Objective  To explore the correlation between the levels of long non-coding ribonucleic acid （lncRNA） H19 and histone deacetylase （HDAC） 2 in peripheral blood and the degree of infection and prognosis in patients with sepsis.

Methods  From February 2020 to May 2022, 142 hospitalized septic patients were regarded as study subjects. According to the severity of disease infection, they were assigned into three groups of mild （n=61）, moderate（n=45） and shock（n=36）. And two groups of death（n=28） and survival（n=114） were also assigned according to the follow-up results. The levels of lncRNA H19 and HDAC2 in peripheral blood were detected, Sequential Organ Failure Assessment （SOFA） and Acute Physiology And Chronic Health Evaluation Ⅱ（APACHE Ⅱ） were utilized for evaluating the prognosis of patients. Pearson’s analysis was performed for examining the correlation between the levels of lncRNA H19 and HDAC2 in peripheral blood and the scores of SOFA and APACHE Ⅱ. Receiver operating characteristic （ROC） curve was plotted for predicting the diagnostic value of the peripheral blood levels of lncRNA H19 and HDAC2.

Results  lncRNA H19 levels in peripheral blood were （1.07 ± 0.25） in mild group, （2.67 ± 0.69） in moderate group and （4.85 ± 1.36） in shock group; SOFA score was （4.63 ± 0.91） points in mild group, （7.43 ± 1.32） points in moderate group and （9.05 ± 1.84） points in shock group; APACHEⅡ score was （11.59 ± 2.06） points in mild group, （15.74 ± 3.12） points in moderate group and （19.14 ± 3.68） points in shock group; HDAC2 level was （2.96 ± 0.71） ng/L in mild group, （1.79 ± 0.43） ng/L in moderate group and （1.12 ± 0.26） ng/L in shock group. The peripheral blood level of lncRNAH19 was lower in survival group than that in death group （1.92 ± 0.47） vs （5.05 ± 1.44）, P＜0.05 and the level of HDAC2 was higher than that of death group （2.41 ± 0.34）ng/L vs （0.95 ± 0.16） ng/L, P＜0.05. The peripheral blood level of lncRNA H19 was correlated positively with SOFA/APACHE Ⅱ score （P＜0.05）. And the peripheral blood level of HDAC2 was correlated negatively with SOFA/APACHE Ⅱ score （P＜0.05）. ROC results indicated that area under the curve （AUC） of lncRNA H19 level alone in the diagnosis of septic patients was 0.869 with a sensitivity of 69.23% and a specificity of 91.23%; AUC of HDAC2 level alone in diagnosing sepsis was 0.861 with a sensitivity of 73.08% and a specificity of 86.84%; AUC（0.942） of sepsis prognosis assessed by both methods was obviously higher than that assessed by lncRNA H19 alone （Z=2.453, P=0.014） and HDAC2 alone （Z=2.066, P=0.039）.

Conclusion  The levels of lncRNA H19 and HDAC2 in peripheral blood are correlated closely with the severity of infection in septic patients and have a high predictive value for outcomes.