Infections of Cardiology (Exam 4) Flashcards
What is myocarditis?
Focal or diffuse inflammation of the myocardium. Most cases are infectious and often follow a URI.
What is the most common cause of myocarditis in the US?
Viral (adenovirus, coxsackie virus, parvovirus B19, HIV, CMV)
What are some other causes of myocarditis?
Bacteria (Brucellosis, strep pneumo, Legionella, Staph, Strep, Mycoplasma)
OR
Fungus (Candida, Aspergillus)
Symptoms of myocarditis.
Acute heart failure without previous symptoms.
Pleural/pericardial pain
Tachycardia
Diagnostic studies of myocarditis.
EKG: Nonspecific ST changes, ventricular ectopy
Chest XR: often shows cardiomegally
Treatment of myocarditis
If bacterial or fungal, treat with antimicrobial.
Treat symptoms of HF
Transplant
What is pericarditis?
Infection/inflammation of the pericardium. Often occurs in conjunction with myocarditis.
Causes of pericarditis?
Same as myocarditis.
Viral (adenovirus, coxsackie virus, parvovirus B19, HIV, CMV)
Bacteria (Brucellosis, strep pneumo, Legionella, Staph, Strep, Mycoplasma)
Fungus (Candida, Aspergillus)
Symptoms of pericarditis?
Chest pain, symptoms of myocarditis (Heart failure, tachycardia)
Physical exam finding consistent with pericarditis?
Will be able to auscultate a rub.
What is endocarditis?
Infection of the endocardial surfaces of the heart valves.
What patient populations are at higher risk for endocarditis?
IV drug users
Pt’s after prosthetic valve replacement
History of rheumatic fever
Male: female ratio 2: 1
Most common bacteria involved with endocarditis?
Strep Viridans, Staph, Gram negative rods, Enterococci
Most common causes of native valve endocarditis?
Acute usually do to Staph or Group B Strep
Subacute usually alpha hemolytic strep (strep Viridans)
Most common cause of prosthetic valve endocarditis?
Occurs within 60 days of replacement: Staph and Candida
Occurs later than 60 days after replacement: staph and alpha hemolytic strep
What valve is most often infected in IV drug users?
What bacteria is most commonly responsible?
Tricuspid valve.
Most commonly Staph Aureus (60%)
Physical exam findings consistent with endocarditis?
New heart murmur or worsening of an old murmur. Peripheral stigmata (splinter hemorrhages, Osler nodes, Janeway lesions, Roth spots), embolic findings
Symptoms of endocarditis
Fever and chills most common
Others include anorexia, weight loss, night sweats, headache, myalgias, SOB
What are Osler nodes?
Painful raised lesions on hands and feet
What are Janeway lesions?
Flat, painless, purple lesion on hands or feet
What are Roth spots?
Retinal hemorrhages with white or pale centers
What diagnostics might you order if you suspect endocarditis?
Echocardiogram -60% sensitive
Transesophageal echocardiogram- 90% sensitive
Blood cultures, CBC, ESR(elevated in 90% of cases)
If you highly suspect endocarditis, yet blood cultures are negative, what might you order?
Serologies for chlamydia, q fever, bartonella, fungal culture, and HACEK culture.
What are HACEK organisms?
HACEK stands for the bacteria that are slow growing.
Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella
How do you use the Duke Criteria?
Use the Duke Criteria to diagnose endocarditis. A patient must meet either 2 major criteria, 1 major and 3 minor criteria, or 5 minor criteria.
What are the major Duke Criteria?
Blood culture positive from 2 separate cultures consistent with organisms that cause IE.
Positive echocardiogram.
What are the minor Duke Criteria
Predisposition for IE Fever Vascular phenomena (peripheral stigmata) Immunologic phenomena Microbiologic evidence Echo results showing valve thickening without vegetation
Does this patient meet Duke Criteria?
One positive blood culture growing Eikenella and a positive echocardiogram?
No! Patient must have 2 separate cultures in order to meet the major criteria.
Does this patient meet Duke Criteria?
Blood cultures pending. Positive echocardiogram. Fever, Osler nodes, and the patient has hx of rheumatic fever.
Yes, this patient has 1 major and 3 minor criteria(Fever, vascular phenomena, and predisposition for IE).
What antibiotics would you use to treat a patient with IE before you have culture results?
Vancomycin and Cephtriaxone are used for empiric treatment
What might you use for IE caused by strep and why?
Penicillin and gentamycin, because they work synergistically
What antibiotic would you use for IE caused by MSSA?
Nafcillin
What antibiotic would you use for an infection of a prosthetic valve and why?
Daptomycin 6mg/kg. It is effective against biofilms.
How long do you treat for IE?
At least 2 weeks, 6 weeks if blood cultures are negative.
Last resort treatment?
Surgery
What valve(s) is most likely to be infected in a patient with peripheral stigmata?
Left sided valves: Aortic or mitral. Emboli get stuck in capillaries of hands and feet causing splinter hemorrhages, Janeway lesions, Osler nodes
What valve(s) is most likely to be infected in a person with PE’s.
Right sided valves: tricuspid or pulmonic
Emboli break off and get stuck in capillaries of lungs causing PE’s.
What might you consider if a pt has IE due to enterococci?
Consider GI tract as source, rule out colon cancer.
What is the most commonly infected valve?
What is the least common?
Most common: Mitral
Least common: Pulmonic
