[Bronchiolitis obliterans with severe obstructive ventilation disorder after a bone marrow transplant. Study of 7 cases].

In 40 to 60% of bone marrow grafts there are pulmonary complications of which the most frequent is the occurrence of an interstitial pneumonia. We report 7 cases here of a more rare complication, that of bronchiolitis obliterans (BO). Between December 1979 and November 1989, 7 patients (3.4% of our cases of GMO) have developed over several months a chronic obstructive respiratory failure (a mean VEMS of 43% of the theoretical value) in the year following the transplantation (mean delay 190 days). 6 patients presented with cutaneous, digestive or hepatic signs of chronic graft v host illness (GVH) whereas the prevalence of this complication in the population studied was 17%. Treatment combining bronchodilators and immunosuppressants was only successful in 2 cases and the outcome was fatal in the 5 other cases as a result of respiratory failure (mean delay 208 days between the appearance of respiratory symptoms and death). The pathogenesis of BO after GMO remains poorly understood. It may rest on an immune process during the course of which the BO would be the result of a chronic pulmonary GVH. Another hypothesis is that the state of the immunosuppression in these patients would favour the appearance of a bronchiolitis of an infectious origin, particularly viral. The prognosis of BO after GMO is very poor and in the absence of specific effective treatment the therapeutic strategy remains essentially that of prevention by the early detection of respiratory anomalies.