Day 7.2 and 7.3 Micro- Virology Flashcards
Use for acyclovir, ganciclovir
Acyclovir = HSV, VZV, EBV
Ganciclovir = CMV
If these fail, can use foscarnet.
HBsAg
Surface Ag
Have disease right now
HBsAb
Surface Ab
Either recovered from dz
OR have been immunized
HBcAg
Core Ag
Indicates new dz, but this is not something that can be measured in the serum, so won’t get a measurement for it on the test.
HBcAb
Core Ab
Hx of active dz (only- will NOT be positive if you have just been immunized)
What are the core HBV Ab?
IgM for early, active dz
IgG later, for chronic dz
HBeAg
E Ag Indicates active infection and HIGH lvl of transmissibility High E = High Enfectivity eg Chronic contagious
HBeAb
E Ab
Indicates infection but chonic, LOW transmissibility
eg Chronic low-infective
What will the HBV serologic markers show in active dz?
HBsAg +
HBsAb -
HBeAg +
HBeAb -
HBcAb + (IgM)
What will the HBV serologic markers show in the window period (equivalence zone)?
HBsAg -
HBsAb -
HBeAg -
HBeAb -
HBcAb + (IgM)
There are Ab present, but they’re all bound to Ag, so nothing is detected in the assay. Confusing, but you know it bc of the IgM core Ab, which indicate a newer infection.
What will the HBV serologic markers show in a chronic, highly infective state?
HBsAg +
HBsAb -
HBeAg +
HBeAb -
HBcAb + (IgG)
Think: dz is winning!
This is the same as active dz except for the core Ab is now IgG since it’s chronic.
What will the HBV serologic markers show in a chronic, low-infective state?
HBsAg +
HBsAb -
HBeAg -
HBeAb +
HBcAb + (IgG)
Will still have +surface Ag and -surf Ab bc you still have dz.
But, since it’s low infective (and E is for Enfectivity, your E Ag will be neg (and E Ab pos)
What will the HBV serologic markers show in complete recovery?
HBsAg -
HBsAb +
HBeAg -
HBeAb +
HBcAb + (IgG)
Winning! All Ag’s neg, all Ab’s positive
What will the HBV serologic markers show in an immunized pt who has never had dz?
HBsAg -
HBsAb +
HBeAg -
HBeAb -
HBcAb - (this is the only time core will be negative, if you have Ab. other scenario is never had it and never vaccinated)
Which Hepatitis virus is a DNA virus?
HBV
Transmission of chicken pox vs shingles
Chicken pox = respiratory
Shingles = only by direct contact w active lesions. Cover them and they won’t be spread.
Where does HSV1 lie dormant?
Trigeminal ganglion
Where does HSV2 lie dormant?
S2 and S3 ganglia
Where does VZV (chicken pox and shingles) lie dormant?
Trigeminal ganglia and dorsal root ganglia
What does EBV cause?
Infectious mono Burkitt's lymphoma (endemic) Hodgkin's lymphoma nasopharyngeal carcinoma thymic carcinoma oral hairy leukoplakia
What can EBV look similar to? If pt is treated for wrong thing, what happens?
Looks like strep throat
If pt is given aminopenicillins (amoxicillin) for the strep, they will get a rash (and will think they are allergic to amox)
EBV + amox = rash
If the pt has mono but has a negative monospot, what is the cause?
Probably CMV
When CMV affects AIDS pts, what are they prone to?
Pneumonia from CMV
Esophagitis from CMV
What age does roseola usu infect?
7-13 months
Roseola = HHV-6
What cancer can be caused by HBV and HCV?
Tumor marker for it?
Hepatocellular carcinoma Alpha feroprotein (AFP)
Main txmsn of HBV
Sexual Also parenteral (eg injection) and maternal-fetal
Main txmsn of HCV
Parenteral (IV drug users)
Also post-transfusion if blood not screened.
Rx for HCV
Alpha-interferon (Interferon-alpha)
Ribavirin
What causes aplastic crisis in sickle cell pts?
Parvo B19
Which papilloma viruses cause warts? CIN?
Warts = 1, 2, 6, 11
Cervical interepithelia neoplasia = 16, 18
What is the polyoma virus? What does it cause?
JC virus, causes PML in HIV pts
PML - progressive multifocal leukoencephalopathy
What is molluscum contagiousum?
Flesh-colored dome lesions w a central dimple (on skin)
It’s a poxvirus
Only DNA virus that is not double stranded?
Parvo B19
Downey cells
EBV
Downey cells are the abn circulating Cytotoxic T cells (atypical lymphocytes). They have a foamy cytoplasm.
Main char- yellow fever
High Fever
Hemorrhagic Dz- Black vom!
Jaundice
Can cause liver, renal dz
Weird tongue: red on tip and sides but white in center
Child w major diarrhea in winter months
Rotavirus
ROTA = right out the ass
Influenza virus Ag
Hemagglutinin- promotes viral entry
Neuraminidase- promotes release of progeny viruses
Pts w influenza are at risk for bacterial superinfection from what?
S. pneumonia, H. influenza, etc
Anything that causes pneumonia
Can be fatal.
Shift vs drift
Shift = Reassortment. Worse. (Oh Shift!)
Drift = minor chg based on random mutation.
Things that cause aseptic (viral) meningitis
Cocksackie virus
Echovirus
(they are both enteroviruses)
What is another name for measles virus?
Rubeola
(RUBy has measles, and is ruby red from head to toe)
(RuBELLA is visiting from Germany for 3 days)
(ROSEola is HHV-6. I want 6 roses for my birthday.)
T/F immunodeficient pts who get measles won’t have a rash or Koplik spots.
True.
The rash and spots are immune rxns, so pts w/o good immune systems won’t get them.
The reactions take place in the endothelial cells of dermal capillaries.
In what direction on the body does the measles rash spread?
From head to toe (can of paint)
What congenital heart defects are caused by Rubella?
PDA and Pulmonary Artery Stenosis
ruBELLA is visiting from Germany for 3-days.
What RNA viruses cause aseptic meningitis and myocarditis?
Echovirus
Coxsackie virus
Which polio vaccine is live attenuated?
Sabin is live-attenuated and given orally.
SalK is Killed.
How does polio cause paralysis?
Affects the motor neurons of the anterior horn.
1 cause of fatal diarrhea in kids
Rotavirus
What RNA virus is causes meningitis in summer months?
Echovirus, bc it is transmitted in swimming pools
Tourniquet test is for which RNA virus?
Dengue fever
West Nile Virus: reservoir, vectors, hosts
Reservoir- birds
Vectors- mosquitos
Incidental hosts (only bc mosquitos bite them): humans, horses, dogs
West Nile virus sympt
Most people: flu-like
1/150 have severe case: meningitis (possibly w encephalitis) incl muscle weakness and flaccid paralysis bc of anterior horn involvement.
Avian influenza
H5N1
Bird to human only
URI, diarrhea, fever, pancytopenia, elevated liver enz
Rx: oseltamavir (tamiflu)
H1N1 influenza
Swine flu
Flu + GI sympt
Rx oseltamavir or zanamivir but only in high risk or severly ill pts bc of wide spread resistance and side effects
Asthma sympt in a preemie in winter
RSV (bronchiolitis)
Rx for preemies in winter months
Passive immunization w Palivizumab (monoclonal RSV Ig) monthly during winter to protect them from RSV
Also give it to infants w chronic lung dz.