OBJECTIVE To explore the expressions of NOD-like receptor heat protein domain associated protein 3 (NLRP3) signaling pathways and related inflammatory cytokines in the patients with severe pneumonia and analyze the diagnostic values.

METHODS A total of 216 patients with pneumonia who were treated in the Second People′s Hospital of Jiaozuo City from Jan 2020 to Jan 2023 were assigned as the study group and were divided into the severe group with 113 cases and the mild group with 103 cases according to the severity of disease. Meanwhile, 216 healthy people who received physical examination were chosen as the control group. The levels of peripheral blood NLRP3, cysteine proteinase-1 (Caspase-1), interleukin (IL)-1β, IL-18, serum amyloid protein A (SAA) and monocyte chemoattractant protein (MCP) were detected for the patients. Spearman correlation analysis was performed for the association between the indexes and the severity of illness condition, and the values of the indexes in diagnosis of severe pneumonia were analyzed by means of receiver operating characteristic (ROC) curves.

RESULTS The levels of NLRP3, Caspase-1, IL-1β, IL-18, SAA and MCP-1 of the study group were significantly higher than those of the control group(P < 0.05); the levels of NLRP3, Caspase-1, IL-1β, IL-18 and MCP-1 of the severe group were significantly higher than those of the mild group (P < 0.05), and the expression levels of the indexes were positively correlated with the severity of illness condition(P < 0.05). The area under curve (AUC) of the joint detection of the indexes was 0.933 in diagnosis of the severe pneumonia, with the sensitivity 90.27%, the specificity 82.52%.

CONCLUSION The patients with severe pneumonia show high expression levels of NLRP3, Caspase-1, IL-1β, IL-18 and MCP-1, which are positively correlated with the severity of illness condition. The joint detection of the indexes may raise the diagnostic value of the severe pneumonia patients.