[Obstructive lung disease after allogenic stem cell transplantation in children].

Introduction: Bronchiolitis obliterans is recognized as a life-threatening pulmonary complication that can develop 3 months after bone marrow transplantation.
Objective: To determine the incidence and clinical progression of obstructive lung disease (OLD) in a population of children who had undergone allogenic hematopoietic stem cell transplantation (HSCT).
Patients and Methods: We examined a sequential sample of 110 patients who received allogeneic HSCT between January 1992 and June 2002. The incidence of OLD in the 77 children who survived for more than 100 days after transplantation was analyzed. The diagnosis of OLD was based on clinical findings with no evidence of infection, pulmonary function test (FEV1/FVC less than 80 % and FEV1 less than 80 % of predicted value) and computed tomography scan.
Results: Eight patients (10.4 %) developed OLD at a median time of onset of 184 days after allogenic HSCT (range: 100-1735 days). All patients with OLD had respiratory symptoms. In six out of eight patients airflow obstruction was diagnosed within 1 year of transplantation. All patients showed chronic graft-versus-host disease (GVHD) (p < 0.01). The incidence of OLD in the 23 patients with chronic GVHD was 34.8 %. Two patients (25 %) had a complete response to intensified treatment of chronic GVHD with immunosuppressant therapy. FEV1 declined rapidly in three patients (37.5 %) who died of respiratory failure. Two patients (25 %) had partial reversal but pulmonary function continued below normal values. In one patient (12.5 %) severe obstructive disease was stable.
Conclusions: The time of onset and form of progression of OLD after HSCT may vary. OLD is strongly associated with chronic GVHD and its incidence depends on the number of patients with chronic GVHD.