Assessment of macrophages of the residual spleen after subtotal splenectomy for splenomegaly

Objective To investigate the distribution and the content of macrophages (mΦ) in the residual splenic tissue after subtotal splenectomy.Methods Thirteen patients with splenomegaly due to portal hypertension were studied.The specimens were obtained by operation or puncture biopsy.There were 2 groups:the splenomegaly and the residual spleen groups.The control group consisted of 13 patients with trauma-induced splenic rupture.The samples were sliced,and the distribution and counts of mΦ were observed under light microscopy using immunohematological staining.Results The mΦ of the residual spleen were equally distributed in the splenic cord and they adhered to the wall of the splenic sinus in the red pulp.They had a high density and were deeply stained.In the white pulp,the mΦ were scattered in the splenic corpuscle and were significantly concentrated in the marginal zone (MZ),where larger mΦ were found.There was a significantly higher number of mΦ in the red pulp of the residual spleen group when compared with the splenomegaly and the control groups.There was a significantly higher number of mΦ in the red pulp of the control group (7.46±0.86) when com pared with the splenomegaly group (4.20±0.88) or with the residual spleen group (31.09±9.73).A significant difference was not observed among the three groups in the white pulp (splenic corpuscle and MZ).Conclusions After subtotal splenectomy for splenomegaly due to portal hypertension,the number of unit area of mΦ in the red pulp in the residual spleen increased significantly,while the number of mΦ in the white pulp did not change much in the three groups of patients.The results suggested that residual spleens still have good phagotrophic functions. Key words: Spleen;  Hypersplenism;  Macrophages;  Hypertension, portal