2009 H1N1 influenza virus and immunosuppressive drug

Wiwanitkit, Viroj

doi:10.1590/S0066-782X2010001600018

LETTER TO THE EDITOR

Wiwanitkit House, Bangkhae, Bangkok Tailândia 10160

Mailing address

Keywords: Influenza A virus, H1N1 Influenza; immunosuppressive agents; heart transplantation.

Dear Editor,

I read the recent report on 2009 H1N1 influenza virus and immunosuppressive drug with great interest¹. Bacal et al² concluded that "The present report is, to our knowledge, the first on a heart transplant patient who developed H1N1 virus infection and had a favorable outcome, thus generating discussion on the real role of immunosuppressive therapy as a risk factor for the severe form of the disease¹". Based on this study, I agree that this is a successful treatment of the swine flu in a heart transplant patient. It can imply that the heart transplant patient can be infected with the new virus. However, due to the limited number of subjects, it might not be possible to propose anything related to the immunosuppressive therapy, although there has been some recent evidence supporting this assertion².

Answer to the letter

In the case report "Influenza A H1N1 pneumonia in an immunosuppressed patient after heart transplantation", we presented a report on a heart transplant patient with a good clinical outcome after pulmonary infection caused by H1N1 Influenza virus. In the medical literature, the present recommendation is to be cautious about serious complications of the infection and about the possibility of prolonged viral shedding. However, since it is a recently described disease, definitive data concerning the mechanisms of the disease and to which extent the immune response can contribute to the worsening of such disease is not well known, as well as the influence of immunosuppression in this context. In conclusion, we also consider that it is too premature to recommend any immunomodulatory or suppressive treatment for the swine flu.

References

¹
Centers for Diseases Control and Prevention. Updated interim recommendations: special considerations for clinicians regarding 2009 H1N1 influenza in severely immunosuppresed patients (on line). [Acessed on 2010 Sept 13]. Available from: http://www.cdc.gov/h1n1flu/immunosuppresion/
2. Bacal F, Seguro LF, Ogawa T, Mangini S, Fiorelli AI, Bocchi E. Pneumonia por influenza A (H1N1) em paciente imunossuprimido após transplante cardiac. Arq Bras Cardiol. 2009; 93 (6): e104-e106.