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Flashcards in Midterm II (Leiel) Deck (34):

A1. Describe N. Gonorrhoea (everything; morphology, cultivation, biochemical properties, etc.).

Naturally appearance:

  • only in human beings
  • obligate human pathogen

Morphology: Diplococci

Staining: ​Gram-negative

Biochemical: Oxidase positive

Cultivation: TM (Thayer-Martin-culture media), chocolate agar, MB staining
Virulence factors:

  • adhesive fimbria
  • IgA protease

Antigenic structure: K antigen

  • sexually transmitted disease
  • Men: urethritis (-> Prostatitis, Orchitis)
  • Women: Cervicitis, urethrisits, vaginal discharge, rectal inflammation (PID - pelvis inflammatory disease)
  • Neonates: conjunctivitis (prevention: Credé eye drops)
  • Meningitis, endocarditis, arthritis (Asymmetric polyarthritis)

Facultative intracellular, invading PMNs

Therapy: Cephalosporin, Penicillin, Cephtriaxon
Immunity: local infection - no lifelong immunity


A2. List the diseases of S. Pyogenes (only name)

  • Pharyngitis
  • impetigo
  • cellulitis and erysipelas

Infections caused by the toxins:

  • Scarlet fever
  • toxic-shock syndrome 
  • necrotizing fasciitis


  • rheumatic fever (polyarthritis, heart problems, subcutaneous nodules, erythema marginatum, chorea)
  • glomerulonephritis 

In Agoston's slides:

  • Pyogenic inflammation
  • Tonsilitis
  • Otitis media
  • Puerperal fever


A3. List the causes of Dysentery.


EIEC enteroinvasive E. coli

Campylobacter bacteria


A4. Cultivation of C. Diphteria.


  • Glycerin, Blood, Cystin and tellurite (Selective)
  • Reduce the tellurite to different extent
    • Grey - Black
  • Garlic smell
  • Gravis, intermedius and mitis biotypes


  • Ivory color
  • Clotted bovine serum, egg, heart extract.
  • Rapid growth, strong volutin granule formation


A5. symptoms of Diphteria.

  • soar throat
  • fever
  • running nose
  • regional lymph node enlargement → odema on the whole neck (bull's neck) (nausea, vomiting, and painful dysphagia)


  • arrhythmias
  • heart blocks


  • affects the (Cranial) nerves of the eye, palate, pharynx, larynx, heart, and limb muscles.


A6. List gram negative coccobacilli.

  • Haemophilus
  • Brucella
  • Bordetella
  • Francisella
  • Legionella


B1. Describe E. Coli (everything; morphology, cultivation, biochemical properties, etc.).


  • Gram negative rods (2-4 μm)
  • Facultative anaerobes
  • O, K, H antigens

Biochemical properties:

  • + Dextrose, lactose, indol
  • Urease, H2S
  • Oxidase negative


  • Simple agar
  • Eosine-methylene blue - Dark purple (lactose +)

Escherichia coli infections

  • UTI
  • Neonatal meningitis

(Enterovirulent E. coli !)

  • EPEC - colitis of the newborns
  • ETEC - „Travellers’ diarrhea”
  • EHEC - Dysenteriform diarrhea (Severe, bloody enteritis, without fever); Maybe HUS
  • EIEC - Classic dysentery !
  • EAEC - Severe watery diarrhoea, often chronic (>14 days); rel. high lethality!


B2. S. Aureus diseases.


  • Furuncles, folliculitis, carbuncles
  • Impetigo
  • Infection of burnt wounds
  • Scalded skin syndrome

Respiratory system: 

  • Pneumonia

Gastrointestinal tract:

  • Enterocolitis
  • Gastroenteritis


  • Endocarditis

Urogenital tract: 

  • Chronic nephritis


  • Osteomyelitis


  • Meningitis
  • TSS (toxic shock syndrome)
  • Sepsis
  • Eye infection


Nosocomial infection:

  • by MRSA 
  • at perinatal intensive care unit 
  • at intensive care units
  • at surgery


B3. Gram positive rod non spore forming bacteria.

  • Corynebacterium diphtheria
  • Listeria monocytogenes
  • Lactobacillus acidophilus


B4. Bacteria that are related to food poisoning.

  • Staphylococcus Aureus.
  • Salmonella
  • Vibrio cholera
  • E. coli. (EHEC)
  • Listeria monocytogenes

Yersinia genus



B5. Strawberry like tongue, which bacteria?

Streptococcus pyogenes


B6. Which bacteria should have X and V factors for growth?

Haemophilus influenzae


C1. Describe Salmonella Typhi (everything; morphology, cultivation, biochemical properties, etc.).

  • Gram negative, facultative anaerobic rod
  • Obligate human pathogens

Biochemical properties

  • Glucose, H2S
  • lactose, indol, urease

Culture: selective / differentiating media !!

  • Eosin-methylene blue medium (EM): pink colonies (lactose -)

  • Brillant green or bismuth sulphite medium


  • Fecal-oral infection
  • First 2 weeks: primary bacteremia
    • bacteria entering enteral macrophages (in Peyer’s patches)
    • delivered to mesenteral lymph nodes -> blood
    • asymptomatic phase
  • Multiplication in different organs (RES)
    • liver (Kupfer cells), gall bladder
  • Second bacteremia
    • with high number of bacteria!
  • Bacteria back to small intestine with bile
    • multiplication in Peyer’s patches
    • ulceration, perforation
  • Symptoms:
    • Fever: gradually increasing to high levels („typhosus” head)

    • Diarrhoea: NOT characteristic

      • might contain blood

    • Hepatosplenomegaly

    • Roseoles on chest & belly

Possible outcomes of the infection:

  • spontaneous recovery in 1 week
  • complications:
    • temporary bacteremia - long-term bacteremia (in young children, elderly, immunosuppressed)
    • focal infections (lung, brain, implementates)
  • asymptomatic carriage !


  • Obligatory in severe cases (high fever, septicemia)
  • Maybe for children, elderly
  • Can enhance carriage !
  • Ampicillin, fluoroquinolons, 3rd gen. cephalosporins, ceftriaxone


C2. Spreading of plaque.

  • Reservoir: rodents (~200 different species) („sylvatic cycle”)
  • Transmission: rodent’s flees („urban cycle”)
  • Manifestation: bubonic, septicemic, and pneumonic plague


Urban plague

  • is maintained in rat populations
  • spread among rats or between rats and humans by infected fleas (fleas become infected during a blood meal from a bacteremic rat)
  • urban plague has been eliminated by the effective control of rats

Sylvatic plague 

  • is difficult or impossible to eliminate
  • mammalian reservoirs and flea vectors are widespread
  • Y. pestis produces a fatal infection in the animal reservoir
  • infections can be acquired:
    • flea bite
    • ingestion of contaminated animals
    • handling of contaminated animal tissues
    • human-to-human - respiratory droplets
  • Clinical Diseases; two clinical manifestations:
  • Bubonic plague
    • incubation period 7 days
    • high fever and a painful bubo (inflmmatory swelling of the lymph nodes) in the groin or axilla
    • bacteremia develops - 75% die. 
  • Pneumonic plague
    • incubation period 2 to 3 days
    • fever and malaise pulmonary signs develop within 1 day


C3. C. Diphteria diseases.

LOCAL exotoxin effect:

  • harming the mucosal membrane, pseudomembrane formation (difficult to remove, gray-greenish; fibrin + dead leukocytes + red blood cells)

 DISTANT exotoxin effect:

  • organ failures (heart /myocarditis/, liver, kidney)
  • temporary paralysis of arms, legs, or eye muscles
  • slurred speech, double vision


C4. Rice-water like diarrhea, which bacteria?

Vibrio cholerae


C5. List bacteria that cause meningitis.



  • Streptococcus agalactiae (B-group)
  • Listeria monocytogenes
  • Haemophilus influenzae
  • E. coli
  • Staphylococcus aureus
  • Streptococcus pyogenes 
  • Streptococcus pneumoniae
  • Neisseria meningitidis
  • Campylobacter 


C6. List bacteria that are lactose positive.

  • Escherichia coli
  • Klebsiella
  • Enterobacter

Slow fermenters: 

  • Serratia


D1. Describe B. Pertusis (everything; morphology, cultivation, biochemical properties, etc.).

  • Obligate human pathogen

Morphology: Gram-negative, strict aerobic, 0.2x1µm coccobacillus


  • fastidious! -> Bordet-Gengou plate (10% blood, potato, glicerol)
  • 3-7 days, moist environment, mild haemolysis

Virulence factors:

  • Fimbria
  • Exotoxin 
    • tracheal citotoxin - inhibition of cilia movement
    • dermatonecrotic toxin - tissue destruction
    • pertussis toxin - increase cAMP
    • filamentous haemagglutinin - attachment to ciliated cells
    • pertactin - attachment to ciliated cells
    • adenylate cyclase - increase cAMP
  • endotoxin

Disease: whooping cough

  • airborne infection - by respiratory droplets
  • is very infectious - each primary case produces approximately 15 secondary cases
  • co-infection is very common

Vaccine: aP - A cellular pertussis (usually given with Diphtheria and Tetanus Toxoids as DTaP)


D2. List the causes for pneumonia.

  • Streptococcus pneumoniae
  • Staphylococcus aureus
  • Haemophilus influenzae
  • Legionella
  • Klebsiella



D3. E. coli diseases.

  • UTI
  • Neonatal meningitis


  • EPEC enteropathogenic E. coli dyspepsia coli - colitis of the newborns
  • ETEC enterotoxic E.coli - cholera like diarrhea, „traveler's disease"
  • EIEC enteroinvasive E. coli - dysentery
  • EHEC enterohaemorrhagic E.coli - dysenteriform diarrhea
  • EAEC 


D4. Describe special culture media and staining and the type of the appropriate bacteria.

Corynebacterium diphtheriae:


  • Clauberg:
    • Glicerin, Blood, Cystin and tellurite (Selective)
    • Reduce the tellurite to different extent 
      • Grey - Black
    • Garlic smell
    • Gravis, intermedius and mitis biotypes
  • Löffler:
    • Ivory color
    • Clotted bovine serum, egg, heart extract.
    • Rapid growth, strong volutin granule formation




  • Do not stain with common staining, needs silver stain to be visualized
  • Require media supplemented with L-cystein, and growth is enhanced by iron


D5. Hib vaccination.

Hemophilus influenzae type b vaccine- the polysaccharide capsule is conjugated to another bacteria or another immunogenic carrier, because it's not strong enough alone as an antigen, given between 2-18 months of age

(prevents meningitis caused by B serotype)


D6. One hour after eating ice cream the patient had diarrhea. Mediated diseases? Bacteria?

Staphylococcus aureus


E1. shigella dysenteria.

  • Causes dysentery
  • Produces Shiga-toxin
    • inhibition of protein synthesis
    • ulceration of large intestine
    • mainly by S. dysenteriae type I

Morphology: Gram-negative, facultative anaerobic, nonspore-forming, nonmotile, rod-shaped bacteria


  • lactose -, H2S -, uresae -


  • Hektoen Enteric Agar


  • First they infect the M cells (in the Peyer’s patches)
  • From here, they can infect the epithel cells from the side

  • They can go from M cells into macrophages

  • Being released from dead macrophages, they can infect the basal surface of the epithel cells

Clinical findings:

  • Incubation time: few days
  • First symptom: diarrhea
  • Fever, tenesmus (improductive)
  • Stool: blood, mucus, pus
  • Most severe disease: S. dysenteriae
    • toxin production!
  • Frequent complication: HUS (haemolytic uremic syndrome)
  • Outcome:
    • usually spontaneous recovery
    • might result carriage
    • reactive arthritis
  • Other dysentery causative agents:
    • bacterial: EIEC
    • protozoan: Entamoeba hystolytica


E2. Causes of impetigo.

  • Staphylococcus aureus
  • Streptococcus pyogenes


E3. Name exotoxin mediated diseases.

Strep progenes:

  • pyrogenic exotoxin-A - TSLS

  • pyrogenic exotoxin-B - necrotizing fasciitis (=protease)

Staphylococcus aureus:

  • TSST-1 (toxic shock syndrome toxin)
  • staphylococcal scalded skin syndrome (Ritter disease)

Bordatella pertussis:

  • tracheal toxin (blockage of mucociliary clearance → characteristic whooping cough)


E4. Content of DtaP.

Diphtheria and Tetanus toxoids and acellular Pertussis vaccine


E5. lactamase in the enterocococeae family.

ESBL (Extended spectrum beta-lactamases)

  • Often on plasmids (easy transfer to each other!), or chromosomal
  • „simple" ESBLs:
    • TEM, SHV, ...
    • Resistance to penicillins and cephalosporins
    • Klebsiella, E. coli
  • MBLs: (Metallo-beta lactamases)
    • Resistance to all β-lactams, including carbapenems !
    • Klebsiella, Pseudomonas, Acinetobacter

Treatment of Enterobacteriaceae infections

  • Always after antibiogram !!
  • ESBL production !!!
  • β-lactam + enzyme inhibitor combination
  • 3rd gen. cephalosporins
  • carbapenems
  • aminoglycosides
  • fluoroquinolones


E6. If x drunk non pasteurized milk + he complains of muscle pain, arthritis, fever what bacterium caused it?

Brucella genus


F?1. Describe S. Pyogenes




  • Gram-positive cocci, arranged in chains

Cultivation: fastidious!

  • small, pin-point colonies
  • strong β-hemolysis

Virulence factor:

  • Capsule made of hyaluronic acid (!)
  • M protein


F?2. Which diseases can be caused by Haemophilus group?

Capsulated strains (mainly b): invasive infections

  • meningitis (high mortality!)
  • respiratory tract infections (pneumonia, epiglottitis)
  • cellulitis

Non-capsulated (NT) strains:  milder upper RTI

  •  otitis media, sinusitis !!

Asymptomatic carriage!!


F?3. List the gram negative and urease positive.

  • Klebsiella
  • Helicobacter



F?4. Someone who travelled gets diarrhea (not bloody), Which bacteria might cause that

  • ETEC - Enterotoxigenic E. Coli
  • Vibrio choleara