Endocarditis and other infections

Question 1

What is the likely focus of infection for Streptococcus pneumoniae?

Answer 1

Pneumonia or meningitis

Question 2

What is the likely focus of infection for E. Coli/Klebsiella/other coliforms?

Answer 2

Urinary tract or gut

Question 3

What is the likely focus of infection for staphylococcus aureus?

Answer 3

Skin or wound infection
Bone/joint infection
Endocarditis

Question 4

Describe the characteristics of the staphylococcus genus

Answer 4

Gram-positive
Round (coccus)
Found in cells, pairs or most commonly in clusters (name derived from Greek for ‘a bunch of grapes’

Question 5

How is the staphylococcus genus divided?

Answer 5

There ability to produce the blood clotting enzyme, coagulase
Coagulase positive and negative

Question 6

Is staphylococcus aureus coagulase positive or negative?

Answer 6

Coagulase positive

Question 7

Is staphylococcus epidermis coagulase positive or negative?

Answer 7

Coagulase negative

Question 8

What bacteria is associated with prosthetic material?

Answer 8

Staphylococcus epidermis

Question 9

What is infective endocarditis?

Answer 9

It is an infection of the endothelium of the heart valves

Question 10

Give predisposing factors for infective endocarditis

Answer 10

Heart valve abnormality (calcification/stenosis, congenital heart disease or post rheumatic fever), prosthetic heart valve, intravenous drug user or intravenous lines

Question 11

What is the pathogenesis of endocarditis?

Answer 11

Damaged heart valve
Turbulent blood flow over rough endothelium
Platelet/fibrin attachment
Bacteraemia (may be very transient)
Organisms settle in platelet/fibrin thrombi, forming a microbial vegetation
This affects the function of the heart valves and bits can break off and travel in circulation, lodging in capillary beds

Question 12

What side of the heart is usually affected by endocarditis?

Answer 12

The left side - aortic and mitral valves

Question 13

What valve tends to be affected in intravenous drug users?

Answer 13

Tricuspid

Question 14

What organisms cause endocarditis?

Answer 14

Staphylococcus aureus (38%)
Viridians streptococci (31%)
Enterococcus sp. (8%)
Staphlycoccus epidermidis (6%)

Question 15

What are the atypical bacteria that can cause endocarditis?

Answer 15

Bartonella, coxiella burnetii, chlamydia, legionella, mycoplasma and brucella

Question 16

What are the presenting symptoms of acute endocarditis?

Answer 16

Overwhelming sepsis and cardiac failure

Question 17

What are the symptoms for subacute endocarditis?

Answer 17

Fever, malaise, weight loss, tiredness and breathlessness

Question 18

What are the signs of subacute endocarditis?

Answer 18

Fever, new or changing heart murmurs, finger clubbing, splinter haemorrahages, Osler nodes, Janeway lesion, Roth spot, splenomegaly and microscopic haematuria.

Question 19

How many blood cultures do you do for a diagnosis of endocarditis?

Answer 19

3

Question 20

What is the second method of diagnosis?

Answer 20

Echocardiogram

Question 21

What bacteria tend to cause early presentations of prosthetic valve endocarditis?

Answer 21

Staphylococcus aureus and staphylococcus epidermis

Question 22

What bacteria tends to cause endocarditis in intravenous drug users?

Answer 22

Staphylococcus aureus

Question 23

How does endocarditis often present in intravenous drug users?

Answer 23

Staphylococcus aureus pneumonia

Question 24

Describe the general treatment for all types of endocarditis

Answer 24

IV antibiotics at a high dose and high frequency

Question 25

What drugs would be given for native endocarditis?

Answer 25

Amoxicillin and gentamicin IV

Question 26

What drugs would be given for prosthetic valve endocarditis?

Answer 26

Vancomycin and gentamicin IV and rifampicin PO | usually need valve replacement

Question 27

What drugs would be given for drug user endocarditis?

Answer 27

Flucloxacillin IV

Question 28

What drug is given for o Staphylococcus aureus (not MRSA)?

Answer 28

Flucloxacillin IV

Question 29

What drugs are given for MRSA?

Answer 29

Vanconycin IV and rifampicin PO

Question 30

What drugs are given for o Viridians streptococci?

Answer 30

Benzylpenicillin and gentamicin IV

Question 31

What drugs are given for o Enterocossus sp.?

Answer 31

Amoxicillin/Vancomycin & gentamicin IV

Question 32

What drugs are given for o Staphylococcus epidermidis?

Answer 32

Vancomycin and gentamicin IV and rifampicin PO

Question 33

What is monitored during therapy?

Answer 33

Cardiac function, temperature and serum C-reactive protein

Question 34

How is endocardisi prevented?

Answer 34

Prophylaxis use of antibiotics in high risk patients during gastrointestinal or genitourinary tract procedures if infection in this area is suspected

Question 35

What is myocarditis?

Answer 35

Inflammation of the cardiac muscle

Question 36

What are the symptoms of myocarditis?

Answer 36

Fever, chest pain, shortness of breath and palpitations

Question 37

What are the signs of myocarditis?

Answer 37

Arrythmia and cardiac failure

Question 38

What is the main cause of myocarditis?

Answer 38

Enteroviruses

Question 39

What is pericarditis?

Answer 39

Inflammation of the pericardium