Week 6 - Microorganisms Flashcards

Question

Clostridium difficile

Answer 1

Gram positive Bacilli anaerobe spores survive alcohol and temp/drying out Enterotoxin -diarrhoea and cell death of colonic epithelium by digesting connective tissue Severe watery diarrhea Major cause of healthcare associated infection (HAI)

Answer 2

``` Gram positive Bacilli anaerobe alpha toxin - enzyme which causes lysis gas gangrene and other soft tissue infections food poisoning ```

Answer 3

Causes rocky mountain spotted fever NOT RICKETS | Don't take up gram stain

Answer 4

``` Fastidious = difficult to grow in the laboratory Gram negative Bacilli aerobe water-bourne legionnaire's and pontiac fever Atypical pneumonia ```

Answer 5

``` Don't take up gram stain Resistant to many antibiotics Lack of cell wall Limited metabolic activity Replicate intracellularly Cannot be cultured by standard methods ```

Answer 6

``` Don't take up gram stain Resistant to many antibiotics Lack of cell wall Limited metabolic activity Replicate intracellularly Cannot be cultured by standard methods Atypical pneumonia ```

Answer 7

Gram-negative cocci commensal Facultative anaerobe meningitis, bacteraemia and pneumonia

Answer 8

Gram-negative cocci Facultative anaerobe Transmitted through sexual contact or mother to infant (perinatally) Localized – urethritis, cervicitis, conjunctivitis Pelvis inflammatory disease Concerns of drug resistance

Answer 9

Gram-negative cocci Facultative anaerobe Common commensal of the human upper respiratory tract (esp infants) Opportunistic pathogen Children- otitis media Adults – lower respiratory tract infection in chronic obstructive pulmonary disease (COPD) More than 90% produce β-lactamase – amoxicillin resistant

Answer 10

clusters (obviously) gamma haemolysis coagulase negative catheters - UTIs

Answer 11

clusters (obviously) gamma haemolysis coagulase negative catheters - UTIs vancomycin

Answer 12

clusters (obviously) coagulase negative prosthetic heart valves -endocarditis

Answer 13

alpha haemolytic | gram positive

Answer 14

``` Beta haemolytic (group B gram positive ```

Answer 15

``` Beta haemolytic (group C gram positive ```

Answer 16

``` Beta haemolytic (group D gram positive endocarditis ```

Answer 17

Gram positive bacilli In soil Multiple toxins and virulence factors – high mortality Infected by cutaneous inoculation (IVDU) or inhalation

Answer 18

Gram positive bacilli faculative exotoxin inhibits protein synthesis causes diptheria - throat swelling - bull necking

Answer 19

aka lipoglycans and endotoxins in the walls of gram negative bacteria activate immune response leading to fever

Answer 20

Enterobacteriaceae - sugar fermentors, non-spore forming, motile by polar flagella, fimbriae for adhesion gram negative bacilli ``` Commonly found in the human gut Diarrhoeal illness UTI • Lower urinary tract infection • Upper UTI (ascending to kidneys) - pyelonephritis ```

Answer 21

Enterobacteriaceae - sugar fermentors, non-spore forming, motile by polar flagella, fimbriae for adhesion gram negative bacilli ``` • UTI • Liver abscess • Bacteraemia • Pneumonia Important in hospitals due to antibiotic resistance ```

Answer 22

Enterobacteriaceae - sugar fermentors, non-spore forming, motile by polar flagella, fimbriae for adhesion gram negative bacilli * Gastroenteritis * Typhoid fever * bacteraemia

Answer 23

Enterobacteriaceae - sugar fermentors, non-spore forming, motile by polar flagella, fimbriae for adhesion gram negative bacilli Found in unclean water and contaminated food – can be transmitted sexually Causes dysentery Infective dose is small (10-200) Major health threat in developing countries

Answer 24

Gram negative bacilli non-fermentor Microaerophilic – grows in the presence of oxygen at lower concentrations than atmospheric (usually around 2-10%) Food poisoning Raw and undercooked meat, unpasteurised milk

Answer 25

``` Gram negative bacilli Grows aerobically non-fermentor Opportunistic pathogen Innate resistance to many antibiotics Produces pigments ```

Answer 26

gram negative bacilli Grows aerobically non-fermentor Vibrio cholerae – hyperactivation of cell through exotoxin - diarrhoea - rice water stool

Answer 27

gram negative bacilli facultative fastidious Growth at ~5% CO2 Chocolate agar plate (heat-lysed horse blood) Absolute requirement for NAD (factor V) and a source of haem (factor X) Pneumonia, meningitis, otitis media

Answer 28

M. tuberculosis currently causes over 1.8 million deaths a year Primarily disease of lung, may spread to other sites e.g. miliary TB. in high risk groups Multidrug resistance and drug tolerance Thick, waxy cell wall (containing mycolic acid) ACID FAST BACILLI – resistant to decolourisation with acidified organic solvents (acid alcohol) Slow growth rate in culture (average 4 wks, up to 8 wks)

Answer 29

``` gram positive bacilli facultative no soft cheese or coleslaw during pregnancy neonatal meningitis/septicaemia inauterine meningitis/septicaemia ```

Answer 30

NOT ENTEROBACTERIACEAE | gram positive cocci

Answer 31

gram negative bacilli anaerobes resistant to penicillin

Answer 32

organisms which live in the environment

Answer 33

extracellular - capsules, anti-phagocytotic mechanisms | intracellular - being inside phagocytes or other cells

Answer 34

a protein toxin excreted by the organism

Answer 35

LPS - lipopolysaccharide activates endothelial cells, mast cells, platelets, clotting, complement, macrophages, TNF and Interleukin Fever, Distributive Shock, Disseminated intravascular coagulation (DIC), Hypoglycaemia

Answer 36

treatment of anaerobic bacteria