Serology

Question 1

IgG

Answer 1

70-75% of immunoglobulins

• half-life 3-4 weeks
• crosses the placenta
• 2 heavy and two light chains

Question 2

IgM

Answer 2

10-15 percent

• half/life 5 days
• too large to cross the placenta
• heavy chain, light chain and J chains
• can hold up to 10 if small

Question 3

Response of IgM/IgG

Answer 3

Primary response
- IgM peaks at 1-2 weeks
- IgG increases after 1-2 weeks 
Secondary increase
- rapid increase in IgG
- small increase in IgM

Question 4

False negatives for IgG/IgM

Answer 4

limited response, delayed response, in an IgM assay -IgG repeats

Question 5

False positives for Igs

Answer 5

similar antigen

• reactivation
• rhemuatoid factor ( attacks Fc region of IgG molecule and gives false IgM)
• need to remove IgM

Question 6

Immune status testing

Answer 6

is for past infection or vaccination

• vericella, mumps, rubella
• single sample

Question 7

Congential

Answer 7

aquired in utero

• Toxoplasma gondii, rubella, CMV, herpes
• IgM testing on neonatal blood

Question 8

VDRL

Answer 8

microscopic flocculation

• cardiolipin-lecthin- cholesterol antigen-non specific
• can test CSF

Question 9

RPR

Answer 9

aggultination- Reagin

• carfiolipin-charcol Ag- nonspecific
• confirmatory test needed

Question 10

FTA-ABS

Answer 10

flourescent treponemal Ab absorption

Question 11

MGA-TP

Answer 11

microagglutination assay

Question 12

Hep A

Answer 12

single stranded RNA genome

• icosahedral with no envelope
• fecal oral transmission
• headache, fatigue, nausea, vomiting, abdom. pain, jaundice, dark urine, sore muscles
• usually 1 month incubation, quick onset
• symptoms usually last 2 months
• positive HAV IgM
• supportive therapy
• vaccine avaliable

Question 13

Hep B

Answer 13

partial double stranded DNA genome

• icosahedral capsid with envelope
• spread by direct contact of fluid
• semen,vaginal fluid, saliva
• 90 incubation period with same symptoms as Hep A
• symptoms last 6 weeks or up to 6 months
• testing done on cobas looking ore Hep B surgace ab/ag, hep b core antidody( total or IgM)
• drs will use serology and other tests to make diagnosis
• envelope antigen/body not tested for at ALI

Question 14

Hep C

Answer 14

single stranded RNA genome

• spherical and icosahedral capsid with envelope
• spread through direct contact
• most are asymptomatic but others have the same as !.
• 75-80% of acute causes will become chronic
• cure is possible, genotyping can tell what drug to use
• can use EIA to diagnose but needs confrimation VIA PCR

Question 15

Hep D

Answer 15

ssRNA

• defective delta agent, needs helper to replicate
• Hep B is helper
• increases serverity of HEP B

Question 16

Hep E

Answer 16

no FDA kits, CDC tests

• 6-9 months for results
• africa, asia, central america
• self limiting
• diagnose with travel history, ruling out A-D and clinical presentation