Keywords: Tonsillitis, pharyngitis, diagnosis, Centor criteria modified by MacIsaac, a systematic review

ABSTRACT

Introduction and objective: Acute pharyngotonsillitis of bacterial etiology requires antibiotic treatment, the Centor criteria modified by McIsaac are a useful clinical prediction tool to identify patients with bacterial pharyngotonsillitis whose etiology is caused by Group A Streptococcus β-Hemolyticus. The objective of this review was to synthesize the available and accessible medical evidence on the therapeutic efficacy of the Centor criteria modified by MacIsaac and used for the diagnosis and initiation of antibiotic treatment in acute pharyngotonsillitis in children.

Methodological design: A systematic review was carried out in the MEDILINE database through the PUBMED meta-search engine, using the following thesauri in the search strategy “preschoolers” AND “Diagnosis” AND “Pharyngitis” OR “tonsillitis”. Scientific articles published between 2005-and 2020, without language restriction, with a cross-sectional, cohort, and analytical methodological design were used as inclusion criteria. The following exclusion criteria were used: duplicate studies published outside the study and search period, studies with poor methodological quality after applying the STROBE (STrengthening the Reporting of OBservational studies in Epidemiology) tool.

Results: Nine articles were included, which complied with more than ten items contained in the STROBE tool. The evidence included in two studies mentions the importance of using these criteria as a filter to differentiate patients with bacterial pharyngotonsillitis from viral pharyngotonsillitis, emphasizing their usefulness to support antibiotic prescription in patients. Five articles mention that they should be used in a complementary manner with paraclinical tests to confirm the accurate diagnosis of streptococcal infection. Two investigations showed that anamnesis and examination are important for diagnosis, but not sufficient, evidencing that pediatric patients who met three or more criteria have approximately twice the risk of streptococcal infection.

Conclusions: The likelihood of having a streptococcal infection increases as the Centor criteria as modified by MacIsaac are met so the clinician should record a thorough oropharyngeal examination in the record to assess the presence or absence of these criteria, which should be supplemented by paraclinical tests for an accurate diagnosis.

INTRODUCTION: STATUS OF THE SUBJECT

Acute pharyngotonsillitis of bacterial etiology requires antibiotic treatment, the Centor criteria modified by McIsaac are a useful clinical tool to identify patients with bacterial pharyngotonsillitis whose etiology is caused by Group A Streptococcus β-Hemolyticus. In Nicaragua in health care units, the diagnosis of pharyngotonsillitis is common in clinical practice, which is why the clinical question arises: are the Centor criteria modified by McIsaac useful for the diagnosis, and initiation of antibiotic treatment in acute pharyngotonsillitis in children?

From the following question the PICO variables that will govern the course of this review are broken down:

P Population: children with acute pharyngotonsillitis.

I Intervention: Application of McIsaac’s modified Centor clinical criteria for diagnosis and initiation of antibiotic treatment.

C Comparison: We did not choose to establish a comparison group.

O Results: Therapeutic efficacy.

MATERIAL AND METHODS:

Type of study.

The present investigation has a qualitative type approach being its design a prognostic type systematic review.

Eligibility criteria:

Inclusion criteria.

1. Scientific articles that address the clinical usefulness of the Centor criteria modified by McIsaac for the diagnosis of acute pharyngotonsillitis in children.

2. Scientific articles with descriptive, cross-sectional methodological design (Cohort, case-control).

3. Scientific articles with good methodological quality according to compliance with items contained in the STROBE tool.

4. Gray literature (graduate and postgraduate theses available on the web).

5. Scientific articles published in Spanish and English.

Exclusion criteria

1. Scientific articles that, when critically evaluated, did not meet ten or less of the items contained in the STROBE tool.

2. Duplicate studies without access to download a pdf file.

3. Studies published outside the study period and study and search period.

Sources of information: Primary scientific articles included in this research.

Information search technique

The procedure to access the scientific evidence included in this review was through the use of manual searches using the Google Scholar search engine, identifying the repositories and the database with free online access described below:

Database: MEDLINE through the PubMed search engine: Link https://pubmed.ncbi.nlm.nih.gov/

Repositories:

Universidad Santiago de Guayaquil: http://repositorio.ucsg.edu.ec/

University of Cuenca: https://dspace.ucuenca.edu.ec/

Steps for the execution of the bibliographic search strategy

Step 1 Identification of search terms (thesauri):

Use of the Google meta-search engine, we proceeded to identify the web page of the DeSC (Descriptors in Health Sciences) LINK: http://decs.bvs.br/E/homepagee.htm, where the PICO variables were typed to identify the thesauri (controlled language or search terms) that were subsequently used in the bibliographic search process, taking into account the above, the option “Consult the DeSC” was selected and we proceeded to search for the thesauri.

Step 2 Checking similarities of DeSC descriptors with MeSH descriptors

The search for evidence was carried out in two tools (databases and repositories) whose publication language is English and Spanish, which is why the similarity and discrepancy between the DeSC and MeSH descriptors were checked, and for this purpose, the MEDLINE database was accessed: Link: https://www.ncbi.nlm.nih.gov/mesh/.

After having corroborated the similarities between both descriptors, verifying the number or unique identifier, the search terms used in this review were defined, for which the comparative table shown below demonstrates this procedure:

Step 3 Search string construction and definition

Search string construction: Use of Boolean operators

The logical or Boolean operator (AND) was used as follows in our search strategy “Child, Preschool” AND “Diagnostic” AND “Tonsillitis”.

Step 4 Application of search strategies

The specific MeSH descriptors identified for the search of scientific articles in the MEDLINE database related to the topic under study were first typed into the PubMed search engine independently for each of the MeSH terms and then search strings were performed using Boolean operators. The DeSH terms identified for the search in the institutional repositories were used in the same way as described above.

Bibliographic search period

Study period: last 21 years (2000-2021).

Search date: May 15, 2021 - June 30, 2021.

PRISMA flowchart

Process of selection and exclusion of studies included in this systematic review.

Source: Adapted from the guide of methodological aspects to be evaluated in a systematic review provided by the Catholic University Redemptoris Mater, UNICA (2021).

Bibliographic review method

After the initial search (in the chosen database) and subsequent purging of duplicate references or those that did not contain the variable of interest, the final number of references was identified for the second phase of the review, which consisted of screening the content of the articles by reading the titles and abstracts of the articles and eliminating those articles that were not relevant to the objective of the review.

The methodological quality criteria of each article included were evaluated following the guidelines of the STROBE statement (2009). Each article was evaluated critically and intensively according to pre-established methodological quality parameters and those articles in which ten or more of the items contained in the STROBE (2009) tool were identified were selected, it should be added that for each item identified within the articles a point was assigned, if any characteristic described in the tool has not identified a point was subtracted, at the end the items were added and subtracted to obtain an overall score. Also, the quality of evidence was established for each article using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) method taking as a reference the type of study included in this review.

Data extraction process: Data analysis.

The analysis technique for this systematic review was through the preparation of summary tables, where the most relevant information of each of the articles taken as a sample was consigned, for this purpose, it was evaluated one by one comparing various characteristics or distinctive points among the articles. The design of this summary table of findings was taken from the methodological guide for systematic reviews proposed by the Catholic University Redemptoris Mater (2021) and the guidelines mentioned in the PRISMA statement (2015).

Control of bias among studies.

Publication bias.

We included scientific articles that reflected both positive and negative results.

To minimize selection bias among the included articles.

We excluded those studies that did not meet the eligibility criteria and in the selection phase, the investigators read the abstracts and titles of eligible articles on three occasions in order to identify those that resembled our objective.

RESULTS AND DISCUSSION: SUMMARY OF EVIDENCE:

The complete characteristics of the nine included studies are detailed in Table 1 and 2.

Table 1

Publication data

Table 2

Contents of the publication

A total of 900 articles were identified after applying the search strategy in the MEDLINE database using the PUBMED meta-search engine and two monographic theses (gray literature); scientific evidence that did not meet the eligibility criteria or did not contain the variable of interest was excluded, This left 40 potentially eligible articles which, after being subjected to a critical reading of their content, nine articles were selected to form part of this review (see PRISMA diagram). It is worth mentioning that in the nine articles included in this review, more than ten items described in the STROBE(2009) tool were identified, which shows that they have good methodological quality and their writing follows international guidelines for scientific publication.

Regarding the place where the included evidence was published, two were published in the United States of America and Spain, followed by one article published in Ecuador, Brazil, Poland, Belgium, and Japan, respectively.

Graph 1

Distribution of the sample size reported in the included articles.

Source: information extracted from the scientific articles included in this review and synthesized in the summary tables of findings 1 and 2.

As shown in the tree diagram (Figure 1), the cohorts that included the largest number of participants were those conducted by Noshiyama et al. (2018) and Fine et al. (2012) followed by Fornes et al. (2019), when comparing the results validating the use of the Centor criteria modified by MacIsaac, it was observed that Fine et al. (2012) and Robledo et al. (2019) reported the use of these criteria for the diagnosis of acute pharyngotonsillitis as predictors of Group A beta-hemolytic streptococcus infection; however, both investigations emphasized the importance of using these criteria as a filter to differentiate patients with pharyngotonsillitis of bacterial etiology from viral etiology, emphasizing that these criteria are of clinical utility to support antibiotic prescription in patients and should therefore be detailed in the medical consultation in the clinical record.

According to the distribution of age averages calculated and reported in the research conducted by Fornes et al. (2019), Cifuentes and Jaramillo (2020), Mazur et al. (2014), Roggen et al. (2013), and Brennan et al. (2018), pediatric patients affected by acute pharyngotonsillitis of bacterial etiology predominate in an age range of 3 to 8 years and boys are more affected than girls (only two of the six articles identified prevalence in girls over boys) this study provides valuable information showing that cases are concentrated in the first years of life, especially at school age which allows us to emphasize prevention measures in this age group.