Pre-transplant soluble CD30 level as a predictor of not only acute rejection and graft loss but pneumonia in renal transplant recipients

Pre-transplant sera of 586 renal graft recipients were tested to investigate whether soluble CD30 (sCD30) is a useful predictor of some severe clinical episodes post-transplant. Correlation analysis showed sCD30 level was significantly correlated with acute rejection (AR) (r = 0.242, P < 0.001), graft loss (r = 0.162, P < 0.001), and pneumonia (r = − 0.147, P < 0.001). Higher sCD30 levels were observed in patients with AR than the others (180.0 ± 89.1 vs. 135.3 ± 72.7 U/ml, P < 0.001). And patients with pneumonia had significantly lower pre-transplant sCD30 level than the others (123.2 ± 75.5 vs. 150.7 ± 79.6 U/ml, P = 0.003). Based on statistical results, 120 and 240 U/ml were selected as the optimal couple of cut-off value to divide patients into three groups: Group High (H), Group Intermedial (I) and Group Low (L). The lowest AR rate of 17.4% was observed in Group L (P < 0.001). Significant difference of AR rate was also observed between Group I (29.2%) and H (42.9%) (P < 0.001). There were much more patients suffering pneumonia in Group L (P = 0.001). Significantly lower 5-year patient survival rate (79.4%) was observed in Group H (P = 0.016). These data showed that elevated pre-transplant sCD30 level of renal allograft recipients may reflect an immune state detrimental for renal allograft survival. But sCD30 level lower than < 120 U/ml may be associated with a high risk of pneumonia. Pre-transplant sCD30 level is an independent predictor of acute rejection, lung infection, even graft survival. Suitable immunosuppression protocol should be selected according to pre-transplant sCD30 level in an attempt to promote patient and graft survival.