How critical is timing for the diagnosis of influenza in general practice?

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State: Public
Version: Final published version
Serval ID
serval:BIB_B919E2FA4C17
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
How critical is timing for the diagnosis of influenza in general practice?
Journal
Swiss Medical Weekly
Author(s)
Senn N., Favrat B., D'Acremont V., Ruffieux C., Genton B.
ISSN
1424-7860 (Print)
ISSN-L
0036-7672
Publication state
Published
Issued date
2005
Peer-reviewed
Oui
Volume
135
Number
41-42
Pages
614-617
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Abstract
QUESTIONS UNDER STUDY: The diagnostic significance of clinical symptoms/signs of influenza has mainly been assessed in the context of controlled studies with stringent inclusion criteria. There was a need to extend the evaluation of these predictors not only in the context of general practice but also according to the duration of symptoms and to the dynamics of the epidemic.
PRINCIPLES: A prospective study conducted in the Medical Outpatient Clinic in the winter season 1999-2000. Patients with influenza-like syndrome were included, as long as the primary care physician envisaged the diagnosis of influenza. The physician administered a questionnaire, a throat swab was performed and a culture acquired to document the diagnosis of influenza.
RESULTS: 201 patients were included in the study. 52% were culture positive for influenza. By univariate analysis, temperature >37.8 degrees C (OR 4.2; 95% CI 2.3-7.7), duration of symptoms <48 hours (OR 3.2; 1.8-5.7), cough (OR 3.2; 1-10.4) and myalgia (OR 2.8; 1.0-7.5) were associated with a diagnosis of influenza. In a multivariable logistic analysis, the best model predicting influenza was the association of a duration of symptom <48 hours, medical attendance at the beginning of the epidemic (weeks 49-50), fever >37.8 and cough, with a sensitivity of 79%, specificity of 69%, positive predictive value of 67%, negative predictive value of 73% and an area under the ROC curve of 0.74.
CONCLUSIONS: Besides relevant symptoms and signs, the physician should also consider the duration of symptoms and the epidemiological context (start, peak or end of the epidemic) in his appraisal, since both parameters considerably modify the value of the clinical predictors when assessing the probability of a patient having influenza.
Keywords
Adult, Family Practice, Female, Humans, Influenza, Human/diagnosis, Male, Middle Aged, Prospective Studies, Questionnaires, Switzerland, Time Factors
Pubmed
Web of science
Create date
29/02/2008 11:34
Last modification date
20/08/2019 15:27
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