Cv: Test 2: 3. Blue/jackson : Viral Myocarditis & Chagas Disease

Front 1

What is the largest cause of myocarditis in the world?

Back 1

Chagas' disease

Front 2

What is the largest cause of myocarditis in the USA? 2nd?

***** Test

Back 2

Coxsackie B virus (adenovirus, is a close second!)

Front 3

Coxsackieviruses are what type of virus?

Back 3

Enteroviruses (aka they can infect from being digested)

note that Enteroviruses are members of the Picornavirus family

Front 4

do coxsackieviruses cause effects in just one area or are they more widespread effects. What is the underlying concept to this answer?

Back 4

they have widespread effects

they use receptors common to a variety of cell types

Front 5

What receptor do coxsackieviruses hit on myocytes?

Back 5

CAR receptor

it is the single point of entry on the cell surface

Front 6

do coxsackieviruses require a co-receptor or do they need a single one? What about adenovirus

Back 6

coxsackieviruses: single CAR receptor

adenovirus: CAR + co-receptor

Front 7

when do you have the highest density of CAR receptors?

Back 7

at birth!

they decrease over time

Front 8

what types of coxsackieviruses account for 80% of myocarditis?

Back 8

coxsackievirus B type 3/4

Front 9

60-70% of cases of neonatal myocarditis are acquired from where?

Back 9

The mother! (the mother has a cold during birth)

30-40 from hospital staff (the hospital staff has a cold and transmits it)

Front 10

why are babies more likely to get myocarditis? 2

Back 10

heavy CAR receptor density (coxsackievirus/adenovirus receptor)

insufficient specific and non specific immune response

Front 11

what is the onset of myocarditis in babies?

Back 11

onset in 1st 7 days

Front 12

do most babies affected with myocarditis survive?

Back 12

NO sadly; 50-75% mortality rate

Front 13

Do babies that survive myocarditis generally have full recovery, or do they have other cardiac problems as a result?

Back 13

generally have full recovery

Front 14

how do you diagnose myocarditis?

Back 14

Symptoms (tachypnea, tachycardia, anorexia, diaphoresis), ECG.

Isolation of virus/PCR detection of N.A. from any site (blood, respiratory secretions, feces, urine).

Front 15

in adolescents what is the mechanism of damage to the myocardium?

Back 15

coxsackievirus B initiates an auto-immune response

(remember there are less CAR receptors as you get older, so this they aren't what cause it!!)

Front 16

What is the mechanism of myocarditis in the adult?

Back 16

low level of car receptor, but coxsackievirus B can still replicate and cause myocyte damage

this leads to release of myosin, which is seen as foreign, leading to an immune response

you get a cell mediated and antibody response which leads to myocarditis

Continuing damage seems primarily auto-immune, mediated by cytotoxic T- lymphocytes, antibodies and macrophages.

Front 17

Blue summary slide 1: cause of myocarditis


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Back 17

Myocarditis more frequently follows viral infection (in contrast to bacterial, fungal). Primarily Coxsackieviruses, Adenoviruses. Most often asymptomatic, or short-lived, benign.

Front 18

Blue summary slide 2: myocarditis, how it occurs in children


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Back 18

In newborns, following myocyte infection, there may be widespread destruction of myocytes, due to an abundance of myocyte CAR receptors. High mortality rate if acquired in 1st week. Passive immunity is protective.

Front 19

Blue summary slide 3: myocarditis in adolescents/adults


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Back 19

In adolescents/adults, viral infection leads to limited myocyte damage, due to a greatly reduced level of CAR receptors, but may induce an anti-myocyte auto-immune mechanism. Can lead to chronicity, DCM, CHF, transplantation.

Front 20

Where does Chagas disease come from (in the world)

Back 20

central and south america

this makes a big clue

Front 21

what type of disease is Chagas Disease

Back 21

parasitic infection caused by trypanosoma cruzi

Front 22

12-year old Hispanic female presents to your clinic with headache, fever, malaise, and reported weight loss. Her left eye was swollen shut (Romaňa’s sign) and showed conjunctivitis. She has recently emigrated to the United States from a rural area of South America.

What would a blood smear reveal?

Back 22

when a person is infected in the acute phase (aka first few weeks) you would see small flagalleted organisms near the RBCs

Front 23

Trypanosoma cruzi tend to infect what kind of cells

Back 23

muscle cells (cardiac especially)

Front 24

what is meant by amastagote cell phase?

Back 24

when Trypanosoma cruzi infects it starts to replicate in a cell...that is this phase....they then replicate to the point of causing the cell to lyse

Front 25

what is responsible for the spread of Trypanosoma cruzi? how does it do this?

Back 25

Triatomid insect = reduviid = “Kissing bug”

it bites your face, then shits in the bite...aka it dumps on your face and you get infected....

Front 26

if you are staying in a 5 star hotel in south america should you worry about a kissing bug dropping a turd on your face?

Back 26

not really, they are normally found in rural areas with mud, thatch, or adobe homes

Front 27

there are 2 phases of chagas disease... what does the following describe?

Usually mild; weeks to months
Fever, fatigue, rash
Swelling at infection site; Chagoma
Rarely, myocarditis

Back 27

Acute phase

Front 28

there are 2 phases of chagas disease... what does the following describe?

Palpitations, dyspnea, syncope due to enlarged heart, altered heart rate or rhythm (may be fatal)
Dysphagia or constipation → due to mega-esophagus, mega-colon

Back 28

Chronic Phase

Front 29

if you see a patient has a history that shows they went to central america what should you immediately be thinking

Back 29

CHAGAS disease

Front 30

will you find organisms in the blood associated with chagas in the acute or chronic phase?

Back 30

acute! them lil shitters will be swimmin all up in your blood


hahah lil shitters...get it? because they got pooped into your face.