Dynamic changes of lymphocyte counts in adult patients with severe pandemic H1N1 influenza A.
BACKGROUND
Lymphopenia has been observed in severe pandemic influenza A/H1N1 in developed countries. However, data from developing countries are rare and dynamic change of lymphocyte counts in severe pandemic influenza A/H1N1 is scarcely reported. This study aimed to observe change of lymphocyte counts in patients with severe pandemic influenza A/H1N1 and to investigate the correlation of lymphopenia and severe pandemic influenza A/H1N1.


METHODS
We retrospectively analyzed the white blood cell counts and differentials and other clinical data in 21 hospitalized patients with severe pandemic influenza A/H1N1 confirmed by reverse-transcription PCR during 2009 and 2010.


RESULTS
All patients, except two cases with bacterial co-infections, had normal or reduced white blood cell counts. Seventeen (81.0%) patients had decreased lymphocyte proportions (<20%) and counts (<0.8×109/L), with the lowest value of 1.2% and 0.1×109/L respectively. A patient with nosocomial infection of influenza A/H1N1 showed that lymphopenia occurred on the first day of illness. Lymphocyte proportions and absolute counts returned to normal or slightly higher than normal in 16 of the 17 patients within 2-3weeks after the disease onset.


CONCLUSIONS
Lymphopenia along with other clinical parameters may be helpful in early differential diagnosis of severe pandemic influenza A/H1N1.
['Cheng|Yandong|Y|', 'Zhao|Hong|H|', 'Song|Peixin|P|', 'Zhang|Zhaoping|Z|', 'Chen|Junhao|J|', 'Zhou|Yi-Hua|YH|']
D000293:Adolescent D000328:Adult D000368:Aged D000369:Aged, 80 and over D005260:Female D006801:Humans D053118:Influenza A Virus, H1N1 Subtype D007251:Influenza, Human D018655:Lymphocyte Count D008214:Lymphocytes D008231:Lymphopenia D008297:Male D008875:Middle Aged D012189:Retrospective Studies D055815:Young Adult
Lymphopenia Severe pandemic influenza A/H1N1 Pneumonia Virus