Minimum questions 1 Flashcards
What does sterilization mean?
Killing procedure of any kind of germs
What does disinfection mean?
Procedure where the number of germs are reduced to a safety level
Which parameters can influence the effectivity of the sterilization? (6)
- Number of germs
- Resistance of germs
- Concentration of the disinfectants
- Presence of organic materials
- Initial time
- Presence of biofilm
Parameters of the hot-air sterilization cupboard protocol?
180°C - 1 hour
160°C - 2 hours
140°C - 3 hours
Parameters of the autoclaving?
+1 atm overpressure - 121°C - 20-30 minutes
+2 atm overpressure - 134°C - 10 minutes
Chemical agents used for gas sterilization? (3)
Ethylene oxide
Formaldehyde
Beta-propiolacton
Theoretical background of plasma sterilisation?
Hydrogen peroxide in high electric field will form plasma stage. The produced free radicals will kill the microbes. At the end of the procedure will be produced water, oxygen and other non toxic products
Biological method used for checking the effectivity of sterilisation?
By bacillus / geobacillus stearothermophilus spores. If the procedure was performed in the right way, the spores cannot be cultivated
Detection of the presence of pyrogenic material in drugs?
LAL test ; the blood of horseshoe crab will coagulate in the presence of the LPS
What are the disinfectants?
Chemical agents used on inanimate / non-living surfaces
What are antiseptic agents?
Chemical agents used for disinfection on animate (tissue, skin, mucous membrane) surfaces
What does serological reaction mean?
Reaction based on the Ag/Ab reaction performed in vitro
What does agglutination mean?
Serological reaction where the antigen is cell mediated
What are the bacterial cell surface antigens?
O : cell wall
H : flagella
K : capsule
What does antibody titre mean?
The highest dilution fold or the lowest antibody concentration where we can see in vitro Ag/Ab reaction
What does precipitation mean?
Serological reaction where the antigen is soluble (enzyme, toxin or virus particle)
What does iatrogenic infection mean?
Infection caused by medical staff during the investigation or treatment
What does nosocomial infection mean?
Infection occurred in hospital after 48 hours of the hospitalisation
What are the contents of the vaccines?
Live attenuated microbe ; killed microbe, toxoid, antigens of the microbe
What does native examination of the microbe mean in microbiology?
The microbe is examined without killing procedure
What kind of information can we get by light microscopical examination? (4 examples)
- Size of the microbe
- Shape of microbe
- Motility
- The staining
The solutions of the Gram stain? (5)
- Sodium oxalate
- Crystal violet
- Iodine solution
- 96% ethanol
- Fuschin or safranin
What kind of devices can be used for anaerobic cultivation?
- Anaerostate
- Gas-pack jar
- High agar
- Anaerobic chamber
What is a bacteriostatic? A bactericide?
Bacteriostatic : inhibits bacterial growth
Bactericide : kills bacteria
What is selective toxicity?
The antibiotic has an effect only on the bacteria, but not on the human host
Chemotherapeutic index
Dosis tolerata maxima (DTM) / dosis curativa minima (DCM)
Cell wall synthesis inhibitor antibiotics? (4)
- Penicillin
- Cephalosporin
- Carbapenem
- Glycoeptide
Glycopeptide antibiotics (2)
- Vancomycin
2. Teicoplanin
Membrane function alternating antibiotic?
Polymixines
What are the protein synthesis inhibitor antibiotics? (5)
- Aminoglycosides
- Tetraclycline
- Macrolide
- Chloramphenicol
- Linezoid
Nuclei acid synthesis inhibitors are..? (2)
- Quinolones
- Rifampicin
- Nitroimidazoles
Three possible ways of horizontal gene transfer
- Conjugation (plasmid)
- Transduction (bacteriophage)
- Transformation (update of naked DNA from the environment)
Antibiotic resistance mechanism ? (3)
- Enzymatic degradation or modification of the antibiotics
- Efflux pump
- Modifying of the antibiotic binding site
What does MRSA mean?
Methicillin-resistant staphylococcus aureus
What does ESBL mean?
Extended spectrum of beta lactamase enzyme
What does MIC mean?
Minimal bacteriostatic concentration of an antibiotic measured in microg/mL
What does MBC mean?
Minimal bactericidal concentration of an antibiotic measured in microL/mL
Definition of MBL
Metallo-beta-lactamase (= carbapenemase)
Definition of MACI
Multi-resistant acinetobacter
Definition of PACI
Pan resistant acinetobacter
Which 3 vaccines contain capsular polysaccharide?
- HIB (against haemophilus influenzae type b)
- Prevenar / pneumovac (against 13 / 23 serotypes of streptococcus penumoniae)
- Meningococcus vaccines (against serotypes ACWY but not B)
What kind of specimen can be sent to the microbiology diagnostic laboratory in the case of atypical pneumonia?
Blood, urine, broncho-alveolar lavage
What kind of bacterial infection can be treated by antitoxin? (3)
Infections caused by bacterial exotoxins : Tetanus, botulism, diphteria
Which bacteria can be differenciated with the catalase test?
Staphylococci (+) and streptococci (-)
Which bacteria can be differenciated with the coagulase test?
Staphylococcus aureus (+) and the other staphylococcus species (-) aka ‘coagulase-negative staphylococci’
Microscopic morphology of staphylococci
Gram positive cocci, arranged in grape-like structures
Colony morphology of staphylococcus aureus on blood agar plate
Average size, round of colonie with butter consistency, golden pigment production and beta haemolysis
What are the non-toxic virulence factors of the staphylococcus aureus? (3)
- Protein A
- Endocoagulase (clumping factor)
- Hialuronidase
What are the toxic virulence factors of staphylococcus aureus?
- Leudocidin,
- Toxic shock syndrome toxin,
- Exfoliative toxin,
- Enterotoxin,
- Haemolysin
Disease caused by staphyloccocus aureus? (7)
- Folliculitis
- Furuncle
- Carbuncle
- Impetigo
- Pneumonia
- Osteomyelitis
- Food poisoning
Diseases caused by staphylococcus aureus exotoxins? (3)
- Food poisoning
- Scalded skin syndrome
- Toxic shock syndrome
List at least 2 coagulase-negative staphylococcus species
S. epidermidis,
S. saprophyticus,
S. haemolyticus,
S. lugdunensis
.Diseases caused by coagulase negative staphylococci? (2)
- Nosocomial infections
- Biofilm production on the surface of plastic devices
Which bacterium can cause “Honeymoon cystitis”?
Staphylococcus saprophyticus
Colony morphology of Streptococcus pyogenes on blood agar plate (morphology)
Small, pin point colonies, surrounded by large, strong beta-haemolytic zone
Which streptococci show beta-haemolysis? (2)
Streptococcus pyogenes
Streptococcus agalactiae
Which streptococci show alpha-haemolysis? (2)
Streptococcus pneumoniae and viridans streptococci (e.g S mutans, S. mitis, S. salivarius)
Which species is the Lancefield group A streptococcus?
Streptococcus pyogenes
Which species is the Lancefield group B streptococcus?
Streptococcus agalactiae
What is the causative agent of the scarlet fever?
Streptococcus pyogenes
What bacterial virulence factor is the causative agent of scarlet fever?
Streptococcus pyrogenic exotoxin or erythrogenic toxin
What is the capsule of S. Pyogenes made of?
Hyaluronic acid
Disease caused by streptococcus pyogenes? (3)
Pharyngitis, tonsilitis, sinusitis
What kind of post streptococcal infections can be caused by streptococcus pyogenes? (2)
Acute rheumatic fever, glomerulonephritis
Which 2 streptococcus species show 100% penicillin sensitivity still now?
Streptococcus pyogenes and streptococcus agalactiae
What kind of disease can be caused in new-borns by streptococcus agalactiae? (3)
Meningitis, sepsis, pneumonia
Which bacterium is the leading cause of neonatal meningitis?
Streptococcus agalactiae
Microscopic morphology of streptococcus pneumoniae?
gram positive diplococci
How can we prevent diseases caused by streptococcus pneumoniae? (2)
By 23 valent polysaccharide capsule vaccine, or by 13 valent conjugated vaccine
Which two bacteria can be differentiated based on their optochin sensitivity / resistance?
S. pneumoniae (S) and viridans streptococci (R)
What kind of disease can be caused by viridans group streptococci? (2)
Dental decay or endocarditis
Which are the 2 most frequent human pathogenic Enterococcus species?
E. faecalis and E. faecium
Microscopic morphology of Neisseria gonorrhoeae?
Gram negative, non capsulated diplococci
What kind of culture media can be used to cultivate Neisseria gonorrhoeae? (2)
Chocolate agar or Thayer Martin agar
Microscopic morphology of Neisseria meningitidis?
Gram-negative, capsulated, diplococci
How can neisseria meningitidis spread?
By respiratory droplets that will colonize the nasopharynx
What kind of disease can be caused by Neisseria meningitidis? (3)
- Sepsis
- Meningitis
- Waterhouse-Friderichsen syndrome
What kind of diseases can be caused by Neisseria gonorrhoeae? (4)
- Gonorrhoea
- Blenorrhoea neonatorum
- Proctitis
- Orchitis
What is the causative agent of Waterhouse-Friderichsen syndrome?
Neisseria meningitidis
What kind of tests can be performed from liquor in case of Neisseria meningitidis infection?
- Microscopic examination
- Gram stain
- Latex agglutination
What can be done as prophylactics for a person who has been in contact with Neisseria meningitidis?
Chemoprophylaxis by rifampicin or ciprofloxacin
What can Nesseria gonorrhoeae cause in newborns?
Ophthalmoblenorrhoea neonatorum
Which serotype of Haemophilus influenzae can cause invasive infection?
The haemophilus influenzae with capsule “b” serotype
How can we prevent invasive infections caused by haemophilus influenzae strains?
By Hib vaccine
What kind of disease can be caused by haemophillus ducreyi?
Ulcus molle (chancroid)
What is the causative agent of whooping cough?
Bordetella pertussis
What are the virulence factor of Bordetella pertussis (2)?
Fimbria, pertussis toxin
What is the causative agent of tularemia?
Francisella tularensis
What are the causative agents of human brucellosis? (4)
- Brucella abortus
- Melitensis
- Suis
- Canis
What are the diseases caused by bacillus anthracis? (3)
- Cutaneous anthrax,
- pulmonary anthrax,
- gastrointestinal anthrax
What kind of disease can be caused by bacillus cereus? (2)
- Food poisoning
- Wound infection
What is the causative agent of pseudomembranosus colitist?
Clostridium difficile
What kind of bacteria can cause flaccid paralysis?
Clostridium botulinum
What kind of bacteria can cause spastic paralysis?
Clostridium tetani
What is the treatment of Botulism?
giving polyvalent antitoxin
What is the treatment of pseudomembranosus colitis? (3)
- Vancomycin per os,
- metronidazole,
- faecal transplantation
Which bacteria can cause gas gangrene? (3)
- Clostridium perfringens
- Clostridium histolyticum
- Clostridium septicum
What is the causative agent of diphteria?
Corynebacterium diphteriae
How can we detect the toxin of corynebacterium diphteriae? (2)
- Elek’s test
- Römer test (in guinea pigs)
What is the treatment of diphteria? (3)
- Passive immunisation
- Giving antibiotics
- Artificial ventilation if necessary
Which bacteria belong to diphteroid group?
- Corynebacterium pseudodiphtheriticum
- Corynebacterium ulcerans
- Corynebacterium minutissimum
- Corynebacterium urealyticum
What are the diseases caused by Listeria monocytogenes in kids? (3)
- meningitis
- sepsis
- granulomatosis infantiseptica
What are the diseases caused by Listeria monocytogenes in adults? (4)
- Gastrointestinal symptoms
- Meningitis
- Sepsis
- Endocarditis
What is the treatment of Listeriosis?
Ampicillin-gentamicin is the drug of choice
What is the causative agent of erysipeloid?
Erysipelothrix rhusiopathiae
Which bacteria can cause dental decay? (2)
Lactobacilli and streptococcus mutans
Which bacteria can cause human tuberculosis? (3)
- Mycobacterium tuberculosis
- Mycobacterium bovis
- Mycobacterium africanum
What kind of staining can be used to stain mycobacteria?
Ziehl-Neelsen staining
How long can be cultivated the causative agent of human tuberculosis
on Lowenstein-Jensen culture media?
6-8 weeks
How can be prevented the human tuberculosis?
By BCG vaccine
What are the facultative pathogenic mycobacteria? (4)
- Mycobacterium avium komplex
- Mycobacterium kansasii
- Mycobacterium marinum
- Mycobacterium ulcerans
Which mycobacteria is apathogenic?
Mycobacterium smegmatis
What is the causative agent of leprosy?
Mycobacterium leprae
What are the types of leprosy? (2)
- Tuberculoid
- Lepromatosus leprosy
What is the treatment of leprosy? (3)
- Dapson
- Clofazimin
- Rifampicin
How can Nocardia stain?
It is gram positive and zhiel neelsen positive
What are the most important Actinomyces species? (3)
- Actinomyces israelii
- Astinomyces naeslundii
- Astinomyces odontolyticus
Which E. coli can be toxin producer? (5)
- ETEC
- EPEC
- EAEC
- EIEC
- EHEC
What kind of extra intestinal disease can be caused by Escherichia
coli? (3)
- Urinary tract infections
- Neonatal meningitis
- Sepsis
What are the causative agent of typhoid fever? (4)
- Salmonella Typhi
- Salmonella Paratyphi A, B, C
Which bacteria can cause salmonellosis? (3)
- Salmonella Enteritidis
- Salmonella Typhimurium
- Salmonella Choleraesuis
What is the causative agent of dysentery? (3)
- Shigella dysenteriae
- Shigella flexneri
- Shigella sonnei
Which bacterium is the causative agent of plague?
Yersinia pestis
What is the spreading way of the plague?
By the bite of the rat flea or by respiratory droplets
What are the diseases caused by Klebsiella pneumoniae? (4)
- Lobar (friedländer) pneumonia
- Wound infection
- Bloodstream infection
- Urinary tract infection
What is the causative agent of cholera?
Vibrio cholerae
What kind of Vibrio species can cause human diseases? (3)
- Vibrio cholera
- Vibrio parahaemolyticus
- Vibrio vulnificus
What are the characteristic biochemical properties of pseudomonas aeruginosa? (2)
- Obligate aerobic
- Oxidase positive
Colony morphology of Pseudomonas aeruginosa?
Bacteria can produce water soluble pigment that stains the culture media, the colonies have grape like smells
Microscopic morphology of Pseudomonas aeruginosa?
Gram-negative rod
What are the most frequent diseases caused by Pseudomas
aeruginosa? (2)
- Nosocomia lung infections
- Wound and blood stream infections
What is the treatment of the diseases cause by Pseudomonas
aeruginosa?
Multiresistant, based on antibiogram
What is the most common source of the infection caused by
Acinetobacter baumanii?
Hospital environment
What does MACI mean in microbiology?
Multiresistant Acinetobacter baumannii
What is the most common infection caused by Stenotrophomonas
maltophila? (2)
- Nosocomial lung infection
- Sepsis
What is characteristic for antibiotic sensitivity of Stenotrophomonas
maltophila?
Multiresistant
How can legionella pneumophila spread?
by aerosol
What is the diagnosis of Legionellosis? (2)
- By serology from blood
- By immune chromatography form urine
Which bacterium can cause chronic gastritis or stomach ulcer?
Helicobacter pylori
What is the most important cultivable anaerobic member of the normal
flora of the large bowel?
Bacteroides fragilis
Which genera belongs to the Spirochaetales order? (3)
- Treponema
- Borrelia
- Leptospira
What are the causative agents of Plaut-vincent angina? (2)
- Treponema vincentii
- Fusobacteria
What is the causative agent of syphilis?
Treponema pallidum subspecies pallidum
How can syphilis spread? (4)
- By sexual contact,
- transplacental, by blood
- transfusion
- by organ
transplantation.
What is the first symptom in syphilis?
Ulcus durum - painless hard ulcer, enlarged lymph nodes
In which stage of the syphilis can appear rash all over the body?
2nd stage
In which stages is syphilis contagious?
1st and 2nd stages and in the first 2 years of the latency.
At the 3rd stage only in utero infections may occur
When can develop neurosyphilis during the infection?
In all stages of the diseases can develop neurophylis
What is the specific diagnosis of syphilis? (3)
- ELISA
- TPHA
- TPPA
When can we use which non treponemal serological reactions during infection by syphyllis? (3)
- RPR and VDRL are used to determine the stages of syphilis
- To detect reinfection
- To control the efectiveness of the therapy
What are the non-specific treponemal serological reactions? (2)
- RPR
- VDRL
What kind of diseases can be caused by Borrelia? (2)
- Lyme diseases and relapsing fever
How can the Lyme disease spread?
By a bite of a tick
What are the causative agents of Lyme disease? (3)
- Borrelia burgdorferi
- Borrelia afzelli
- Borrelia garini
What is the causative agent of epidemic relapsing fever?
Borellia recurrentis
What is the vector of Lyme diseases?
Tick
What is the vector of Borrelia recurrentis?
Body louse
What is the molecular background of relapsing fever?
Bacterial antigen changing.
What is the first symptom of Lyme diseases?
Erythema chronicum migrans
What is the causative agent of Weil’s diseases?
Leptospira icterohaemorrhagiae
What are the characteristic properties of the meningitis caused by
Leptospira?
Serosus, non-purulent
What is the source of the infection caused by Leptospira?
Zoonotic diseases, can spread by the urine of animals
How can the Lyme diseases diagnosed? (3)
- Serology
- ELISA screening test
- Immunoblot is used for confirmation
Which bacteria cannot have cell wall? (2)
- Mycoplasma
- Ureaplasma
Which bacteria can cause atypical pneumoniae? (3)
- Mycoplasma pneumoniae
- Chlamydophila pneumoniae
- Legionella pneumophila
What is the causative agent of typhus exanthematicus?
Rickettsia prowaczekii
What is the causative agent of Q-fever?
Coxiella burnettii
What is the causative agent of parrot fever?
Chlamydia psittaci
What is the causative agent of trachoma?
Chlamydia trachomatis, serotype A-C
What kind of disease can be caused by Chlamydia trachomatis
serotype L1-L3?
Lymphogranuloma venereum
What is the effect of the bacterial AB exotoxins?
- Neurotoxins
- Protein synthesis inhibitors
- Ion secretion enhancers
What is the effect of the cholera toxin?
- Increasing cAMP
- Enhancing ion secretion
What are the causative agents of impetigo contagiosa? (2)
- S. aureus
- S. pyogenes
What is the causative agent of erysipelas?
Streptococcus pyogenes
What is the causative agent of Trachoma?
Chlamydia trachomatis A,B,C
What is the causative agent of Ophtalmoblenorrhoea neonatorum?
Neisseria gonorrhoeae
List 4 capsulated bacteria
- Streptococcus pneumoniae
- Streptococcus agalactiae,
- Streptococcus
pyogenes, - Escherichia col
How many percentage of the adults are carrier of Staphylococcus. aureus?
20-30%
How many different kind (serotype) of capsule can be produced by
Streptococcus pneumoniae?
94 (or 90-100)
What is the most common causative agent of community acquired pneumonia?
Streptococcus pneumoniae
What kind of vaccines can be used to prevent invasive diseases caused by
Streptococcus pneumoniae
- Prevenar-13 : streptococcus pneumoniae 13 type of capsule conjugated to toxoid - recommended for new borns and elderly
- Pneumovax : streptococcus pneumoniae 23 type of capsule - recommended for adults and teenagers