Complicated secondary pneumonia after swine-origin infuenza a virus infection in an immunocompetent patient

Ryotaro Igusa, Tomohiro Sakakibara, Taizo Shibahara, Kazuhiro Sakamoto, Hidekazu Nishimura, Kozo Ota

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)


The pandemic of the swine-origin infuenza A virus (S-OIV) in 2009 demonstrated severe viral pneumonia followed by acute respiratory distress syndrome (ARDS). Although ARDS would be caused by the influenza virus pneumonia itself, it has remained unclear whether other respiratory viral or bacterial infections coexist with S-OIV pneumonia. We report an immunocompetent patient with methicillin-resistant Staphylococcus aureus (MRSA) and Herpes simplex virus (HSV) pneumonia secondary to S-OIV infection. A 57-year-old man previously without major medical illness was admitted to our hospital with severe pneumonia accompanied by ARDS due to S-OIV. In his clinical course, anti-infuenza treatment was not effective. Sputum culture revealed the presence of MRSA, and HSV was isolated in broncho-alveoler lavage (BAL) fuid. Administration of an antiviral agent (acyclovir), an antibacterial agent (linezolid), and a corticosteroid (methylprednisolone) successfully improved the pneumonia and ARDS. HSV pneumonia can scarcely be seen in healthy people. However recently it has been recognized as a ventilator-associated pneumonia. Although coexistence of Streptococcus pneumoniae and MRSA was reported in S-OIV pneumonia, secondary viral infection has not been reported. The present report is the frst patient with HSV pneumonia secondary to S-OIV infection. We propose that a possibility of hidden HSV pneumonia should be taken into consideration in patients with prolonged severe pneumonia due to infuenza infection.

Original languageEnglish
Pages (from-to)117-120
Number of pages4
JournalTohoku Journal of Experimental Medicine
Issue number2
Publication statusPublished - 2012
Externally publishedYes


  • Acute respiratory distress syndrome
  • Herpes simplex virus pneumonia
  • Methicillin-resistant Staphylococcus aureus
  • Swine-origin infuenza virus
  • Ventilator-associated pneumonia

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)


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