Microbiology

Question 1

What causes strawberry appearance of the cervix?

Answer 1

Trichomonoiasis

Question 2

Which STI causes extravasation of urine into the urethra?

Answer 2

Gonorrhoea

Question 3

What is a chancre?

Answer 3

Ulcer seen on the penis in primary syphillis

Question 4

Treatment for gonorrohea

Answer 4

IM ceftriaxone + PO azithromycin

Question 5

Treatment for chlamydia

Answer 5

PO doxycyline 100mg BD 7 days

Question 6

Treatment for trichomoniasis

Answer 6

Metronidazole

Question 7

Treatment for candidiasis

Answer 7

Fluconazole

Question 8

What pathogen causes syphillis?

Answer 8

Treponema pallidum

Question 9

Gonorrhoea

Answer 9

Gram -ve intracellular coccus - resists neutro killing
Asx in females
Males - golden pus formation

culture bacteria from urethral/cervical swab or PCR on 1st morning void

Question 10

Chlamydia

Answer 10

Very simple smal bacterium - obligate intracellular multiplication
Serotype D-K = GU
Serotype A-C = trachoma (eyelids)

PCR on 1st voided urine

Question 11

Trichomoniasis symptoms

Answer 11

Females - green/itchy/frothy discharge, vulval itch, offensive odour, abdo pain, strawberry cervix

Males = asx or discharge + dysuria

Question 12

Syphillis

Answer 12

Primary - affects genitals + causes painless ulcers that dissapear in 3-4wks if ignored.. spreads

secondary - affects hands where see painless rashes on palms, if ignored.. spread

tertiary - neurosyphillis resulting in peripheral neuropathy and destruction of dorsal columns - paralysis + personality effects

Question 13

Urethral sx of UTI

Answer 13

Burning, stinging at meatus, desire to micturate/frequency, dysuria

Question 14

Bladder sx of UTI

Answer 14

suprapubic heaviness/tenderness

Question 15

Pyelonephritis sx

Answer 15

Unilateral loin pain, rigors, bacteraemia, pyrexia, leucocytosis

Question 16

Uncomplicated UTI organisms

Answer 16

E coli (80%)
Streptococci
Chlamydiae
Proteus mirabilis

Question 17

Complicated UTI organisms

Answer 17

E coli (20%)
Klebsiella
Pseudomonas

Question 18

Tx for UTI

Answer 18

Simple - trimethoprim/nitrofurantoin

Pylenophretis - ciprofloxacin/co-amoxiclav

Question 19

Gram positive bacteria

Answer 19

Stain purple with gram stain
Simple cell wall but thick peptidoglycan layer

Streptococcus, staphylococcus, bacillus, clostridium, listeria

Question 20

Staph aureus

Answer 20

Gram +ve, golden colonies under microscope (cluster of grapes)

Question 21

Strep pyogenes

Answer 21

Gram +ve cocci, ability to lyse RBCs

Question 22

Gram negative bacteria

Answer 22

Stain pink with gram stain
Complex cell wall

E.coli, neisseria gonorrhoea, helicobacter

Question 23

Impetigo

Answer 23

Epidermis infection
Golden crusts over erythematous skin
Staph aureus
Flucloxacillin

Question 24

Folliculitis

Answer 24

infection of hair follicles
Staph aureus
Fluclox

Question 25

Furunculosis

Answer 25

Deep inflam lesion progressing from a folliculitis | Fluclox

Question 26

Carbuncle

Answer 26

Extends into subcut later of skin + develops multiple abscesses that are separated by connective tissue Fluclox

Question 27

Acute paronchia

Answer 27

Skin infection arising from nail | Fluclox

Question 28

Cellulitis

Answer 28

Acute, spreading inflammation of lower dermis + associated subcut layer of skin Commonly staph aureus Oral pen V and flucloxacillin

Question 29

Necrotising fasciitis

Answer 29

Bacteria enter fascial plane following trauma - causing inflammatory response 3 stages: Early - skin trauma with pain, flu like sx, thirst Advanced - swelling, large violet blotches, mottled flaky appearance Critical - hypoTN, toxic shock, unconscious

Question 30

Gas gangrene

Answer 30

Clostridium perfringens - produces toxins causing tissue death More common in underlying BV disease, DM or CRC

Question 31

Surgical site infections

Answer 31

20% of nosocomial infections | Must occur within 30d or 1yr if implant

Question 32

Acute osteomyelitis

Answer 32

Infection of bone following trauma, surgery or haematogenous route Can be acute or chronic Flucloxacillin 4-6wks if acute, 12wks if chronic

Question 33

What are the main components of bacteria that abx target?

Answer 33

Cell wall - beta lactams, glycopeptides Protein synthesis - tetracyclines, aminoglycosides, macrolides Folate synthesis - sulphonamides DNA synthesis - quinolones or metronidazole

Question 34

Symptoms of typical CAP

Answer 34

Fever, purulent sputum production, chest pain

Question 35

Symptoms of atypical CAP

Answer 35

Dyspnoea, cough, minimal sputum production, systemic upset

Question 36

Infections of the epidermis

Answer 36

Folliculitis Impetigo Furuncolosis

Question 37

Infections of the dermis

Answer 37

Carbunculosis

Question 38

Infections of the subcutaneous layer

Answer 38

Cellulitis | Necrotising fasciitis