Short-course antibiotic treatment of 4782 culture-proven cases of group A streptococcal tonsillopharyngitis and incidence of poststreptococcal sequelae

Different antibiotic treatments for group A streptococcal pharyngitis

BACKGROUND

Antibiotics provide only modest benefit in treating sore throat, although their effectiveness increases in people with positive throat swabs for group A beta-haemolytic streptococci (GABHS). It is unclear which antibiotic is the best choice if antibiotics are indicated. This is an update of a review first published in 2010, and updated in 2013, 2016, and 2021.

OBJECTIVES

To assess the comparative efficacy of different antibiotics in: (a) alleviating symptoms (pain, fever); (b) shortening the duration of the illness; (c) preventing clinical relapse (i.e. recurrence of symptoms after initial resolution); and (d) preventing complications (suppurative complications, acute rheumatic fever, post-streptococcal glomerulonephritis). To assess the evidence on the comparative incidence of adverse effects and the risk-benefit of antibiotic treatment for streptococcal pharyngitis.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2023, Issue 2), MEDLINE Ovid, Embase Elsevier, and Web of Science (Clarivate) up to 19 March 2023.

SELECTION CRITERIA

Randomised, double-blind trials comparing different antibiotics, and reporting at least one of the following: clinical cure, clinical relapse, or complications and/or adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened trials for inclusion and extracted data using standard methodological procedures recommended by Cochrane. We assessed the risk of bias in the included studies according to the methods outlined in the Cochrane Handbook for Systematic Reviews of Interventions, and used the GRADE approach to assess the overall certainty of the evidence for the outcomes. We reported the intention-to-treat analysis, and also performed an analysis of evaluable participants to explore the robustness of the intention-to-treat results.

MAIN RESULTS

We included 19 trials reported in 18 publications (5839 randomised participants): six trials compared penicillin with cephalosporins; six compared penicillin with macrolides; three compared penicillin with carbacephem; one compared penicillin with sulphonamides; one compared clindamycin with ampicillin; and one compared azithromycin with amoxicillin in children. All participants had confirmed acute GABHS tonsillopharyngitis, and ages ranged from one month to 80 years. Nine trials included only, or predominantly, children. Most trials were conducted in an outpatient setting. Reporting of randomisation, allocation concealment, and blinding was poor in all trials. We downgraded the certainty of the evidence mainly due to lack of (or poor reporting of) randomisation or blinding, or both, heterogeneity, and wide confidence intervals. Cephalosporins versus penicillin We are uncertain if there is a difference in symptom resolution (at 2 to 15 days) for cephalosporins versus penicillin (odds ratio (OR) for absence of symptom resolution 0.79, 95% confidence interval (CI) 0.55 to 1.12; 5 trials, 2018 participants; low-certainty evidence). Results of the sensitivity analysis of evaluable participants differed (OR 0.51, 95% CI 0.27 to 0.97; 5 trials, 1660 participants; very low-certainty evidence). Based on an analysis of evaluable participants, we are uncertain if clinical relapse may be lower for cephalosporins compared with penicillin (OR 0.55, 95% CI 0.30 to 0.99; number needed to treat for an additional beneficial outcome (NNTB) 50; 4 trials, 1386 participants; low-certainty evidence). Very low-certainty evidence showed no difference in reported adverse events. Macrolides versus penicillin We are uncertain if there is a difference between macrolides and penicillin for resolution of symptoms (OR 1.11, 95% CI 0.92 to 1.35; 6 trials, 1728 participants; low-certainty evidence). Sensitivity analysis of evaluable participants resulted in an OR of 0.79 (95% CI 0.57 to 1.09; 6 trials, 1159 participants). We are uncertain if clinical relapse may be different (OR 1.21, 95% CI 0.48 to 3.03; 6 trials, 802 participants; low-certainty evidence). Children treated with macrolides seemed to experience more adverse events than those treated with penicillin (OR 2.33, 95% CI 1.06 to 5.15; 1 trial, 489 participants; low-certainty evidence). However, the test for subgroup differences between children and adults was not significant. Azithromycin versus amoxicillin Based on one unpublished trial in children, we are uncertain if resolution of symptoms is better with azithromycin in a single dose versus amoxicillin for 10 days (OR 0.76, 95% CI 0.55 to 1.05; 1 trial, 673 participants; very low-certainty evidence). Sensitivity analysis for per-protocol analysis resulted in an OR of 0.29 (95% CI 0.11 to 0.73; 1 trial, 482 participants; very low-certainty evidence). We are also uncertain if there was a difference in relapse between groups (OR 0.88, 95% CI 0.43 to 1.82; 1 trial, 422 participants; very low-certainty evidence). Adverse events were more common with azithromycin compared to amoxicillin (OR 2.67, 95% CI 1.78 to 3.99; 1 trial, 673 participants; very low-certainty evidence). Carbacephem versus penicillin There is low-certainty evidence that compared with penicillin, carbacephem may provide better symptom resolution post-treatment in adults and children (OR 0.70, 95% CI 0.49 to 0.99; NNTB 14.3; 3 trials, 795 participants). Studies did not report on long-term complications, so it was unclear if any class of antibiotics was better at preventing serious but rare complications.

AUTHORS' CONCLUSIONS

We are uncertain if there are clinically relevant differences in symptom resolution when comparing cephalosporins and macrolides with penicillin in the treatment of GABHS tonsillopharyngitis. Low-certainty evidence in children suggests that carbacephem may be more effective than penicillin for symptom resolution. There is insufficient evidence to draw conclusions regarding the other comparisons in this review. Data on complications were too scarce to draw conclusions. Antibiotics have a limited effect in the treatment of GABHS pharyngitis and the results do not demonstrate that other antibiotics are more effective than penicillin. In the context of antimicrobial stewardship, penicillin can be used if treatment with an antibiotic is indicated. All studies were conducted in high-income countries with a low risk of streptococcal complications, so there is a need for trials in low-income countries and disadvantaged populations, where the risk of complications remains high.

Examining the Efficacy of Antimicrobial Therapy in Preventing the Development of Postinfectious Glomerulonephritis: A Systematic Review and Meta-Analysis

Postinfectious glomerulonephritis (PIGN) is an immune-mediated acute glomerulonephritis classically seen weeks after infection with Streptococcus pyogenes, although other infectious etiologies have emerged. While it has become increasingly rare in industrialized regions, it continues to affect children in developing countries. There has been debate as to why incidence rates are declining, including the possibility of improved initial treatment of bacterial infections. The ability of antimicrobial therapy in preventing PIGN as infectious sequelae, however, has not been comprehensively assessed. As varying evidence from published studies exists, the objective of this meta-analysis is to determine if antimicrobial therapy utilized to treat an initial infection has an effect in reducing the development of PIGN in humans. EMBASE, MEDLINE, and CENTRAL were searched using a comprehensive terminology strategy. From an initial search that returned 337 publications, 9 articles were included for analysis. Eight studies showed an incidence of PIGN after antimicrobial use ranging from 0.05% to 10% with a mean standardized difference (MSD) of 0.03 (0.01–0.06). Three studies showed an occurrence of PIGN without antibiotic use ranging from 1% to 13% with an MSD of 0.06 (−0.09–0.21). Our findings suggest that antimicrobial treatment for the initial infection may help diminish the development of PIGN. Although Streptococcus pyogenes infections are generally treated aggressively to prevent rheumatic fever, these findings may help further support the early treatment of bacterial infections to prevent postinfectious sequelae, especially as we consider other infectious etiologies of PIGN antimicrobial resistance.

Different antibiotic treatments for group A streptococcal pharyngitis

BACKGROUND

Antibiotics provide only modest benefit in treating sore throat, although their effectiveness increases in people with positive throat swabs for group A beta-haemolytic streptococci (GABHS). It is unclear which antibiotic is the best choice if antibiotics are indicated. This is an update of a review first published in 2010, and updated in 2013, 2016, and 2020.

OBJECTIVES

To assess the comparative efficacy of different antibiotics in: (a) alleviating symptoms (pain, fever); (b) shortening the duration of the illness; (c) preventing clinical relapse (i.e. recurrence of symptoms after initial resolution); and (d) preventing complications (suppurative complications, acute rheumatic fever, post-streptococcal glomerulonephritis). To assess the evidence on the comparative incidence of adverse effects and the risk-benefit of antibiotic treatment for streptococcal pharyngitis.

SEARCH METHODS

We searched the following databases up to 3 September 2020: CENTRAL (2020, Issue 8), MEDLINE Ovid (from 1946), Embase Elsevier (from 1974), and Web of Science Thomson Reuters (from 2010). We also searched clinical trial registers on 3 September 2020.

SELECTION CRITERIA

Randomised, double-blind trials comparing different antibiotics, and reporting at least one of the following: clinical cure, clinical relapse, or complications and/or adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened trials for inclusion and extracted data using standard methodological procedures as recommended by Cochrane. We assessed the risk of bias of included studies according to the methods outlined in the Cochrane Handbook for Systematic Reviews of Interventions, and used the GRADE approach to assess the overall certainty of the evidence for the outcomes. We have reported the intention-to-treat analysis, and also performed an analysis of evaluable participants to explore the robustness of the intention-to-treat results.

MAIN RESULTS

We included 19 trials reported in 18 publications (5839 randomised participants): six trials compared penicillin with cephalosporins; six compared penicillin with macrolides; three compared penicillin with carbacephem; one compared penicillin with sulphonamides; one compared clindamycin with ampicillin; and one compared azithromycin with amoxicillin in children. All participants had confirmed acute GABHS tonsillopharyngitis, and ages ranged from one month to 80 years. Nine trials included only, or predominantly, children. Most trials were conducted in an outpatient setting. Reporting of randomisation, allocation concealment, and blinding was poor in all trials. We downgraded the certainty of the evidence mainly due to lack of (or poor reporting of) randomisation or blinding, or both; heterogeneity; and wide confidence intervals. Cephalosporins versus penicillin We are uncertain if there is a difference in symptom resolution (at 2 to 15 days) for cephalosporins versus penicillin (odds ratio (OR) for absence of symptom resolution 0.79, 95% confidence interval (CI) 0.55 to 1.12; 5 trials; 2018 participants; low-certainty evidence). Results of the sensitivity analysis of evaluable participants differed (OR 0.51, 95% CI 0.27 to 0.97; 5 trials; 1660 participants; very low-certainty evidence). We are uncertain if clinical relapse may be lower for cephalosporins compared with penicillin (OR 0.55, 95% CI 0.30 to 0.99; number needed to treat for an additional beneficial outcome (NNTB) 50; 4 trials; 1386 participants; low-certainty evidence). Very low-certainty evidence showed no difference in reported adverse events. Macrolides versus penicillin We are uncertain if there is a difference between macrolides and penicillin for resolution of symptoms (OR 1.11, 95% CI 0.92 to 1.35; 6 trials; 1728 participants; low-certainty evidence). Sensitivity analysis of evaluable participants resulted in an OR of 0.79, 95% CI 0.57 to 1.09; 6 trials; 1159 participants). We are uncertain if clinical relapse may be different (OR 1.21, 95% CI 0.48 to 3.03; 6 trials; 802 participants; low-certainty evidence).  Azithromycin versus amoxicillin Based on one unpublished trial in children, we are uncertain if resolution of symptoms is better with azithromycin in a single dose versus amoxicillin for 10 days (OR 0.76, 95% CI 0.55 to 1.05; 1 trial; 673 participants; very low-certainty evidence). Sensitivity analysis for per-protocol analysis resulted in an OR of 0.29, 95% CI 0.11 to 0.73; 1 trial; 482 participants; very low-certainty evidence). We are also uncertain if there was a difference in relapse between groups (OR 0.88, 95% CI 0.43 to 1.82; 1 trial; 422 participants; very low-certainty evidence). Adverse events were more common with azithromycin compared to amoxicillin (OR 2.67, 95% CI 1.78 to 3.99; 1 trial; 673 participants; very low-certainty evidence). Carbacephem versus penicillin There is low-certainty evidence that compared with penicillin, carbacephem may provide better symptom resolution post-treatment in adults and children (OR 0.70, 95% CI 0.49 to 0.99; NNTB 14.3; 3 trials; 795 participants). Studies did not report on long-term complications, so it was unclear if any class of antibiotics was better in preventing serious but rare complications.  AUTHORS' CONCLUSIONS: We are uncertain if there are clinically relevant differences in symptom resolution when comparing cephalosporins and macrolides with penicillin in the treatment of GABHS tonsillopharyngitis. Low-certainty evidence in children suggests that carbacephem may be more effective than penicillin for symptom resolution. There is insufficient evidence to draw conclusions regarding the other comparisons in this review. Data on complications were too scarce to draw conclusions. These results do not demonstrate that other antibiotics are more effective than penicillin in the treatment of GABHS pharyngitis. All studies were conducted in high-income countries with a low risk of streptococcal complications, so there is a need for trials in low-income countries and Aboriginal communities, where the risk of complications remains high.

Short- vs. Long-Course Antibiotic Treatment for Acute Streptococcal Pharyngitis: Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

To evaluate the effectiveness of short courses of antibiotic therapy for patients with acute streptococcal pharyngitis.

METHODS

Randomized controlled trials comparing short-course antibiotic therapy (≤5 days) with long-course antibiotic therapy (≥7 days) for patients with streptococcal pharyngitis were included. Two primary outcomes: early clinical cure and early bacterial eradication.

RESULTS

Fifty randomized clinical trials were included. Overall, short-course antibiotic treatment was as effective as long-course antibiotic treatment for early clinical cure (odds ratio (OR) 0.85; 95% confidence interval (CI) 0.79 to 1.15). Subgroup analysis showed that short-course penicillin was less effective for early clinical cure (OR 0.43; 95% CI, 0.23 to 0.82) and bacteriological eradication (OR 0.34; 95% CI, 0.19 to 0.61) in comparison to long-course penicillin. Short-course macrolides were equally effective, compared to long-course penicillin. Finally, short-course cephalosporin was more effective for early clinical cure (OR 1.48; 95% CI, 1.11 to 1.96) and early microbiological cure (OR 1.60; 95% CI, 1.13 to 2.27) in comparison to long-course penicillin. In total, 1211 (17.7%) participants assigned to short-course antibiotic therapy, and 893 (12.3%) cases assigned to long-course, developed adverse events (OR 1.35; 95% CI, 1.08 to 1.68).

CONCLUSIONS

Macrolides and cephalosporins belong to the list of "Highest Priority Critically Important Antimicrobials"; hence, long-course penicillin V should remain as the first line antibiotic for the management of patients with streptococcal pharyngitis as far as the benefits of using these two types of antibiotics do not outweigh the harms of their unnecessary use.

Acute Pharyngitis Associated With Streptococcus dysgalactiae Subspecies equisimilis in Children

BACKGROUND AND OBJECTIVES

The importance of Streptococcus dysgalactiae subsp. equisimilis (SDSE) in causing sporadic pharyngitis in children remains controversial. The aims of this study were (1) to report the incidence and (2) to compare the epidemiologic and clinical features of patients with SDSE to those with Streptococcus pyogenes (SP).

METHODS

A prospective study was conducted on acute pharyngitis associated with SDSE in children over a 2-year period. SDSE was identified using a phenotypic method, M protein gene (emm) analysis and matrix-assisted laser desorption ionization-time of flight mass spectrometry. Patients with positive SDSE or SP cultures received cephalosporins for 5 days and were followed up. The emm genotyping and specific virulence genes analyses were performed.

RESULTS

From 3416 throat cultures, 67 isolates (2.0%) were identified as SDSE and 515 (15.1%) were identified as SP. The mean age of patients with SDSE (8.3 years) was older than those with SP (6.6 years; P < 0.01). There was minimal seasonal variation in the isolation rates of SDSE. The febrile patients' rates, gender distribution, cervical lymph node adenopathy rates, hospitalization rates, eradication and failure rates and the nonsuppurative sequelae between patients with SDSE and SP were similar. All SDSE isolates possessed important virulence genes. The emm genotyping of SDSE showed high strain diversity.

CONCLUSIONS

The incidence of acute pharyngitis associated with accurately identified SDSE was 2/15 of that with SP. Epidemiologic and clinical features of acute pharyngitis associated with SDSE are indistinguishable from those with SP, with the exception of age and seasonal variation.

Different antibiotic treatments for group A streptococcal pharyngitis

BACKGROUND

Antibiotics provide only modest benefit in treating sore throat, although effectiveness increases in participants with positive throat swabs for group A beta-haemolytic streptococci (GABHS). It is unclear which antibiotic is the best choice if antibiotics are indicated.

OBJECTIVES

To assess the evidence on the comparative efficacy of different antibiotics in: (a) alleviating symptoms (pain, fever); (b) shortening the duration of the illness; (c) preventing relapse; and (d) preventing complications (suppurative complications, acute rheumatic fever, post-streptococcal glomerulonephritis). To assess the evidence on the comparative incidence of adverse effects and the risk-benefit of antibiotic treatment for streptococcal pharyngitis.

SEARCH METHODS

We searched CENTRAL (2016, Issue 3), MEDLINE Ovid (1946 to March week 3, 2016), Embase Elsevier (1974 to March 2016), and Web of Science Thomson Reuters (2010 to March 2016). We also searched clinical trials registers.

SELECTION CRITERIA

Randomised, double-blind trials comparing different antibiotics and reporting at least one of the following: clinical cure, clinical relapse, or complications or adverse events, or both.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened trials for inclusion, and extracted data using standard methodological procedures as recommended by Cochrane. We assessed risk of bias of included studies according to the methods outlined in the Cochrane Handbook for Systematic Reviews of Interventions and used the GRADE tool to assess the overall quality of evidence for the outcomes.

MAIN RESULTS

We included 19 trials (5839 randomised participants); seven compared penicillin with cephalosporins, six compared penicillin with macrolides, three compared penicillin with carbacephem, one trial compared penicillin with sulphonamides, one trial compared clindamycin with ampicillin, and one trial compared azithromycin with amoxicillin in children. All included trials reported clinical outcomes. Reporting of randomisation, allocation concealment, and blinding was poor in all trials. The overall quality of the evidence assessed using the GRADE tool was low for the outcome 'resolution of symptoms' in the intention-to-treat (ITT) analysis and very low for the outcomes 'resolution of symptoms' of evaluable participants and for adverse events. We downgraded the quality of evidence mainly due to lack of (or poor reporting of) randomisation or blinding, or both, heterogeneity, and wide confidence intervals (CIs).There was a difference in symptom resolution in favour of cephalosporins compared with penicillin (evaluable patients analysis odds ratio (OR) for absence of resolution of symptoms 0.51, 95% CI 0.27 to 0.97; number needed to treat to benefit (NNTB) 20, N = 5, n = 1660; very low quality evidence). However, this was not statistically significant in the ITT analysis (OR 0.79, 95% CI 0.55 to 1.12; N = 5, n = 2018; low quality evidence). Clinical relapse was lower for cephalosporins compared with penicillin (OR 0.55, 95% CI 0.30 to 0.99; NNTB 50, N = 4, n = 1386; low quality evidence), but this was found only in adults (OR 0.42, 95% CI 0.20 to 0.88; NNTB 33, N = 2, n = 770). There were no differences between macrolides and penicillin for any of the outcomes. One unpublished trial in children found a better cure rate for azithromycin in a single dose compared to amoxicillin for 10 days (OR 0.29, 95% CI 0.11 to 0.73; NNTB 18, N = 1, n = 482), but there was no difference between the groups in ITT analysis (OR 0.76, 95% CI 0.55 to 1.05; N = 1, n = 673) or at long-term follow-up (evaluable patients analysis OR 0.88, 95% CI 0.43 to 1.82; N = 1, n = 422). Children experienced more adverse events with azithromycin compared to amoxicillin (OR 2.67, 95% CI 1.78 to 3.99; N = 1, n = 673). Compared with penicillin carbacephem showed better symptom resolution post-treatment in adults and children combined (ITT analysis OR 0.70, 95% CI 0.49 to 0.99; NNTB 14, N = 3, n = 795), and in the subgroup analysis of children (OR 0.57, 95% CI 0.33 to 0.99; NNTB 8, N = 1, n = 233), but not in the subgroup analysis of adults (OR 0.75, 95% CI 0.46 to 1.22, N = 2, n = 562). Children experienced more adverse events with macrolides compared with penicillin (OR 2.33, 95% CI 1.06 to 5.15; N = 1, n = 489). Studies did not report on long-term complications so it was unclear if any class of antibiotics was better in preventing serious but rare complications.

AUTHORS' CONCLUSIONS

There were no clinically relevant differences in symptom resolution when comparing cephalosporins and macrolides with penicillin in the treatment of GABHS tonsillopharyngitis. Limited evidence in adults suggests cephalosporins are more effective than penicillin for relapse, but the NNTB is high. Limited evidence in children suggests carbacephem is more effective than penicillin for symptom resolution. Data on complications are too scarce to draw conclusions. Based on these results and considering the low cost and absence of resistance, penicillin can still be regarded as a first choice treatment for both adults and children. All studies were in high-income countries with low risk of streptococcal complications, so there is need for trials in low-income countries and Aboriginal communities where risk of complications remains high.

Application of an enzyme-labeled antigen method for visualizing plasma cells producing antibodies against Strep A, a carbohydrate antigen of Streptococcus pyogenes, in recurrent tonsillitis

Streptococcus pyogenes is the main causative pathogen of recurrent tonsillitis. Histologically, lesions of recurrent tonsillitis contain numerous plasma cells. Strep A is an antigenic carbohydrate molecule on the cell wall of S. pyogenes. As expected, plasma cells in subjects with recurrent tonsillitis secrete antibodies against Strep A. The enzyme‐labeled antigen method is a novel histochemical technique that visualizes specific antibody‐producing cells in tissue sections by employing a biotin‐labeled antigen as a probe. The purpose of the present study was to visualize plasma cells producing antibodies reactive with Strep A in recurrent tonsillitis. Firstly, the lymph nodes of rats immunized with boiled S. pyogenes were paraformaldehyde‐fixed and specific plasma cells localized in frozen sections with biotinylated Strep A. Secondly, an enzyme‐labeled antigen method was used on human tonsil surgically removed from 12 patients with recurrent tonsillitis. S. pyogenes genomes were PCR‐detected in all 12 specimens. The emm genotypes belonged to emm12 in nine specimens and emm1 in three. Plasma cells producing anti‐Strep A antibodies were demonstrated in prefixed frozen sections of rat lymph nodes, 8/12 human specimens from patients with recurrent tonsillitis but not in two control tonsils. In human tonsils, Strep A‐reactive plasma cells were observed within the reticular squamous mucosa and just below the mucosa, and the specific antibodies belonged to either IgA or IgG classes. Our technique is effective in visualizing immunocytes producing specific antibodies against the bacterial carbohydrate antigen, and is thus a novel histochemical tool for analyzing immune reactions in infectious disorders.

Different antibiotic treatments for group A streptococcal pharyngitis

BACKGROUND

Antibiotics provide only modest benefit in treating sore throat, although effectiveness increases in participants with positive throat swabs for group A beta-haemolytic streptococci (GABHS). It is unclear which antibiotic is the best choice if antibiotics are indicated.

OBJECTIVES

To assess the evidence on the comparative efficacy of different antibiotics in: (a) alleviating symptoms (pain, fever); (b) shortening the duration of the illness; (c) preventing relapse; and (d) preventing complications (suppurative complications, acute rheumatic fever, post-streptococcal glomerulonephritis). To assess the evidence on the comparative incidence of adverse effects and the risk-benefit of antibiotic treatment for streptococcal pharyngitis.

SEARCH METHODS

We searched CENTRAL 2012, Issue 10, MEDLINE (1966 to October week 2, 2012), EMBASE (1974 to October 2012) and Web of Science (2010 to October 2012).

SELECTION CRITERIA

Randomised, double-blind trials comparing different antibiotics and reporting at least one of the following: clinical cure, clinical relapse, complications, adverse events.

DATA COLLECTION AND ANALYSIS

Two authors independently screened trials for inclusion and extracted data.

MAIN RESULTS

Seventeen trials (5352 participants) were included; 16 compared with penicillin (six with cephalosporins, six with macrolides, three with carbacephem and one with sulfonamides), one trial compared clindamycin and ampicillin. Randomisation reporting, allocation concealment and blinding were poor.There was no difference in symptom resolution between cephalosporins and penicillin (intention-to-treat (ITT) analysis; N = 5; n = 2018; odds ratio for absence of resolution of symptoms (OR) 0.79, 95% confidence interval (CI) 0.55 to 1.12). Clinical relapse was lower with cephalosporins (N = 4; n = 1386; OR 0.55, 95% CI 0.31 to 0.99; overall number needed to treat to benefit (NNTB) 50), but found only in adults (OR 0.42, 95% CI 0.20 to 0.88; NNTB 33). There were no differences between macrolides and penicillin. Carbacephem showed better symptom resolution post-treatment (N = 3; n = 795; OR 0.70, 95% CI 0.49 to 0.99; NNTB 14), but only in children (N = 2; n = 233; OR 0.57, 95% CI 0.33 to 0.99; NNTB 8.3). Children experienced more adverse events with macrolides (N = 1, n = 489; OR 2.33; 95% CI 1.06 to 5.15).

AUTHORS' CONCLUSIONS

Evidence is insufficient to show clinically meaningful differences between antibiotics for GABHS tonsillopharyngitis. Limited evidence in adults suggests cephalosporins are more effective than penicillin for relapse, but the NNTB is high. Limited evidence in children suggests carbacephem is more effective for symptom resolution. Data on complications are too scarce to draw conclusions. Based on these results and considering the low cost and absence of resistance, penicillin can still be recommended as first choice.

Short-term late-generation antibiotics versus longer term penicillin for acute streptococcal pharyngitis in children

BACKGROUND

The standard duration of treatment for children with acute group A beta hemolytic streptococcus (GABHS) pharyngitis with oral penicillin is 10 days. Shorter duration antibiotics may have comparable efficacy.

OBJECTIVES

To summarize the evidence regarding the efficacy of two to six days of newer oral antibiotics (short duration) compared to 10 days of oral penicillin (standard duration) in treating children with acute GABHS pharyngitis.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2012, Issue 3) which contains the Cochrane Acute Respiratory Infections Group's Specialized Register, MEDLINE (January 1966 to March week 3, 2012) and EMBASE (January 1990 to April 2012).

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing short duration oral antibiotics to standard duration oral penicillin in children aged 1 to 18 years with acute GABHS pharyngitis.

DATA COLLECTION AND ANALYSIS

Two review authors scanned the titles and abstracts of retrieved citations and applied the inclusion criteria. We retrieved included studies in full, and extracted data. Two review authors independently assessed trial quality.

MAIN RESULTS

We included 20 studies with 13,102 cases of acute GABHS pharyngitis. The updated search did not identify any new eligible studies; the majority of studies were at high risk of bias. However, the majority of the results were consistent. Compared to standard duration treatment, the short duration treatment studies had shorter periods of fever (mean difference (MD) -0.30 days, 95% confidence interval (CI) -0.45 to -0.14) and throat soreness (MD -0.50 days, 95% CI -0.78 to -0.22); lower risk of early clinical treatment failure (odds ratio (OR) 0.80, 95% CI 0.67 to 0.94); no significant difference in early bacteriological treatment failure (OR 1.08, 95% CI 0.97 to 1.20) or late clinical recurrence (OR 0.95, 95% CI 0.83 to 1.08). However, the overall risk of late bacteriological recurrence was worse in the short duration treatment studies (OR 1.31, 95% CI 1.16 to 1.48), although no significant differences were found when studies of low dose azithromycin (10 mg/kg) were eliminated (OR 1.06, 95% CI 0.92 to 1.22). Three studies reported long duration complications. Out of 8135 cases of acute GABHS pharyngitis, only six cases in the short duration treatment versus eight in the standard duration treatment developed long-term complications in the form of glomerulonephritis and acute rheumatic fever, with no statistically significant difference (OR 0.53, 95% CI 0.17 to 1.64).

AUTHORS' CONCLUSIONS

Three to six days of oral antibiotics had comparable efficacy compared to the standard duration 10-day course of oral penicillin in treating children with acute GABHS pharyngitis. . In areas where the prevalence of rheumatic heart disease is still high, our results must be interpreted with caution.

Streptococcal pharyngitis: a prospective study of compliance and complications

Background. Uncertainty exists concerning the necessity of 10-day antibiotic treatment of group A beta hemolytic streptococcus (GABHS) pharyngitis. Objective. To assess the incidence of GABHS recurrence and suppurative and nonsuppurative complications in relation to compliance. Methods. (Design). Prospective cohort observational study. (Subjects). 2,000 children aged 6 months to 18 years with sore throat and positive GABHS culture. (Main Outcome Measures). Recurrence of symptomatic culture positive GABHS pharyngitis, incidence of suppurative, and long-term, regional, nonsuppurative complications of GABHS pharyngitis, over a ten year period. Results. 213 (11%) of the children received no treatment. Most children received antibiotics for only 4-6 days (in correlation with the duration of fever, which in most cases lasted up to 3 days). Three hundred and six (15.3%) children had clinically diagnosed recurrent tonsillopharyngitis; 236 (12.3%) had positive GABHS findings within 10 to 14 days and thirty-four (1.7%) within 21-30 days after the index positive GABHS culture. The remaining 1.3% had no positive culture despite the clinical findings. Almost all recurrences [236 (11.6%)] occurred within 14 days and 156 (7.6%) in the fully treated group. The presence of fever during the first 3 days of the disease was the most significant predictor for recurrence. Other predictors were the age younger than 6 years and the presence of cervical lymphadenitis. No increase in the incidence of nonsuppurative or suppurative complications was noted during the 10-year follow-up period, compared to the past incidence of those complications in Israel. Conclusions. Our data suggests that the majority of children discontinue antibiotics for GABHS tonsillopharyngitis a day or two after the fever subsides. The incidence of complications in our study was not affected by this poor compliance.

Different antibiotic treatments for group A streptococcal pharyngitis

BACKGROUND

Antibiotics provide only modest benefit in treating sore throat, although effectiveness increases in participants with positive throat swabs for group A beta-haemolytic streptococci (GABHS). It is unclear which antibiotic is the best choice if antibiotics are indicated.

OBJECTIVES

We assessed the comparative efficacy of different antibiotics on clinical outcomes, relapse, complications and adverse events in GABHS tonsillopharyngitis.

SEARCH STRATEGY

We searched The Cochrane Library, Cochrane Central Register of Controlled Trials (CENTRAL 2010, Issue 3) which includes the Acute Respiratory Infections Group's Specialised Register, MEDLINE (1966 to July Week 4, 2010) and EMBASE (1974 to August 2010).

SELECTION CRITERIA

Randomised, double-blind trials comparing different antibiotics reporting at least one of the following: clinical cure, clinical relapse, complications, adverse events.

DATA COLLECTION AND ANALYSIS

Two authors independently screened trials for inclusion and extracted data.

MAIN RESULTS

Seventeen trials (5352 participants) were included; 16 compared with penicillin (six with cephalosporins, six with macrolides, three with carbacephem and one with sulfonamides), one trial compared clindamycin and ampicillin. Randomisation reporting, allocation concealment and blinding were poor.There was no difference in symptom resolution between cephalosporins and penicillin (intention-to-treat (ITT) analysis; N = 5; n = 2018; odds ratio for absence of resolution of symptoms (OR) 0.79, 95% confidence interval (CI) 0.55 to 1.12). Clinical relapse was lower with cephalosporins (N = 4; n = 1386; OR 0.55, 95% CI 0.31 to 0.99); overall number needed to treat to benefit (NNTB) 50), but found only in adults (OR 0.42, 95% CI 0.20 to 0.88; NNTB 33). There were no differences between macrolides and penicillin. Carbacephem showed better symptom resolution post-treatment (N = 3; n = 795; OR 0.70, 95% CI 0.49 to 0.99; NNTB 14), but only in children (N = 2; n = 233; OR 0.57, 95% CI 0.33 to 0.99; NNTB 8.3). Children experienced more adverse events with macrolides (N = 1, n = 489; OR 2.33; 95% CI 1.06 to 5.15).

AUTHORS' CONCLUSIONS

Evidence is insufficient for clinically meaningful differences between antibiotics for GABHS tonsillopharyngitis. Limited evidence in adults suggests cephalosporins are more effective than penicillin for relapse, but the NNTB is high. Limited evidence in children suggests carbacephem is more effective for symptom resolution. Data on complications are too scarce to draw conclusions. Based on these results and considering the low cost and absence of resistance, penicillin can still be recommended as first choice.

Comparative Study of 5-Day and 10-Day Cefditoren Pivoxil Treatments for Recurrent Group A beta-Hemolytic Streptococcus pharyngitis in Children

Efficacy of short-course therapy with cephalosporins for treatment of group A beta-hemolytic streptococcus (GABHS) pharyngitis is still controversial. Subjects were 226 children with a history of at least one episode of GABHS pharyngitis. Recurrence within the follow-up period (3 weeks after initiation of therapy) occurred in 7 of the 77 children in the 5-day treatment group and in 1 of the 149 children in the 10-day treatment group; the incidence of recurrence being significantly higher in the 5-day treatment group. Bacteriologic treatment failure (GABHS isolation without overt pharyngitis) at follow-up culture was observed in 7 of the 77 children in the 5-day treatment group and 17 of the 149 children in the 10-day treatment group. There was no statistical difference between the two groups. A 5-day course of oral cephalosporins is not always recommended for treatment of GABHS pharyngitis in children who have repeated episodes of pharyngitis.

Short versus standard duration antibiotic therapy for acute streptococcal pharyngitis in children

BACKGROUND

The standard duration of treatment for acute group A beta hemolytic streptococcus (GABHS) pharyngitis with oral penicillin is 10 days. Shorter duration antibiotics may have comparable efficacy.

OBJECTIVES

To summarize the evidence regarding the efficacy of two to six days of newer oral antibiotics (short duration) compared to 10 days of oral penicillin (standard duration) in treating children with acute GABHS pharyngitis.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, issue 4), which contains the Acute Respiratory Infections Group's Specialized Register; the Database of Abstracts of Reviews of Effects (DARE); MEDLINE (1966 to October 2007); OLDMEDLINE (1950 to December 1965); and EMBASE (January 1990 to November 2007).

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing short duration oral antibiotics to standard duration oral penicillin in children aged 1 to 18 years with acute GABHS pharyngitis.

DATA COLLECTION AND ANALYSIS

Two review authors scanned the titles and abstracts of retrieved citations and applied the inclusion criteria. We retrieved included studies in full and extracted data. Two review authors independently assessed trial quality.

MAIN RESULTS

Twenty studies were included with 13,102 cases of acute GABHS pharyngitis. Compared to standard duration treatment, the short duration treatment had shorter periods of fever (mean difference (MD) -0.30 days, 95% CI -0.45 to -0.14) and throat soreness (MD -0.50 days, 95% CI -0.78 to -0.22); lower risk of early clinical treatment failure (OR 0.80, 95% CI 0.67 to 0.94); no significant difference in early bacteriological treatment failure (OR 1.08, 95% CI 0.97 to 1.20), or late clinical recurrence (OR 0.95, 95% CI 0.83 to 1.08). However, the overall risk of late bacteriological recurrence was worse in the short duration treatment (OR 1.31, 95% CI 1.16 to 1.48), although no significant differences were found when studies of low dose azithromycin (10mg/kg) were eliminated (OR 1.06, 95% CI 0.92 to 1.22). Three studies reported long duration complications with no statistically significant difference (OR 0.53, 95% CI 0.17 to 1.64).

AUTHORS' CONCLUSIONS

Three to six days of oral antibiotics had comparable efficacy compared to the standard duration 10 day oral penicillin in treating children with acute GABHS pharyngitis. In countries with low rates of rheumatic fever, it appears safe and efficacious to treat children with acute GABHS pharyngitis with short duration antibiotics. In areas where the prevalence of rheumatic heart disease is still high, our results must be interpreted with caution.

[Antibiotic therapy in otorhinolaryngology]

First, the general principles for an antibiotic therapy are stated. The indications have to be well thought through. Frequent viral ENT infections, as well as numerous bacterial infections, should not be treated with antibiotics. Due to the current antibiotic sensitivity of the main ENT pathogens, the antibiotic choice for an empiric therapy is emphasized, and also the advantage of an optimized therapy based on the results of Gram stain (supercalculated empiric therapy) and an antibiogram (specific therapy). Pus characteristics may be the first step in diagnosing the pathogens. The degree of severity of an infection determines the oral or parenteral route of administration. As a rule, antibiotic therapy has to be checked after 2-3 days. The grouping of the different ENT infections with a similar spectrum of pathogens gives a better view of the therapeutic principles and reduces repetitions. The current recommendations for antibiotic treatment of numerous ENT infections with different degrees of severity are indicated. After the presentation of the appropriate antibiotics with their current spectrum of efficacy, the initial therapy, treatment in case of penicillin allergy, and of severe cases and complications or therapeutic failure are mentioned.

Two dosages of clarithromycin for five days, amoxicillin/clavulanate for five days or penicillin V for ten days in acute group A streptococcal tonsillopharyngitis

BACKGROUND

Short course antimicrobial therapy is suggested for group A streptococcal tonsillopharyngitis.

METHODS

The bacteriologic and clinical efficacies of clarithromycin [30 or 15 mg/kg/day twice daily (b.i.d.)] or amoxicillin/clavulanate (43.8/6.2 mg/kg/day b.i.d.) for 5 days or penicillin V (30 mg/kg/day 3 times a day) for 10 days were compared. In a randomized, open label, parallel group, multicenter study, 626 children (2-16 years old) with tonsillopharyngitis were enrolled; 537 were evaluable for efficacy. Follow-up evaluations were performed at 4-8 and 21-28 days after therapy.

RESULTS

At enrollment, 26% of the Streptococcus pyogenes isolates were clarithromycin-nonsusceptible. All regimens had an apparently similar clinical efficacy. The long term S. pyogenes eradication rates were 102 of 123 (83%) with amoxicillin/clavulanate and 88 of 114 (77%) with penicillin V. In the 30- and 15-mg/kg/day clarithromycin groups, eradication occurred in 71 of 86 (83%) and 59 of 80 (74%) of the clarithromycin-susceptible isolates (P = 0.33), and in 4 of 28 (14%) and 5 of 26 (19%) of the clarithromycin-resistant isolates, respectively (clarithromycin-susceptible versus -resistant, P < 0.0001). Both clarithromycin dosages were well-tolerated.

CONCLUSIONS

In group A streptococcal tonsillopharyngitis, 5 days of clarithromycin or amoxicillin/clavulanate treatment had clinical efficacy comparable with that of 10 days of penicillin V treatment; however, amoxicillin/clavulanate and penicillin V were bacteriologically more effective than clarithromycin because of its failure to eradicate the clarithromycin-resistant S. pyogenes isolates. The 5-day clarithromycin regimens are not recommended for treatment of streptococcal tonsillopharyngitis in areas where in vitro resistance of group A streptococci to clarithromycin is common.

Choroiditis, Pigment Epithelial Detachment, and Cystoid Macular Edema as Complications of Poststreptococcal Syndrome

PURPOSE

Two cases of poststreptococcal uveitis are presented. One patient developed nongranulomatous anterior uveitis (case 1). A second patient developed nongranulomatous anterior uveitis followed by granulomatous uveitis with concurrent choroiditis, retinal pigment epithelial detachment, and cystoid macular edema (case 2). Current concepts regarding the pathogenesis of poststreptococcal syndrome and its ocular sequelae are also discussed.

CASE REPORTS

Case 1: A 31-year-old female patient presented with bilateral nongranulomatous uveitis after a recent onset of sore throat. A past diagnosis of rheumatic fever was revealed during acquisition of the patient's history. Blood chemistry analysis indicated elevated anti-streptolysin O antibody titers as the only significant elevated result. Case 2: A 33-year-old female presented initially with bilateral nongranulomatous uveitis. A history of recurrent sore throat was reported. Blood chemistry analysis revealed elevated anti-streptolysin O antibody titers only. "Mutton fat" keratic precipitates eventually developed; however, the bilateral uveitis resolved after topical cycloplegic and corticosteroid treatment. An anterior granulomatous uveitis with concurrent choroiditis, retinal pigment epithelial detachment, and cystoid macular edema ensued during a recurrent episode. Blood chemistry analysis was unremarkable at that time.

CONCLUSIONS

: Anterior nongranulomatous/granulomatous and posterior uveitis should be considered clinical manifestations of poststreptococcal syndrome in patients with a clinical history and/or serological evidence indicating possible past streptococcal infection. A variation of host-genetic-predisposed immune response, the patient's human leukocyte antigen haplotype, pathogen virulence, and/or deposition location of immune circulating complexes may give rise to the diverse spectrum of clinical ocular sequelae in poststreptococcal syndrome. Poststreptococcal uveitis may comprise a similar immunologic pathogenesis to that of acute rheumatic fever, acute glomerulonephritis, and other autoimmune diseases.

Streptococcal-A Tonsillopharyngitis: A 5-Day Course of Cefuroxime Axetil versus a 10-Day Course of Penicillin V

BACKGROUND

The recommended duration of antibiotic treatment of tonsillopharyngitis caused by group A beta-hemolytic streptococci (GABHS) with penicillin V (PenV) is mostly 10 days. However, compliance with 10-day courses is bad. Shorter therapeutic courses are necessary, especially in young children.

METHODS

In a prospective, randomized, multi-center study, children aged 1-17 years with acute tonsillopharyngitis and a positive culture for GABHS were treated with cefuroxime axetil (CAE) 20 mg/kg/day (max. 500 mg) b.i.d. for 5 days or with PenV 50,000 IU/kg (30 mg/kg) t.i.d. for 10 days. Patients were evaluated for clinical efficacy 2-4 and 7-9 days after the end of therapy. Throat swabs were taken 2-4 days after the end of therapy and at the first follow-up visit. Follow-up visits were carried out 7-8 weeks, 6 months and 12 months after study inclusion.

RESULTS

1,952 patients (CAE for 5 days, 496 patients/PenV for 10 days, 1,456 patients) could be included in the intent-to-treat analysis. Two to 4 days after completion of the treatment course, the bacteriological eradication in group A (1-5 years) and group B (6-17 years) was 90.52 and 89.53% (CAE) vs. 84.13 and 84.20% (PenV), respectively; p = 0.0172; 0.0382; clinical success was 98.30% (CAE) versus 93.25% (PenV), p = 0.0017. Recurrent infections were significantly higher in younger children (group A) under both treatment regimens. Poststreptococcal sequelae (glomerulonephritis) were observed in only 1 case, in the PenV group.

CONCLUSIONS

CAE b.i.d. for 5 days was at least as effective as PenV t.i.d. for 10 days. Incountries with a low incidence of rheumatic fever, CAE for 5 days can be recommended for the therapy of tonsillopharyngitis due to GABHS - also in young children.

Short-course antimicrobial therapy of respiratory tract infections

Accumulating evidence suggests that short-course (</=5 days, </=3 days for azithromycin) antimicrobial therapy may be at least as effective as and, in some cases, may be more effective than traditional longer (10- to 14-day) therapies. In group A beta-haemolytic streptococcal tonsillopharyngitis, short-course therapy with 6 days of amoxicillin, 4-5 days of a variety of cephalosporins and 5 days of clarithromycin modified-release and telithromycin are all reasonable alternatives to traditional 10-day penicillin therapy. Short-course (i.e. 3-day) azithromycin therapy is not recommended because of suboptimal clinical and bacteriological results compared with penicillin therapy, unless the dosage is doubled from 10 to 20 mg/kg/day for all 3 days. In uncomplicated acute suppurative otitis media, single-dose intramuscular ceftriaxone or 3- to 5-day short-course oral antimicrobial therapy should be effective in the majority (>/=80%) of patients. However, more research is clearly needed in the subpopulations of children <2 years of age and in those with unresponsive/recurrent disease, since short-course therapy may not be successful in the majority of these patients. In sinusitis, most short-course therapy data have involved maxillary disease in adult patients. Regimens have included 3 days of azithromycin or cotrimoxazole (trimethoprim/sulfamethoxazole) or 5 days of cefpodoxime, telithromycin, gatifloxacin, gemifloxacin or amoxicillin/clavulanic acid. Preliminary results are encouraging but more study is clearly needed, especially in the paediatric population. In acute bacterial exacerbations of chronic bronchitis, short-course therapy with a variety of cephalosporins, second-generation fluoroquinolones and advanced generation macrolides/azalides/ketolides are all reasonable alternatives to traditional 7- to 14-day therapies. Cost containment in antimicrobial therapy should involve consideration of short-course therapy in the management of the most common types of respiratory tract infections.

Defining the optimum treatment regimen for azithromycin in acute tonsillopharyngitis

Pharyngitis is one of the most common infectious diseases affecting children. Group A streptococci are the leading bacterial cause of pharyngitis in children and adults. Because inappropriate antibiotic treatment for pharyngitis is becoming a major issue, only true group A beta-hemolytic streptococcus (GABHS) infections, proven by rapid antigen test or culture, should be treated with antibiotics. GABHS pharyngitis is often a mild and self-limiting infection in the absence of antimicrobial therapy. However, antimicrobial treatment must be administered to eradicate the pathogen from the throat, limit the spread of the infection and prevent possible progression to rheumatic fever, suppurative disease or toxin-mediated complications. Penicillin V for 10 days is the standard therapy and is effective in the management of GABHS pharyngitis. However, there are drawbacks to penicillin V therapy, including the length of the dosing regimen, which are leading to decreasing penicillin prescription rates in many countries. In addition bacteriologic treatment failures have been documented in up to 35% of GABHS patients treated with penicillin V, particularly in children <6 years old. A number of mechanisms may be responsible for these failures, but poor compliance with the standard 10-day penicillin treatment is likely to be a major factor. There is growing evidence to suggest that children with GABHS pharyngitis can be effectively treated with non-penicillin V antibiotics, which have the advantage of simpler and shorter dosing regimens compared with penicillin V. Among the antibiotics that have been tested clinically, azithromycin is the most widely studied. A total dose of 60 mg/kg azithromycin, given either as 12 mg/kg once daily for 5 days or 20 mg/kg once daily for 3 days, provides the best rate of GABHS eradication. Thus a total dose of 60 mg/kg azithromycin given during 3 or 5 days constitutes an alternative treatment to standard penicillin therapy in cases of penicillin hypersensitivity, when patient nonadherence to a 10-day penicillin regimen is suspected or for patients who fail therapy with a beta-lactam.

Short-Course Therapy for Acute Sinusitis

This review examines the issues surrounding short-course antibiotic therapy of acute sinusitis. Acute bacterial sinusitis is a common community-acquired infection defined as inflammation of one or more paranasal sinuses, most often the maxillary sinus. It is estimated that 0.5-5% of colds are complicated by acute sinusitis. Up to 1 in 20 upper respiratory tract infections is complicated by bacterial sinusitis, most often caused by Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Staphylococcus aureus. Early diagnosis and appropriate antibiotic therapy, in combination with agents that relieve nasal congestion, are important factors in preventing suppurative complications. Left untreated, it could lead to the development of chronic sinusitis or epidural or subdural empyema, brain abscess, or cavernosus sinus thrombosis. Isolation of the causal organism is often lacking in the community setting. Empiric antibiotic therapy should provide adequate coverage against the most important pathogens. Guidelines from different specialist societies based on current scientific knowledge are helpful in making the decision on which drug to use. Recommendations for duration of treatment of acute sinusitis are inconsistent between different guidelines but usually a 10- to 14-day treatment course is recommended.Recognition that the 10- to 14-day duration of therapy is not derived from a strong scientific or medical rationale has led some clinicians to call for shortening the duration of antibiotic therapy for patients with upper respiratory tract infections. Accumulating evidence suggests that short-course (< or =5 days) antibiotic therapy may have equivalent or superior efficacy compared with traditional longer (10-14 days) therapies and offers a number of advantages. Results of a number of clinical trials investigating 5-day therapy with oral cephalosporins, new quinolones or ketolides in acute (presumed) bacterial sinusitis in comparison with traditional 10-day treatment courses have been published demonstrating equivalent efficacy of 5-day and 10-day regimens. The evidence reviewed in this article strongly supports reduction of the traditional 10-day course of antibacterial therapy to a 5-day course for uncomplicated acute maxillary sinusitis in adults. Further research related to the duration of antibacterial therapy for sinusitis is needed in children and in adult patients with frontal, ethmoidal and sphenoidal sinusitis.

Short-course antimicrobial therapy of streptococcal pharyngitis

While penicillin administered orally or intramuscularly is the least expensive course of pharyngitis treatment, there are many limitations to its use. These include the need for extended treatment (i.e., 10 days) and poor palatability of its liquid formulation and an alarming increase in the rates of failure with standard doses of either IM or oral penicillin. Increasing rates of beta-lactamase-producing normal flora and eradication of protective alpha-streptococci may also play a role in penicillin treatment failure. Thus practitioners may consider switching to amoxicillin in higher doses (up to 40 to 60 mg/kg/day divided twice daily, maximum dose 1 gram twice daily) as first-line therapy (Figure 1), similar to what we have done for acute otitis media. Five-day short-course treatment with cefdinir or cefpodoxime may be suitable alternatives, especially in patients with penicillin hypersensitivity (not anaphylaxis). Concerns with higher costs of these second-line agents and potential for resistance must be balanced with concerns for patient adherence with penicillin treatment and the recent increasing rate of penicillin failures. In light of recent reports regarding the high rate of failure with azithromycin and increasing macrolide resistance, clinicians should prescribe standard doses of this drug for 5 days with caution.

[Appropriateness of treatment of acute pharyngotonsillitis according to the scientific evidence]

OBJECTIVE

To evaluate the appropriateness of antibiotic prescriptions in children with acute pharyngotonsillitis.

METHODS

A descriptive study was performed in a series of pediatric patients diagnosed with acute pharyngotonsillitis in the emergency rooms of 11 Spanish hospitals. The appropriateness of antibiotic prescriptions was assessed by comparing our clinical practice in the use of antibiotics for pharyngotonsillitis with consensus guidelines developed for this study.

RESULTS

We collected data from 1716 patients with acute pharyngotonsillitis. Antibiotics were prescribed in 80.9 %, mainly according to empirical criteria. The most commonly used antibiotics were amoxicillin (36 %), amoxicillin-clavulanate (22.5 %), cefixime (6.6 %), azithromycin (5.8 %) and cefuroxime (5.2 %). A total of 39.5 % of the patients were aged less than 3 years, of which 75.9 % were treated empirically. Of the prescribed treatments, 22.8 % were considered as the treatment of choice; 22.4 % as alternatives and 54.8 % as inappropriate.

CONCLUSIONS

Antibiotic treatment was prescribed in most of the cases of pharyngotonsillitis and nearly always according to empirical criteria. The number of antibiotic prescriptions was far higher than the expected cases of bacterial pharyngotonsillitis and, in many cases, the antibiotic prescriptions were inappropriate.

Epidemiology and virulence gene expression of intracellular group A streptococci in tonsils of recurrently infected adults

Intracellularly persistent group A streptococci (GAS, Streptococcus pyogenes) have been associated with recurrent tonsillopharyngitis and antibiotic treatment failure. As a supplementation of the published in vitro data, conventional bacteriology and molecular epidemiology was performed on material from 29 adult patients of a German army hospital with anamnestic signs of recurrent tonsillopharyngitis. Pre-surgery tonsil swabs and the surgically removed tonsils were examined with respect to growth of aerobic bacteria in absence and presence of antibiotics with exclusively extracellular activity. Under such antibiotic selection, Staphylococcus aureus and GAS were cultured from specimens of 13 and 3 patients, respectively. In every material GAS-positive by culture methods, the intracellular location of the penicillin-susceptible GAS isolates was confirmed by immunohistologic examination of tonsillar sections using a GAS-specific IgG antibody. The three intracellular GAS isolates were typed by emm gene sequencing and could be associated to types M6 and M49 (two isolates). The bacteria were serially passaged on sheep blood agar, and semiquantitative mRNA analysis from virulence genes was performed using bacteria of the 4th and 25th passage after isolation. An M-type-specific pattern of virulence gene expression and different gene expression levels in relation to the passage number were observed.

Virulence factor regulation and regulatory networks in Streptococcus pyogenes and their impact on pathogen-host interactions

Streptococcus pyogenes (group A streptococcus, GAS) is a very important human pathogen with remarkable adaptation capabilities. Survival within the harsh host surroundings requires sensing potential on the bacterial side, which leads in particular to coordinately regulated virulence factor expression. GAS 'stand-alone' response regulators (RRs) and two-component signal transduction systems (TCSs) link the signals from the host environment with adaptive responses of the bacterial cell. Numerous putative regulatory systems emerged from GAS genome sequences. Only three RRs [Mga, RofA-like protein (RALP) and Rgg/RopB] and three TCSs (CsrRS/CovRS, FasBCAX and Ihk/Irr) have been studied in some detail with respect to their growth-phase-dependent activity and their influence on GAS-host cell interaction. In particular, the Mga-, RALP- and Rgg/RopB-regulated pathways display interconnected activities that appear to influence GAS colonization, persistence and spreading mechanisms, in a growth-phase-related fashion. Here, we have summarized our current knowledge about these RRs and TCSs to highlight the questions that should be addressed in future research on GAS pathogenicity.

Antibacterial therapy for acute group a streptococcal pharyngotonsillitis: short-course versus traditional 10-day oral regimens

The objective of this review is to examine the use of short-course antibacterial therapy of group A beta-hemolytic streptococcal (GABHS) pharyngotonsillitis, compared with traditional 10-day therapy. In preparing this paper we reviewed the medical literature of studies comparing 10 days of penicillin with shorter courses of antibacterial therapy. Short-course therapy of 6 days of amoxicillin, 4 to 5 days of cephalosporins, and 5 days of azithromycin was found to be as, or more effective than traditional 10-day penicillin therapy. The benefits of short-course therapy include superior compliance and adherence, lower incidence of adverse effects, less effect on the bacterial flora, improved patient and parent satisfaction, and lower drug costs. In conclusion, short courses of amoxicillin, cephalosporins, and macrolides provide superior or equal efficacy to a 10-day course of penicillin therapy in the treatment of GABHS pharyngotonsillitis.

The use and resistance to antibiotics in the community

The frequency of resistance to antibiotics among common community-acquired pathogens, and the number of drugs to which they are resistant have been increasing worldwide. The relationship between antibiotic usage and resistance is strongly supported by data from several studies. Countries with the highest per capita antibiotic consumption have the highest resistance. The emergence of penicillin-resistant Streptococcus pneumoniae is related to high consumption of antibiotics in general, as well as to increased use of aminopenicillins and/or probably to wider use of oral cephalosporins. Increased consumption of macrolides, especially the long-acting ones, correlates significantly with the level of macrolide resistance of group A streptococci and S. pneumoniae while increased use of oral cephalosporins might be associated with the increase of beta-lactamase-producing strains of Moraxella catarrhalis. Trimethoprim/sulphamethoxazole resistance is strongly associated with resistance to penicillin. A rise in consumption of fluoroquinolones is consonant with a higher rate of resistance to quinolones of S. pneumoniae, Escherichia coli and other Gram-negative bacteria. Paediatric bacterial isolates are more often resistant to various antimicrobial agents than isolates from adult patients; this higher resistance rate may be due to more frequent antimicrobial treatments in children, and extensive child to child transmission. Reliable data on antimicrobial consumption and resistance should form a basis for national policies devised to reduce the resistance of microorganisms to antibiotics.

Macrolide-resistant Streptococcus pneumoniae and Streptococcus pyogenes in the pediatric population in Germany during 2000-2001

In a nationwide study in Germany covering 13 clinical microbiology laboratories, a total of 307 Streptococcus pyogenes (mainly pharyngitis) and 333 Streptococcus pneumoniae (respiratory tract infections) strains were collected from outpatients less than 16 years of age. The MICs of penicillin G, amoxicillin, cefotaxime, erythromycin A, clindamycin, levofloxacin, and telithromycin were determined by the microdilution method. In S. pyogenes isolates, resistance rates were as follows: penicillin, 0%; erythromycin A, 13.7%; and levofloxacin, 0%. Telithromycin showed good activity against S. pyogenes isolates (MIC(90) = 0.25 micro g/ml; MIC range, 0.016 to 16 micro g/ml). Three strains were found to be telithromycin-resistant (MIC >/= 4 micro g/ml). Erythromycin-resistant strains were characterized for the underlying resistance genotype, with 40.5% having the efflux type mef(A), 38.1% having the erm(A), and 9.5% having the erm(B) genotypes. emm typing of macrolide-resistant S. pyogenes isolates showed emm types 4 (45.2%), 77 (26.2%), and 12 (11.9%) to be predominant. In S. pneumoniae, resistance rates were as follows: penicillin intermediate, 7.5%; penicillin resistant, 0%; erythromycin A, 17.4%; and levofloxacin, 0%. Telithromycin was highly active against pneumococcal isolates (MIC(90) </= 0.016 micro g/ml; range, 0.016 to 0.5 micro g/ml). The overall resistance profile of streptococcal respiratory tract isolates is still favorable, but macrolide resistance is of growing concern in Germany.

Comparative efficacy and safety of 5-day cefaclor and 10-day amoxycillin treatment of group A streptococcal pharyngitis in children

A total of 384 children with group A beta-haemolytic streptococcal (GABHS) pharyngitis were randomized to receive either 40 mg/kg/day of cefaclor in two doses for 5 days (192 patients), or 40 mg/kg/day of amoxycillin in three doses for 10 days (192 patients). The signs and symptoms of pharyngitis were recorded and throat cultures were obtained at presentation and on days 6-7, 11-15, 16-20 and 28-35. Patient compliance was significantly higher in the children treated with cefaclor (100 vs. 95.1%; P = 0.003). At the end of follow-up, the percentage of clinical success was 91.4% for cefaclor and 91.9% for amoxycillin (P = 0.974); bacteriological success was obtained in 85.7 and 89.6% children (P = 0.348), respectively. Both treatments were well-tolerated with adverse event rates of 8.3% in the cefaclor group and 9.4% in the amoxcillin group (P = 0.857). Our study shows that five days' treatment with cefaclor is as effective and safe as the conventional 10-day course of amoxycillin in the treatment of GABHS pharyngitis, but compliance seems to be significantly greater.

High prevalence of erythromycin resistance of Streptococcus pyogenes in Greek children

BACKGROUND

Macrolide resistance among Streptococcus pyogenes strains is increasing in many European countries. Greece was not considered a country with high prevalence of macrolide-resistant S. pyogenes strains, and until now the genetic mechanism of resistance was unknown.

METHODS

During the 25-month period from December, 1998, to December, 2000, pharyngeal cultures for S. pyogenes were performed on 743 Greek children with the clinical diagnosis of pharyngitis. The children were 1 to 16 years old (median age, 7 years) and were living in Central and Southern Greece. S. pyogenes isolates were tested for their susceptibility to erythromycin, clarithromycin, azithromycin, clindamycin, penicillin G, amoxicillin/clavulanate and cefprozil. The erythromycin-resistant isolates were further studied for their genetic mechanism of resistance by means of PCR.

RESULTS

Of a total of 275 S. pyogenes isolates recovered, 105 (38%) were erythromycin-resistant (MIC > or = 1 microgram/ml) [corrected], with 54, 45 and 1% of them carrying mef(A), erm(A) [subclass erm(TR)] and erm(B) gene, respectively. The prevalence of erythromycin-resistant strains was 29 and 42% during the time periods December, 1998, to December, 1999, and January, 2000, to December, 2000, respectively. All erythromycin-resistant isolates were also resistant to clarithromycin and azithromycin. The isolates carrying the erm(A) gene were inducibly resistant to clindamycin. The 275 S. pyogenes isolates had ceprozil MICs < or = 0.032 microgram/ml.

CONCLUSIONS

The current high (38%) prevalence of erythromycin-resistant S. pyogenes in Central and Southern Greece requires continuous surveillance and careful antibiotic policy.

[Treatment of acute group A beta-hemolytic streptococcal tonsillitis in children with a 5-day course of josamycin]

MATERIAL AND METHODS

In this randomized open study, 325 children aged two to 15 years with acute tonsillitis and a positive test of GA beta H streptococcal antigen were treated with josamycin 50 mg.kg-1.day-1 b.i.d for 5 days, or penicillin 50,000 to 100,000 IU/day t.i.d for 10 days. Clinical assessments and throat cultures for GA beta HS isolation were performed at the inclusion visit (V1), at the end of treatment visit (V2: day 12 for all patients) and at the follow-up visit (V3: day 30). In case of positive GA beta HS culture, the bacterial DNA by RFLP was performed to differentiate between the persistence (presence of original strain at V2), relapse (eradication at V2 and acquisition of same strain at V3) and reinfection (eradication at V2 and acquisition of different strain at V3).

RESULTS

Two hundred and twenty-three patients were included in the bacteriological and clinical criteria per protocol analysis. At V2, eradication rates were comparable: 82% in josamycin and 80% in penicillin patients; clinical cure rates were 90% and 89%. At V3, relapse of GAS assessed only on clinically and bacteriologically cured patients at V2 occurred in 12% of josamycin patients and 12.8% of penicillin patients. Tolerance was good; 14% and 10% of josamycin and penicillin patients respectively experienced an adverse event.

CONCLUSION

In this non-inferiority study, the efficacy of a 5-day course of josamycin is comparable to reference treatment in GA beta HS tonsillitis in children.