Microbiology Flashcards

1
Q

Define pathogen

A

An organism that causes/can cause a disease

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2
Q

Define commensal

A

Organism colonising the host but usually causes no disease

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3
Q

Define opportunist pathogen

A

Microbe only causing disease if host diseases compromised

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4
Q

Define virulence/pathogenicity

A

Degree to which an organism is pathogenic

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5
Q

Define asymptomatic carriage

A

Pathogen carried harmlessly at a tissue site, causing no disease

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6
Q

How is a gram stain done (4 steps)?

A
  1. Add crystal violet
  2. Add iodine
  3. Add acetate/alcohol to decolourise
  4. Add sapranin counter stain
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7
Q

What colour will gram positive bacteria be after staining?

A

Retain crystal violet- PURPLE

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8
Q

What colour will gram negative be after staining?

A

Safranin stains PINK

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9
Q

What are 3 gram positive cocci?

A

Staphylococci
Streptococci
Enterococci

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10
Q

What are 3 gram positive bacilli?

A

Bacillus
Clostridia
Corynebacteria

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11
Q

Why are gram positive and gram negative different colours?

A

Gram-negative cells have a thinner peptidoglycan layer that allows the crystal violet to wash out on addition of ethanol. They are stained pink or red by the counterstain

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12
Q

What are 2 gram negative cocci?

A

Neisseria
Moraxella

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13
Q

What are 5 gram negative bacilli?

A

E. Coli
Campylobacter
Salmonella
Shingles
Proteus

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14
Q

What are 7 types of agar cultures?

A

Blood agar
Chocolate agar
Cled agar
MacConkey agar
XLD agar
Sabourard agar

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15
Q

How is chocolate agar made and why I it used?

A

Blood agar cooked at 80 degrees for 5 mins
-Nutrients are released

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16
Q

What type of microorganism are grown on MacConkey agar?

A

Only gram negative bacilli

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17
Q

Why is MacConkey agar used?

A

Differentiates lactose fermenting from non-lactose fermenting

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18
Q

What temperature can bacteria survive at?

A

-800 to 80 degrees
1200c for spores

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19
Q

What pH can bacteria survive at?

A

4-9

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20
Q

How long can bacteria survive in water?

A

2 hours-3 months
spores can live >50 years

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21
Q

Describe the structure of a bacterial cell?

A

Capsule- sugar polymer that can inhibit immune system
Cell wall- phospholipid membrane
Usually no nuclear membrane
1 circular chromosome

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22
Q

Describe the cytoplasmic membranes of gram positive and gram negative bacteria

A

Positive: single membrane
Negative: 2 membranes

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23
Q

Describe the peptidoglycan membranes of gram positive and negative bacteria

A

Gram positive: thick membrane
Gram negative: thin layer between the 2 cytoplasmic membranes

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24
Q

Where are lipoteichoic and teichoic acids present?

A

Gram positive

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25
Q

When is endotoxin present?

A

Gram negative

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26
Q

What is endotoxin?

A

Outer membrane of gram negative bacteria

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27
Q

What locations in the body are sterile?

A

Blood
CSF
Joints
Bladder
Lower resp tract
Pleural fluid
Peritoneal cavity

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28
Q

What locations in the body are colonised with flora?

A

GI tract
Skin
Oral cavity
Vagina
Urethra

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29
Q

How is bacterial growth rate measured?

A

Shining light and measuring absorption

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30
Q

What is exotoxin?

A

Proteins secreted from gram negative and gram positive bacteria
-mainly gram positive

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31
Q

Describe the antigenicity (binding to immune system) of endotoxin and exotoxin

A

Endotoxin: weak
Exotoxin: strong

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32
Q

Describe the specificity of endotoxin and exotoxin

A

Endotoxin: unspecific
Exotoxin: specific

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33
Q

Describe the heat specificity of endotoxin and exotoxin

A

Endotoxin: heat stable
Exotoxin: unstable

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34
Q

What can be converted to toxoid (non-active toxin)?

A

Endotoxin

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35
Q

What effect does botulism have?

A

Inhibits nervous system

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36
Q

What effect does tetanus have?

A

Stimulates nervous system

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37
Q

Describe the process of bacterial infection

A
  1. Th cell activation
  2. Th cells secrete INF + TNF and IL-2
  3. Macrophage recruitment
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38
Q

How does genetic variation occur on a chromosome?

A

Base substitution
Deletion
Insertion

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39
Q

What is a plasmid?

A

Small circular DNA
Antibiotic resistant genes

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40
Q

How are genes transferred by transformation?

A

Uptake of exogenous substance (ie plasmid) leads to genetic alteration of cell

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41
Q

How does gene transfer occur by transduction?

A

Foreign DNA introduced via vector/ virus

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42
Q

How does gene transfer occur via conjugation?

A

Direct cell to cell contact that transfers genetic material

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43
Q

Is staphylococcus aerobic or anaerobic?

A

Aerobic

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44
Q

What is the normal habitat of staphylococcus?

A

Skin and nose

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45
Q

What is coagulate?

A

Enzyme that forms fibrin clot around bacteria and protects from phagocytosis

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46
Q

How is staphylococcus aureus spread?

A

Aerosol and touch

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47
Q

Is staphylococcus aureus coagulase positive or negative?

A

Positive

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48
Q

How does staphylococcus aureus show on blood agar?

A

Creamy/yellow

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49
Q

What are the 4 virulence factors of staphylococcus aureus?

A

Pore forming toxins
Proteases
Toxic shock syndrome
Protein A

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50
Q

What does MRSA stand for?

A

Methicillin resistant staphylococcus aureus

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51
Q

What are some conditions associated with staphylococcus aureus?

A

TSS
Wound infections
Food poisoning
Scalded skin syndrome

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52
Q

What are 2 coagulate negative staphylococci?

A

Staphylococcus epidermis
Staphylococcus saprophyticus

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53
Q

What shape are staphylococcus aureus cells?

A

Spherical clusters

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54
Q

Is streptococcus catalase positive or negative?

A

Negative

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55
Q

Are staphylococcus and streptococcus gram positive or negative?

A

Positive

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56
Q

What are the 3 groups of streptococcus?

A

Alpha haemolytic
Beta haemolytic
Non haemolytic/ gamma haemolytic

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57
Q

What type of agar is streptococcus haemolysis done on?

A

Blood agar

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58
Q

How alpha haemolytic streptococci appear?

A

Partial lysis- green/browning

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59
Q

What is an example of an alpha haemolytic strep?

A

S. Oralis
S. Sanguis
S. Pneomonie

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60
Q

How does beta haemolytic strep present?

A

Complete lysis- colourless

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61
Q

What is an example of a beta haemolytic strep?

A

S. Pyogenes
S. Agalactiae

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62
Q

How does gamma haemolytic strep appear?

A

No lysis

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63
Q

What is an example of gamma/nom haemolytic strep?

A

S. Bovis
S. Mutans

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64
Q

Are enterococcus catalase positive or negative?

A

Negative

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65
Q

What is an example of enterococcus?

A

E. Faecalis

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66
Q

What is optochin sensitivity tested on?

A

Alpha haemolytic strep

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67
Q

What is an example of a optchin resistant strep?

A

Viridans strep

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68
Q

What is an example of an optochin sensitive strep?

A

S. Pneumoniae
-all other alpha strep are resistant

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69
Q

What is antigenic zero-grouping carried out on?

A

Beta haemolytic strep

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70
Q

What is zeihl-neelsen stain test used for?

A

Mycobacteria do not take up gram stain so this is used to identify acid-fast bacilli and non acid-fast bacilli

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71
Q

What colour will acid fast bacilli be?

A

Red

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72
Q

What colour will non-acid fast bacilli be?

A

Blue

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73
Q

What is catalase test used for?

A

Differentiating streptococci and staphylococci

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74
Q

What is catalase positive?

A

Staphylococci

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75
Q

What is catalase negative?

A

Streptococci

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76
Q

Why is a coagulase test used?

A

Coagulase produced by staph. Aureus
-distinguishes it from other staph

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77
Q

What indicates positive coagulase result?

A

Clumping

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78
Q

What generates a coagulase positive response?

A

Staphylococcus aureus

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79
Q

How are beta haemolytic bacteria differentiated?

A

Lancefield grouping

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80
Q

What is lancefield grouping A, C and G?

A

Tonsillitis and skin infection

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81
Q

What is lancefield grouping B?

A

Neonatal sepsis and meningitis

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82
Q

What is lancefield grouping D?

A

UTI- enterococci

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83
Q

What indicates optochin sensitivity?

A

Clear zone of no growth around disc

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84
Q

Are oxidase positive bacteria anaerobic or aerobic?

A

Aerobic

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85
Q

Are oxidase negative bacteria anaerobic or aerobic?

A

Either

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86
Q

What are some oxidative positive bacteria?

A

Campylobacter
Helicobacter
V. Cholerae

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87
Q

What indicates oxidase positivity?

A

Blue colour change

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88
Q

What does a pink/red colour on MacConkey agar indicate?

A

Lactose fermenting bacteria

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89
Q

What does a whit/transparent result show on MacConkey agar?

A

Non-lactose fermenting bacteria

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90
Q

Why is XLD agar used?

A

Differentiates salmonella and shingella

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91
Q

How does salmonella show on XLD agar?

A

Red/pink with black spots

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92
Q

How does shingella show on XLD agar?

A

Red/pink colonies

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93
Q

How are streptococci differentiated using lancefield typing?

A

Groups coagulase negative and positive bacteria
- group A and B

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94
Q

What is in strep group A?

A

Strep pyogenes

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95
Q

What is in strep group B?

A

Strep agalactiae

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96
Q

What are the common clinical presentations of staph aureus?

A

Pain in shoulder
High temperature
Osteomyelitis in C6 and 7

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97
Q

How much osteomyelitis is staph aureus responsible for?

A

90%

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98
Q

How is staph aureus treated?

A

Flucoxacillin for 3 months

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99
Q

Where does staph epidermis occur?

A

Prosthetic limbs and catheters

100
Q

What infections do strep pyogenes cause?

A

Wound infections
USUALLY tonsillitis and pharyngitis
Otitis media
Scarlet fever

101
Q

What are the complications of strep pyogenes?

A

Rheumatic fever
Glomerulnephritis
Scarlett fever

102
Q

What is the common presentation of strep pneumoniae?

A

Heavy smoker
Cough and severe chest pain for 2 days
Rust coloured sputum
Consolidation- lungs filled with fluid

103
Q

What infections does strep pneumonie cause?

A

Pneumonia
Otitis media
Sinusitis
Meningitis

104
Q

What are some predisposing factors for strep pneumoniae?

A

Impaired mucus trapping
Hypogammaglobulinemia
Asplenia
Diabetes
Renal disease
Sickle cell
Young age

105
Q

What is the collective name for oral streptococci?

A

Viridans streptococci

106
Q

What conditions are associated with Viridans strep?

A

Dental cavities and abscesses
Infective endocarditis
Deep organ abscesses

107
Q

What is the common presentation of corynebacterium diptheriae?

A

Child with sore throat
2 days fever and malaise
Lymphadenopathy in neck
Rapid breathing
Grey membrane on tonsils

108
Q

What will the swab show for corynebacterium diphtheriae?

A

Gram positive bacilli (rods)

109
Q

How is corynebacterium diptheriae treated?

A

Antitoxin
Erythromycin

110
Q

Why do gram negative find secreting a toxin more difficult than gram positive bacteria?

A

Toxin has to cross 2 membranes instead of just one

111
Q

What infections are caused by E.coli?

A

Wound infections
UTI
Gastroenteritis
Travellers diarrhoea
Meningitis in infants

112
Q

What is the MC species of shingella?

A

S. Sonnei

113
Q

What does shingella damage to intestinal mucosa lead to?

A

Acute infection of large intestine
Painful diarrhoea with blood and mucus

114
Q

How is shingella spread?

A

Contaminated water or food

115
Q

What is the infective dose for shingella?

A

100 bacteria- very easy to be infected

116
Q

What are the common properties of enterobacteria ?

A

Rod shaped
Mostly motile
Anaerobic

117
Q

What are the common properties of shingella?

A

Non lactose
Non motile

118
Q

What are the 2 types of salmonella?

A

S. Enterica
S. Bongori

119
Q

What causes s. Bongori?

A

Rare- reptile contact

120
Q

What is S. enterica responsible for?

A

Salmonellosis- infection caused by salmonella

121
Q

What are infections caused by salmonella?

A

Gastroenteritis
Typhoid
Bacteraemia

122
Q

What is the usual cause of food poisoning from milk and poultry?

A

Gastroenteritis

123
Q

Is gastroenteritis localised or systemic?

A

Localised

124
Q

Is typhoid systemic or localised?

A

Systemic

125
Q

What causes typhoid?

A

Salmonella typhi and paratyphi

126
Q

How is typhoid spread?

A

Faeco-orally

127
Q

How does shingella cause infection?

A
  1. Uptake to basolateral side of M cell
  2. Macrophage phagocytoses
  3. Induced apoptosis
  4. Shigella moves laterally through cells destroying gut
  5. Dying macrophage releases pro-inflammatory signals (cytokines)
  6. Attracts leukocytes causing inflammation
128
Q

What is bacteraemia?

A

Presence of bacteria in the blood

129
Q

How does enteric fever occur?

A
  1. Dissemination via macrophages -> lymph nodes
  2. Enters bloodstream ->LIVER, SPLEEN, MARROW
  3. Proliferate and released from macrophage-> bacteraemia
  4. Organs affected = symptomatic
  5. Colonises gallbladder -> small intestine
  6. Produces typhoid toxin
130
Q

What signs of enteric fever can be seen in s.intestine?

A

Inflammation and ulceration of payers patches

131
Q

How can proteus mirabilis cause kidney and bladder stones?

A

Urease production -> ph increase -> calcium phosphate precipitation -> stones

132
Q

What is the most common cause of proteus miribalis contraction?

A

Catheter UTI

133
Q

Describe the structure of vibrio cholerae

A

Curved rods with single polar flagellum

134
Q

How is vibrio cholerae transmitted?

A

Faeco-orally

135
Q

Why is a high infective dose required for vibrio cholerae?

A

Sensitive to acid- hard to get past stomach

136
Q

What are the effects of vibrio cholerae?

A

Watery diarrhoea- Up to 20L lost/day
-dehydration
-50-60% mortality if untreated

137
Q

How is vibrio cholerae treated?

A

Oral rehydration

138
Q

Describe the structure of pseudomonas aeruginosa

A

Rod shaped motile with single flagella

139
Q

What infections can be caused by pseudomonas aerugionsa?

A

Localised: wounds, UTI, keratitis
Systemic: neutropenic patients (chemo, HIV,ect)
ICU: pneumonia

140
Q

Does haemophilius influenzae cause flu?

A

No

141
Q

What infections can be caused by haemophilius influenzae?

A

MENINGITIS
Bronchopneumonia
Bacteraemia
Epiglottitis ect

142
Q

What are 2 types of beta-proteobacteria?

A

Neisseria
Bordetella pertussis

143
Q

Who are Haemophilus influenzae infections usually seen in?

A

Young children
Adult smokers

144
Q

What does legionella pneumophilia cause?

A

Legionnaires disease
-Pneumonia

145
Q

Where does legionella pneumophilia grow?

A

Man-made aquatic environment
-parasite in amoeba

146
Q

Where in the body does legionella pneumophilia grow?

A

Lives and replicates in alveolar macrophages

147
Q

What does bordetella pertussis cause?

A

Pertussis= whooping cough

148
Q

How is whooping cough spread?

A

Aerosol
- very infectious = low infective dose

149
Q

What can whooping cough cause?

A

Sub-conjunctival haemorrhage

150
Q

What are the symptoms of whooping cough?

A

Non-specific flu-like symptoms
Paroxysmal coughing (cough followed by inhalation resulting in whooping sound)

151
Q

What is the structure of Neisseria?

A

Diplodocci- travel in pairs

152
Q

What are the 2 species of Neisseria?

A

N. Meningitidis
N. Gonorrhoea

153
Q

How is N.meningitidis spread?

A

Person-to-person aerosol
-Common in barracks and student halls

154
Q

What diseases can be caused by N. Meningitidis?

A

Can cross nasopharyngeal epithelium -> blood stream

-Asymptomatic bacteraemia
-Meningitis
-Septicaemia VERY HIGH MORTALITY

155
Q

What are the virulence determinants of N. Meningitidis?

A

Capsule anti-phagocytosis
Pilli promote invasion

156
Q

How is N. Gonorrhoea spread?

A

Perso to person sexual contact

157
Q

What conditions can N. Gonorrhoea cause?

A

Urethritis
Infection of Fallopian tubes
Can be asymptomatic in 30-50%

158
Q

What is the most common cause of food poisoning in the UK and USA?

A

Campylobacter

159
Q

What are the causes of campylobacter?

A

Undercooked poultry
Unpasteurised milk

160
Q

What are the effects of campylobacter?

A

Mild-severe diarrhoea with blood
Usually self limiting within a week

161
Q

How common is helicobacter pylori?

A

Present in 50% of global population

162
Q

How does helicobacter pylori protect itself?

A

Uses urea -> ammonia -> neutralises stomach acid

163
Q

What are infections commonly caused by helicobacter pylori?

A

Gastritis
Peptic ulcer disease
- gastric cancer

164
Q

What is the most common STI?

A

Chlamydia trachomatis

165
Q

What are the 2 phases of chlamydia growth?

A
  1. Elementary bodies- dormant
    -infects cell and prevents phagocytosis
  2. Reticulate bodies- metabolically active
    -replicative and non-infectious
166
Q

What diseases can chlamydia cause?

A

Usually asymptomatic
Uterus and ovaries - pelvic inflammatory disease
Can cause conjunctivitis
Can cause trachoma - blindness

167
Q

How do staphylococci appear under the microscope?

A

Clusters

168
Q

How does streptococcus appear under the microscope?

A

Chains

169
Q

Define acute diarrhoea

A

Lasts <2 weeks

170
Q

Define chronic diarrhoea

A

> 4 weeks

171
Q

What are the 2 categories of acute diarrhoea?

A

Non-inflammatory (watery)
Inflammatory/ dysentery (bloody)

172
Q

What are the 2 ways that pathogens can cause diarrhoea?

A

Secrete endotoxins directly into food
Enter the body and distrust intestinal homeostasis via enterotoxins

173
Q

What are 2 pathogens that can cause non inflammatory diarrhoea?

A

ETEC
Vibrio cholerae

174
Q

What are 2 pathogens that can cause inflammatory diarrhoea?

A

Salmonella
Shingella
Campylobacter
C. Difficile

175
Q

What are the risk factors of diarrhoea?

A

PPI use
Recent travel to developing countries
Abx treatment
Immunosupression

176
Q

What pathogen is associated with reheating rice?

A

Bacillus cereus

177
Q

What is the MC cause of travellers diarrhoea?

A

ETEC

178
Q

How is ETEC diarrhoea treated?

A

Ciprofloxacin

179
Q

What pathogen is associated with cruise ships and care homes?

A

Norovirus

180
Q

What is a cause of long lasting diarrhoea?

A

Giardia lamblia

181
Q

How is giardia lamblia treated?

A

Metronidazole

182
Q

How are shingella and salmonella treated?

A

Ciprofloxacin

183
Q

How is C. Difficile treated?

A

Vancomycin

184
Q

What is c. Difficile associated with?

A

Antibiotic use

185
Q

What layers does cellulitis involve?

A

Deeper dermis and subcutaneous fat

186
Q

When does cellulitis occur?

A

Following a break in normal skin integrity

187
Q

What are the MC sites of cellulitis?

A

Legs
Face
Arms

188
Q

What are 2 causes of cellulitis?

A

Beta haemolytic strep
- s. Pyrogenes and s. Agalactiae
Staph aureus

189
Q

What are the risk factors of cellulitis?

A

Skin wounds
Diabetes
Bites
Elderly
Swollen legs

190
Q

What are the symptoms of cellulitis?

A

“Tracking” erythema
Pain, warmth and swelling
Associated wound

191
Q

How is cellulitis treated?

A

Elevate and mobilise limb
Flucoxacillin or clindamycin

192
Q

Define necrotising fasciitis

A

Necrotising infection of deep structures of the skin and underlying fascia

193
Q

What causes necrotising fasciitis?

A

Break in the skin causes infection of fascia -> thrombosis of adjacent tissue -> necrosis and anaesthesia of more superficial layers

194
Q

What causes type 1 necrotising fasciitis?

A

Aerobic and anaerobic organisms

195
Q

What is the MC cause of type 2 necrotising fasciitis?

A

Strep pyogenes

196
Q

What are the symptoms of necrotising fasciitis?

A

Erythema, warmth and tenderness
Quickly spreading blue grey colouring and loss of sensation
Crepitus (joint crunching)

197
Q

Define debridement

A

removal of dead, damaged, or infected tissue

198
Q

How is necrotising fasciitis treated?

A

Surgical exploration and debridement
Piperacillin + clindamycin

199
Q

How is strep pyogenes treated?

A

amoxicillin

200
Q

What is the MC cause of osteomyelitis?

A

Staph aureus

201
Q

What is the MC cause of osteomyelitis in IVD users?

A

Pseudomonas
E. Coli

202
Q

What is the MC cause of osteomyelitis in hip/knee replacement patients?

A

Staph epidermidis

203
Q

How is osteomyelitis treated?

A

Surgical debridement
Flucloxacillin and fusidic acid

204
Q

What is the MC cause of septic arthritis?

A

Staph aureus

205
Q

How is N.gonorrhoea treated?

A

Ceftriaxone

206
Q

How is c. Trachomatis (chlamydia) treated?

A

Doxycycline or azithromycin

207
Q

What is protective against malaria?

A

Sickle cell trait (HbS)

208
Q

What is the MC cause of malaria?

A

F. Falciparum

209
Q

Define antimicrobial agent

A

Substance with inhibitory properties against microorganisms but minimal effects on mammalian cell

210
Q

Define antibiotic

A

Substance produced by microorganisms that inhibit or kill the growth of other bacteria

211
Q

Define empirical therapy

A

Antimicrobial regimen used when there is a delay in initiating therapy but there is a clinical diagnosis of infection

212
Q

Define directed therapy

A

Directed antimicrobial regimens are prescribed to target a specific pathogen

213
Q

Define antibiotic resistance

A

Ability of a microorganism to avoid the harmful evens of an antimicrobial by destroying it, removing it or blocking its effects

214
Q

Define antibiotic susceptiblity

A

Level of vulnerability of a microorganism to an antimicrobial

215
Q

What are 2 types of antibiotics that inhibit cell wall synthesis?

A

Beta-lactams
Glycopeptides

216
Q

What are 3 types of beta lactams?

A

Penicillins
Cephalosporins
Carbapenems

217
Q

What are 3 types of penicillins?

A

Benzylpenicillin
Flucoxacillin
Ampicillin/amoxicillin

218
Q

What is benxylpenicillin used to treat?

A

Strep
Pneumonia
Meningitis

219
Q

What is Flucoxacillin used to treat?

A

Staph aureus

220
Q

What is amoxicillin used to treat?

A

UTI
listeria
Enterococci

221
Q

What is a 1st gen cephalosporin?

A

Cephalexin

222
Q

What is a 2nd generation cephalosporin?

A

Cefuroxime

223
Q

What is a 3rd generation cephalosporin?

A

Ceftazidime

224
Q

What are cephalosporins used to treat?

A

Strep
Nisseriere

225
Q

What are 2 carbapenems?

A

Imipenem
Ertapenem

226
Q

What are carbapenems used to treat?

A

Enterobacteria

227
Q

When are carbapenems contraindicated?

A

Breastfeeding

228
Q

What are 4 ways antibiotics can inhibit nucleic acid synthesis?

A

Inhibiting folate synthesis
Inhibits DNA gyrase
Binding to RNA polymerase
Breaking DNA strands

229
Q

What are 3 antibiotics that inhibit folate synthesis?

A

Trimethoprim
Sulfamethozazole
Co-trimoxazole (both)

230
Q

What is trimethoprim used to treat?

A

UTI

231
Q

When is trimethoprim contraindicated?

A

pregnancy
- interferes with folate = spina bifida

232
Q

What is co-trimoxazole used to treat?

A

PCP (pneumonia)

233
Q

How do fluoroquinolones (eg. Ciprofloxacin) work?

A

Inhibit DNA gyrase

234
Q

How does Rifampicin work?

A

binds to RNA polymerase

235
Q

How does metronidazole work?

A

Breaks DNA strands

236
Q

What is metrinidazole used to treat?

A

Parasites eg giardia lamblia

237
Q

What are 4 types of antibiotics that inhibit protein synthesis?

A

Chlormaphenicol
Macrolides
Tetracyclines
Aminoglycosides

238
Q

When is chloramphenicol contraindicated?

A

Pregnancy
Breast feeding

  • Grey baby syndrome
239
Q

What type of antibiotics are clarithromycin and erythromycin?

A

Macrolides

240
Q

What are 2 tetracyclines?

A

Tetracycline
Doxycycline

241
Q

What type of drug are gentamycin and streptomycin?

A

Aminoglycosides

242
Q

What is used to treat severe sepsis?

A

Gentamycin

243
Q

When are tetracyclines contraindicated?

A

Children <12

244
Q

What are 2 lactose fermenting bacteria?

A

CEEK

Citrobacter
Enterobacter
E.Coli
Klebsiella

245
Q

What is an example of a non motile non lactose fermenting bacteria?

A

Shingella

246
Q

What are 2 motile non lactose fermenting bacteria?

A

Proteus
Salmonella

247
Q

How is strep viridians treated?

A

Benzylpenicillin + gentamycin