DISCREPANCY OF CLINICAL, RADIOGRAPHIC AND HISTOPATHOLOGIC FINDINGS IN2 CHILDREN WITH CHRONIC PULMONARY GRAFT-VERSUS-HOST DISEASE AFTER HLA-IDENTICAL SIBLING STEM-CELL TRANSPLANTATION

We report two children who presented with cough and shortness of breat h 7-8 months after a matched sibling stem cell transplant (SCT) for ch ronic myelogenous leukemia and myelodysplastic syndrome, respectively, Pulmonary function tests (PFTs) revealed severe airways obstruction ( AO), However, radiographic investigations showed no serious abnormalit ies in the early phase and open lung biopsy revealed only mild lymphoc ytic bronchiolitis and bronchiolitis obliterans consistent with pulmon ary graft-versus-host disease (GVHD), Despite administration of bronch odilators and various immunosuppressive agents obstructive lung diseas e progressed to pulmonary failure in patient 1, whereas stabilization of the clinical course was observed in patient 2, Serial PFTs were the best predictor of the clinical course in contrast to radiographic and histologic findings. It is concluded that PFTs should be performed re peatedly in pediatric patients after allogeneic SCT with the aim of di agnosing GVHD-associated AO in the subclinical phase, Progressive post -transplant AO necessitates prompt initiation of intensive immunosuppr essive therapy in order to stop the underlying immunopathologic proces s even in the absence of severe radiographic and histologic findings.