Cardiovascular Infections

Infective endocarditis is diagnosed based on Modified Duke Criteria.

Empiric antibiotics should be given to all patients who are haemodynamically unstable or who have an acute presentation, after blood cultures are taken.

In patients who are haemodynamically stable, with a subacute, indolent presentation, delay antibiotics until culture results are available.

Antimicrobial

Comments and Duration of Therapy 

Vancomycin IV 25-30mg/kg loading dose, then dose according to Vancomycin dosing section

PLUS

Cloxacillin 2g (child 50mg/kg) IV Q4H

PLUS

Gentamicin 4-5mg/kg (child <10 years old: 7.5mg/kg) IV OD

If patient is in septic shock replace Gentamicin with:

Cloxacillin is used in addition to vancomycin as it is more effective than vancomycin for methicillin-sensitive Staphylococcus aureus.

Seek review by Cardiology and Infectious Diseases where available.

Benzylpenicillin 3 million IU (1.8g) (child 80 000 IU (50mg)/kg) Q4H

PLUS

If gentamicin dose monitoring is available and there no contraindications to use. Gentamicin 1mg/kg IV TID or 3mg/kg (child 5mg/kg) IV OD for 2 weeks then stop.

See Aminoglycoside dosing section.

Alternative:

If benzylpenicillin is not available replace with:

Ampicillin 2g (child 50mg/kg) IV Q4H

OR

Ceftriaxone 2g (child 50mg/kg) IV OD

For patients with severe allergy to penicillin use:

Vancomycin IV, dose according to Vancomycin dosing section

Patients treated with long term gentamicin should have renal function monitored every two days and should be asked regularly about symptoms of ototoxicity such as vertigo or hearing loss. If symptoms occur cease gentamicin.

Duration:

For uncomplicated native valve disease, with MIC of 0.125mg/L or lower, in which gentamicin is used for two weeks, treat for a total of 2 weeks.

For patients with complicated disease (large vegetation, slow response to treatment, extra-cardiac infection), MIC of >0.125mg/L, OR where 2 weeks of gentamicin cannot be used, treat for a total of 4 weeks.

For patients with prosthetic valves, treat for 6 weeks.

If vancomycin is used, treat for 6 weeks.

Cloxacillin is more effective than vancomycin for methicillin-sensitive Staphylococcus aureus.

Antimicrobial 

Comments and Duration of Therapy 

For methicillin-sensitive Staphylococci:

Cloxacillin 2g IV Q4H

Consider ADDING:

Gentamicin 1mg/kg IV TID, or 3mg/kg OD for 2 weeks, if organism is susceptible, there are no contraindications, and gentamicin dose monitoring is available. See Aminoglycoside dosing section.

Consider ADDING:

Rifampicin 300mg PO TID after 3-5 days of cloxacillin, for 6 weeks, if organism is susceptible, drug is tolerated, and active TB has been ruled out.

For MRSA:

Replace cloxacillin with:

Vancomycin 25-30mg/kg IV loading dose, then dose according to Vancomycin dosing section. Add gentamicin and rifampicin where appropriate as described above.

Patients treated with long term gentamicin should have renal function monitored every two days and should be asked regularly about symptoms of ototoxicity such as vertigo or hearing loss. If symptoms occur cease gentamicin.

Delayed commencement of rifampicin is important to reduce the development of rifampicin resistance when the bacterial burden is high early in infection.

Duration:

Treat for 6 weeks IV.

If rifampicin is used, continue this for 6 weeks.

If gentamicin is used, stop this after 2 weeks.

See Staphylococcus aureus bacteraemia in Sepsis and Directed Therapy for Blood Stream Infections.

For beta-lactam susceptible:

Ampicillin 2g (child 50mg/kg) IV Q4H

PLUS

Gentamicin 1mg/kg IV TID, or 3mg/kg IV OD for 2 weeks, if no contraindications, and gentamicin is monitoring available. See Aminoglycoside dosing section.

If high level resistance to gentamicin, or gentamicin cannot be used ADD:

Ceftriaxone 2g (child >1 month, 50mg/kg) IV BID to ampicillin.

For beta-lactam resistant:

Vancomycin IV, dose according to Vancomycin dosing section

PLUS

Gentamicin 1mg/kg IV TID, or 3mg/kg IV OD for 6 weeks, if no contraindications, and gentamicin monitoring available. See Aminoglycoside dosing section.

Duration:

Beta-lactam susceptible: Treat for 4 weeks if uncomplicated native valve disease, and rapid response to therapy. Otherwise treat for 6 weeks. Stop gentamicin after 2 weeks.
Beta-lactam resistant: Treat for 6 weeks with both ampicillin and gentamicin if no contraindications.

Patients treated with long term gentamicin should have renal function monitored every two days and should be asked regularly about symptoms of ototoxicity such as vertigo or hearing loss. If symptoms occur cease gentamicin

Haemophilus parainfluenzae, Aggregatibacter spp., Cardiobacterium spp., Eikenella corrodens, and Kingella spp.

Antimicrobial 

Comments and Duration of Therapy

Culture negative endocarditis is commonly due to prior antibiotic therapy, but can also be caused by unusual pathogens including Bartonella, Brucella, Coxiella burnetii, Legionella, Mycoplasma and Tropheryma whipplei, however these cannot currently be diagnosed in Timor-Leste.

Where possible seek review by Infectious Diseases.

Antimicrobial

Comments and Duration of Therapy 

Bacterial pericarditis may occur as a consequence of direct spread from an intrathoracic focus, haematogenous spread or extension from a subdiaphragmatic focus. Prior to widespread antibiotic use bacterial pericarditis was a frequent complication of pneumococcal pneumonia. Where antibiotic use is common, bacterial pericarditis is most often associated with nosocomial bacteraemia, thoracic surgery, or immunosuppression, and Staphylococcus aureus is the most common cause. Tuberculosis is the most common cause of subacute or chronic purulent pericarditis.

Antimicrobial 

Comments and Duration of Therapy