Spleen sizing by ultrasound scan and risk of pneumococcal infection in patients with chronic GVHD: preliminary observations.

Encapsulated bacteria infections (EBI) can cause severe complications after BMT, usually occurring in patients with chronic GVHD (cGVHD) and attributed to functional hyposplenism. Using ultrasound (US) scan, we measured spleen size in 22 patients transplanted from HLA identical siblings, with or without cGVHD. No patient had received TBI, spleen irradiation or penicillin prophylaxis. Results were correlated with occurrence of EBI during a mean follow-up of 55 months (range 7-93). In the group without cGVHD, the difference between pre- and post-BMT spleen longitudinal diameters was not significant, and no patient developed EBI. In the cGVHD group, post-BMT spleen longitudinal diameters were significantly smaller than those pre-BMT (9.1+/-1.6 vs. 12.3+/-2.2; P = 0.0005). Out of four patients with cGVHD who showed a major spleen size reduction, two developed a severe infection (an overwhelming sepsis and a pneumococcal meningitis). In our small series, we found a borderline relationship between spleen size reduction and duration of cGVHD (P = 0.06), as well as an increased risk of life-threatening infection in patients with extensive cGVHD and hyposplenism as detected by US scan. We conclude that US scan may be useful to detect spleen size reduction following allogeneic BMT and that penicillin prophylaxis is to be strongly recommended in patients with extensive cGVHD and spleen size reduction, even in those who have not received total body or spleen irradiation.