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Rapid Molecular Detection and Differentiation of Influenza Viruses A and B
Published on: January 30, 2017
Clinical differences of influenza subspecies among hospitalized children
Manolya Acar1, Murat Sütçü1, Hacer Aktürk1
1Department of Pediatrics, Pediatric Infectious Diseases and Clinical Immunology Division, İstanbul University İstanbul School of Medicine, İstanbul, Turkey.
Insights
Influenza A/H1N1 infection in children often presents with more severe clinical disease compared to other influenza subtypes. Understanding these differences is crucial for effective diagnosis and treatment of pediatric influenza cases.
Area of Science:
- Pediatric Infectious Diseases
- Virology
- Clinical Medicine
Background:
- Influenza subspecies exhibit varying clinical presentations, mortality, and morbidity.
- Physician awareness of these differences aids in selecting appropriate diagnostic and therapeutic strategies.
- Early recognition of potential complications is vital for managing pediatric influenza.
Purpose of the Study:
- To compare the clinical manifestations of different influenza subspecies in hospitalized children.
- To identify specific risk factors and disease severity associated with each influenza strain.
- To inform clinical decision-making for pediatric influenza management.
Main Methods:
- A retrospective study of hospitalized children with confirmed influenza infection via polymerase chain reaction (PCR).
- Patients were categorized into three groups: Influenza A/H1N1, Influenza A/H3N2, and Influenza B.
- Data collected included demographics, symptoms, comorbidities, laboratory findings, and clinical outcomes.
Main Results:
- Influenza A/H1N1 was more prevalent in children with chronic neurologic disorders, while H3N2 was associated with renal failure.
- Common symptoms included fever, cough, and difficulty breathing; non-respiratory findings involved lymphadenopathy and gastrointestinal issues.
- Influenza A/H1N1 infection was linked to more severe outcomes, including higher rates of leukopenia, thrombocytopenia, neutropenia, elevated CRP, and antibiotic use, with two deaths reported.
Conclusions:
- Influenza A/H1N1 infection is associated with more severe clinical disease in hospitalized children.
- Recognizing subtype-specific differences in pediatric influenza is essential for clinical management.
- Further research into the distinct pathogenic mechanisms of influenza strains is warranted.
Aim:
Clinical findings, mortality, and morbidity rates differ among influenza subspecies. Awareness of these differences will lead physicians to choose the proper diagnostic and therapeutic strategies and to foresee possible complications. The aim of this study was to evaluate the clinical differences of influenza subspecies among hospitalized children.
Material And Methods:
Hospitalized children with proven influenza infection by polymerase chain reaction on nasopharyngeal swab specimens in our clinic, between December 2013 and March 2016, were enrolled. These children were divided into 3 groups as Influenza A/H1N1 (n=42), Influenza A/H3N2 (n=23), and Influenza B (n=35).
Results:
The median age of the children was 51.5 months (range, 3-204 months). The most common presenting symptoms were fever (n=83), cough (n=58), and difficulty in breathing (n=25). The most common non-respiratory findings were lymphadenopathy (n=18) and gastrointestinal system involvement (n=17). Sixty-two percent of the patients (n=62) had chronic diseases. H1N1 and H3N2 were significantly more common among patients with chronic neurologic disorders and renal failure, respectively. Leukopenia (n=32) and thrombocytopenia (n=22) were the most common pathologic laboratory findings. Neutropenia, elevated CRP levels, and antibiotic use were significantly more common among patients with H1N1 infection. Seven patients were transferred to the intensive care unit with diagnoses of acute respiratory distress syndrome (n=4), encephalitis (n=2), and bronchiolitis (n=1). Two patients with chronic diseases and H1N1 infection died secondary to acute respiratory distress syndrome.
Conclusions:
Influenza A/H1N1 infection represented more severe clinical disease.
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