Chronic airflow obstruction in long-term survivors of allogeneic bone marrow transplantation

Prospective pulmonary function tests (PFTs) of 49 long-term survivors of identical sibling bone marrow transplants (BMT) were analysed. Eight (16%) developed a persistent pulmonary syndrome characterised by a late onset, cough and dyspnoea, hyperinflation or patchy infiltrates on plain radiography and episodic bacterial infections. The predominant PFT pattern was obstructive (reduced forced expiratory ratio, FER) with a variable restrictive component (reduced vital capacity, VC). When compared with the other 41 patients (controls), mean FER (53% absolute) and VC (73% predicted) were significantly lower at 12 months (P = 0.005). Graft-versus-host disease (GVHD) was the only identifiable risk factor (odds ration 7.1). Five of 7 patients compared with 4 of 31 controls tested at 3 months had an abnormal FER or maximum mid-expiratory flow rate (MMFR), but not VC, prior to the onset of symptoms (P = 0.015). Patients with mild to moderate disease (FER 50-70%) had stable pulmonary function while severe cases progressed despite immunosuppressive agents. Earlier recognition of this syndrome by a reduced FER or MMFR may allow the initiation of therapy at a potentially reversible stage.