Secondary prophylaxis

Secondary prophylaxis with benzathine penicillin G (BPG) is recommended for all people with a history of ARF or RHD. Four-weekly BPG is currently the treatment of choice, except in patients considered to be at high-risk, for whom 3-weekly administration is recommended. The benefits of 3-weekly BPG injections are offset by the difficulties of achieving good adherence, even to the standard 4-weekly regimen. Data from the Northern Territory show that few, if any, recurrences occurred among people who fully adhered to a 4-weekly benzathine penicillin G regimen.

Alternatives to benzathine penicillin G are available, although they are less effective and require careful monitoring.

• In patients who refuse intramuscular benzathine penicillin G, oral penicillin can be offered, although it is less effective than benzathine penicillin G in preventing group A streptococcal (GAS) infections and subsequent recurrences of acute rheumatic fever. The consequences of missed oral doses must be emphasised, and adherence monitored.
• In patients who may be allergic to penicillin, an allergist should be consulted. The rates of allergic and anaphylactic reactions to monthly benzathine penicillin G are low, and fatal reactions are exceptionally rare. There is no increased risk with prolonged benzathine penicillin G use.
• In patients with a confirmed, immediate and severe allergic reaction to penicillin, a non-beta- lactam antimicrobial (e.g. erythromycin) should be used instead of benzathine penicillin G.
• In pregnant patients, penicillin prophylaxis should continue for the duration of pregnancy to prevent recurrent acute rheumatic fever There is no evidence of teratogenicity. Erythromycin is also considered safe in pregnancy, although controlled trials have not been conducted.
• In anticoagulated patients, benzathine penicillin G injections should be continued unless there is evidence of uncontrolled bleeding, or the international normalised ratio is outside the defined therapeutic window.

The appropriate duration of secondary prophylaxis is determined by a number of factors including age, time since the last episode of ARF, ongoing risk of streptococcal infections and potential harm from recurrent acute rheumatic fever.

Infective endocarditis is a dangerous complication of rheumatic heart disease and a common adverse event following prosthetic valve replacement in Aboriginal and Torres Strait Islander Australians. People with established rheumatic heart disease or prosthetic valves should receive antibiotic prophylaxis prior to procedures expected to produce bacteraemia (e.g. dental procedures, surgical procedures where infection is present).