The acute impact of a hematopoietic allograft on lung function and inflammation: a prospective observational study

No studies have investigated the immediate impact of receiving an allogeneic hematopoietic stem cell transplant (HSCT) on pulmonary inflammation or lung function.

Using a prospective study design, we quantified the changes in these outcome measures in eligible adult individuals in the first six months after receiving an allogeneic hematopoietic stem cell transplant.

Between January 2007 and December 2008, 72 patients were eligible to participate in the cohort, and of these 68 (94%) were included in the study. Compared to baseline, pulmonary inflammation as measured by exhaled nitric oxide increased after receiving a HSCT with the largest increment seen at three months (+6.0 ppb, 95%CI: +0.4 to +11.5), and this was sustained at six months. Percent predicted forced expiratory volume in one second decreased over the same period, with the largest decrease observed at six weeks (-5.9%, 95% CI: -8.9 to -2.9), and this was also sustained over a six month period. Similar associations were observed for FVC. A larger increase in exhaled nitric oxide from baseline at six weeks and three months may be associated with decreased mortality (p=0.06, p=0.04 respectively).

Our data demonstrate that recipients of an allogeneic HSCT experience an increase in biomarkers of pulmonary inflammation and a decrease in lung function in the first six months after the procedure. If independently validated in other study populations, these observations could have potential as a prognostic biomarker for this patient group.