Streptococcal pharyngitis in children: a meta-analysis of clinical decision rules and their clinical variables

Abstract

ObjectiveTo identify the best clinical decision rules (CDRs) for diagnosing group A streptococcal (GAS) pharyngitis in children. A combination of symptoms could help clinicians exclude GAS infection in children with pharyngitis.DesignSystematic review and meta-analysis of original articles involving CDRs in children. The Pubmed, OVID, Institute for Scientific and Technical Information and Cochrane databases from 1975 to 2010 were screened for articles that derived or validated a CDR on a paediatric population: 171 references were identified.SettingAny reference including primary care for children with pharyngitis.Data extractionThe methodological quality of the articles selected was analysed according to published quality standards. A meta-analysis was performed to assess the statistical performance of the CDRs and their variables for the diagnosis of GAS pharyngitis.Primary outcome measureThe main criterion was a false-negative rate in the whole population not any worse than that of a rapid diagnostic test strategy for all patients (high sensitivity and low negative likelihood ratio).Results4 derived and 12 validated CDRs for this diagnosis in children. These articles involved 10 523 children (mean age, 7 years; mean prevalence of GAS pharyngitis, 34%). No single variable was sufficient for diagnosis. Among the CDRs, that of Joachim et al had a negative likelihood ratio of 0.3 (95% CI 0.2 to 0.5), resulting in a post-test probability of 13%, which leads to 3.6% false-negative rate among low-risk patients and 10.8% overall, equivalent to rapid diagnostic tests in some studies.ConclusionsThe rule of Joachim et al could be useful for clinicians who do not use rapid diagnostic tests and should allow avoiding antibiotic treatment for the 35% of children identified by the rule as not having GAS pharyngitis. Owing to its poor specificity, such CDR should be used to focus rapid diagnostic tests to children with high risk of GAS pharyngitis to reduce the antibiotic consumption.

Molecular and Clinical Diagnosis of Group A Streptococcal Pharyngitis in Children

“…It was apparent that, while some guidelines exist for clinicians in the ED to determine whether screening for GAS pharyngitis would be valuable in guiding further management, these are not always adhered to, resulting in a number of patients being included in the study whose positive test results likely represent carrier status. Despite the fact that there was no correlation between RADT, culture, or molecular assay results and clinical scores, a finding consistent with other studies (6,25), 16/20 patients with new positive results with the illumigene GAS assay had McIsaac scores of Ն2, and 7 patients with scores of 4 presented with clinical signs and symptoms of GAS pharyngitis. Of note, only patients for whom the clinical decision was made to obtain throat swab specimens were included in this study; therefore, we cannot fully assess the impact of asymptomatic carrier status by molecular methods.…”

“…The current IDSA guidance specifies that a throat culture should be performed for children with negative RADT results and treatment is indicated when the results of either test are positive. Clinical scoring systems, namely, Centor and McIsaac scores, integrate signs and symptoms to diagnose GAS pharyngitis (6,7). Additionally, the McIsaac scoring system considers children 3 to 14 years of age to be at higher risk (8,9).…”

Selective testing strategies for diagnosing group A streptococcal infection in children with pharyngitis: a systematic review and prospective multicentre external validation study

“…16 Clinical prediction rules for pharyngitis have not been sufficiently validated for clinical practice and have never been compared head-tohead in a single pediatric population from a highincome country. 18 The purpose of our study was to externally validate and directly compare the diagnostic accuracy of relevant rules-based selective testing strategies with original data from a French prospective multicentre cohort of children with pharyngitis. To optimize this validation study, we first conducted a systematic review of existing clinical prediction rules.…”

“…[15][16][17][18] These rules aim to identify patients at low risk in whom the disease can be managed without further testing and without antibiotic treatment, and patients at high risk who could receive empiric antibiotic treatment without testing. 16 Clinical prediction rules for pharyngitis have not been sufficiently validated for clinical practice and have never been compared head-tohead in a single pediatric population from a highincome country.…”

“…We assessed the quality of included studies using a combination of items from methodological standards for clinical prediction rules [19][20][21][22] and clinical prediction models, [24][25][26] (with the assessment of validation based on results from previous reviews). [15][16][17][18] One reviewer (JFC) performed the study selection, data extraction, and assessment of study quality and level of evidence, which were then checked by a second reviewer (MC). Discrepancies were discussed and resolved by consensus.…”