Randomized, single-blinded comparative study of the efficacy of amoxicillin (40 mg/kg/day) versus standard-dose penicillin V in the treatment of group A streptococcal pharyngitis in children

Rheumatic heart disease anno 2020: Impacts of gender and migration on epidemiology and management

BACKGROUND

The epidemiology and management of diseases can be influenced by social demographic factors. Gender and migration are among these factors.

METHODS

We aimed at reviewing the impacts of gender and migration on rheumatic heart disease (RHD) epidemiology and management by a nonsystematic literature review of published studies on RHD worldwide. Our PubMed search terms included RHD pathophysiology, diagnosis, complications, management or prevention, combined with words 'rheumatic mitral stenosis (MS)', 'outcomes after percutaneous balloon mitral valvuloplasty (PBMV)', 'gender or sex difference' and 'migration'. The reporting of this study conforms to SANRA (the Scale for Assessment of Narrative Review Articles) guidelines.

RESULTS

We retrieved eight studies about the impact of sex on outcomes after PBMV. All of these studies showed a female predominance for RHD. Two studies showed that there is no impact, three studies showed female sex as a predictor of poor outcomes, and the other three showed male sex a predictor of poor outcomes. Although RHD is reported to be eradicated in the developed countries, 2.1% of refugees recently screened for RHD in Italy were found to have subclinical RHD. This prevalence is similar to those found in India (2.0%), Cambodia (2.2%) and Mozambique (3%).

CONCLUSIONS

There are contradicting results for outcomes after PBMV between males and females. It is not clear whether sex difference plays a role in pathophysiology, diagnosis, management and prognosis of MS. Migration has impacts on epidemiology and management of RHD. Further studies are required in these two fields to explore their relationship to RHD.

Acute rheumatic fever

Acute rheumatic fever is caused by an autoimmune response to throat infection with Streptococcus pyogenes. Cardiac involvement during acute rheumatic fever can result in rheumatic heart disease, which can cause heart failure and premature mortality. Poverty and household overcrowding are associated with an increased prevalence of acute rheumatic fever and rheumatic heart disease, both of which remain a public health problem in many low-income countries. Control efforts are hampered by the scarcity of accurate data on disease burden, and effective approaches to diagnosis, prevention, and treatment. The diagnosis of acute rheumatic fever is entirely clinical, without any laboratory gold standard, and no treatments have been shown to reduce progression to rheumatic heart disease. Prevention mainly relies on the prompt recognition and treatment of streptococcal pharyngitis, and avoidance of recurrent infection using long-term antibiotics. But evidence for the effectiveness of either approach is not strong. High-quality research is urgently needed to guide efforts to reduce acute rheumatic fever incidence and prevent progression to rheumatic heart disease.

[Treatment of streptococcal tonsillitis with once-a-day amoxicillin: a meta-analysis]

INTRODUCTION

The objective of this systematic review is to determine if the treatment of streptococcal pharyngitis with a daily dose of amoxicillin is similar in effectiveness to other dosing schedules (every 6, 8 or 12 hours) of the same antibiotic or penicillin V.

MATERIAL AND METHODS

Randomised clinical trials (RCT) comparing amoxicillin (one dose per day) compared to other dosages of amoxicillin (every 8-12 hours) or penicillin V (every 6, 8 or 12 hours). Search databases consulted: Medline, Central, EMBASE and Google Scholar. The results were combined using the risk difference (RD). We measured the effectiveness of each treatment with a negative throat culture on the 14-21th day, being previously positive to group A Streptococcus (under a non-inferiority hypothesis, where the upper limit of the 95% confidence interval [95% CI] of the DR does not exceed 10%) and clinical failure on days 10-21. The results were combined according to a fixed effects model or random depending on whether or not there was heterogeneity.

RESULTS

Four RCT met the selection criteria with 1,314 participants (657 received amoxicillin once per day, and 657 received other antibiotics or dosages): a) any positive culture for Streptococcus (14-21st day, 4 RCTs): DR: -0.5% (95% CI: -5.1% to 4.2%; b) persistence of the same serotype (14-21st day, 3 RCT): DR: 0.32% (95% CI: -3.1% to 3.7%; c) clinical failure (2 RCT): DR: 1.7% (95% CI: -1.9% to 5.4%; d) adverse effects (4 RCT): DR: -0.39% (95% CI: -1.5% to 6.8%). There were no statistically significant differences in any comparisons.

CONCLUSIONS

Amoxicillin, administered once daily is not inferior to other dosages of the same antibiotic or penicillin V. These results are important because they may facilitate compliance.

Upper Respiratory Infections and Acute Bronchitis

Upper respiratory infections include the following: uncomplicated upper respiratory infections also known as the “common cold,” acute otitis media, pharyngitis/tonsillitis, and acute sinusitis. These conditions, along with acute bronchitis, are very common illnesses that are commonly seen in outpatient settings and are widely treated with antibiotics. In fact, these conditions are the primary indications for outpatient antibiotic prescriptions. These conditions tend to have overlapping clinical characteristics yet evidence regarding the utility of antimicrobial treatments varies across conditions.

Frequency of symptomatic relapses of group A beta-hemolytic streptococcal tonsillopharyngitis in children from 4 pediatric practices following penicillin, amoxicillin, and cephalosporin antibiotic treatment

The objective was to determine the frequency of early symptomatic relapses following antibiotic treatment for group A beta-hemolytic streptococcal (GABHS) tonsillopharyngitis in children from Rochester, New York; Houston, Texas; Spokane, Washington; and Los Angeles, California (2004--2006). The study included 4278 patients. The proportion with a bacteriologic relapse of GABHS tonsillopharyngitis within 1 to 5 days of completing a 10-day treatment course was 8% (penicillin and bicillin), 6% (amoxicillin), 2% (first-generation cephalosporin), and 1% (second-generation and third-generation cephalosporin; P = .0001); symptomatic relapses occurred within 6 to 20 days after completion of therapy in 16%, 14%, 9%, and 7% of cases (P = .0001). Cases from New York and Washington had higher penicillin or amoxicillin failure rates than cases from Texas and California. The frequency of symptomatic relapses of GABHS tonsillopharyngitis, therefore, differs according to the antibiotic treatment selected; the trend for such relapses being penicillin or amoxicillin > cephalosporins although geographic differences may occur.

Pharyngitis and epiglottitis

Acute pharyngitis is one of the most common illnesses for which patients visit primary care physicians. Most cases are of viral origin, and with few exceptions these illnesses are both benign and self-limited. The most important bacterial cause is the beta-hemolytic group A streptococcus. There are other uncommon or rare types of pharyngitis. For some of these treatment is required or available, and some may be life threatening. Among those discussed in this article are diphtheria, gonorrhea, HIV infection, peritonsillar abscess, and epiglottitis.

Treatment of streptococcal pharyngitis with once-daily compared with twice-daily amoxicillin: a noninferiority trial

BACKGROUND

Two relatively small previous studies comparing once-daily amoxicillin with conventional therapy for group A streptococcal (GAS) pharyngitis reported similar rates of bacteriologic success for each treatment group. The purpose of this study was to further evaluate once-daily amoxicillin for GAS pharyngitis in a larger study.

METHODS

In a single pediatric practice, from October through May for 2 consecutive years (2001-2003), we recruited children 3 to 18 years of age who had symptoms and signs suggestive of GAS pharyngitis. Patients with a positive rapid test for GAS were stratified by weight (<40 kg or >or=40 kg) and then randomly assigned to receive once-daily (750 mg or 1000 mg) or twice-daily (2 doses of 375 mg or 500 mg) amoxicillin for 10 days. We determined bacteriologic failure rates for GAS in the pharynx from subsequent swabs taken at 14 to 21 (visit 2) and 28 to 35 (visit 3) days after treatment initiation. We conducted a randomized, controlled, investigator-blinded, noninferiority trial to evaluate whether amoxicillin given once daily would have a bacteriologic failure rate no worse than that of amoxicillin given twice daily within a prespecified margin of 10%. GAS isolates were characterized to distinguish bacteriologic failures from new acquisitions. Adverse events were described and adherence was evaluated by review of returned daily logs and dosage bottles.

RESULTS

Of 2139 potential study patients during the 2-year period, we enrolled 652 patients, 326 into each treatment group. Children in the 2 groups were comparable with respect to all demographic and clinical characteristics except that children <40 kg more often presented with rash in each treatment group. At visit 2, failure rates were 20.1% (59 of 294) for the once-daily group and 15.5% (46 of 296) for the twice-daily group (difference, 4.53%; 90% confidence interval [CI], -0.6 to 9.7). At visit 3, failure rates were 2.8% (6 of 216) for the once-daily group and 7.1% (16 of 225) for the twice-daily group (difference, -4.33; 90% CI, -7.7 to -1.0). Gastrointestinal and other adverse events occurred in the once-daily treatment group with a frequency comparable to that in the twice-daily treatment group. Presumed allergic reactions occurred in 0.9% (6 of 635). More than 95% (516 of 541) of patients complied with 10 days of therapy with no significant differences between groups.

CONCLUSIONS

We conclude that amoxicillin given once daily is not inferior to amoxicillin given twice daily. Gastrointestinal and other events did not occur significantly more often in the once-daily treatment group. From the data in this large, investigator-blinded, controlled study, once-daily amoxicillin appears to be a suitable regimen for treatment of GAS pharyngitis.

Pathogen shifts and changing cure rates for otitis media and tonsillopharyngitis

Pneumococcal conjugate vaccine use has caused a decrease in the incidence of recurrent and refractory acute otitis media in the United States and a shift in the predominant pathogens. Now Haemophilus influenzae is the most commonly isolated organism (about 60% of the total), and more than half the strains make beta-lactamase, rendering them resistant to amoxicillin. Penicillin nonsusceptible pneumococci, the main target of antibiotic therapy in the 1990s, has become a much less common isolate (10%- 25% of the total). These changes impact antibiotic selection for acute otitis media. Penicillin treatment of group A streptococcal tonsillopharyngitis does not meet the minimum United States Food and Drug Administration standards for first-line treatment, which is 85% or greater eradication at the end of therapy. Recent results with amoxicillin suggest its efficacy is also waning. Cephalosporins have the highest bacteriologic and clinical efficacy. This has implications for optimal antibiotic therapy.

Group A beta-hemolytic streptococcal pharyngitis in children

Group A beta-hemolytic streptococcus (GABHS) is the most common bacterial cause of acute pharyngitis in children. Because clinical findings can be nonspecific, even experienced physicians cannot reliably diagnose GABHS pharyngitis solely on the basis of clinical presentation. Suspected cases should be confirmed by a throat culture or a rapid antigen detection test before antibiotic therapy is initiated. Microbiologic testing is generally not necessary in patients with pharyngitis whose clinical and epidemiologic findings are not suggestive of GABHS. Clinical score systems have been developed to help physicians decide which patients should undergo diagnostic testing and to reduce the unnecessary use of antibiotics. Antibiotic therapy should be initiated as soon as the diagnosis is confirmed. Penicillin V remains the drug of choice. Alternative therapy, e.g., with cephalosporin or macrolide, is often sought because of penicillin allergy, noncompliance, and treatment failure.

Acute Streptococcal Tonsillopharyngitis: A Review of Clinical Efficacy and Bacteriological Eradication

This review evaluates studies published between January 1997 and August 2003 comparing clinical outcome and bacteriological eradication rates for patients with acute streptococcal tonsillopharyngitis treated with penicillin or other antimicrobial agents. Studies were identified using MEDLINE, and clinical outcome and bacteriological eradication at end of treatment and 2 weeks after end of treatment were ascertained. Any longer-term follow-up was also noted, along with treatment-related adverse events and compliance. Clinical efficacy rates between penicillin and comparator antibiotics were generally high and similar. Bacterial eradication rates were more variable and, 2 weeks after treatment, ranged from 64% to 93% for penicillin and 31% to 98% for comparators. Simpler dosing schedules and shorter therapy durations produced higher compliance rates. This review highlights the similarities and differences between treatment with penicillin and a wide range of comparator antibiotics. Therapy for acute group A streptococcal pharyngitis should combine excellent clinical efficacy, high bacteriological eradication rates, good tolerance and a simple, convenient dosing regimen.

The impact of dosing frequency on the efficacy of 10-day penicillin or amoxicillin therapy for streptococcal tonsillopharyngitis: A meta-analysis

OBJECTIVE

The recommended dosing frequency of oral penicillin for the treatment of acute streptococcal tonsillopharyngitis has long been 3 to 4 times daily. In 1994, treatment guidelines included twice-daily (BID) dosing for the first time, a recommendation that could significantly increase the ease of compliance. This meta-analysis was performed to determine whether overall cure rates differed between BID or once-daily (QD) versus more frequent dosing schedules in the treatment of streptococcal tonsillopharyngitis.

DATA SOURCES

Candidate studies for this meta-analysis included all clinical trials of therapy for streptococcal tonsillopharyngitis published through August 1998 and identified using Medline, Dissertation Abstracts, conference proceedings, and bibliographies of all retrieved articles.

STUDY SELECTION

A study was eligible for inclusion if it was a randomized clinical trial that compared the efficacies of different dosing frequencies of 10-day penicillin or amoxicillin in the treatment of streptococcal tonsillopharyngitis. Of the 30 articles initially identified, 6 studies met eligibility criteria.

OUTCOME MEASURE

The measure of interest was the difference in proportion cured between the BID or QD dosing group and the comparison group with more frequent dosing.

RESULTS

The results of this analysis suggest that BID dosing of 10-day penicillin is as efficacious as more frequent dosing regimens in the treatment of streptococcal tonsillopharyngitis. This result also holds true in a subgroup analysis confined to pediatric cases and does not vary with total daily dose of the regimen. QD dosing of penicillin is associated with a cure rate that is 12 percentage points lower than more frequent dosing (95% confidence interval: 3-21). In contrast, this decreased efficacy is not found with QD dosing of amoxicillin.

CONCLUSIONS

This meta-analysis supports current recommendations for BID dosing of penicillin in treating streptococcal tonsillopharyngitis. QD penicillin is associated with decreased efficacy and should not be used. Simplified regimens of amoxicillin of shorter duration or of less frequent dosing should be further investigated.