OBJECTIVETo explore the biomarkers and inflammatory characteristics for microcosmic syndrome differentiation of cold-phlegm syndrome (CPS) and heat-phlegm syndrome (HPS) in patients with bronchial asthma.

METHODSPatients with bronchial asthma of chronic persistent condition were distributed into three groups according syndrome differentiation, the CPS group (27 patients), the HPS group (32 patients) and the non-cold/heat-phlegm syndrome group (NP group, 31 patients), besides, a control group was setup with 33 healthy persons. Percentages of neutrophils and eosinophils (NEU, EOS) in sputum sample (collected by induction) and peripheral blood were counted; and levels of interleukin-8, -5, and -4 (IL-8, IL-5 and IL-4), interferon-gamma (IFN-gamma), leukotriene B4 (LT-B4), eosinophil cationic protein (ECP), and C-reactive protein (CRP) in sputum supernatant and serum were determined by enzyme-linked immunosorbent assay.

RESULTSPercentage of NEU in sputum of HPS group was higher than that in the other three groups (P < 0.05); while percentages of EOS in serum and sputum of CPS group were higher than that in the other three groups (all P < 0.01). Level of ECP (a parameter closely associated with EOS) also was high in the CPS group, but IL-8 (a parameter closely associated with NEU) showed no significant difference in various groups (P > 0.05). Moreover, the CPS group showed a higher serum IL-4 (P < 0.05) but a lower IFN-gamma/IL-4 level as compared with those in the NP group (P < 0.01).

CONCLUSIONPhlegm, which is considered by Chinese medicine as an inveterate root of asthma, might be closely related with the inflammation in modern medicine. The inflammatory characteristics of asthma in patients with CPS partially present as increase of EOS, possibly show Th2 dominant trend, similar to that presented in eosinophilic asthma. Asthma with HPS embodies increase of NEU in respiratory tract. EOS and ECP might be the important markers for microcosmic syndrome differentiation of CPS, and NEU might be that for HPS.