Serious Infections

Question 1

What is the most common cause of bacterial endocarditis?

Answer 1

Staph aureus

Question 2

Which patients should get a TOE to investigate endocarditis?

Answer 2

All patients except those with a negative TTE and a low clinical suspicion of endocarditis

Question 3

What percentage of patients with a bacterial endocarditis will have a negative echocardiogram?

Answer 3

15% - so if negative repeat in 7-10 days

Question 4

What is the mechanism of action of beta lactams?

Answer 4

Binds to the penicillin binding protein which prevents transpeptidation for bacterial cell wall synthesis

Question 5

What is the treatment for enterococcus faecalis endocarditis?

Answer 5

Amoxicillin and ceftriaxone for 6 weeks

Question 6

Should all patients with staph aureus bacteraemia have an echocardiogram?

Answer 6

Yes

Question 7

What is the recommended duration of treatment for staph aureus bacteraemia?

Answer 7

2 weeks if uncomplicated (no endocarditis, no prosthesis, negative cultures after 2-4 days)
4-6 weeks if complicated

Question 8

What are the most common pathogens in meningitis?

Answer 8

Streptococcus pneumonia (most common)
Neisseria meningitides (more common under 60)
Listeria monocytogenes (more common over 60)
Haemophilis influenza
Strep agalactiae

Question 9

What are risk factors for pneumococcal meningitis?

Answer 9

Otitis media, sinusitis, mastoiditis, CSF leak, cochlear implants, asplenia, HIV/AIDS, immunosuppression

Question 10

Which patients should you consider listeria meningitis in?

Answer 10

Age > 50, long term glucocorticoids/immunosuppression, diabtes, alcoholism, cirrhosis, ESRF, malignancy, HIV/AIDS, organ transplantation

Question 11

Which patients should you suspect meningococcal meningitis in?

Answer 11

Young adults without comorbidities

Question 12

Which patients should have a CT prior to LP in suspected meningitis?

Answer 12

Decreased consciousness, focal neurological deficit, papilloedema, new onset seizures, immunocompromised, known phx of mass lesion/stroke
(however these indications are controversial)

Question 13

What are the CSF findings for bacterial meningitis?

Answer 13

Opening pressure >20, positive gram stain, protein > 1g/L, low glucose, white cell count >1000 with >50% PMNs

Question 14

What is the benefit of a PCR panel on CSF sample?

Answer 14

Has good sensitivity even when sample taken post antibiotic treatment

Question 15

What are the clinical benefits of dexamethasone in pneumococcal meningitis?

Answer 15

Reduced mortality, reduced hearing loss/other neurologic sequelae

Question 16

When and how should dexamethasone be given for pneumococcal meninigits?

Answer 16

Start with or before first dose antibiotics, given 10mg IV Q6H for 4/7

Question 17

Is there a role for dexamethasone in meningococcal meningitis?

Answer 17

No – can be stopped once diagnosed

Question 18

What is the empiric therapy for meningitis?

Answer 18

Dexamethasone
Ceftriaxone 2g IV Q12H
+/- vancomycin
+/- benzylpenicillin

Question 19

What is the alternative to ceftriaxone if there is severe allergy?

Answer 19

Moxifloxacin

Question 20

Which patients should receive vancomycin?

Answer 20

If gram positive diplococci on gram stain, pneumococcal antigen assay positive or known/suspected otitis media/sinusitis (e.g. if suspected ceftriaxone resistant strep pneumoniae)

Question 21

Which patients should receive benzylpenicillin?

Answer 21

Age > 50, immunocompromised, pregnant, alcohol abuse (e.g. suspected listeria monocytogenes)

Question 22

Who should get post exposure prophylaxis for meningococcal meningitis?

Answer 22

Household contacts or health care workers who have performed airway management without a mask

Question 23

Which patients should get vaccinated for meningitis in adulthood?

Answer 23

Asplenia, CSF leak, cochlear implants, complement deficiency, HIV/AIDS, transplant recipients

Question 24

What is seen on peripheral blood film for patients post splenectomy?

Answer 24

Howell-Joly bodies

Question 25

What are the common pathogens for post splenectomy infections?

Answer 25

Streptococcus pneumoniae, heamophilis influenze type b, Neisseria meningitides

Question 26

What vaccines should be given in asplenia?

Answer 26

PCV13 then PPV23 5 yearly
4vMenCV (2 doses then 5 yearly)
MenBV (2 doses)
Hib (if hadn’t had in childhood)
Annual influenza vaccine