skin and wound infection Flashcards
(39 cards)
Lyme disease is the most common
vector-borne disease
transmitted via
a bite from an infected black-legged Ixodes tick
gram + or -
-
spirochete
thin, tightly coiled, helically shaped bacteria
- have an outer membrane contained LPS
-posses endoflagella
main reservoir
white footed mouse
bacteria that causes Lyme disease
borrelia burgdorferi
pathogenesis of Lyme disease
tick feeds on animal
grows to maturity (nymph)
feeds on human (accidental host)
stage 1 Lyme disease
erythema migraines
- bulls eye rash
- flu-like symptoms
stage 2 Lyme disease
injury to nervous and cardiac systems
-dizzy spells, fainting, difficulty concentrating
- paralysis of face
stage 3 Lyme disease
immune response damages host tissue
- arthritis with severe joint pain and swelling (knees)
- sometimes meningitis or encephalitis
treatment and prevention of lyme disease
antibiotics treat first stage
- no available vaccine for humans
tinea corporis
ringworm
-scaly skin in the center surrounded by a raised red margin that occur on smooth skin
tinea capitis
ringworm
- severe cases affect scalp and hair-bearing regions of head causing patchy areas of hair loss
dermatophytes that cause ringworm, athlete’s foot, and toenail fungus
epidermophyton, microsporum, and trichophyton
tinea pedis
athletes foot
- scaly itchy rash between toes
tinea unguium
nail fungus
- more common in elderly
-chronic infection of the nails
- infected nails of the hands and feet become thickened, yellow, and brittle
clostridium tetani
endospore-former
-gram positive rods
- obligate anaerobe
enter the body and germinate in damaged/necrotic tissue
symptoms of tetanus (C. tetani)
prolonged contraction of muscles
tetanospasmin
A type of A-B exotoxin
- taken up by inhibitory neurons where it prevents release of inhibitory neurotransmitters (GABA)
- GABA cannot end contraction
tetany
muscles receive constant stimuli and contract uncontrollably
-death usually results from respiratory failure
treatment of tetanus
muscle relaxants, supportive care necessary
- human tetanus immune globulin injection
- antibodies bind to free toxin molecules, provide passive immunity
prevention of tetanus
DTaP vaccine
- contains toxoid (inactivated tetannospasmin)
-requires boosters
tetanus is the only non-contagious disease we routinely vaccinate against
clostridium perfringens causes
gas gangrene
gas gangrene signs and symptoms
severe pain
thin bloody or brownish exudate leaks from wound
gas bubble in tissue
overlying skin stretched tight and mottled with black