Clinical Microbiology — SCT II [Vol. 1] Flashcards
Mention 5 diseases that are frequently caused by Staphylococcus aureus!
- Folliculitis
- Frunculus
- Bullous impetigo
- Osteomyelitis
- Food poisoning
- Pneumonia
Mention 2 toxin-mediated staphylococcal diseases!
- Toxic shock syndrome (TSS)
- Scalded skin syndrome
- Food poisoning
Mention 3 toxic products produced by Staphylococcus aureus
- TSST (Toxic shock syndrome toxin)
- Enterotoxin
- Exfoliatin
- Leukocidins
- Hemolysins
Which is the most virulent species of the Staphylococcus genus?
S. aureus
Which enzymatic virulence factor is characteristic exclusively for Staphylococcus aureus?
Exocoagulase
Which biochemical test can be used to differentiate staphyloccoci from streptococci?
Catalase test
Which antibacterial drug is the first choice in serious infections caused by methycillin sensitive Staphylococcus aureus (MSSA) strains?
Oxacillin (cloxacillin, flucloxacillin)
Which antibacterial drug is the first choice in serious infections caused by methycillin resistant Staphylococcus aureus (MRSA) strains?
Glycopeptides (vancomycin, teicoplanin)
In which diseases is Staphylococcus saprophyticus considered an obligate pathogen?
Cystitis in young women
Which cell constituents determine the group-specific, and the type specific antigens of Streptococcus pyogens, respectively?
Group specific: C-polysaccharide
Type specific: M protein
Mention 3 enzymes produced by Streptococcus pyogens that enhance the spread of the bacterial infection in the body!
- Streptokinase (fibrinolysin)
- Hyaluronidase
- Streptodornase (DNAse)
List 3 diseases caused by Streptococcus pyogens in the skin or in subcutaneous tissues!
- Impetigo
- Erysipelas
- Cellulitis
- Necrotizing fasciitis
- Myonecrosis
Mention a toxin-mediated streptococcal disease; specify the name of the toxin and its mechanism of action!
- Scarlet fever — erythrogenic toxin — superantigen causing capillary destruction
- Streptococcal toxic shock syndrome (TSS) - TSST - superantigen
Mention 2 poststreptococcal diseases!
- Glomerulonephritis
- Rheumatic fever
- Erythema nodosum
- Chorea minor
Which product of Streptococcus pyogens has a major pathogenic role in poststreptococcal diseases?
M protein: may induce hypersensitivity reactions
How long does immunity against scarlet fever exist? Which immune effector mechanism is involved?
Life-long immunity. Antitoxic antibodies are involved.
What is the drug of first choice in Streptococcus pyogens infection?
- Penicillin-G
- Pencillin V / Amoxicillin
What is the patomechanism of post-streptococcal rheumatic fever?
Type II hypersensitivity (cytotoxic antibodies)
What is the patomechanism of post-streptococcal glomerulonephritis?
Type III hypersensitivity (immune complexes)
Which Streptococcus special plays a major role in the meningitis of newborn babies?
Group B Streptococcus (S. agalactiae)
What is (are) the major causative agent(s) for native valve infective endocarditis?
Viridans streptococci
Mention 2 diseases that are frequently caused by enterococci
- Urinary tract infections
- Endocarditis
- Intrabdominal and pelvic infections
What are the specific morphologic features of Streptococcus pneumoniae?
- Gram positive diplococcus
- Lancet shape
- Capsule
Mention 3 diseases that are frequently caused by Streptococcus pneuomoniae
- Pneumonia
- Meninigitis
- Sinusitis
- Otitis media
- Sepsis
What fast diagnostic procedure can be used in acute Neisseria gonorrhoeae infection?
Demonstration of bacteria (intracellular in PMNs) from urethral discharge by Gram or methylene blue stain; PCR amplification of bacterial DNA
