bacterial infections of URT Flashcards
(33 cards)
normal flora of nares
S epidermidis
S aureus
Corynebacterium spp.
normal flora of nasopharynx
Streptococcus: Viridans group (S mutans, mitis, milleri, salivarius) Moraxella catarrhalis Bacteroids S pneumoniae H influenzae N meningitides
M protein
causes degradation of C3b (opsonin) –> antiphagocytic
essential for virulence
Streptococcal pyrogenic exotoxins (SPEs)
super antigens responsible for scarlet fever, toxic shock syndrome, and necrotizing fasciitis
only scarlet fever preceded by strep throat symptoms
nine proteins
cause fever, rash, T cell proliferation, B cell suppression
is scarlet fever or acute rheumatic fever caused by inflammatory response?
acute rheumatic fever
do SPEs cause scarlet fever or acute rheumatic fever?
scarlet fever
will cultures for acute rheumatic fever show S pyogenes?
no, onset ~3 weeks after initial infection
host has fought off infection
disease caused by inflammatory response to infection
diseases associated with S pyogenes
Streptococcal pharyngitis Scarlet fever Acute rheumatic fever Streptococcal toxic shock syndrome Post-streptococcal infection sequelae (acute glomerulonephritis)
diagnosis of Strep pharyngitis
culture of posterior pharynx and tonsils
blood agar plates –> beta hemolysis
treatment of Strep pharyngitis
10 day course of penicillin or erythromycin
symptoms of scarlet fever
desquamation of hands, redness of skin, white coating on tongue
symptoms of acute rheumatic fever
fever, joint pain, chest pain, rash, nodules, jerky movements
acute glomerulonephritis
post-streptococcal infection sequelae
1-4 weeks after strep pharyngitis, or 3-6 weeks after skin infection
seen in children
deposition of antigen-antibody complexes in glomeruli –> inhibition of filtration
symptoms: edema, HTN, hematuria, proteinuria, decreased serum complement levels
epidemiology of strep pharyngitis
respiratory droplets
if untreated, can be carried for weeks
anal carriers –> nosocomial infection
can spread by food contaminated by carriers
diagnosis of strep pharyngitis
culture –> blood agar –> beta hemolysis
treatment of strep pharyngitis
10 days penicillin or erythromycin
symptoms of diphtheria
mild sore throat, slight fever, high fatigue, dramatic neck swelling, whitish gray membrane to tonsils/throat/nasal cavity
organism that causes diphtheria
Corynebacterium diphtheriae
Corynebacterium diphtheriae
gram + rod
non spore forming
Chinese letters
treatment of diphtheria
a
symptoms of pinkeye
tears, conjunctival redness, photophobia, EYELID SWELLING, PUS
organisms that cause pinkeye
Haemophilus influenzae Streptococcus pneumoniae Moraxella lacunata Enterobacteria Neisseria gonorrhoeae
pathogenesis of pinkeye
airborne respiratory droplets or rubbed in eye from contaminated hands
organisms resist lysozyme
symptoms induced by inflammatory response to organisms
treatment of pinkeye
gentamicin or ciprofloxacin drops
