Gram-positive Bacteria Flashcards
Virulence factor of Staphyloccus aureus that binds IgG, preventing opsonization and phagocytosis
Protein A
Most common cause of acute infective endocarditis
Staphylococcus aureus
Genes encoding methicillin-resistance in Staphylococcus aureus
SCCmec (staphylococcal cassette chromosome conferring resistance to methicillin) / mecA
Drug of choice against Staphylococcus epidermidis
Vancomycin
Toxin causing staphylococcal scalded skin syndrome
Exfoliatin
TSST-1 causes this syndrome
Toxic shock syndrome
The only bacterium with a capsule composed of protein (poly-D glutamic acid)
Bacillus anthracis
Woolsorter’s disease is also known as
Pulmonary anthrax
In Bacillus anthracis, the genes for exotoxins are encoded in this plasmid
pXO1
Bacillus cereus secretes a heat-labile and a heat-stable toxin. The heat-labile toxin, similar to the enterotoxin of cholera and the LT from Escherichia coli, causes nausea, abdominal pain and diarrhea that lasts for:
12-24 hours
Exotoxin released by Clostridium tetani
Tetanospasmin
Type of muscle paralysis in botulism
Flaccid paralysis
The tetanus toxin acts on these cells, preventing the release of GABA and glycine, which are inhibitory neurotransmitters
Renshaw cell interneurons
A grotesque grinning expression due to spasm of facial muscles exhibited by patients with tetanus is known as:
Risus sardonicus
Booster shots of tetanus toxoid vaccine are given every:
10 years
Bacteria that causes pseudomembranous colitis
Clostridium difficile
Gas gangrene is caused by:
Clostridium perfringens
These enzymes are responsible for beta hemolysis in Streptococcal organisms
Streptolysins O and S
Scarlet fever is caused by this toxin released by S. pyogenes
Pyrogenic / Erythrogenic exotoxin
Three most common pathogens associated with meningitis in infants younger than 3 months
Group B Streptococcus (most common)
Listeria monocytogenes
Escherichia coli
When pneumococci on a slide smear are mixed with a small amount of anti serum (serum with antibodies to the capsular antigens) and methylene blue, the capsule will appear to swell. Identify this reaction.
Quellung reaction
Three main causes of otitis media
Streptococcus pneumoniae (~30% of cases) Haemophilus influenzae (~25%) Moraxella catarrhalis (~15-20% )
Chest x-ray finding in post-viral Staphylococcal pneumonia
Pneumatocele formation
Most common cause of osteomyelitis and septic arthritis
Staphylococcus aureus
Usual food source in Staphylococcal gastroenteritis
Salad made with mayonnaise
Most common cause of prosthetic valve endocarditis, septic arthritis in prosthetic joints, and ventriculoperitoneal shunt infections
Staphylococcus epidermidis
Second most common cause of urinary tract infection in sexually active women
Staphylococcus saprophyticus
Honey colored crust is a manifestation of this skin infection caused by Streptococcus pyogenes
Impetigo
Toxin responsible for necrotizing fasciitis from Streptococcus pyogenes
Exotoxin B
Most common bacterial cause of sore throat
Streptococcus pyogenes
Three clinical conditions that can present with strawberry tongue
Kawasaki disease
Scarlet fever
Toxic shock syndrome
Susceptibility test used in scarlet fever
Dick test
Test used to determine antecedent streptococcal skin infection
Anti-DNAse
Most common antecedent infection in poststreptococcal glomerulonephritis
Pyoderma
Most common cause of neonatal pneumonia, sepsis, and meningitis
Streptococcus agalactiae
Cause of endocarditis in patients who underwent gastrointestinal tract surgery
Enterococcus faecalis
Etiology of marantic endocarditis in patients with abdominal malignancy
Streptococcus bovis
Most common cause of dental caries
Streptococcus mutans
Most common cause of subacute and native valve endocarditis
Streptococcus sanguinis
This viridans Streptococcus can cause brain abscesses
Streptococcus intermedius
Most common cause of community-acquired pneumonia, acute otitis media, bacterial sinusitis, and meningitis in adults and the elderly
Streptococcus pneumoniae
Drug of choice in infections causes by most streptococcal infections
Penicillin
Gastroenteritis from reheated fried rice is usually caused by what organism
Bacillus cereus
Treatment for gastroenteritis caused by Bacillus cereus
Supportive
Drug of choice for Bacillus anthracis
Ciprofloxacin
Type of paralysis in botulism
Flaccid
Floppy baby syndrome is caused by:
Clostridium botulinum
Most common cause of Clostridium difficile colitis is prolonged treatment with this antibiotic
Clindamycin
Aside from clindamycin, these cell wall inhibitors are also common causes of Clostridium difficile colitis
Second and third generation cephalosporins
What is the most common cause of necrotizing fasciitis?
Streptococcus pyogenes
Gas within the muscle in clostridial myonecrosis produces this characteristic clinical finding
Crepitation
Drug of choice for tetanus infection
Penicillin G
An arched posture of extreme hyperextension of the body seen in tetanus
Opisthotonos
Type of paralysis in tetanus
Spastic
Etiology of pseudomembranous pharyngitis
Corynebacterium diphtheriae
Granulomatosis infantiseptica is also known as:
Early-onset neonatal listeriosis
Drug of choice for anthrax
Ciprofloxacin
Toxin that cleaves SNARE proteins such as SNAP 25, syntaxin, and synaptobrevin
Botulinum toxin
Toxin that cleaves synaptobrevin inhibiting the inhibitory neuron release or firing
Tetanus toxin
Bacterium with a deeply staining metachromic granules giving a beaded appearance
Corynebacterium diphtheriae
Drug of choice for CNS Listeria sp. infection in patients allergic to penicillin
Trimethoprim sulfamethoxazole
Catalase and coagulase positive Gram positive organism that produces yellowish colonies
Staphylococcus aureus
Toxin of S. aureus that lyses WBCs and acts as an important virulence factor
Panton valentine leukocidin
Fifth generation cephalosporin with coverage for MRSA
Ceftaroline
Drug used to eradicate nasal carrier state of S. aureus
Rifampin
Bacitracin sensitive and PYR+ Streptococcus causing significant human disease
S. pygogenes
Streptococcus that grows in bile and 6.5% NaCl implicated in abdominal abscesses, urinary tract infection, and endocarditis
Group D Streptococci
Streptococcus that grows in bile but not in 6.5% NaCl, implicated in bacteremia among colon cancer patients
S. bovis
Gram positive, non acid fast, obligate anaerobe with branching filaments
Actinomyces spp.
Gram positive, acid fast, obligate aerobe with branching filaments
Nocardia spp.
Virulence factor of Streptococci which induces antibodies that react with human cardiac sarcolemma implicated in rheumatic fever
M protein
Also known as spreading factor of Streptococci causing breakdown in the ground substance of connective tissue
Hyaluronidase
ASO titer cutoff suggestive of recent streptococcal infection
160-200 units
Agent responsible for the hemolytic zones around streptococcal colonies on blood agar
Streptolysin S
Most common infection caused by GABHS
Pharyngitis
Impetigo could lead to this autoimmune complication
Glomerulonephritis
Poststreptococcal autoimmune complications develop how long after infections?
1-4 weeks
Two serologic tests that are more specific for streptococcal cutaneous infections
Anti DNAse
Anti hyaluronidase
Drug of choice for Streptococcus pyogenes infection
Penicillin G
Bacteremia from S. pneumoniae causes this triad of complications
Arthritis
Endocarditis
Meningitis
Drug of choice for mild pneumonia
Amoxicillin
Main virulence factor of S. pneumoniae
Polysaccharide capsule
Drug of choice for anthrax
Ciprofloxacin
Toxin that cleaves SNARE proteins such as SNAP 25, syntaxin, and synaptobrevin
Botulinum toxin
Toxin that cleaves synaptobrevin inhibiting the inhibitory neuron release or firing
Tetanus toxin
Bacterium with a deeply staining metachromic granules giving a beaded appearance
Corynebacterium diphtheriae
Drug of choice for CNS Listeria sp. infection in patients allergic to penicillin
Trimethoprim sulfamethoxazole
Catalase and coagulase positive Gram positive organism that produces yellowish colonies
Staphylococcus aureus
Toxin of S. aureus that lyses WBCs and acts as an important virulence factor
Panton valentine leukocidin
Fifth generation cephalosporin with coverage for MRSA
Ceftaroline
Drug used to eradicate nasal carrier state of S. aureus
Rifampin
Bacitracin sensitive and PYR+ Streptococcus causing significant human disease
S. pygogenes
Streptococcus that grows in bile and 6.5% NaCl implicated in abdominal abscesses, urinary tract infection, and endocarditis
Group D Streptococci
Streptococcus that grows in bile but not in 6.5% NaCl, implicated in bacteremia among colon cancer patients
S. bovis
Gram positive, non acid fast, obligate anaerobe with branching filaments
Actinomyces spp.
Gram positive, acid fast, obligate aerobe with branching filaments
Nocardia spp.
Virulence factor of Streptococci which induces antibodies that react with human cardiac sarcolemma implicated in rheumatic fever
M protein
Also known as spreading factor of Streptococci causing breakdown in the ground substance of connective tissue
Hyaluronidase
ASO titer cutoff suggestive of recent streptococcal infection
160-200 units
Agent responsible for the hemolytic zones around streptococcal colonies on blood agar
Streptolysin S
Most common infection caused by GABHS
Pharyngitis
Impetigo could lead to this autoimmune complication
Glomerulonephritis
Poststreptococcal autoimmune complications develop how long after infections?
1-4 weeks
Two serologic tests that are more specific for streptococcal cutaneous infections
Anti DNAse
Anti hyaluronidase
Drug of choice for Streptococcus pyogenes infection
Penicillin G
Bacteremia from S. pneumoniae causes this triad of complications
Arthritis
Endocarditis
Meningitis
Drug of choice for mild pneumonia
Amoxicillin
Main virulence factor of S. pneumoniae
Polysaccharide capsule