Abstract
Oseltamivir is the drug of choice for patients with pandemic influenza (H1N1 2009). However, sporadic cases of oseltamivir resistance have been described worldwide. Up to March 2010, a total of 11 strains (2.2% of tested isolates) of oseltamivir-resistant pandemic influenza (H1N1 2009) have been discovered in South Korea. We report a case of 46-year-old man with acute myeloid leukemia in whom an oseltamivir-resistant pandemic (H1N1) 2009 virus was isolated. Despite high dose oseltamivir therapy for 10 days he had persistent symptoms and showed positive results in repeated real-time RT-PCR for pandemic influenza (H1N1 2009) virus from nasopharyngeal specimen. The patient improved eventually after oseltamivir was replaced by zanamivir inhalation.
Figures and Tables
Figure 1
Chest radiograph (left) and contrast-enhanced CT scan (right) show a focal consolidation on middle lobe area of right lung (arrow) on the 5th day of admission
![ic-42-107-g001](/upload/SynapseData/ArticleImage/0086ic/ic-42-107-g001.jpg)
Figure 3
Oseltamivir resistant genetic substitution in NA (neuraminidase) of pandemic influenza A (H1N1 2009) viruses from the patient's nasopharyngeal specimen on hospital day 17. NA gene sequence product was generated by RT-PCR and directly sequenced. Nucleotide sequence TAC (encoding tyrosine) in box exhibits that the viruses contain oseltamivir resistant maker (Y275) on their NA. In the figure, single letters and numbers denote abbreviations of individual amino acids and amino acid sequences numbering, respectively.
![ic-42-107-g003](/upload/SynapseData/ArticleImage/0086ic/ic-42-107-g003.jpg)
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