17- diagnosing infections

Question 1

what is an antibody

Answer 1

blood protein produced in response to foreign materials recognized by immune system (antigen)

Question 2

ways to identify and diagnose and infection

Answer 2

** use different techniques to narrow possibility of what organism
microscopy

• cell shape and size
• cell arrangement
• gram staining

cell culture
- grow in sufficer numbers
- colony characteristics
- selective and differntial media- narrow possibilities

biochemical tests
- enzymes
- isolate pathogen- test genes for necessary to conduct metabolic produces

Question 3

what is an antigen

Answer 3

forge in materials recognized by immune system

Question 4

aseptic technique

Answer 4

** careful of contamination while collection and transport

Question 5

what need to be considered during collection of a sample

Answer 5

• labeling specimen
• temperature
• accuracy and reliability
• aseptic technique

Question 6

presumptive test

Answer 6

determine if pathogen MIGHT be present

Question 7

confirmatory test

Answer 7

• more detailed
• more costly
• more accurate then presumptive test
• identify what pathogen specifically
  IS PRESENT?

Question 8

etiological diagnosis

Answer 8

needed with dangerous diseases, determine exact causes agent

Answer 9

• isolated and grown in pure cultures
• hard to test just one bacteria
• provide food for bacteria to grow in culture
• virus need host cell to grow

Question 10

tests to detect enzyme activity

Answer 10

• detect presence or absence of specific substrates
• end product present ?
• enzyme present?

Question 11

Bergen manual of determinative bacteriology

Answer 11

• can bacteria carry out certain chemical reactions
• tables of biochemical test results
  (classification based on)

Question 12

mass spectrometry

Answer 12

• used to detect microbial enzyme activity
• specifically identify molecules
• biomarkers indicate specific species

Question 13

PCR test

Answer 13

• allow identification of infectious agent (examine DNA or RNA )
• AMPLIFIES tiny amount of nucleic acids
• rapid results

**drawback– cannot distinguish living from dead organisms

**so dont know if its a replicating virus or non infectious leftover debrief

Question 14

antigen testing

Answer 14

• markers for infection– presence of viral proteins
  (etc, surface spikes)
• advantages no expensive equipment required, on the spot results
• less accurate than PCR testing

Question 15

ANTIGens vs antibodies how they work together

Answer 15

antigens - capable of triggering immune system to produce antibodies

antibodies-
proteins produced in response to antigens - infection

Question 16

immune testing- serological reactions

Answer 16

• detect antigens or antibodies in patient samples
  *antibody would bind to antigen

if have an absorbable level- that antibody was probably produced in response to an infectious agent

• see if previously infected with a pathogen

Question 17

neutralization binding antibodies to antigens

Answer 17

• antibodies bind to antigen
• inhibit ability of molecule

-no visible evdinece

• must be injected into a lab animal to determine positivity