Endocarditis, Lyme disease, HIV/AIDs

Question 1

Endocarditis presentation

Answer 1

fever and murmer

Question 2

Endocarditis dx

Answer 2

vegetations seen on echo and positive blood cultures

Question 3

Endocarditis etiology

Answer 3

It is rare to develop on healthy valves except in drug use. Risk of endocarditis it directly proportional to degree of damage. Regurgitant and stenotic lesions confer increased risk. Prosthetic valves associated with highest risk. Dental procedures confer and increased but small risk. Endoscopy confer no increased risk.

Question 4

Complications of endocarditis

Answer 4

Splinter hemorrhages, Janeway lesions (flat and painless), Osler nodes (raised and painful), Roth spots in the eyes, Brain (mycotic aneurysm), Kidney (hematuria, glomerulonephritis), conjunctival petechiae, Splenomegaly, Septic emboli to the lungs

Question 5

Endocarditis best initial test

Answer 5

Blood culture (95-99% sensitive)
Transthoracic echo (60% sensitive, 95% specific)
Transesophageal echo (95% sensitive and specific)
EKG rarely shows AV block if there is dissection of the conduction system (<5-10% sensitive)

Question 6

A man comes into the ED with fever and a murmur. Blood cultures grow Streptococcus bovis. Transthoracic echo shows a vegetation. What is the most appropriate next step in the management of this patient?

a. Colonoscopy
b. Transesophageal echo
c. CT of the abd
d. repeat the blood cultures
e. Surgical valve replacement

Answer 6

A. Strep bovis is associated with colonic pathology ranging from diverticuli to polyps to colon cancer.

Question 7

Diagnosis of culture negative endocarditis is based on

Answer 7

Oscillating vegetation on echocardiography and three minor criteria (fever, risk such as injection drug use or prosthetic valve, signs of embolic phenomena)

Question 8

Best initial empiric therapy for endocarditis

Answer 8

Vancomycin and gentamicin

Question 9

Endocarditis tx- viridans streptococci

Answer 9

Ceftriazone for 4wks

Question 10

Endocarditis tx- Staphylococcus aureus (sensitive)

Answer 10

Oxacillin, nafcillin, or cefazolin

Question 11

Endocarditis tx- Fungal

Answer 11

Amphotericin and valve replacement

Question 12

Endocarditis tx- Staphylococcus epidermidis or resistant staphylococcus

Answer 12

Vancomycin and gentamicin

Question 13

Endocarditis tx- Enterococci

Answer 13

ampicillin and gentamicin

Question 14

Tx of resistant organisms in endocarditis

Answer 14

Add an aminoglycoside and extend the duration of tx. Add rifampin for prosthetic valve endocarditis with Staphylococcus.

Question 15

When is surgery the answer in endocarditis?

Answer 15

CHF or ruptured valve or chordae tendineae, prosthetic valves, fungal endocarditis, abscess, AV block, recurrent emboli while on antibiotics

Question 16

Organisms difficult to culture that cause endocarditis.

Answer 16

HACEK
Haemophilus aphrophilus
Haemophilus parainfluenza
Actinobacillus
Cardiobacterium
Eikenella
Kingella

Question 17

Tx of HACEK organisms in endocarditis

Answer 17

Ceftriazone

Question 18

2 features required to establish a need for endocarditis prophylaxis

Answer 18

1. Significant cardiac defect. Prosthetic valve, previous endocarditis, cardiac transplant recipient with valvulopathy, unrepaired cyanotic heart disease
2. Risk of bacteremia. Dental work with blood, respiratory tract surgery that produces bacteremia

Question 19

Drug choice for endocarditis prophylaxis

Answer 19

amoxicillin prior to procedure. If PCN allergic tx with clindamycin, azithromycin, or clarithromycin

Question 20

Procedures and defects that do not require endocarditis prophylaxis

Answer 20

Flexible endoscopies, even with biopsy
Obstetrical and gynecologic procedures
Urology procedures (including prostate biopsy)
GI procedures including ERCP
Valvular heart disease including mitral valve prolapse, even with a murmur
Mitral regurgitation, mitral stenosis, aortic regurgitation, aortic stenosis, HOCM, ASD

Question 21

Lyme disease bug

Answer 21

Spirochete Borrelia burgdorferi

Question 22

Lyme disease transmitted by

Answer 22

deer tick, only 20% of patients recall the bite of the tick. Patients recently hiking or camping. Ixodes tick only present in northeast states (Connecticut, Massachuetts, New York, and New Jersey). Tick must be on the body 24hrs.

Question 23

Lyme disease presentation

Answer 23

Rash (Erythema migrans)- 5-14 days post exposure. Bull’s eye lesion
Joint pain- most common long term manifestation. Manifests in 60% of patients without tx. Oligoarthritis. Joint fluid with 25,000 WBCsul. Knee is most common.
Neurological manifestation- 10-15% of patients. CNS or PNS such as meningitis, encephalitis, or cranial nerve palsy. 7th CN most common (bells palsy)
Cardiac- 4-10% of patients. Damage to any part of the mycocardium or pericardium such as myocarditis or ventricular arrhythmia. Transient AV block most common cardiac manifestation

Question 24

Lyme disease diagnostic test

Answer 24

Not necessary if rash typical for Lyme disease. Serology testing for all other presentations. Testing with IgM, IgG, ELISA, Western blot, and PCR testing

Question 25

Asymptomatic tick bite tx

Answer 25

No routine tx

Question 26

Lyme disease presenting only with rash tx

Answer 26

Doxycycline or amoxicillin

Question 27

Lyme disease presenting with joint pain, 7th CN palsy

Answer 27

Doxycycline or amoxicillin

Question 28

Lyme disease presenting with cardiac and neurologic manifestations other than 7th CN tx

Answer 28

IV ceftriaxone

Question 29

Indication for a single dose of Doxy within 72hrs of tick bite

Answer 29

Ixodes scapularis clearly identified as the tick causing the bite
Tick attached for longer than 24-48hrs
Engorged nymph-stage tick
Endemic area