Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

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

Pallon, Jon LU ; Rööst, Mattias LU ; Sundqvist, Martin and Hedin, Katarina LU (2021) In BMC Infectious Diseases 21(1).
Abstract

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... (More)

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.

(Less)
Please use this url to cite or link to this publication:
author
; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Group A streptococci, Pharyngotonsillitis, Predictive values, Primary health care, Symptoms
in
BMC Infectious Diseases
volume
21
issue
1
article number
971
publisher
BioMed Central (BMC)
external identifiers
  • scopus:85115162468
  • pmid:34535115
ISSN
1471-2334
DOI
10.1186/s12879-021-06665-9
language
English
LU publication?
yes
id
8406fbf8-914d-4dd5-ba20-8c1f1bb59960
date added to LUP
2021-10-01 12:12:16
date last changed
2024-06-15 17:12:21
@article{8406fbf8-914d-4dd5-ba20-8c1f1bb59960,
  abstract     = {{<p>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 &lt; 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.</p>}},
  author       = {{Pallon, Jon and Rööst, Mattias and Sundqvist, Martin and Hedin, Katarina}},
  issn         = {{1471-2334}},
  keywords     = {{Group A streptococci; Pharyngotonsillitis; Predictive values; Primary health care; Symptoms}},
  language     = {{eng}},
  number       = {{1}},
  publisher    = {{BioMed Central (BMC)}},
  series       = {{BMC Infectious Diseases}},
  title        = {{The aetiology of pharyngotonsillitis in primary health care : a prospective observational study}},
  url          = {{http://dx.doi.org/10.1186/s12879-021-06665-9}},
  doi          = {{10.1186/s12879-021-06665-9}},
  volume       = {{21}},
  year         = {{2021}},
}