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[Dynamic changes of T-lymphocytes and immunoglobulins in patients with severe acute respiratory syndrome]
Objective:
To study the immunological changes in patients suffered from severe acute respiratory syndrome (SARS).
Methods:
T-lymphocyte subsets of peripheral blood from 124 patients with different phases of SARS were measured by flow cytometry. Immunoglobulins were examined simultaneously. Blood specimens from 51 patients with AIDS and 57 normal persons were collected as controls and subjected to the same measurements.
Results:
The levels of CD3(+), CD4(+) and CD8(+) T-lymphocytes in SARS group [(589 +/- 435) x 10(6)/L, (316 +/- 267) x 10(6)/L and (215 +/- 165) x 10(6)/L, respectively] were significantly lower than those of the normal group (P < 0.01). When compared the SARS group with AIDS group, we found the level of CD4(+) T-lymphocyte in the former was higher (P < 0.01), while the CD3(+) and CD8(+) T-lymphocytes were lower (P < 0.01). There were 54 (44%) patients in SARS group and 39 (76%) patients in AIDS group showed low levels of CD4(+) T-lymphocyte (< 200 x 10(6)/L). The count of T-lymphocyte subsets of SARS group decreased to the lowest level during the 10(th) and 12(th) day after the onset of symptoms. Both serum IgG and IgE in SARS group [(15.1 +/- 8.5) g/L and (0.6 +/- 0.9) g/L, respectively] were higher than those of the normal group.
Conclusion:
The levels of CD3(+), CD4(+) and CD8(+) T-lymphocyte subsets in peripheral blood of SARS patients decrease significantly and go down to the lowest point at days 10 approximately 12 after onset of the disease.
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