Dynamic Toll-like receptor expression predicts outcome of sclerotherapy for lymphatic malformations with OK-432 in children

Abstract Background Sclerotherapy with OK-432 is recommended as a first-line treatment for lymphatic malformations. However, 40% of patients show poor response, defined by involution to Methods Blood was taken from children with low responder (LR, n = 6) and high responder (HR, n  = 5) of previous OK-432 treatment. Monocytes were stimulated with LPS for 20 h. TLR expression was analyzed with fluorescence-activated cell sorting (mean fluorescence intensity). The level of significance was P  ≤ 0.05. Results The mean age of patients in the HR group was 1.4 ± 0.9 y and in the LR group 2.8 ± 2.9 y ( P  = 0.31). The mean TLR4 upregulation after LPS stimulation in the HR group was significantly higher than in the LR group (factor 3.6 versus factor 1 compared with nonstimulated controls; P  = 0.037). The mean TLR7 expression did not show significant differences between the groups. Conclusions Dynamic TLR4 expression represents most probably a predictive parameter for the treatment of lymphatic malformations with OK-432 and should be further investigated.