OBJECTIVETo explore and compare the clinical effects of three immuno-potentiators and their influence on immune function in preventing and treating recurrent respiratory tract infection (RRI).

METHODSSeventy-two children with RRT were assigned to three groups, the 23 patients in the M group treated with milkvetch extract oral liquid, the 23 in the P group treated by P-transfer factor and the 26 in the U group treated by Utilins injection. Clinical effect was compared among three groups after treatment, and changes of T cell subgroups as well as immune antibodies were detected before and after treatment.

RESULTSThe markedly effective rate in the M, P, and U group was 69.6%, 65.2%, and 73.0% respectively, and the total effective rate 87.0%, 82.6%, and 92.3%, showing an insignificant difference among them (all P>0.05). After treatment, the levels of CD3+, CD4+ and CD4+/CD8+ rose obviously in the three groups (all P<0.05); levels of CD8+ in the M group and the P group lowered significantly (P<0.05, P<0.01), but with no significant difference among three groups in the changes of T cell subgroups (all P>0.05). Serum levels of IgG in all the three groups, IgA in the P group and the M group, and IgM in the M group and the U group rose significantly (P<0.05 or P<0.01), with statistical difference presented in comparing of IgA level in the P group with that in the other two groups (P<0.01).

CONCLUSIONThe clinical effects and the outcomes of immunological indexes' changing are similar in RRI patients treated by the three immuno-potentiators. They all can enhance the immunological function of the organism, strengthen the disease-resistant ability of patients, and reduce the incidence of RRI. Among them, the milkvetch extract oral liquid is worthy of spreading due to its lower cost, simple administration, exemption from painful injection, and good compliance.