What's new in streptococcal pharyngitis

Abstract

Upper respiratory tract infections are most frequent reason for a visit to a paediatrician. In Italy more than 5 million visits are made by children annually for pharyngitis and in 86% of cases an antibiotic is prescribed. Data from in 17 European countries show the rate of antibiotic prescription at such visits can be as high as 90% [1]. Prevention of acute rheumatic fever (ARF) has been a consideration in deciding whether to treat acute pharyngitis. Because ARF is increasingly rare and the prevalence of group A beta haemolytic streptococci (GABHS) in acute sore throat is only 20–30%, more than 70 000 patient treatments would be required to prevent one case of ARF. The benefits of effective antibiotic treatment include: reduction of suppurative complications, earlier resolution of fever and symptoms and limitation of person to person transmission of the organism [2,3]. The resurgence of serious infections due to GABHS have promoted interest in alternative treatments to penicillin and especially in their ability to eradicate the pathogen by the end of treatment. Failure of a standard 10-day course with penicillin V may be due to penicillin tolerance or increased virulence of the GABHS strain, inactivation by beta lactamases liberated in the tonsillary area by indigenous flora, or to non-compliance with treatment [4,5]. Favourable compliance with oral therapy is aided by a short duration of treatment, once or twice daily dosing schedule, lack of gastrointestinal reactions and taste. Penicillin V, is administered three times daily for 10 days [6] to achieve its maximal antimicrobial effect. Some studies suggest that penicillin taken twice daily is an effective treatment for streptococcal pharyngitis [7]. This dosage schedule is not standard and should be used only in families with known high compliance with treatment [6]. Patient compliance with standard penicillin treatment can be as low as 19% [8] or as 33% of those enrolled in a controlled study against amoxycillin [9]. GABHS pharyngitis is a self-limiting disease in which signs and symptoms tend to disappear spontaneously. Nelson [10] showed that 24 h after the start of therapy, fever and other symptons were present in less than 10% of the treated patients and in less than 20% of those receiving placebo. With the improvement of symptoms, the carer is tempted to modify or stop treatment [11]. Compliance may be improved with oral cephalosporins or the simplificationof dose schedules, e.g. administration of amoxycillin once daily for 10 consecutive days [12,13] or for 6 days bd [9]. The clinical and bacteriological results are comparable to standard penicillin V treatment of tds for 10 days.