Microbiology

Question 1

Features of actinomycosis

Answer 1

Gram positive bacilli
Faculative anaerobes
Can cause multiple abcesses
May develop in appendix
Direct visualisation of organisms and sulphur granules from lesions themselves is the easiest way to make a diagnosis.

Question 2

Diarrhoea with HIV

Answer 2

Cryptosporidium

Question 3

Large tonsils, petechial haemorrhages, splenomegaly and test diagnosis

Answer 3

EBV

Monospot test

Question 4

Organism causing genitourinary infection

Answer 4

E coli

Question 5

Boy with recurrent pruitius ani, small worm organism

Answer 5

Enterobius vermicularis

Question 6

Organism in septic arthritis for young adults

Answer 6

Neisseria gon

Question 7

Necrotising fasciitis

Answer 7

Mainly polymicrobial
Further surgery 24-48hrs after initial surgery to review extension of infection
Muscles are relatively spared
Crepitus in 35%

Strep most common in isolation
Risk in diabetes

Question 8

Floating stools and diarrhoea

Answer 8

Giardia lambilla

Question 9

Causes of osteomyelitis in sickle

Answer 9

Salmonella

Question 10

Features of salmonella type

Answer 10

Relative Brady
Rose spots on trunk
Constipation

Question 11

What is the risk of wound infection in a laparoscopic cholecystectomy for uncomplicated biliary colic

Answer 11

4%

Question 12

MOA of antibiotics

Answer 12

Cell wall- pen, ceph

Protein synthesis clindamycin 50, Oxala 50, amino 30, tetracycline 30, macrolides 50, linezolid 50

DNA synthesis- quinolones (cipro) dna gyrase, metronidazole, trimethoprim,

RNA- rifampicin

Question 13

Hard painless ulcer cause

Answer 13

Treponema pallidum

Question 14

Causes of Fourniers gangrene

Answer 14

E coli and bacteriodes

Question 15

What is the risk of a wound infection in a male undergoing a Hartmanns procedure for perforated sigmoid diverticular disease?

Answer 15

35%

Question 16

What is the likely risk of surgical wound infection in a 23 year old male undergoing an elective inguinal hernia repair?

Answer 16

Less than 5%

Question 17

Abx for MSRA

Answer 17

vancomycin
teicoplanin

Some strains may be sensitive to the antibiotics listed below but they should not generally be used alone because resistance may develop:
rifampicin
macrolides
tetracyclines
aminoglycosides
clindamycin

Question 18

Hepatits DNA/RNA

Answer 18

All RNA apart from Hep b which is double stranded DNA

Question 19

Malignant otitis externa organism

Answer 19

Pseudomonas aeruginosa

Question 20

Watercress, severe abdominal pain, fevers and progressive jaundice. Imaging with ultrasound shows mildly dilated bile ducts with hyperechoic areas

Answer 20

Fasciola hepatica

Treatment is with triclabendazole. Some patients may need ERCP

Question 21

C jejuni features

Answer 21

Most common cause of acute infective diarrhoea
Spiral, gram negative rods
Usually infects caecum and terminal ileum. Local lymphadenopathy is common
May mimic appendicitis as it has marked right iliac fossa pain
Reactive arthritis is seen in 1-2% of cases

Question 22

Diarrhoea, cyst on stool, immunocomprimsied

Answer 22

Cryptosporidium

Question 23

Mx of infected prosthesis

Answer 23

Removal of metal work implantation of gentamicin beads and delayed revision is the mainstay of managing this complication after 4 weeks. In earlier infections, linear exchanges covered by prolonged courses of antibiotics can be used.

Question 24

Cause of melanosis coli

Answer 24

Laxative abuse

Question 25

Organism causing severe peiritoneal infections

Answer 25

Bacteriodes

Question 26

Recently away, diarrhoea, with eggs and worms in stool

Answer 26

Ascaris lumbricoides

Question 27

Enterobiasis diagnosis

Answer 27

Common cause of pruritus ani Diagnosis usually made by placing scotch tape at the anus, this will trap eggs that can then be viewed microscopically

Question 28

Most common organism in infective endocarditis with prev faulty heart valves e.g rheumatic fever

Answer 28

Strep viridans

Question 29

Cause of quinsy

Answer 29

Strep pyogenes

Question 30

Spillage in cholecystectomy, now has diarrhoea cause?

Answer 30

Broad IV abc must have been given Causing C diff

Question 31

Children 6m to 4y cause of disci tis

Answer 31

Kigella Kigae If younger staph aureus

Question 32

E coli 0157 causes

Answer 32

Haemolytic uraemia syndrome in children Plasmids- antibiotic resistance

Question 33

Organism associate with septicaemia with carcinoma of colon

Answer 33

Strep bovis

Question 34

Severe abdo pain with diarrhoea lasting 18hrs

Answer 34

Campylobacter

Question 35

Pyrexia, diarrhoea, similar symptoms to appendicities- lap terminal ileum engoraged

Answer 35

Yersinia enterocolitica

Question 36

Tx of Yersinia

Answer 36

Usually sensitive to quinolone or tetracyclines

Question 37

Organism causing bladder calcification

Answer 37

Schistosoma haematobium

Question 38

Tx of shisto

Answer 38

praziquantel

Question 39

Organism infecting plastic devices

Answer 39

Staph epidermis

Question 40

Bloody diarrhoea, necrosis and ulcer of large bowel

Answer 40

Enteroinvasive E coli

Question 41

Testing for HIV

Answer 41

HIV antibody test most common and accurate test usually consists of both a screening ELISA (Enzyme Linked Immuno-Sorbent Assay) test and a confirmatory Western Blot Assay most people develop antibodies to HIV at 4-6 weeks but 99% do by 3 months p24 antigen usually positive from about 1 week to 3 - 4 weeks after infection with HIV

Question 42

Tx of C diff

Answer 42

Oral met or vac Severe- IV met and oral vanc

Question 43

Which ABx predispose to C diff

Answer 43

Cipro, cef NOT CLIND

Question 44

Time in autoclave and test after

Answer 44

3-15 mins Bowie Dick

Question 45

Bacterial parotitis

Answer 45

Staph aureus

Question 46

Vaccine pre and post splenectomy

Answer 46

4-6 w before every 5 years after

Question 47

Surgical oder with patient who is MRSA +

Answer 47

Put at the end of the list

Question 48

HDU vs ITU

Answer 48

HDU- single organ ITU- multiple or resp

Question 49

CD4 of HIV at risk of opportunistic infection

Answer 49

<200

Question 50

Organism causing balanitis

Answer 50

Candida

Question 51

Sickle cell, osteomyelitis

Answer 51

Salmonella

Question 52

What does diathermy increase the risk of

Answer 52

Infection in abdominal Surgery

Question 53

Proteus gram

Answer 53

Negative rod

Question 54

Enterococcus gram

Answer 54

Posotive coccus

Question 55

Pneumonia immunocomprimised, abcess

Answer 55

N asteroids

Question 56

Superficial vs deep abcess organism

Answer 56

Superficial- stap, step pyogenes Deep- neg and anaerobes

Question 57

Differentiating gram positive organisms

Answer 57

Cocci Staph (catalase +) Coagulase +- stap aureus Neg- epidermis, sapro Strep (catalase -) B haem (clear) pyogene, agalactiae y haem- enterococcus a haem (green)- pneumonia, viridans

Question 58

Co receptor for HIV into T cells

Answer 58

CCR5

Question 59

Hepatitis DNA vs RNA

Answer 59

All single RNA apart from Hep B which is double DNA

Question 60

Most common cause of post splenectomy sepsis

Answer 60

S pneumonia

Question 61

What can interferons induce

Answer 61

Apoptosis

Question 62

Organism of Quinsy

Answer 62

S pyogenes

Question 63

Cause of epipymal orchitis in children

Answer 63

E coli

Question 64

Needstick disease that is a notifiable disease

Answer 64

Hepatitis

Question 65

Toxin produced in HUS

Answer 65

Verotoxin

Question 66

Liver abcess in UK

Answer 66

Gram negative- either E coli or kleb

Question 67

Jaunfice after tonsillitis

Answer 67

EBV

Question 68

Toxin produced by staph

Answer 68

Haemolysis

Question 69

Abdo pain, poorly compliant HIV

Answer 69

Cytomegalovirus

Question 70

Endotoxin effect on the heart

Answer 70

Negative inoptropes

Question 71

Non bloody diarrhoea HIV

Answer 71

Cryptosporidium

Question 72

Spore baring bacteria

Answer 72

Baccilus and clostridium

Question 73

Where botulism acts

Answer 73

NMJ

Question 74

MOA of chlorhexidine

Answer 74

Disruption of cell membrane