Effect of maintenance azithromycin on established bronchiolitis obliterans syndrome in lung transplant patients

BACKGROUND:

Bronchiolitis obliterans syndrome (BOS), the main cause of late mortality following lung transplantation, is defined as an irreversible decline in forced expiratory volume in 1 s (FEV₁).Previous studies using azithromycin for BOS in lung transplant patients have demonstrated a potential reversibility of the decline in FEV₁.

OBJECTIVES:

To examine whether initiating azithromycin reverses decline in FEV₁ in lung transplant recipients with established BOS of at least three months.

METHODS:

Pulmonary function tests were performed every three months in seven lung transplant recipients with established BOS of at least three months. FEV₁ was recorded at six and three months before initiation, at time of initiation, and three, six, nine and 12 months postazithromycin initiation. The primary end point was change in FEV₁. During the study, no immunosuppressive medication changes or acute rejection episodes occurred.

RESULTS:

Mean time from transplant to azithromycin initiation was 64 months (range 17 to 117 months). Mean time from BOS diagnosis to azithromycin initiation was 22 months (range three to 67 months). Rate of FEV₁ decline from six months before azithromycin initiation, and rates of FEV₁ increase from initiation to three and 12 months post-treatment initiation, were not statistically significant (P=0.32, P=0.16 and P=0.18, respectively). Following a trend toward improvement in the first three months after treatment initiation, FEV₁ tended to stabilize.

DISCUSSION:

Although several studies address the possible benefit of maintenance azithromycin in lung transplant patients with BOS, the role of the drug remains unproven in these patients, and would best be addressed by a large randomized controlled trial.