Bronchiolitis obliterans in bone marrow transplantation and its relationship to chronic graft-v-host disease and low serum IgG.

The records of 549 bone marrow transplant (BMT) patients at The Johns Hopkins Oncology Center during a 9-year period were reviewed to determine the incidence of bronchiolitis obliterans (BrOb). Seven patients had BrOb. All seven died, and BrOb was a contributing cause of death in six patients. Only recipients of allogeneic BMT were at risk for developing BrOb (2% incidence). Three cases were incidentally discovered at autopsy in patients who died less than 120 days after BMT from ventilatory failure owing to interstitial pneumonitis. Four cases were patients who died greater than 120 days after BMT. Of this latter group, all had overt chronic graft-v-host disease (CGVHD). Among 120 day survivors of allogeneic BMT, 6% of those with CGVHD developed BrOb as compared with none of those without CGVHD (P = .008). Five percent of patients with reduced IgG levels at day 120 developed BrOb as compared with none of those with normal IgG (P = .04). The incidence of BrOb in 120-day survivors was 14% (4 of 29) in patients with both CGVHD and decreased serum IgG, whereas patients with CGVHD only (0 of 25), those with decreased IgG levels only (0 of 53), and those with no CGVHD and normal IgG levels (0 of 70) did not develop BrOb.