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

Systematic review and meta-analysis of the accuracy of McIsaac and Centor score in patients presenting to secondary care with pharyngitis

BACKGROUND

Centor and McIsaac scores are clinical prediction rules for diagnosing group A streptococcus (GAS) infection in patients with pharyngitis. Their recommended thresholds vary between guidelines.

OBJECTIVES

To estimate the sensitivity and specificity of the McIsaac and Centor scores to diagnose GAS pharyngitis and evaluate their impact on antibiotic prescribing at each threshold in patients presenting to secondary care.

DATA SOURCES

MEDLINE, Embase, and Web of Science were searched from inception to September 2022.

STUDY ELIGIBILITY CRITERIA

Studies of patients presenting with acute pharyngitis to emergency or outpatient clinics that estimated the accuracy of McIsaac or Centor scores against throat cultures and/or rapid antigen detection tests (RADT) as reference standards.

TESTS

Centor or McIsaac score.

REFERENCE STANDARD

Throat cultures and/or RADT.

ASSESSMENT OF RISK OF BIAS

Quality Assessment of Diagnostic Accuracy Studies.

METHODS OF DATA SYNTHESIS

The sensitivities and specificities of the McIsaac and Centor scores were pooled at each threshold using bivariate random effects meta-analysis.

RESULTS

Fourteen studies were included (eight McIsaac and six Centor scores). Eight studies had unclear and six had a high risk of bias. The McIsaac score had higher estimated sensitivity and lower specificity relative to Centor scores at equivalent thresholds but with wide and overlapping confidence regions. Using either score as a triage to RADT to decide antibiotic treatment would reduce antibiotic prescription to patients with non-GAS pharyngitis relative to RADT test for everyone, but also reduce antibiotic prescription to patients with GAS.

DISCUSSION

Centor and McIsaac scores are equally ineffective at triaging patients who need antibiotics presenting with pharyngitis at hospitals. At high thresholds, too many true positive cases are missed, whereas at low thresholds, too many false positives are treated, leading to the over prescription of antibiotics. The former may be compensated by adequate safety netting by clinicians, ensuring that patients can seek help if symptoms worsen.

Useful manifestations to detect adenovirus in children with upper respiratory infections: A retrospective study

OBJECTIVE

Approximately 1 million adenovirus immunochromatography (IC) kits are annually used in Japan. However, no practical strategies have been developed regarding their use for detecting adenovirus. The present study aims to verify the usefulness of clinical manifestations in making decisions regarding the use of adenovirus IC kits for children with upper respiratory infections (URI).

METHODS

The medical records of 825 pediatric cases tested by IC kits for adenovirus were extracted from clinical laboratory department database over a 3-year period at our hospital. Among them, 585 patients were suspected adenovirus URI, and their clinical manifestations were reviewed. After data cleaning, 10 types of clinical manifestations were statistically analyzed between adenovirus IC kit-positive and -negative groups. Multivariate analysis was performed to select significant clinical manifestations using adenovirus IC kit positivity as the objective variable.

RESULTS

Among 585 pediatric patients, the cases of 420 patients, with suitable data for whom no other pathogen was detected, were reviewed. Adenovirus was detected in 86 cases. Multivariate analysis identified a significant difference for three clinical manifestations: (1) fever ≥ 39.0°C, (2) rhinorrhea, and (3) tonsillar exudate. The negativity rate for the IC kit was 90% when none of the three manifestations was observed.

CONCLUSIONS

The results suggested that IC kits for adenovirus tend to give negative results in cases that lack all the three above mentioned clinical manifestations.