Accuracy and precision of the signs and symptoms of streptococcal pharyngitis in children: a systematic review

Appropriateness of Use of Streptococcal Pharyngitis Testing and Associated Antibiotic Prescribing in the Urgent Care Setting

The primary objective was to evaluate Group A streptococcal (GAS) tests performed with a Modified Centor Criteria (MCC) Score < 3 at Urgent Care Clinics (UCC). Secondary objectives included evaluating the MCC sensitivity and specificity, antibiotics prescribed with an MCC score < 3, and association between palatal petechiae and GAS pharyngitis infections. This was a retrospective review from July 1, 2018, to June 30, 2019, of Rapid Antigen Detection Tests (RADTs) on patients with ICD codes associated with pharyngitis. Fifteen hundred patient charts were reviewed. The majority of MCC scores were < 3 at 60.0% (878/1464). Sensitivity of GAS testing (RADT/culture) slightly increased for MCC scores ≥ 3 and was better than the specificity of those scores. In comparison, MCC scores < 3, showed better specificity compared to sensitivity. Over 50% of RADTs performed were inappropriate per clinical guidelines. MCC score < 3 had higher rates of negative test results.

Diagnostic performance of clinical prediction rules to detect group A beta-haemolytic streptococci in people with acute pharyngitis: a systematic review

OBJECTIVE

To assess and compare the diagnostic performance of Clinical Prediction Rules (CPRs) developed to detect group A Beta-haemolytic streptococci in people with acute pharyngitis (or sore throat).

STUDY DESIGN

A systematic review.

METHODS

We searched PubMed, Embase and Web of Science (inception-September 2022) for studies deriving and/or validating CPRs comprised of ≥2 predictors from an individual's history or physical examination. Two authors independently screened articles, extracted data and assessed risk of bias in included studies. A meta-analysis was not possible due to heterogeneity. Instead we compared the performance of CPRs when they were validated in the same study population (head-to-head comparisons). We used a modified grading of recommendations, assessment, development, and evaluations (GRADE) approach to assess certainty of the evidence.

RESULTS

We included 63 studies, all judged at high risk of bias. Of 24 derived CPRs, 7 were externally validated (in 46 external validations). Five validation studies provided data for head-to-head comparison of four pairs of CPRs. Very low certainty evidence favoured the Centor CPR over the McIsaac (2 studies) and FeverPain CPRs (1 study) and found the Centor CPR was equivalent to the Walsh CPR (1 study). The AbuReesh and Steinhoff 2005 CPRs had a similar poor discriminative ability (1 study). Within and between study comparisons suggested the performance of the Centor CPR may be better in adults (>18 years).

CONCLUSION

Very low certainty evidence suggests a better performance of the Centor CPR. When deciding about antibiotic prescribing for pharyngitis patients, involving patients in a shared decision making discussion about the likely benefits and harms, including antibiotic resistance, is recommended. Further research of higher rigour, which compares CPRs across multiple settings, is needed.

Influence of a guideline or an additional rapid strep test on antibiotic prescriptions for sore throat: the cluster randomized controlled trial of HALS (Hals und Antibiotika Leitlinien Strategien)

BACKGROUND

Pharyngitis due to Group A beta-hemolytic streptococci (GAS) is seen as the main indication for antibiotics for sore throat. In primary care settings prescription rates are much higher than the prevalence of GAS. Recommendations in international guidelines differ considerably. A German guideline suggested to consider antibiotics for patients with Centor or McIsaac scores ≥ 3, first choice being penicillin V for 7 days, and recommended analgesics for all. We investigated, if the implementation of this guideline lowers the antibiotic prescription rate, and if a rapid antigen detection strep-test (RADT) in patients with scores ≥ 3 lowers the rate further.

METHODS

HALS was an open pragmatic parallel group three-arm cluster-randomized controlled trial. Primary care practices in Northern Germany were randomized into three groups: Guideline (GL-group), modified guideline with a RADT for scores ≥ 3 (GL-RADT-group) or usual care (UC-group). All practices were visited and instructed by the study team (outreach visits) and supplied with material according to their group. The practices were asked to recruit 11 consecutive patients ≥ 2 years with an acute sore throat and being at least moderately impaired. A study throat swab for GAS was taken in every patient. The antibiotic prescription rate at the first consultation was the primary outcome.

RESULTS

From October 2010 to March 2012, 68 general practitioners in 61 practices recruited 520 patients, 516 could be analyzed for the primary endpoint. Antibiotic prescription rates did not differ between groups (p = 0.162) and were about three times higher than the GAS rate: GL-group 97/187 patients (52%; GAS = 16%), GL-RADT-group 74/172 (43%; GAS = 16%) and UC-group 68/157 (43%; GAS = 14%). In the GL-RADT-group 55% of patients had scores ≥ 3 compared to 35% in GL-group (p < 0.001). After adjustment, in the GL-RADT-group the OR was 0.23 for getting an antibiotic compared to the GL-group (p = 0.010), even though 35 of 90 patients with a negative Strep-test got an antibiotic in the GL-RADT-group. The prescription rates per practice covered the full range from 0 to 100% in all groups.

CONCLUSION

The scores proposed in the implemented guideline seem inappropriate to lower antibiotic prescriptions for sore throat, but better adherence of practitioners to negative RADTs should lead to fewer prescriptions.

TRIAL REGISTRATION

DRKS00013018, retrospectively registered 28.11.2017.

Diagnosis of group A streptococcal pharyngitis in the paediatric emergency department using a fluorescence-based RADT: predicted impact on antibiotic prescription

Introduction. Using rapid antigen diagnostic tests (RADTs) in clinical practice has shown excellent specificity but often has diminished sensitivity.Gap Statement. Local data for evaluating the diagnostic performance of a new fluorescence-based RADT and its influence on the antibiotic prescription rate are not available.Aim. To evaluate the accuracy of fluorescent immunoassay (FIA)-RADTs for diagnosing group A streptococcal (GAS) pharyngitis among children and its estimated effect as a point of care test (POCT) on the antibiotic prescription rate at the paediatric emergency department.Methodology. A prospective study was conducted, comprising children 3 to 14 years old presenting with pharyngitis. Throat swab culture and FIA-RADTs were performed on all samples. Conventional PCR was performed on the discordant samples.Results. A total of 246 children were included in this study. The sensitivity, specificity, and positive and negative predictive values of the FIA-RADT, based on culture results and PCR detection combined, were 95.6, 96.8, 94.6 and 97.4 %, respectively. Antibiotics have been prescribed to 162 (65.9 %) children; however, if FIA-RADTs had been added in the clinical practice as a POCT, only 92 (37.4 %) children would have received antibiotics in total. Additionally, implementation of FIA-RADTs would significantly reduce the antibiotic prescription rate from 48.8 and 60.6 % to 9.5 and 31.9 % among patients with clinical scores of 2 and 3, respectively.Conclusion. The new FIA-RADT is simple, prompt and reliable. It is helpful in clinical settings and may be used to reduce antibiotic overprescription, especially for children who have a low risk for GAS pharyngitis, according to the clinical score.

Nasopharyngeal rapid diagnostic testing to reduce unnecessary antibiotic use and individualize management of acute otitis media

Background:

Acute otitis media (AOM) is the most common indication for antibiotics in children. The associated organism can influence the likelihood of antibiotic benefit and optimal treatment. Nasopharyngeal polymerase chain reaction can effectively exclude the presence of organisms in middle-ear fluid. We explored the potential cost-effectiveness and reduction in antibiotics with nasopharyngeal rapid diagnostic testing (RDT) to direct AOM management.

Methods:

We developed 2 algorithms for AOM management based on nasopharyngeal bacterial otopathogens. The algorithms provide recommendations on prescribing strategy (ie, immediate, delayed, or observation) and antimicrobial agent. The primary outcome was the incremental cost-effectiveness ratio (ICER) expressed as cost per quality-adjusted life day (QALD) gained. We used a decision-analytic model to evaluate the cost-effectiveness of the RDT algorithms compared to usual care from a societal perspective and the potential reduction in annual antibiotics used.

Results:

An RDT algorithm that used immediate prescribing, delayed prescribing, and observation based on pathogen (RDT-DP) had an ICER of $1,336.15 per QALD compared with usual care. At an RDT cost of $278.56, the ICER for RDT-DP exceeded the willingness to pay threshold; however, if the RDT cost was <$212.10, the ICER was below the threshold. The use of RDT was estimated to reduced annual antibiotic use, including broad-spectrum antimicrobial use, by 55.7% ($4.7 million for RDT vs $10.5 million for usual care).

Conclusion:

The use of a nasopharyngeal RDT for AOM could be cost-effective and substantially reduce unnecessary antibiotic use. These iterative algorithms could be modified to guide management of AOM as pathogen epidemiology and resistance evolve.

Use of Host Response to Refine the Diagnosis of Group A Streptococcal Pharyngitis

BACKGROUND

Current diagnostic tests for pharyngitis do not distinguish between symptomatic group A Streptococcus (GAS) infection and asymptomatic colonization, resulting in over-diagnosis and unnecessary use of antibiotics. We assessed whether measures of host response could make this distinction.

METHODS

We enrolled 18 children with pharyngitis having Centor scores of 4 or 5 and 21 controls without pharyngitis or other acute infections. Both groups had throat cultures, molecular tests for GAS and respiratory viruses and IgM serology for Epstein-Barr virus. Host response was evaluated with white blood cell count (WBC), C-reactive protein (CRP), procalcitonin (PCT), and sequencing of RNA from peripheral blood leukocytes.

RESULTS

Of 18 cases, 11 had GAS pharyngitis, 3 had adenovirus pharyngitis and 4 had other pharyngitis. Among asymptomatic controls, 5 were positive for GAS. WBC, CRP, and PCT were higher in subjects with pharyngitis compared to asymptomatic controls including those with GAS. Transcriptional profiles from children with symptomatic GAS were clearly distinct from those of children in all other groups. The levels of two genes, CD177 and TLR5 each individually accurately distinguished between symptomatic and asymptomatic GAS. Optimal diagnostic sensitivity and specificity were achieved by the combination of CRP and PCT, and by each of the two gene markers.

CONCLUSION

In this exploratory study, we showed that traditional measures of inflammation and markers of host gene expression distinguish between symptomatic and asymptomatic GAS. These results point to future rapid molecular approaches for improving the diagnosis of GAS pharyngitis, that may help reduce unnecessary antibiotic use.

Recent Advances in the Rheumatic Fever and Rheumatic Heart Disease Continuum

Nearly a century after rheumatic fever (RF) and rheumatic heart disease (RHD) was eradicated from the developed world, the disease remains endemic in many low- and middle-income countries (LMICs), with grim health and socioeconomic impacts. The neglect of RHD which persisted for a semi-centennial was further driven by competing infectious diseases, particularly the human immunodeficiency virus (HIV) pandemic. However, over the last two-decades, slowly at first but with building momentum, there has been a resurgence of interest in RF/RHD. In this narrative review, we present the advances that have been made in the RF/RHD continuum over the past two decades since the re-awakening of interest, with a more concise focus on the last decade’s achievements. Such primary advances include understanding the genetic predisposition to RHD, group A Streptococcus (GAS) vaccine development, and improved diagnostic strategies for GAS pharyngitis. Echocardiographic screening for RHD has been a major advance which has unearthed the prevailing high burden of RHD and the recent demonstration of benefit of secondary antibiotic prophylaxis on halting progression of latent RHD is a major step forward. Multiple befitting advances in tertiary management of RHD have also been realized. Finally, we summarize the research gaps and provide illumination on profitable future directions towards global eradication of RHD.

The aetiology of pharyngotonsillitis in primary health care: a prospective observational study

Background

Few studies on pharyngotonsillitis have examined the clinical presentation of different aetiologies where pathogens have been detected using molecular methods. We aimed to assess how well clinical signs and symptoms can predict (1) the presence or absence of a broad range of viruses and bacteria, and (2) reconsultations for a sore throat or a complication.

Methods

In this descriptive observational prospective study in primary health care 220 patients aged 15–45 with suspected pharyngotonsillitis were sampled from nose, throat and blood and screened for 20 bacteria and viruses using polymerase chain reaction (PCR), culture and serology. Odds ratios (OR) and predictive values with 95% confidence intervals (CI) were used to show association between microbiological findings and clinical signs and symptoms. Patients were followed up after 3 months by reviewing electronic medical records.

Results

Both cough and coryza were more common in patients with only viruses (67%) than in patients with only bacteria (21%) (p < 0.001), whereas tonsillar coating was more common in patients with only bacteria (53%) than in patients with only viruses (29%) (p = 0.006). Tonsillar coating (adjusted OR 6.0; 95% CI 2.5–14) and a lack of cough (adjusted OR 3.5; 95% CI 1.5–8.0) were significantly associated with Streptococcus pyogenes (group A streptococci; GAS) and with any bacterial finding. A Centor score of 3–4 had a positive predictive value of 49% (95% CI 42–57) for GAS and 66% (95% CI 57–74) for any bacterial findings. The use of rapid antigen detection test for GAS increased the positive predictive value for this group to 93%.

Conclusions

Signs and symptoms, both single and combined, were insufficient to rule in GAS or other pathogens. However, both cough and coryza were useful to rule out GAS. The results support the clinical approach of restricting rapid antigen detection testing to patients with 3–4 Centor criteria. The low carriage rate of bacteria among asymptomatic controls implied that most detections in patients represented a true infection.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06665-9.

The treatment of streptococcal tonsillitis/pharyngitis in young children

Pharyngitis is common in children, accounting for nearly 12 million visits annually in the United States. Streptococcus pyogenes or group A streptococcus (GAS) is the most common bacterial cause of pharyngitis for which antibiotics are indicated. Antibiotic treatment of streptococcal pharyngitis virtually eliminates the presence of bacteria from the pharynx and thus removes the risk of subsequent rheumatic fever. GAS is spread from person to person via respiratory droplets with a short incubation period of 2∼5 days. GAS pharyngitis peaks in the late winter and early spring months when children are predominately indoors for school and sports. Colonization is also higher in winter months, and while up to 20% of school age children are colonized with GAS in their throat during this time, colonization has not been shown to contribute to the spread of disease. In low- and middle-income countries and other situations in which crowding is common (e.g., schools), outbreaks of pharyngitis are common. GAS pharyngitis can occur at all ages and it is most common in school-aged children with a peak at 7∼8 years of age. Pharyngitis caused by GAS is rare in children <3 years of age and becomes much less common in late adolescence through adulthood.

Presence of microorganisms in children with pharyngotonsillitis and healthy controls: a prospective study in primary healthcare

Purpose

Most studies on paediatric pharyngotonsillitis focus on group A streptococci. This study, however, analyses a broad spectrum of bacteria and viruses related to paediatric pharyngotonsillitis and evaluates their associated clinical symptoms and courses.

Methods

This observational prospective study in primary healthcare includes 77 children aged < 15 with a sore throat and 34 asymptomatic children, all of whom were sampled from the tonsils with an E-swab^® for analysis with culture and PCR for 14 bacteria and 15 viruses. Patients were evaluated clinically, and their symptoms recorded in diaries for 10 days. Participants were followed up for 3 months by reviewing medical records.

Results

A pathogen was detected in 86% of patients and in 71% of controls (P = 0.06). Bacteria were found in 69% of patients and 59% of controls (P = 0.3), and viruses in 36% and 26%, respectively (P = 0.3). Group A streptococci was the most common finding, with a prevalence of 49% and 32%, respectively (P = 0.1). Clinical signs were not useful for distinguishing pathogens. None of the controls and 16% of the patients reconsulted for a sore throat within 3 months.

Conclusion

Bacteria were more common than viruses in both study groups. The high rate of pathogens in asymptomatic children interferes with diagnoses based on aetiology.

Supplementary Information

The online version contains supplementary material available at 10.1007/s15010-021-01595-9.

Rheumatic Fever and Rheumatic Heart Disease in the United States

During the 1920s, acute rheumatic fever (ARF) was the leading cause of mortality in children in the United States. By the 1980s, many felt ARF had all but disappeared from the US. However, although ARF and rheumatic heart disease (RHD) rates remain low in the US today, disease burden is unequal and tracks along other disparities of cardiovascular health. It is estimated that 1% to 3% of patients with untreated group A streptococcus (GAS) infection, most typically GAS pharyngitis, will develop ARF, and of these, up to 60% of cases will result in chronic RHD. This article reviews the epidemiology, pathogenesis, diagnosis, and management of ARF/RHD to increase awareness of ARF/RHD for clinicians based in the US. [Pediatr Ann. 2021;50(3):e98-e104.].

Retrospective study of group A Streptococcus oropharyngeal infection diagnosis using a rapid antigenic detection test in a paediatric population from the central region of Portugal

Group A Streptococcus (GAS) is one of the most important agents of oropharyngeal infection. To avoid unnecessary antibiotic prescription, it is recommended the confirmation of GAS infection in pharyngeal swabs using culture or rapid antigen detection test (RADT). This study aimed to retrospectively analyse the incidence of GAS oropharyngeal infection, detected by RADT, in a paediatric population in the Centre of Portugal. Data was collected from the database of the Paediatric Hospital Emergency Department (ED) regarding patients admitted with symptoms suggesting acute pharyngitis, from January 2013 to December 2018, in a total of 18,304 cases. Among these, 130 clinical files were searched for symptoms, complications and additional visits to the ED. The results showed an average GAS infection prevalence of 33%, with seasonal variation. In preschool children, especially in patients less than 3 years old, where the guidelines do not routinely encourage RADT, GAS tonsillitis assumed an unexpected importance, with 731 positive tests in a total of 3128 cases. Scarlatiniform rash and oral cavity petechiae had significant correlation with streptococcal aetiology (p < 0.05). The statistical analysis also showed that different signs and symptoms assume different weights depending on the age group of the patient. The main conclusion is that the incidence of GAS infection in the studied population is higher than generally described in preschool children, suggesting the need for a more cautious approach to children under 3 years presenting acute pharyngitis, and that RADT in this age group would contribute to a decrease in the number of unnoticed cases.

Diagnostic Methods, Clinical Guidelines, and Antibiotic Treatment for Group A Streptococcal Pharyngitis: A Narrative Review

The most common bacterial cause of pharyngitis is infection by Group A β-hemolytic streptococcus (GABHS), commonly known as strep throat. 5-15% of adults and 15-35% of children in the United States with pharyngitis have a GABHS infection. The symptoms of GABHS overlap with non-GABHS and viral causes of acute pharyngitis, complicating the problem of diagnosis. A careful physical examination and patient history is the starting point for diagnosing GABHS. After a physical examination and patient history is completed, five types of diagnostic methods can be used to ascertain the presence of a GABHS infection: clinical scoring systems, rapid antigen detection tests, throat culture, nucleic acid amplification tests, and machine learning and artificial intelligence. Clinical guidelines developed by professional associations can help medical professionals choose among available techniques to diagnose strep throat. However, guidelines for diagnosing GABHS created by the American and European professional associations vary significantly, and there is substantial evidence that most physicians do not follow any published guidelines. Treatment for GABHS using analgesics, antipyretics, and antibiotics seeks to provide symptom relief, shorten the duration of illness, prevent nonsuppurative and suppurative complications, and decrease the risk of contagion, while minimizing the unnecessary use of antibiotics. There is broad agreement that antibiotics with narrow spectrums of activity are appropriate for treating strep throat. But whether and when patients should be treated with antibiotics for GABHS remains a controversial question. There is no clearly superior management strategy for strep throat, as significant controversy exists regarding the best methods to diagnose GABHS and under what conditions antibiotics should be prescribed.

Emergency Department Prescribing Patterns for Pharyngitis in Children

Pharyngitis is commonly diagnosed in the emergency department (ED) and accounts for substantial antibiotic burden in pediatrics. This study describes ED patterns of group A streptococcal (GAS) pharyngitis diagnosis and antibiotic prescribing patterns. This was a secondary data analysis of the National Hospital Ambulatory Medical Care Survey. Diagnosis and antibiotic treatment for GAS and non-GAS (viral) pharyngitis were reported in all ages and specifically examined in children <3 years of age from 2010 to 2015. GAS pharyngitis was diagnosed in 29% of visits for children with pharyngitis; however, 60% of patients with any pharyngitis received antibiotics. Twenty percent of children <3 years were diagnosed with GAS pharyngitis, yet over half were given antibiotics. Broad-spectrum antibiotics were commonly prescribed. Antibiotic treatment of pharyngitis, including broad-spectrum antibiotics, remains high when compared with the known prevalence of GAS pharyngitis. Diagnosis and treatment of GAS pharyngitis in patients <3 years persists despite recommendations against testing.

Efficacy and safety of rapid tests to guide antibiotic prescriptions for sore throat

BACKGROUND

Sore throat is a common condition caused by viruses or bacteria, and is a leading cause of antibiotic prescription in primary care. The most common bacterial species is group A streptococcus ('strep throat'). Between 50% to 70% of pharyngitis cases are treated with antibiotics, despite the majority of cases being viral in origin. One strategy to reduce antibiotics is to use rapid tests for group A streptococcus to guide antibiotic prescriptions. Rapid tests can be used alone or in combination with a clinical scoring system.

OBJECTIVES

To assess the efficacy and safety of strategies based on rapid tests to guide antibiotic prescriptions for sore throat in primary care settings.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, Web of Science, and LILACS, as well as the trial registries ClinicalTrials.gov and the WHO ICTRP on 5 June 2019.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing rapid tests with management based on clinical grounds to guide the prescription of antibiotics for people with a sore throat in ambulatory care settings. We included trials that randomised individuals, as well as cluster-RCTs in which individual practitioners (or practices) or emergency departments were randomised.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data on the primary outcomes (number of participants provided with an antibiotic prescription; number of participants with an antibiotic dispensed) and secondary outcomes (duration of sore throat symptoms; duration of other symptoms; quality of life measures; number of participants with a complication attributed to the index infection; number of participants in need of re-consultation by the end of follow-up; number of participants in need of hospital admission by the end of follow-up; number of satisfied participants; number of participants with an adverse event attributed to the rapid test). We assessed the risk of bias of all included trials and used GRADE to assess the certainty of the evidence. We performed meta-analyses and sensitivity analyses when feasible.

MAIN RESULTS

We included five trials (2891 children and adult participants in total; 2545 participants after adjusting for clustering). Management in the intervention group was as follows: in three trials rapid tests were used in combination with a clinical scoring system; in one trial, some physicians were asked to use rapid tests alone, while others were asked to use rapid tests in combination with a clinical scoring system; in one trial, rapid tests were used alone. Based on data from five trials (2545 participants), a large reduction in prescribed antibiotics was found in the rapid test group (481/1197) versus management based on clinical grounds (865/1348), for a summary risk difference (RD) of -25%, 95% confidence interval (CI) -31% to -18%; I² = 62%; moderate-certainty evidence. Estimates of effect on antibiotic prescription rates were stable in various sensitivity analyses. Based on data from two trials (900 people) originating from the same overarching study, the evidence suggests that rapid tests may not reduce dispensed antibiotic treatments: rapid test group (156/445) versus management based on clinical grounds (197/455); summary RD -7%, 95% CI -17% to 2%; I² = 53%; low-certainty evidence. Four trials (2075 participants) reported data on the number of participants with a complication attributed to the index infection; the summary odds ratio (OR) was 0.85, 95% CI 0.03 to 26.65; P = 0.93; I² = 62%; very low-certainty evidence, which means that people in the rapid testing group were less likely to develop complications of the index infection, but the evidence is very uncertain. Two trials (1161 participants) reported on the number of participants in need of re-consultation by the end of follow-up; the summary OR was 1.12, 95% CI 0.57 to 2.21; P = 0.74; I² = 59%; low-certainty evidence, which means that participants in the rapid testing group were more likely to be in need of re-consultation by the end of the study follow-up, but the evidence is uncertain. Lack of data impeded assessment of other secondary outcomes (including safety outcomes) and of sources of heterogeneity.  AUTHORS' CONCLUSIONS: Rapid testing to guide antibiotic treatment for sore throat in primary care probably reduces antibiotic prescription rates by 25% (absolute risk difference), but may have little or no impact on antibiotic dispensing. More studies are needed to assess the efficacy and safety of rapid test-guided antibiotic prescribing, notably to evaluate patient-centred outcomes and variability across subgroups (e.g. adults versus children).

Identifying Patients at Lowest Risk for Streptococcal Pharyngitis: A National Validation Study

OBJECTIVES

To determine the prevalence of features of viral illness in a national sample of visits involving children tested for group A Streptococcus pharyngitis. Additionally, we sought to derive a decision rule to identify patients with features of viral illness who were at low risk of having group A Streptococcus and for whom laboratory testing might be avoided.

STUDY DESIGN

Retrospective validation study using data from electronic health records of patients 3-21 years old evaluated for sore throat in a national network of retail health clinics (n = 67 127). We determined the prevalence of features of viral illness in patients tested for group A Streptococcus and developed a decision tree algorithm to identify patients with features of viral illness at low risk (<15%) of having group A Streptococcus.

RESULTS

Overall, 54% of patients had features of viral illness. Among patients with features of viral illness, those without tonsillar exudates who were 11 years or older and either lacked cervical adenopathy or had cervical adenopathy and lacked fever were identified as at low risk for group A Streptococcus according to the decision rule. This group comprised 34% of patients with features of viral illness, or 19% of all patients tested for group A Streptococcus infection.

CONCLUSIONS

Our findings provide an objective way to identify patients with features of viral illness who are at low risk of having group A Streptococcus. Improved identification such patients at low risk of group A Streptococcus could improve appropriate testing and antibiotic prescribing for pharyngitis.

Alterations in the Nervous System and Gut Microbiota after β-Hemolytic Streptococcus Group A Infection-Characteristics and Diagnostic Criteria of PANDAS Recognition

The objective of this paper is to review and summarize conclusions from the available literature regarding Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS). The authors have independently reviewed articles from 1977 onwards, primarily focusing on the etiopathology, symptoms, differentiation between similar psychiatric conditions, immunological reactions, alterations in the nervous system and gut microbiota, genetics, and the available treatment for PANDAS. Recent research indicates that PANDAS patients show noticeable alterations within the structures of the central nervous system, including caudate, putamen, globus pallidus, and striatum, as well as bilateral and lentiform nuclei. Likewise, the presence of autoantibodies that interact with basal ganglia was observed in PANDAS patients. Several studies also suggest a relationship between the presence of obsessive-compulsive disorders like PANDAS and alterations to the gut microbiota. Further, genetic predispositions-including variations in the MBL gene and TNF-α-seem to be relevant regarding PANDAS syndrome. Even though the literature is still scarce, the authors have attempted to provide a thorough insight into the PANDAS syndrome, bearing in mind the diagnostic difficulties of this condition.

Caracterización del uso inapropiado de antibióticos en faringoamigdalitis según los criterios de McIsaac

Objetivo: Describir el uso irracional de antibióticos en base a criterios de McIsaac (criterios de Centor modificados por McIsaac), en una unidad de salud de primer nivel de atención. Métodos: Se realizó un estudio descriptivo transversal con los registros de pacientes de 3 a 19 años atendidos en el servicio de emergencia (246), con los diagnósticos de faringitis aguda, amigdalitis aguda, e infecciones respiratorias superiores agudas de múltiples sitios y sin especificar. Se estableció como prescripción inadecuada si el facultativo indicó antibióticos con un puntaje menor o igual a 1 sobre 5 puntos o si no prescribió antibióticos con puntaje mayor o 4 sobre 5 puntos. Resultados: Se estimó 24,29% de uso inadecuado de antibióticos de los registros de emergencia. Se prescribió antibióticos en 160 pacientes, de los cuales se encontró que, amoxicilina fue el más utilizado (61,87%); seguido de benzilpenicilina benzatina (28,12%) y en tercer lugar macrólidos (8,12%). Conclusión: En la unidad de primer nivel analizada se encontró que el uso inadecuado de antibióticos es superior a la prevalecía estimada de faringoamigdalitis estreptocócica para el grupo de edad estudiado. Por esto, es imperativo que se tomen las medidas necesarias a nivel institucional y comunitario para lograr su reducción y evitar las complicaciones que se derivan de esta. 

Diagnostic accuracy of QuickVue® Dipstick Strep A test and its effect on antibiotic prescribing in children in the United Arab Emirates

Background

Unnecessary antibiotic prescription to patients with upper respiratory tract infections (URTIs) has led to the increase in antibiotics resistant bacteria rates. In this study, we evaluated the diagnostic accuracy of QuickVue® Dipstick Strep A test (QV-SAT) in children presenting with acute pharyngotonsillitis and its effect on antibiotic prescribing.

Methods

A single-gated diagnostic accuracy study of children with fever, runny nose, and tonsillitis presenting to a paediatric clinic between March 2016 and September 2018. Paired throat swabs for QV-SAT and culture were collected. None of the children received antibiotics prior to sample collection. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the test were calculated.

Results

Two hundred four children were included in this study. 111 (54.4%) were boys and 146 (71.6%) were under the age of 5 years. QV-SAT was positive in 44 (21.6%) and throat culture was positive for Group A β- haemolytic Streptococcus (GAS) in 42 (20.6%) of the children. The results of QV-SAT were highly consistent with culture results: only 2 (0.9%) children with negative results had a positive throat culture. The sensitivity of the QV-SAT in the identification of GAS infection was 100% (95% CI 91.6%, 100%) and the NPV was 100% (95% CI 99.9%, 100%). Only 42 children ( 20.6%) were given antibiotics, while 162 (79.4%) were not.

Conclusion

The QV-SAT is a quick and reliable test that can help dramatically reduce antibiotic prescriptions to children presenting with fever and acute pharyngotonsillitis.

Acute Otitis Media and Group A Streptococcal Pharyngitis: A Review for the General Pediatric Practitioner

For pediatric practitioners, acute otitis media (AOM) and group A streptococcal pharyngitis are two of the most common infections seen in ambulatory practices. The purpose of this article is to review these conditions with the focus of highlighting evidence-based guidelines. AOM in children is a visual diagnosis and not one that can be made on history alone. The American Academy of Pediatrics (AAP) guidelines have clear criteria to aid clinicians in how to diagnose AOM. The pneumatic otoscope is the standard tool used to diagnose otitis media, and the AAP guidelines stress developing proficiency in distinguishing a normal tympanic membrane from otitis media with effusion or AOM. There are several components to appropriate management (treatment) of AOM including analgesia, education, antibiotics, and the option (for some) for observation. Group A streptococcal pharyngitis is the most common bacterial cause of sore throat in children but still only accounts for a minority of cases. History and physical examination help determine who should be tested. Testing is required to determine who to treat. Up to 15% of children in the United States are carriers, so indiscriminate testing can lead to inappropriate antibiotic use. If a patient's test is positive, treatment is recommended and penicillin or amoxicillin are appropriate for most cases. [Pediatr Ann. 2019;48(9):e343-e348.].

Performance evaluation of three rapid antigen tests for the diagnosis of group A Streptococci

OBJECTIVE

To compare the diagnostic performance of three rapid antigen detection tests (RADTs) for group A Streptococcus (GAS).

DESIGN

A hospital-based, cross-sectional, retrospective study.

SETTING

A comparative study of rapid diagnostic tests for GAS using clinical specimens in a single institute.

PARTICIPANTS

225 children in the outpatient clinics ofKorea University Guro Hospitalwith suspicious symptoms were subjected to throat swab sampling. A dual-swab applicator was used. Samples were stored at below -70°C in a 10 mL transport tube containing 1 mL liquid Stuart's transport medium.

OUTCOME MEASURES

All tests were performed in the laboratory by trained clinical laboratory scientists. Sensitivity, specificity, accuracy and kappa index of three RADTs were compared with the reference PCR test and culture results.

RESULTS

Of the 225 patients suspected of having GAS, 67 and 90 were positive for GAS in the culture and PCR tests, respectively. Compared with the reference culture, the sensitivity for GAS was 92.5% (CI 83.4 to 97.5), 71.6% (CI 59.3 to 81.9) and 74.63% (CI 62.5 to 84.4) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively, and the specificity was 97.0% (CI 93.1 to 99.0), 94.6% (CI 90.1 to 97.5) and 92.9% (CI 87.8 to 96.2) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively. Compared with the reference GAS real-time PCR, the sensitivity was 73.3% (CI 62.9 to 82.1), 63.3% (CI 52.5 to 73.2) and 67.8% (CI 57.1 to 77.2) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively, and the specificity was 99.3% (CI 95.9 to 99.9), 100.0% (CI 97.3 to 100.0) and 99.3% (CI 95.9 to 99.9) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively.

CONCLUSIONS

The careUS Strep A Plus is a useful test that showed highly comparable results with those of the culture test and superior performances among the three RADTs. The use of RADTs should be encouraged to provide acceptable and fast results using simple equipment.

Clinical gestalt to diagnose pneumonia, sinusitis, and pharyngitis: a meta-analysis

BACKGROUND

The overall clinical impression ('clinical gestalt') is widely used for diagnosis but its accuracy has not been systematically studied.

AIM

To determine the accuracy of clinical gestalt for the diagnosis of community-acquired pneumonia (CAP), acute rhinosinusitis (ARS), acute bacterial rhinosinusitis (ABRS), and streptococcal pharyngitis, and to contrast it with the accuracy of clinical decision rules (CDRs).

DESIGN AND SETTING

Systematic review and meta-analysis of outpatient diagnostic accuracy studies in ambulatory care.

METHOD

PubMed and Google were searched for studies in outpatients that reported sufficient data to calculate accuracy of the overall clinical impression and that used the same reference standard. Study quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2), and measures of accuracy calculated using bivariate meta-analysis.

RESULTS

The authors identified 16 studies that met the inclusion criteria. The summary estimates for the positive (LR+) and negative likelihood ratios (LR-) were LR+ 7.7, 95% confidence interval (CI) = 4.8 to 11.5, and LR- 0.54, 95% CI = 0.42 to 0.65 for CAP in adults, LR+ 2.7, 95% CI = 1.1 to 4.3 and LR- 0.63, 95% CI = 0.20 to 0.98 for CAP in children, LR+ 3.0, 95% CI = 2.1 to 4.4 and LR- 0.37, 95% CI = 0.29 to 0.46 for ARS in adults, LR+ 3.9, 95% CI = 2.4 to 5.9 and LR- 0.33, 95% CI = 0.20 to 0.50 for ABRS in adults, and LR+ 2.1, 95% CI = 1.6 to 2.8 and LR- 0.47, 95% CI = 0.36 to 0.60 for streptococcal pharyngitis in adults and children. The diagnostic odds ratios were highest for CAP in adults (14.2, 95% CI = 9.0 to 21.0), ARS in adults (8.3, 95% CI = 4.9 to 13.1), and ABRS in adults (13.0, 95% CI = 5.0 to 27.0), as were the C-statistics (0.80, 0.77, and 0.84 respectively).

CONCLUSION

The accuracy of the overall clinical impression compares favourably with the accuracy of CDRs. Studies of diagnostic accuracy should routinely include the overall clinical impression in addition to individual signs and symptoms, and research is needed to optimise its teaching.

Association Between Rapid Antigen Testing and Antibiotic Use and Accuracy of Peripheral Blood Parameters in Detecting Group A Streptococcus in Children With Tonsillopharyngitis

Objectives: To investigate the effect of rapid antigen testing (RAT) on the practice of antibiotic prescription as well as the accuracy of peripheral blood neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) values in detecting group A beta-hemolytic Streptococcus (GABHS) in children with tonsillopharyngitis. Methods: In a multicenter study performed in Turkey, we retrospectively analyzed data from 668 consecutive pediatric patients under 17 years of age, who presented with signs and symptoms of tonsillopharyngitis and underwent RAT. The rates of positive and negative RAT results were determined and patients' antibiotic prescriptions were examined in relation to RAT results. In addition, the accuracy of peripheral blood NLR and CRP values was examined for 212 patients whose laboratory data were available, with RAT as the reference standard. Results: Positive RAT results were observed in 190 of 668 (28.4%) patients. Antibiotics were prescribed to all 190 patients with positive RAT results and to 8 of 478 patients with negative RAT results. Overall, the rate of antibiotic prescription was 29.6%. Patients with positive and negative RAT results did not differ significantly with regard to NLR and CRP values. In ROC analysis, the area under the ROC curve (AUC) of NLR and CRP were 0.54 (95% confidence interval [CI] 0.45-0.64), and 0.55 (95% CI 0.45-0.65), respectively. Conclusion: RAT results proved highly associated with antibiotic prescribing, suggesting that RATs could be of great value in preventing unnecessary antibiotic use. Our findings also suggest that NLR and CRP are poorly accurate to identify GABHS in children with tonsillopharyngitis.

Challenges in identifying antibiotic resistance targets for point-of-care diagnostics in general practice

General practitioners stand at the front line of healthcare provision and have a pivotal role in the fight against increasing antibiotic resistance. In this respect, targeted antibiotic prescribing by general practitioners would help reduce the unnecessary use of antibiotics, leading to reduced treatment failures, fewer side-effects for patients and a reduction in the (global) spread of antibiotic resistances. Current 'gold standard' antibiotic resistance detection strategies tend to be slow, taking up to 48 h to obtain a result, although the implementation of point-of-care testing by general practitioners could help achieve the goal of targeted antibiotic prescribing practices. However, deciding on which antibiotic resistances to include in a point-of-care diagnostic is not a trivial task, as outlined in this publication.

Community pharmacist-directed point-of-care group A Streptococcus testing: Evaluation of a Canadian program

OBJECTIVE

Streptococcus pyogenes is an aerobic, gram-positive bacterium responsible for a wide variety of infections including common pharyngitis. Novel rapid antigen detection tests allow for diagnosis of group A Streptococcus (GAS) at the point of care. The objective of the study is to evaluate the effects and feasibility of community pharmacist-directed GAS testing.

SETTING

A retrospective analysis of aggregate billing data was conducted using descriptive statistics to evaluate the acceptance and feasibility of a community pharmacist-directed Streptococcus testing program at Shoppers Drug Mart pharmacies in the Canadian provinces of British Columbia, Alberta, and Nova Scotia.

PRACTICE DESCRIPTION

Pharmacists trained in sample collection offered the screening to patients with symptoms suggestive of Streptococcus species infection from November 28, 2015, to May 31, 2016. Throat swabs were collected and analyzed using the BD Veritor system for rapid detection of GAS.

PRACTICE INNOVATION

Pharmacist-directed point-of-care group A Streptococcus testing and management.

EVALUATION

Proportion of GAS-positive cases that resulted in the same day initiation of antibiotic therapy by pharmacists were collected. Patient satisfaction with the service was also evaluated.

RESULTS

Seven thousand and fifty patients were tested across 204 participating locations. The average age was 27.3 years, with children (age 5-14 years) representing 30.7% of the population; 25.5% of patients tested positive for GAS infection. Of the patients with positive results, antibiotic therapy was initiated within the same day in 68.7% of cases. In Alberta, where pharmacists have advanced prescribing authority, same-day initiation of therapy was 73.8% compared with a rate of 40.5% (P < 0.05) in the other jurisdictions.

CONCLUSION

These results highlight both the public readiness to access point-of-care services in community pharmacies and the ability of pharmacists to expedite management of patients with GAS. Pharmacy-based Streptococcus testing can facilitate prompt and appropriate access to antibiotic therapy, as was demonstrated in regions with advanced prescribing authority. Communication of recommendations to the physician remains a barrier.

Streptococcal group A, C and G pharyngitis in school children: a prospective cohort study in Southern India

Diagnosing streptococcal pharyngitis in children on the basis of clinical appearance and throat culture is complicated by high colonisation rates and by the ability of other pathogens to cause clinically similar disease. To characterise the epidemiology of Lancefield Group A, C and G β-haemolytic streptococcus (GAS, GCS and GGS, respectively) in children, we conducted a 2-year prospective study of 307 school children between 7 and 11 years old. GGS and GAS were commonly identified organisms both for silent streptococcal colonisation and symptomatic sore throat, while GCS was uncommonly found. Streptococcal culture positivity at the time of clinical pharyngitis was estimated to reflect true streptococcal pharyngitis in only 26% of instances, with the frequency varying from 54% for children rarely colonised to 1% for children frequently colonised. Numerous GAS emm types were identified, including several types previously associated with severe pharyngitis (e.g. emm types 1, 3 and 28). No severe complications were seen in any child. These data suggest that the clinical diagnosis of streptococcal pharyngitis is likely to remain difficult and that treatment decisions will remain clouded by uncertainty. There remains a need for organism-specific rapid point-of-care streptococcal diagnostic tests and tests that can distinguish between streptococcal colonisation and disease.

Clinical features predicting group A streptococcal pharyngitis in a Japanese paediatric primary emergency medical centre

Objectives

To identify clinical features that predict Group A streptococcal (GAS) pharyngitis in a Japanese paediatric primary emergency medical centre.

Methods

The prevalence of GAS pharyngitis according to age and body temperature (BT) was calculated among 3098 paediatric patients with pharyngitis. The numbers of GAS-positive and -negative patients for each clinical parameter, and each point increase in the McIsaac score were compared and likelihood ratios (LRs) were calculated.

Results

The prevalence of GAS pharyngitis was extremely low in patients aged < 1 (1.2%) and 1 year (3.9%). The GAS-positive rate was significantly higher in patients with a BT < 38.0°C compared with ≥ 38.0°C (30.0% vs. 19.8%). A BT ≥ 38.0°C was not a predictive finding for GAS pharyngitis (positive LR: 0.82). Rash was the most useful individual predictor, and a McIsaac score of 4 or 5 increased the probability; however, the positive LRs were 1.74 and 1.30, respectively.

Conclusions

The prevalence of GAS pharyngitis is extremely low in patients aged < 1 and 1 year, and a BT ≥ 38.0°C is not a predictive symptom. Although a rash and McIsaac score of 4 or 5 are associated with an increased probability, they cannot be used to confirm GAS infection.

Improved Diagnostic Performance of an Immunofluorescence-based Rapid Antigen Detection Test for Group A Streptococci in Children With Pharyngitis

BACKGROUND

Accurate diagnosis and appropriate treatment of group A streptococcal (GAS) pharyngitis are important to prevent complications. Most available rapid antigen detection tests (RADTs) have shown excellent specificity but often lack sensitivity. Our objective was to compare the diagnostic performances of a new fluorescence-based immunoassay and a classic immunochromatographic RADT using standard throat culture or polymerase chain reaction as references.

METHODS

Prospective observational study in 2 pediatric emergency departments in children 3-15 years of age presenting with pharyngitis and a McIsaac score ≥2. Three throat swabs were obtained simultaneously: one for culture and one for each of both RADTs. Polymerase chain reaction assay of the DNaseB sequence was performed in case of discordant results (culture negative and either RADTs positive).

RESULTS

A total of 1002 patients were analyzed, with an overall 37.1% prevalence of GAS pharyngitis. Sensitivity, specificity, positive and negative predictive values were, respectively, 84.9%*, 96.8%, 94.0% and 91.6% for the new fluorescence-based immunoassay, and 75.3%*, 98.1%, 95.9% and 87.0% for the immunochromatographic test (*P < 0.05).

CONCLUSIONS

The immunofluorescence-based assay demonstrated improved diagnostic performances over the standard immunochromatographic RADT. Similarly specific for GAS detection, it demonstrates significantly higher sensitivity in children with McIsaac scores 2 or more. A negative result rules out a risk of GAS pharyngitis in 91.6% of children, making it an appropriate tool in pediatric emergency settings. Combined to the low incidence of rheumatic strains, critical appraisal of current practice to routinely perform a backup throat culture from children with pharyngitis and with negative GAS RADT could be reconsidered.

Evaluation of Simplexa Group A Strep Direct Kit Compared to Hologic Group A Streptococcal Direct Assay for Detection of Group A Streptococcus in Throat Swabs

Diagnosis of bacterial pharyngitis is confirmed by detection of group A Streptococcus (GAS) in patient throat samples. Testing of throat samples has historically relied on culture, but new molecular methods allow much faster test turnaround time (i.e., same day versus 48 to 72 h for culture). Our laboratory uses the Hologic GAS Direct (GASD) assay for screening more than 125,000 throat samples per year. Simplexa GAS Direct is a new real-time quantitative PCR (qPCR) assay that does not require initial DNA extraction. Performance of Simplexa qPCR was compared to GASD. A total of 289 throat swabs were collected from patients attending ambulatory clinics in Calgary, Alberta, Canada. A total of 60 (20.8%) of the samples were initially GAS positive by either method: 54 by both methods, 4 by Simplex qPCR alone, and 2 by GASD alone. An in-house PCR using a unique GAS primer set was used to resolve the 6 discrepant results. Overall, GASD compared to Simplexa qPCR had a sensitivity, specificity, positive predictive value, and negative predictive value of 93.1% versus 100%, 100% versus 100%, 100% versus 100%, and 98.31% versus 100%, respectively. Implementation of Simplexa qPCR in our laboratory setting would cost more but allow the high sample volume to be reported in half the time and save 0.62 medical laboratory technician (MLT) full-time equivalent (FTE). In comparison to culture, the implementation of Simplexa qPCR would save 2.79 medical laboratory assistant (MLA) FTE plus 0.94 MLT FTE. Simplexa qPCR has improved performance and diagnostic efficiency in a high-volume laboratory compared to GASD for GAS detection in throat swabs.

Abdominal pain and nausea in the diagnosis of streptococcal pharyngitis in boys

Objectives

This study was designed to assess the accuracy of gastrointestinal symptoms, including abdominal pain, nausea, and vomiting, in the diagnosis of Group A streptococcal (GAS) pharyngitis in children and to determine differences in diagnostic accuracy in boys versus girls.

Methods

This retrospective cross-sectional study included 5,755 consecutive patients aged <15 years with fever in the electronic database at a primary care practice. Gastrointestinal symptoms were recorded in the database according to the International Classification of Primary Care codes, and the data were extracted electronically. The reference standard was GAS pharyngitis diagnosed with a rapid test. Patients with a clinical diagnosis of probable GAS pharyngitis were excluded from the primary analysis.

Results

Among the 5,755 children with fever, 331 (5.8%) were coded as having GAS pharyngitis, including 218 (65.9%) diagnosed with rapid tests and 113 (34.1%) clinically diagnosed with probable GAS pharyngitis. Among patients with fever and abdominal pain, rapid-test-confirmed GAS pharyngitis was significantly more common in boys (11/120, 9.2%) than in girls (3/128, 2.3%; p=0.026). The positive likelihood ratio of abdominal pain was 1.49 (95% CI =0.88–2.51): 2.41 (95% CI =1.33–4.36) in boys and 0.63 (95% CI =0.20–1.94) in girls. The positive likelihood ratio of nausea was 2.05 (95% CI =1.06–4.00): 2.74 (95% CI =1.28–5.86) in boys and 1.09 (95% CI =0.27–4.42) in girls. The association between abdominal pain and GAS pharyngitis was stronger in boys aged <6 years than in boys aged 6–15 years.

Conclusion

Abdominal pain and nausea were associated with GAS pharyngitis in boys, but not in girls. Abdominal pain and nausea may help determine the suitability of rapid tests in younger boys with fever and other clinical findings consistent with GAS pharyngitis, even in the absence of sore throat.

Palatal Petechiae in the Absence of Group A Streptococcus in Pediatric Patients with Acute-Onset Neuropsychiatric Deterioration: A Cohort Study

BACKGROUND

Palatal petechiae are 95% specific for streptococcal pharyngitis. Despite this, and despite prior research demonstrating that Group A Streptococcus (GAS) is a common antecedent to pediatric acute-onset neuropsychiatric syndrome (PANS) episodes, we anecdotally observed a low rate of documented GAS in patients with PANS and palatal petechiae. This retrospective chart review was conducted to formally report the rate of palatal petechiae and concurrent GAS in a cohort of patients with PANS and investigate other etiologic factors.

METHODS

The clinical notes of 112 patients seen at the Stanford PANS Clinic who met PANS research criteria were reviewed for mention of palatal petechiae. The medical records of patients who demonstrated palatal petechiae on physical examination were reviewed for signs of infection, a clinical history of trauma, and laboratory results that could indicate other causes of petechiae.

RESULTS

Twenty-three patients had documented palatal petechiae on physical examination (ages 5-16, 13/23 [57%] male). Fifteen patients had a rapid GAS test and GAS culture in the Stanford PANS clinic, all with negative results. Evidence of recent GAS infection was found in 8/23 (32%) patients (elevated GAS titers [n = 6] or documentation of a positive rapid GAS test at another facility [n = 2]), one of whom also had potential herpes simplex virus (HSV) infection. One patient had potential HSV infection and recent palatal trauma. No patients had thrombocytopenia. 14/23 (61%) of patients with palatal petechiae had no discernable cause of petechiae. 10/19 (53%) of patients had antihistone antibodies.

CONCLUSIONS

Despite the established relationship between palatal petechiae and GAS, no patient with palatal petechiae in our clinic tested positive for GAS and only 32% had evidence of recent GAS. Most did not have an identifiable cause for the palatal lesions. This finding suggests the potential for alternative causes of palatal petechiae or undetectable GAS in our patient population. The high prevalence of palatal petechiae without GAS infection suggests that the pathogenesis of PANS is multifactorial and may involve disruption or inflammation of the microvasculature. Additional research is needed to further elucidate these findings.

Clinical Management of Pediatric Acute-Onset Neuropsychiatric Syndrome: Part III-Treatment and Prevention of Infections

Objectives: Pediatric acute-onset neuropsychiatric syndrome (PANS) and its subset, pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection (PANDAS), are emerging autoimmune encephalopathies of childhood. Management guidelines are needed. This article, from the PANS/PANDAS Consortium, presents a consensus management guideline for the infection components. Accompanying papers from the Consortium discuss psychiatric and immunomodulatory management. Methods: Literature was reviewed and integrated with the clinical experience of the authors to provide a set of practical guidelines. This article was submitted to all members of the PANS/PANDAS Consortium, and their additional comments were added. Results: The relationships between PANS and infections are reviewed. An approach to the retrospective diagnosis of group A streptococcal infection for an operational definition of PANDAS is proposed. An initial course of anti-streptococcal treatment is proposed for all newly diagnosed PANS cases. Chronic secondary antimicrobial prophylaxis is suggested for children with PANDAS who have severe neuropsychiatric symptoms or recurrent group A Streptococcus-associated exacerbations. Guidelines for children with non-streptococcal PANS include vigilance for streptococcal pharyngitis or dermatitis in the patient and close contacts. All patients with PANS or PANDAS should also be closely monitored for other intercurrent infections, including sinusitis and influenza. Intercurrent infections should be diagnosed and treated promptly according to current standard guidelines. A guideline for the assessment of infection at initial onset or during neuropsychiatric exacerbations is also presented. Standard immunizations and attention to vitamin D are encouraged. Data indicating limited utility of adenotonsillectomy and probiotics are presented. Conclusion: A working guideline for the management of infection issues in PANS and PANDAS, based on literature and expert opinion, is provided.

Efficiency of a clinical prediction model for selective rapid testing in children with pharyngitis: A prospective, multicenter study

Background

There is controversy whether physicians can rely on signs and symptoms to select children with pharyngitis who should undergo a rapid antigen detection test (RADT) for group A streptococcus (GAS). Our objective was to evaluate the efficiency of signs and symptoms in selectively testing children with pharyngitis.

Materials and methods

In this multicenter, prospective, cross-sectional study, French primary care physicians collected clinical data and double throat swabs from 676 consecutive children with pharyngitis; the first swab was used for the RADT and the second was used for a throat culture (reference standard). We developed a logistic regression model combining signs and symptoms with GAS as the outcome. We then derived a model-based selective testing strategy, assuming that children with low and high calculated probability of GAS (<0.12 and >0.85) would be managed without the RADT. Main outcomes and measures were performance of the model (c-index and calibration) and efficiency of the model-based strategy (proportion of participants in whom RADT could be avoided).

Results

Throat culture was positive for GAS in 280 participants (41.4%). Out of 17 candidate signs and symptoms, eight were retained in the prediction model. The model had an optimism-corrected c-index of 0.73; calibration of the model was good. With the model-based strategy, RADT could be avoided in 6.6% of participants (95% confidence interval 4.7% to 8.5%), as compared to a RADT-for-all strategy.

Conclusions

This study demonstrated that relying on signs and symptoms for selectively testing children with pharyngitis is not efficient. We recommend using a RADT in all children with pharyngitis.

Acute exudative tonsillitis in adults: the use of the Centor scoreand some laboratory tests

BACKGROUND/AIM

The aim of our study was to determine the usefulness of the Centor score and some basic laboratory tests (complete blood count and C-reactive protein) for the differential diagnosis of exudative tonsillitis due to Group A &beta;-hemolytic streptococcus (GABHS) or due to non-GABHS agents.

MATERIALS AND METHODS

The data of clinical and laboratory characteristics of the patients diagnosed with exudative tonsillitis were collected and statistically compared between those having positive GABHS throat culture result and those who were negative for any bacterial agent.

RESULTS

Totally 899 adult patients were included in our study; 56 (6.2%) of them were positive for GABHS, while 34 (3.8%) of the cases had a bacterial cause other than GABHS. The remaining 809 (90%) were accepted as non-GABHS cases. The percentages of patients having Centor score of 3 or greater, neutrophilia, lymphocytopenia, and CRP values of greater than 5-fold normal upper reference range were significantly higher in GABHS patients.

CONCLUSION

Centor score of 3 or more together with high CRP, neutrophilia, and lymphocytopenia is predictive for GABHS tonsillopharyngitis.

Operator Influence on Blinded Diagnostic Accuracy of Point-of-Care Antigen Testing for Group A Streptococcal Pharyngitis

Background. Acute pharyngitis caused by Group A Streptococcus (GAS) is a common presentation to pediatric emergency departments (ED). Diagnosis with conventional throat culture requires 18–24 hours, which prevents point-of-care treatment decisions. Rapid antigen detection tests (RADT) are faster, but previous reports demonstrate significant operator influence on performance. Objective. To measure operator influence on the diagnostic accuracy of a RADT when performed by pediatric ED nurses and clinical microbiology laboratory technologists, using conventional culture as the reference standard. Methods. Children presenting to a pediatric ED with suspected acute pharyngitis were recruited. Three pharyngeal swabs were collected at once. One swab was used to perform the RADT in the ED, and two were sent to the clinical microbiology laboratory for RADT and conventional culture testing. Results. The RADT when performed by technologists compared to nurses had a 5.1% increased sensitivity (81.4% versus 76.3%) (p = 0.791) (95% CI for difference between technologists and nurses = −11% to +21%) but similar specificity (97.7% versus 96.6%). Conclusion. The performance of the RADT was similar between technologists and ED nurses, although adequate power was not achieved. RADT may be employed in the ED without clinically significant loss of sensitivity.

The Effect of Rapid Antigen Detection Test on Antibiotic Prescription Decision of Clinicians and Reducing Antibiotic Costs in Children with Acute Pharyngitis

We aimed to investigate the effect of rapid antigen detection test (RADT) in the diagnosis of streptococcal pharyngitis, its impact on antibiotic prescription decision of pediatricians and influence on reduction of antibiotic treatment costs in children with pharyngitis. The study group consisted of 223 patients who were diagnosed with pharyngitis by pediatricians. The sensitivity and specificity of RADT were 92.1% (95% Cl: 78.6-98.3%) and 97.3% (95% Cl: 93.8-99.1%), respectively. In the first assessment, before performing RADT, pediatricians decided to prescribe antibiotics for 178 (79.8%) patients with pharyngitis. After learning RADT results, pediatricians finally decided to prescribe antibiotics for 83 (37.2%) patients with pharyngitis, and antibiotic prescription decreased by 42.6%. Antibiotic costs in non-Group A streptococcus pharyngitis, Group A streptococcus pharyngitis and all subjects groups decreased by 80.8%, 48%, and 76.4%, respectively. Performing RADT in children with pharyngitis has an important impact on treatment decision of clinicians, reduction of unnecessary antibiotic prescriptions and antibiotic costs.

Rapid antigen detection test for group A streptococcus in children with pharyngitis

BACKGROUND

Group A streptococcus (GAS) accounts for 20% to 40% of cases of pharyngitis in children; the remaining cases are caused by viruses. Compared with throat culture, rapid antigen detection tests (RADTs) offer diagnosis at the point of care (within five to 10 minutes).

OBJECTIVES

To determine the diagnostic accuracy of RADTs for diagnosing GAS in children with pharyngitis. To assess the relative diagnostic accuracy of the two major types of RADTs (enzyme immunoassays (EIA) and optical immunoassays (OIA)) by indirect and direct comparison.

SEARCH METHODS

We searched CENTRAL, MEDLINE, EMBASE, Web of Science, CDSR, DARE, MEDION and TRIP (January 1980 to July 2015). We also conducted related citations tracking via PubMed, handsearched reference lists of included studies and relevant review articles, and screened all articles citing included studies via Google Scholar.

SELECTION CRITERIA

We included studies that compared RADT for GAS pharyngitis with throat culture on a blood agar plate in a microbiology laboratory in children seen in ambulatory care.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts for relevance, assessed full texts for inclusion, and carried out data extraction and quality assessment using the QUADAS-2 tool. We used bivariate meta-analysis to estimate summary sensitivity and specificity, and to investigate heterogeneity across studies. We compared the accuracy of EIA and OIA tests using indirect and direct evidence.

MAIN RESULTS

We included 98 unique studies in the review (116 test evaluations; 101,121 participants). The overall methodological quality of included studies was poor, mainly because many studies were at high risk of bias regarding patient selection and the reference standard used (in 73% and 43% of test evaluations, respectively). In studies in which all participants underwent both RADT and throat culture (105 test evaluations; 58,244 participants; median prevalence of participants with GAS was 29.5%), RADT had a summary sensitivity of 85.6%; 95% confidence interval (CI) 83.3 to 87.6 and a summary specificity of 95.4%; 95% CI 94.5 to 96.2. There was substantial heterogeneity in sensitivity across studies; specificity was more stable. There was no evidence of a trade-off between sensitivity and specificity. Heterogeneity in accuracy was not explained by study-level characteristics such as whether an enrichment broth was used before plating, mean age and clinical severity of participants, and GAS prevalence. The sensitivity of EIA and OIA tests was comparable (summary sensitivity 85.4% versus 86.2%). Sensitivity analyses showed that summary estimates of sensitivity and specificity were stable in low risk of bias studies.

AUTHORS' CONCLUSIONS

In a population of 1000 children with a GAS prevalence of 30%, 43 patients with GAS will be missed. Whether or not RADT can be used as a stand-alone test to rule out GAS will depend mainly on the epidemiological context. The sensitivity of EIA and OIA tests seems comparable. RADT specificity is sufficiently high to ensure against unnecessary use of antibiotics. Based on these results, we would expect that amongst 100 children with strep throat, 86 would be correctly detected with the rapid test while 14 would be missed and not receive antibiotic treatment.

Usefulness of Leukocyte Esterase Test Versus Rapid Strep Test for Diagnosis of Acute Strep Pharyngitis

OBJECTIVE

A study to compare the usage of throat swab testing for leukocyte esterase on a test strip(urine dip stick-multi stick) to rapid strep test for rapid diagnosis of Group A Beta hemolytic streptococci in cases of acute pharyngitis in children.

HYPOTHESIS

The testing of throat swab for leukocyte esterase on test strip currently used for urine testing may be used to detect throat infection and might be as useful as rapid strep.

METHODS

All patients who come with a complaint of sore throat and fever were examined clinically for erythema of pharynx, tonsils and also for any exudates. Informed consent was obtained from the parents and assent from the subjects. 3 swabs were taken from pharyngo-tonsillar region, testing for culture, rapid strep & Leukocyte Esterase.

RESULTS

Total number is 100. Cultures 9(+); for rapid strep== 84(-) and16 (+); For LE== 80(-) and 20(+)

STATISTICS

From data configuration Rapid Strep versus LE test don't seem to be a random (independent) assignment but extremely aligned. The Statistical results show rapid and LE show very agreeable results. Calculated Value of Chi Squared Exceeds Tabulated under 1 Degree Of Freedom (P<.0.0001) reject Null HYPOTHESIS and Conclude Alternative Conclusions: Leukocyte esterase on throat swab is as useful as rapid strep test for rapid diagnosis of strep pharyngitis on test strip currently used for urine dip stick causing acute pharyngitis in children.

Multicenter Clinical Evaluation of the Novel Alere i Strep A Isothermal Nucleic Acid Amplification Test

Rapid detection of group A beta-hemolytic streptococcus (GAS) is used routinely to help diagnose and treat pharyngitis. However, available rapid antigen detection tests for GAS have relatively low sensitivity, and backup testing is recommended in children. Newer assays are more sensitive yet require excessive time for practical point-of-care use as well as laboratory personnel. The Alere i strep A test is an isothermal nucleic acid amplification test designed to offer highly sensitive results at the point of care within 8 min when performed by nonlaboratory personnel. The performance of the Alere i strep A test was evaluated in a multicenter prospective trial in a Clinical Laboratory Improvement Amendments (CLIA)-waived setting in comparison to bacterial culture in 481 children and adults. Compared to culture, the Aleri i strep A test had 96.0% sensitivity and 94.6% specificity. Discrepant results were adjudicated by PCR and found the Alere i strep A test to have 98.7% sensitivity and 98.5% specificity. Overall, the Alere i strep A test could provide a one-step, rapid, point-of-care testing method for GAS pharyngitis and obviate backup testing on negative results.