Sir, the problem of emerging H7N9 bird flu is an important world problem. Focusing on the clinical presentation, there are various manifestations as well as laboratory parameter disorder [1]. Focusing on hematological parameters, an important forgotten finding is anemia. Based on the present knowledge, there is still no specific report considering anemia in the patients with H7N9 bird flu. In fact, anemia is identified as an important clinical finding in the previous well-known emerging H5N1 bird flu [2]. Focusing on the present H7N9 bird flu, based on 7 patients with complete data on hemoglobin (Hb < 12 g/dL) in the reports by Chen et al. [3] and Jie et al. [4], the prevalence of anemia can be detected at 42.9 % (3/7), which seems to be very high. However, focusing on anemic cases, no cases had hemoglobin level less than 10 g/dL. Of interest, all cases with identified anemia ended up with death and no case with no anemia died.
Based on these data, it might seem that the anemia is a common problem in H7N9 bird flu and might have some clinical relationship to poor outcome. Nevertheless, the detected anemia might be an underlying disease of the infected cases or might be a problem induced by viral infection. Further study on the pathobiology of anemia and its clinical importance in H7N9 bird flu is warranted.
Contributor Information
Somsri Wiwanitkit, Email: somsriwiwan@hotmail.com.
Viroj Wiwanitkit, Email: wviroj@yahoo.com.
References
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