case of smallpox is considered a health emergency why?

very communicable

who discovered the smallpox vaccine and with what?

Edwen Jenner; discovered that vaccina virus or cowpox has a similar structure to smallpox and was not deadly to humans (discovered this when milk maids were not getting sick/were not dying)

centrifugal lesions

more on periphery, less in body center

centripetal lesions

moves toward the center

smallpox lesions

extremely itchy which can cause secondary infection of other microbes getting in (like MRSA under fingernails)

smallpox centrifugal or centripetal lesions?

centrifugal

chickenpox centrifugal or centripetal lesions?

centripetal

varicella-zoster virus

chicken pox; humam herpesvirus 3

how is chickenpox transmitted?

by respiratory route