Bacteria - Diseases Flashcards
Food poisoning <6hr
S. aureus -> enterotoxin -> intoxication
nausea, vomiting, diarrhea
Osteomyelitis
S. aureus ~50%
bacterial infection of bone
Septic Arthritis
S. aureus (w/ N. gonorrhoeae) Most common
bacterial infect of joint
Endocarditis
S. aureus ~1/3
infect of heart, usually valves. S aureus very destructive, progresses fast
S. aureus pneumonia
rare, very destructive
Pharyngitis
S. pyogenes (Type A Strep)
Outcomes: recover (3-5 days), scarlet fever, supperative sequelae (otidis media, sinusitis), rheumatic fever, acute glomerulonephritis
Scarlet Fever
Hypersensitivity to S. pyogenes pyrogenic toxin
1-2 days after pharyngitis
Sx: Diffuse “sandpaper” rash (esp at skin folds, spares palms, soles, face); desquamates; strawberry tongue
Acute Rheumatic Fever
Cause unknown
1-4 weeks after S. pyogenes infection
Prevention: antibiotic tx
Sx: migrating polyarthritis, mitral/aortic valve damage, chorea (involuntary movement), painless subcutaneous nodules, erythema marginatum, “Aschoff nodules”
Tx: corticosteroids, aspirin, antibiotics (to prevent recurrence)
Outcome: resolves in weeks-months; long-term heart valve damage
Poststreptococcal Acute Glomerulonephritis
Type 3 hypersensitivity; Immunocomplexes (IgG + complement)
1-3 weeks after S. pyogenes infection
Not prevented by antibiotic tx
Sx: Edema, hypertension, rusty colored urine
Skin & Soft Tissue Infections
Staphlococcus (S. aureus, coagulase-negative)
S. pyogenes (group A strep)
SSSS (Ritter’s disease)
S. aureus - exfoliative toxins
Desquamation over most of body
Children who lack antibody
Bullous impetigo
S. aureus - exfoliative toxins
Local desquamation -> large blisters (bullae)
Folliculitis, furuncles, carbuncles
S. aureus (>90%)
Pyogenic infection of hair follicles
Impetigo
S. aureus or S. pyogenes
Infection of epidermis
Oozing lesions, honey-colored crust
Cellulitis
S. aureus or S. pyogenes
Infection of subcutaneous tissue
Erysipelas
S. pyogenes (>90%)
Dermis, Dermal lymphatic infection
Painful red area, sharply demarcated, raised border; usually legs or face
Necrotizing fasciitis
Type I: multimicrobial; obligate anaerobes, facultative anaerobes (S. pyogenes, S. aureus, E. coli)
Type II: Monomicrobial; S. pyogenes (or S. aureus)
Infectino of subcutaneous tissue, fascia (often legs)
Preceded by local trauma
Sx: begins with fever; painful, red, tender swelling; progresses to grey-purple with bullae, then gangrene
Tx: Surgical debridement, antibiotics
Toxic Shock Syndrome (TSS)
S. aureus (or S. pyogenes)
Superantigen toxin (TSST-1) stimulates many T-cells, releasing cytokines
Prolongued tampon use
Sx: fever, shock, rash (including palms, soles), organ failure
Lack of TSST-1 antibody increases susceptibility
Bacterial Meningitis - Sx
Headache, fever, photophobia, neck stiffness, Kernig’s & Brudzinski’s signs
Late: Confusion, stupor Coma
Bacterial Meningitis - Lab findings
Elevated opening pressure
Elevated WBC (>80% PMNs)
Elevated protein
Decreased glucose
Bacterial Meningitis - Top 5
Neisseria meningitidis Listeria monocytogenes Haemophilus influenzae Streptococcus agalactiae (Group B) Streptococcus pneumoniae
*Rocky Mountain spotted fever - Sx
- fever
- severe headache
- myalgia
- arthralgia
- nausea
- evolving rash (start as macular –> maculopapular –> petechial), begins day 3-5
- rash begins on ankles & wrists, spreads centrally & palms & soles
*Ehrlichia - Sx
- fever, malaise, myalgia, chills
- thrombocytopenia & leukopenia
*Rickettsialpox - Sx
- single painless red papule at site of mite bite (initial Sx) –> vesicular –> eschar
- fever, chills, myalgia, headache, diffuse rash