There is no association between serum endotoxin levels and inflammation in asthma

Endotoxin, in lipopolysaccharide structure (LPS), is the main component of the outer membrane of gram negative bacteria. LPS levels were associated with inflammatory disease. Asthma is a chronic inflammatory disease involving many different cell types and cellular elements. The association between LPS serum levels and the asthma is not well known. The aim of this study was to investigate the association between the LPS serum levels and the severity of asthma, demographic data and laboratory parameters.

The study included 67 patients aged >18 years with a diagnosis of asthma, and 15 healthy volunteers with no history of chronic disease as a control group. The Asthma Control Test (ACT), Respiratory Function Tests (RFTs), fractional exhaled nitric oxide (FeNO), and endotoxin levels were measured and compared between the groups. The endotoxin measurements were performed using the ELISA method.

The mild-moderate asthma group included 33 patients and the severe asthma group, 34 patients. The endotoxin level was measured as 17.78 (range 3.59 to 304.55) EU/ml in the patient group and 15 (range 4.01 to 74.06) EU/ml in the control group with no statistically significant difference determined between the groups. In the subgroups, the endotoxin level was measured as 15.21 (range 3.69 to 304.55) EU/ml in the mild-moderate group and 14.46 (range 3.59 to 278.86) EU/ml in the severe asthma group with no statistically significant difference determined between the groups.

The results of this study showed no relationship between serum endotoxin level and asthma or asthma severity.