Clinical Orientated Microbiology

Question 1

Clinical vs clinical and laboratory diagnosis?

Answer 1

clinical - possibly chickenpox is visible and can be diagnosed there and then

laboratory - need to combine the laboratory results and your knowledge of disease to clinically diagnose someone

Question 2

What are the 2 specimen types?

Answer 2

sterile and non-sterile sites

Question 3

What are the sterile sites?

Answer 3

brain
bone
pancreas
kidneys
liver

Question 4

What are the non-sterile sites?

Answer 4

skin
stomach and intestines
mouth and teeth
nose and airways
genital

Question 5

What is the difference between sterile and non-sterile body sites?

Answer 5

Non-sterile sites are usually those parts of the body that are exposed to the external environment and may contain microorganisms.

Question 6

Name 8 common specimen types of bacterial cultures?

Common infections which are tested for

Answer 6

• Urinary tract infection
• Chest infection
  *Tonsillitis/pharyngitis
• Wound / abscess
• Infectious diarrhoea
• Bacteraemia (sepsis)
• Meningitis
• Oral infections

Question 7

What specimen you you take a sample of to test for a UTI?

Answer 7

mid-stream urine

Question 8

What specimen you you take a sample of to test for a chest infection?

Answer 8

sputum

Question 9

What specimen you you take a sample of to test for tonsilitis?

Answer 9

throat swab

Question 10

What specimen you you take a sample of to test for a wound/abcess?

Answer 10

swab or pus

Question 11

What specimen you you take a sample of to test for infectious diarrhoea?

Answer 11

faeces

Question 12

What specimen you you take a sample of to test for sepsis?

Answer 12

blood culture

Question 13

What specimen you you take a sample of to test for menigitis?

Answer 13

cerebrospinal fluid (CSF)

Question 14

What specimen you you take a sample of to test for oral infections?

Answer 14

oral rinse, aspirate of pus.

Question 15

What are the steps which the lab use to test a bacterial infection?

Answer 15

microscopy (urgent/rapid)

culture

susceptibility testing

Question 16

Define commensal organism?

Answer 16

the typical or norm/ non-harmful

Question 17

How do you apply lab results clinically?

Answer 17

e.g. S. aureus can be commensal and a pathogen depending on context.

if skin is red and inflamed on an open wound then it is likely pathogenic

if the skin appears healthy with no open wound then it is likely commensal

Question 18

How does the lab test for a virus?

Answer 18

molecular methods - real time / multiple PCR e.g. throat/ nose swab.

antigen detection (Hepb)

serology to determine immunity e.g. blood sample

virtually obsolete methods e.g. electron microscopy, cell or tissue culture (inoculate cell line)

Question 19

What 3 areas are parasites divided into?

Answer 19

protozoa (malaria)
helminths (worms)
arthropods (lice/ticks)

important in developing countries

Question 20

Wha are the diagnostic principles in parasitology?

Answer 20

microscopy of different life cycles stages e.g. parasites, cysts and ova faeces

blood films for malaria

culture rarely possible