Term
| Strep. pyogenes (Virulence factors)(10) |
|
Definition
Protein F: mediates cell attachment
M Protein: prevents phagocytosis
Lipoteichoic acid: attachment
Enzymes:
-Streptolysin O: ASO antibodies
-Streptolysin S: beta hemolysis
-Streptokinase: spread
-DNase: spread
-Hyaluronic acid: Capsule
-C5a peptidase: disrupt inflammation
Streptococcal pyogenic enzymes (SPE) |
|
|
Term
| Strep. pyogenes (Spectrum of diseases) (9) |
|
Definition
| Pharyngitis, Impetigo, Erysipelas, Necrotizing faciitis: caused by SPE, Toxic shock syndrome: caused by SPE, Bacteremia, Rheumatic fever, Scarlet fever, Cellulitis |
|
|
Term
| Strep. pyogenes (Treatment)(3) |
|
Definition
| Penicillin, 3rd gen. cephlasporins, Vancomycin* |
|
|
Term
| Strep. agalactiae (Virulence factors) (1) |
|
Definition
| C antigen, capsule interferes w/phagocytosis |
|
|
Term
| Strep. agalactiae (Spectrum of diseases) (8) |
|
Definition
| Bacteremia, Pneumonia, Meningitis, Bone/Joint infections, Skin and soft tissue infection, Urinary infection, Wound infection, Postpardum Endometritis* |
|
|
Term
| Strep. agalactiae (Treatment) (3) |
|
Definition
| Penicillin, 3rd gen. cephlasporins, Vancomycin* |
|
|
Term
Groups C, F, and G (Virulence factors)
Strep. anginosus
constellatus
intermedius |
|
Definition
None identified
*ALPHA hemolytic |
|
|
Term
Groups C, F, and G (Spectrum of diseases)
Strep. anginosus
constellatus
intermedius |
|
Definition
| Similar to pyogenes and agalactiae |
|
|
Term
Groups C, F, and G (Treatment)
Strep. anginosus
constellatus
intermedius |
|
Definition
| Penicillin, 3rd gen. cephlasporins, Vancomycin* |
|
|
Term
| Strep. pneumoniae (Virulence factors) (7) |
|
Definition
Polysaccharide capsule: evades phagocytosis
Surface adhesins
F antigen
Phosphocholine: regs. cell wall hydrolysis
Secretory IgA protease: destroys IgA
Pneumolysin: invasion
Hydrogen peroxide |
|
|
Term
| Strep. pneumoniae (Spectrum of diseases) (5) |
|
Definition
| Pneumonia, Sinusitis, Otitus media, Meningitis, Bacteremia |
|
|
Term
| Strep. pneumoniae (Treatment)(3) |
|
Definition
| Penicillin, 3rd gen. cephlasporins, Vancomycin* |
|
|
Term
| Strep. viridans (Virulence facotors) |
|
Definition
none mentioned
ALPHA hemolytic* |
|
|
Term
| Strep. viridans (Spectrum of diseases) (4) |
|
Definition
| Endocarditis, Bacteremia, Brain abcess, Oropharynx |
|
|
Term
| Strep. viridans (Treatment) (3) |
|
Definition
| Penicillin, 3rd gen. cephlasporins, Vancomycin* |
|
|
Term
Enterococci sp. (Virulence factors) (3)
-E. facium
-E. faecalis |
|
Definition
Adhesins
-Cytolysin: hemolytic activity
-Gelatinase: protection
Inherent resistance |
|
|
Term
Enterococci sp. (Spectrum of diseases) (6)
-E. facium
-E. faecalis |
|
Definition
| Endocarditis, GI infections, Genitourinary infections: UTI and Peritonitis, Bacteremia |
|
|
Term
Enterococci sp. (Treatment) (6)
-E. facium
-E. faecalis |
|
Definition
| Ampicillin, Vancomycin, Linezdid, Daptomycin, Quinupristin/Dalfopristin, Gentamicin |
|
|
Term
| Staphylococcus sp. (virulence factor) (many!!!) |
|
Definition
Protein A: inhibits clearance by antibody
5 Cytolytic toxins:
Alpha: smooth muscle, many others
Beta: phospholipids
*Specific for sphingomyelin and lipophosphotidylcholine*
Delta: wide cytolytic activity
Gamma/PVL: 6 toxins for CA-MRSA
Exfoliative Toxins:
A (ETA): heat stable; chromosomal
B (ETB): heat labile; plasmid
Serine proteases
Enterotoxins:
A: food poisoning
B: entercolitis
C/D: milk products
Toxic shock syndrome toxin (TSST-1)
Enzymes:
Coagulase: fibrin
Fibrinolysin: staphylokinase
Hylauronidase: connective tissue
Lipase: lipids
Nuclease: DNA |
|
|
Term
| Staph. aureus (Spectrum of Diseases) (13) Catalase + |
|
Definition
Staph Scalded Skin Syndrome (SSSS)
*Mostly in neonates
Food poisoning
Toxic Shock Syndrome
*Due to tampon use
Pneumonia
Skin Infections:
Folliculitis (hair follicle)
Farbuncles (boils)
Carbuncles (deep farbuncle)
Impetigo
Erysipleas (lymphatic)
Septic Arthritis (knee)
Osteomylitis (bone)
Cellulitis
Bacteremia (anywhere in body) |
|
|
Term
| Staphylococcus (Treatment) (many!!!) |
|
Definition
Methicillin Susceptible:
Penicillinase resistance penicillin
*Naficillin
*Oxacillin
*Cloxacillin
*Dicloxacillin
HA-MRSA:
Vancomycin
*Linezolid
*Daptomycin
*Quinupristin
*Dalfopristin
CA-MRSA:
If hospitalized
*Vancomycin
If out-patient
*TMP/SMX
*Clindamycin
*Doxycycline
Severe infection:
Gentamicin + Vancomycin |
|
|
Term
Staph. epidermidis (Spectrum of diseases)
haemolyticus
lugdunensis
saprophyticus |
|
Definition
Cause similar infections on foreign materials in the body:
Catheters
Shunts
Prosthetic joints
Prosthetic heart valves
S. epidermidis and S. lugdunensis cause endocarditis from prosthetic heart valves
S. saprophyticus causes urinary tract infections |
|
|
Term
| Neisseria gonorrhoeae (Virulence factors) (many!!!) |
|
Definition
Non-motile
No spores
Capsule-like negative charge
NOT a capsule
Pili: attachment; inhibits phagocytosis
Porin proteins
PorA
PorB: inhib. phagosome-lysosome fusion
Opa protein: cell-to-cell signaling
No opa= disseminated or pelvic inflamm.
RMP protein
Transferrin receptor: competes with host for iron
Lipooligiosaccharide (LOS)
Similar to LPS, but no O-side chain
Still has lipid A endotoxin
Enzymes:
IgA protease: cleaves IgA-1
Vaginal and urethral infections
β-lactamase
Strictly human pathogens
Attach to host cells by pili
Engulfed by cells of vagina and cervix
Infect the Fallopian tubes by endocytosis
LOS stimulates TNF-α
Inflammatory responsetissue damage
IgG stimulates C5a production
C5a is chemotactic for neutrophils |
|
|
Term
| Neisseria gonorrhoeae (Spectrum of Diseases) (many!!!) |
|
Definition
Acute anterior urethritis (males)
Dysuria and urethral discharge
Infection of endocervical canal (females)
Discharge, dysuria, bleeding, pain
Rectal: proctitis, anal discharge, bleeding
Pharyngeal: usually asymptomatic
Disseminated disease: rash, septic arthritis, and tenosynovitis
Pelvic inflammatory disease (Opa)
Endometritis, salpingitis, peritonitis
Salpingitis leads to infertility
Ophthalmia Neonatorum: ocular infection of newborns during passage |
|
|
Term
| Neissera gonorrhoeae (Treatment) (many!!!) |
|
Definition
Diagnosis:
Gram stain
Culture on app. Media
Antigen detection
Nucleic Acid Test
Treatment:
For uncomplicated:
Ceftriaxone
Cefixime
Disseminated:
Ceftriaxone
Cefotaxime
Cefizoxime
Spectinomycin
For PID:
Cephalosporin
Clindamycin+Gentamicin
Ceftriaxone+Doxycycline
**Cannot use penicillin due to presence of β-lactamase |
|
|
Term
| Neisseria meningitides (Virulence factors) |
|
Definition
Differences from N. gonorrhoeae:
Has a polysaccharide capsule
12 serogroups based on capsule
Only uses PorA
No β-lactamase
Strictly human pathogens
Disease occurs in absence of antibodies for the capsule
Immunity from cross-reacting antibodies
Avoid intracellular killing
LOS stim. Inflammatory response
Tissue damage |
|
|
Term
| Neisseria meningitides (Spectrum of diseases) |
|
Definition
Found in oropharynx
Infects when barrier is compromised
Bacteremia
Present with upper respiratory infection
Meningococcemia: malaise, sepsis, rash
Meningitis: headache, fever, cloudy spinal fluid and meningococci in spinal fluid
Meningoencephalitis: CNS manifestations
Cervical rigidity (Brudzinski)
Hamstring spasm (Kernig)
Petechiae
Waterhouse-Friderichsen Syndrome
(adrenal insufficiency)
Disseminated intravascular coagulation
Shock (LOS endotoxin)
Skin lesions
Meningitis is absent
Pneumonia
Arthritis
Urethritis |
|
|
Term
| Neisseria meningitides (Treatment) |
|
Definition
Predisposing factors include overcrowding, poor health, and poor living conditions.
College dorms
Military barricks
Treatment:
Penicillin
Cephalosporin
Chloramphenicol
Vaccines:
MCV-4: patients aged 2-55
MPSV-4: patients > 55
**Both vaccines contain polysaccharide capsular material from types A, C, Y, and W-135. |
|
|
Term
| Eikenella corrodens (Gram neg. bacillus) |
|
Definition
Opportunistic
Diseases: Endocarditis due to human bite or oral trauma, Causative agent for sinusitis, meningitis, pneumonia, and brain/lung abcesses
Treatmant: Penicillin, cephalosporin, tetracyclines, Flouroquinolones |
|
|
Term
| Kingella kingae (G neg coccobacillus) |
|
Definition
Normal flora of oropharynx
Diseases: Septicarthritis, endocarditis
Treatment: Penicillin, tetracycline, erythromycin, flouroquinolones, Aminoglycosides |
|
|
Term
| Clos. tetani (terminal spore) (Virulence factors) |
|
Definition
Two exotoxins:
Tetanolysin: lyses blood cells
Heat-labile hemolysin
Tetanospasmin: neurotoxin
Gene on nonconjuctive plasmid
Tetanospasmin prod. in stationary phase
One of the most potent toxins known
Toxin binds to terminal nerve ending
Translocates across cell membrane
Carried to CNS
Transferred to spinal inhibitory neurons
Suppression of inhibitory NT’s
Unrestrained firing
Uncontrolled muscle contractions |
|
|
Term
| Clos. tetani (terminal spore) (Spectrum of diseases) |
|
Definition
Trismus (lockjaw)
Risus sardonicus: facial musc contractions
Opisthotonos: persistent back spasm
Laryngospasm
Neonatal tetanus |
|
|
Term
| Clos. tetani (terminal spore) (Treatment) |
|
Definition
Treatment:
Wound cleaning
Supportive therapy
Tracheostomy
Tetanus immune globulin
Tetanus toxoid
Metronidazole
2 Vaccines available:
Toxoid vaccine: inact. toxin
Anti-toxin: antibodies |
|
|
Term
| Clos. botulinum (subterminal spore) (Virulence factors) |
|
Definition
Seven types of exotoxins (A-G)
Specific anti-toxin required to neutralize
Types A, B, E, and F are most prominent
Exotoxin protected by non-toxic proteins
Exotoxin is heat-labile
Paralysis caused by blocking ACh release |
|
|
Term
| Clos. botulinum (subterminal spore) (Spectrum of diseases) |
|
Definition
NOT an infection, but an INTOXICATION
Foodborne Botulism
Contaminated food
Nausea and dizziness
Loss of cranial nerve function
Ocular abnormalities
Death by respiratory failure
Infant Botulism **Honey**
Constipation, weakness, apneic episodes
Flaccid paralysis
Respiratory arrest
Wound Botulism
Contamination of wounds
Toxin production in wound
Inhalation botulism
Bioterrorism
High mortality |
|
|
Term
| Clos. botulinum (subterminal spore) Treatment) |
|
Definition
Supportive
Metronidazole
Penicillin
Trivalent Antitoxin
A, B, and E |
|
|
Term
| Clos. perfringens (no spores) (Virulence factors) |
|
Definition
Alpha toxin: it is a lecithinase
Lyse RBC, WBC, platelets, endothelium
Myonecrosis
Hepatotoxicity
Myocardial dysfunction
Beta toxin:
Intestinal stasis
Mucosal necrosis
Necrotizing enteritis
Epsilon toxin:
Protoxin that is activated by trypsin
Increased GI permeability
Iota toxin:
Increases vascular permeability
Necrotic activity
Enterotoxin:
Heat-labile toxin
Causes diarrhea |
|
|
Term
| Clos. perfringens (no spoores) (Spectrum of diseases) |
|
Definition
Cellulitis:
Cellular destruction w/ gas formation
Suppurative myositis:
Pus in muscle w/ no necrosis
Myonecrosis:
Caused by Alpha toxin
Muscle necrosis, shock, renal failure
Significant gas production
Food Poisoning:
Watery diarrhea and cramps
Necrotizing Entercolitis:
Associated w/ Type C strains
Beta toxin responsible for pathology |
|
|
Term
|
Definition
5 types of C. perfringens
(A-E).
Only Types A and C cause human disease
Treatment:
Surgery
Penicillin
Hyperbaric chambers
**unproven |
|
|
Term
| Clos. difficile (Virulence factors) |
|
Definition
Enterotoxin (Toxin A)
Influx of neutrophils
Increased intestinal permeability
Cytotoxin: destructs cytoskeleton in gut |
|
|
Term
| Clos. difficile (Spectrum of diseases) |
|
Definition
|
|
Term
| Clos. difficile (Treament) |
|
Definition
Discontinue offending antibiotic
Oral Vancomycin |
|
|
