IDMM investigations (3)

Question 1

what categories of inquiry make up a thorough physical exam?

Answer 1

1. presenting complaint/HPI
2. past medical Hx
3. vaccinations
4. travel/immigration
5. assessment of risk behaviors
6. animal/pet/occupation/environmental exposures
7. meds (current and past) *antibiotic exposure in the last 6 months

Question 2

what elements/systems must be examined on a thorough physical exam?

Answer 2

1. general appearance
2. CV/hemodynamic status
3. skin
4. lymph nodes
5. eyes
6. respiratory
7. abdomen
8. genital exam
9. MSK

Question 3

what is noted within HPI

Answer 3

duration

constitutional symptoms (associated)

fever/chills/rigors/night sweats etc…

weight loss

provocation/palliation

Question 4

physical exam: general appearance

Answer 4

body habitus

urgency

distress

LOC

Question 5

physical exam: CV/hemodynamic status

Answer 5

BP

perfusion

murmurs

Question 6

physical exam: skin

Answer 6

color
cyanosis
rash
scars
wounds
peripheral stigmata for deeper infections

Question 7

physical exam: lymph nodes

Answer 7

lymphadenopathy

cervical, inguinal, axillary, extremity

Question 8

physical exam: eyes

Answer 8

conjunctivitis
drainage
cellulitis (orbital, preorbital)
fundoscopic examinations

Question 9

physical exam: respiratory

Answer 9

respiratory rate
auscultation (wheezes, crackles)
percussion resonance

Question 10

physical exam: abdomen

Answer 10

tenderness

hepatosplenomegaly

Question 11

physical exam: genital exam

Answer 11

genital/anal lesions
abnormal discharge
inguinal adenopathy

Question 12

physical exam: MSK

Answer 12

joints
spine (movement, tenderness, swelling)

Question 13

list the 5 sites of infection

Answer 13

1. SST
2. respiratory
3. GI tract (most in lower but some in upper)
4. genitourinary tract
5. sterile site

Question 14

what can be tested for on a blood test?

Answer 14

WBC
hemoglobin
platelets
liver function tests

Question 15

what does elevated WBC in a blood test indicate?

Answer 15

broad stimulation of immune response

Question 16

what two factors on blood tests may be elevated in inflammation?

Answer 16

C reactive protein

erythrocyte sedimentation rate (ESR)

Question 17

why do we we blood tests for procalcitonin?

Answer 17

it is released in response to bacterial toxins but downregulated in viral infections

helps differentiate cause of infection

Question 18

what are the “acute phase reactants?”

what are they used for?

Answer 18

(on blood tests)

acute phase reactants = CRP and ESR

used for diagnosis of rheumatological conditions or for monitoring inflammation

Question 19

what factors are assessed in urinalysis

Answer 19

1. inflammation: WBCs, RBCs, leukocyte esterase

2. presence of bacteria: microscopy, nitrite

Question 20

list indications for urinalysis

Answer 20

1. complicated infection
2. atypical symptoms
3. failure to respond to therapy
4. recurrent symptoms less than one month after previous

Question 21

how are urine cultures quantified?

Answer 21

by CFU (colony forming units)

this is unlike other cultures

the test is significant if >100 000 CFU/mL (+symptomatic +pyuria)

mixed infections are rare

Question 22

list the specimen types used in microbiologic analysis

Answer 22

virus
typical bacteria
atypical bacteria
fungi
parasite

Question 23

what are the two diagnostic methods for microbiological analysis

Answer 23

1. microscopy

2. gram stain

Question 24

are gram stains done on urine or stool

Answer 24

no

Question 25

what is the purpose of microscopy

Answer 25

can ID all groups of pathogens, based on stains, size, shapes

Question 26

what is the purpose of gram stain

Answer 26

MOST IMPORTANT

automatically performed on respiratory and wound tissue/fluid samples and blood samples

can indicate presence of inflammation, amount of organisms and presumptive ID

Question 27

what are some limitations of susceptibility testing

Answer 27

1. breakpoints can be unclear
2. in vitro may not predict final outcome in vivo (due to pharmacodynamic and pharmacokinetics)
3. MIC measurements are not always reliable
4. other host factors (i.e immune system)

Question 28

on which tissues is gram staining used?

Answer 28

NOT on stool
NOT on urine

yes on respiratory (though often contaminated with oral flora), SST, genital and sterile site samples

Question 29

on which tissues is culture and sensitivity used?

Answer 29

on all tissues, though less on genital

Question 30

on what suspected pathogen samples is microscopy used?

Answer 30

NOT on viruses

yes to bacteria, atypical bacteria, fungi and parasites

Question 31

on what suspected pathogen samples is culture used?

Answer 31

sometimes on viruses
yes on bacteria, atypical bacteria and fungi
NOT on parasites

Question 32

on what suspected pathogen samples if nucleic acid testing used?

Answer 32

YES on viruses
sometimes on bacteria/atypical bacteria
NOT on fungi or parasites

Question 33

on what suspected pathogen samples if antigen testing used

Answer 33

sometimes on viruses, atypical bacteria, fungi and parasites

NOT on typical bacteria

Question 34

on what suspected pathogen samples is serology testing used?

Answer 34

YES on viruses
NOT on bacteria
sometimes on atypical bacteria, fungi, parasites

Question 35

what is the nucleic acid amplification test

Answer 35

it is a molecular identification method
PCR = one quick method to test for nucleic acids

advantages = sensitive, specific, quick

disadvantages = limited to specific target, may not detect viable organisms and expensive

Question 36

list some antigen detection methods

Answer 36

ELISA
EIA
western blot
cytotoxin assays

advantages = quick, specific

disadvantages = poor sensitivity, limited to specific target, may not detect viable organism

Question 37

list some antibody detection methods

Answer 37

serology
IGRA
TB skin test