THE CORRELATION BETWEEN SERUM CD4+ CD25+ TREG CELLS, HMGB1, LAC, AND ENDOTOXIN LEVELS AND THE SEVERITY OF SEVERE PNEUMONIA COMPLICATED WITH SEPSIS

Yingfeng Zhuang^{1, 2, *}, Songchang Shi²

¹Shengli Clinical Medical College of Fujian Medical University, Fuzhou, PR China - ²Department of Critical Care Medicine, Fujian Provincial JINSHAN Hospital, Fuzhou, PR China

Objective: To investigate how the levels of CD₄⁺ CD₂₅⁺ regulatory T lymphocytes (CD₄⁺ CD₂₅⁺ Treg), high mobility group protein B1 (HMGB1), blood lactate (Lac) and endotoxin (ET) correlate with the severity of severe pneumonia with sepsis. 

Methods: 68 patients with severe pneumonia and sepsis admitted to our hospital from March 2018 to June 2019 were randomly selected as the study sample, and 68 healthy subjects who had physical examinations in our hospital at the same time were selected as the control group. According to their prognoses, the patients were divided into a survival group (51 cases) and a death group (17 cases). The clinical data, Acute Physiology and Chronic Health Evaluation (APACHE II) score, serum CD₄⁺ CD₂₅⁺ Treg cells, HMGB1, Lac and ET levels were compared. Pearson correlation test was used to analyze the correlation between serum CD₄⁺ CD₂₅⁺ Treg cells, HMGB1, Lac and ET levels and the severity of severe pneumonia with sepsis. 

Results: The respiratory rate, heart rate, body temperature and leukocyte count in the study group were significantly higher than those in the control group, and the platelet count was significantly lower than that in the control group (P<0.01). Compared with the control group, the levels of CD₄⁺ CD₂₅⁺ Treg cells, HMGB1, Lac, ET and APACHE Ⅱ in the study group were significantly higher (P<0.01). Compared with the survival group, the levels of CD₄⁺ CD₂₅⁺ Treg cells, HMGB1, Lac, ET and APACHE Ⅱ in the dead group were significantly higher (P<0.01). According to Pearson correlation analysis, the levels of CD₄⁺ CD₂₅⁺ Treg cells, HMGB1, Lac and ET in serum were positively correlated with APACHE II score, which means they were positively correlated with the severity of severe pneumonia complicated with sepsis (P<0.05). 

Conclusion: The levels of serum CD₄⁺ CD₂₅⁺ Treg cells, HMGB1, Lac and ET are significantly correlated with the severity of severe pneumonia complicated with sepsis, which can be used as an important index to judge the severity of illness and the prognosis of patients.