Korean J Intern Med.  2018 Mar;33(2):391-396. 10.3904/kjim.2016.226.

Late diagnosis of influenza in adult patients during a seasonal outbreak

• Choi SH
• Chung JW
• Kim T
• Park KH
• Lee MS
• Kwak YG

• KMID: 2411551
• DOI: http://doi.org/10.3904/kjim.2016.226

Abstract

BACKGROUND/AIMS
Due to advances in diagnostic techniques, clinicians are more frequently performing influenza diagnostic tests and referring to their test results ahead of the administration of neuraminidase inhibitors (NAIs). To investigate the clinical significance of the time from symptom onset to laboratory diagnosis, we reviewed the clinical characteristics of adult patients with influenza who had an early laboratory diagnosis (ED) or a late laboratory diagnosis (LD) at one of four tertiary care centers during a seasonal outbreak of influenza.
METHODS
Clinical data were collected from 1,405 adults during the 2013 to 2014 influenza season. A patient was regarded as receiving an ED or LD if he/she received an influenza diagnostic test at 0 to 1 or 4 to 7 days after symptom onset, respectively. Early NAI therapy and late NAI therapy were defined as the administration of NAI ≤ 2 or > 2 days after symptom onset, respectively.
RESULTS
Nearly half of the patients (47.0%) received an ED (n = 661), whereas 13.5% (n = 190) received a LD. Patients with a LD had initial symptoms of cough, sputum production, and dyspnea and experienced pneumonia, antibiotic therapy, hospitalization, and admission to the intensive care unit more often than those with an ED. NAI therapy and early NAI therapy were less frequent in patients with a LD than those with an ED. Of the analyzed baseline characteristics, age ≥ 50 years, influenza B infection, and diagnosis using a polymerase chain reaction test were significantly associated with a LD.
CONCLUSIONS
LD was associated with inappropriate antiviral therapy and complicated presenting features in adult patients with seasonal influenza. ED of influenza should be emphasized, especially for older adults.

Keyword

Influenza, human; Diagnosis; Antiviral agents

MeSH Terms

Adult*
Antiviral Agents
Clinical Laboratory Techniques
Cough
Delayed Diagnosis*
Diagnosis
Diagnostic Tests, Routine
Dyspnea
Hospitalization
Humans
Influenza, Human*
Intensive Care Units
Neuraminidase
Pneumonia
Polymerase Chain Reaction
Seasons*
Sputum
Tertiary Care Centers
Antiviral Agents
Neuraminidase