Monitoring of early humoral immunity to identify lung recipients at risk for development of serious infections: A multicenter prospective study.

BACKGROUND: Infection is still a leading cause of death during the first year after lung transplantation. We performed a multicenter study among teaching hospitals to assess monitoring of early humoral immunity as a means of identifying lung recipients at risk of serious infections. METHODS: We prospectively analyzed 82 adult lung recipients at 5 centers in Spain. Data were collected before transplantation and at 7 and 30 days after transplantation. Biomarkers included IgG, IgM, IgA, complement factors C3 and C4, titers of antibodies to pneumococcal polysaccharide antigens (IgG, IgA, IgM) and antibodies to cytomegalovirus (IgG), and serum B-cell activating factor (BAFF) levels. The clinical follow-up period lasted 6 months. Clinical outcomes were bacterial infections requiring intravenous anti-microbial agents, cytomegalovirus (CMV) disease, and fungal infections requiring therapy. RESULTS: We found that 33 patients (40.2%) developed at least 1 serious bacterial infection, 8 patients (9.8%) had CMV disease, and 10 patients (12.2%) had fungal infections. Lower IgM antibody levels against pneumococcal polysaccharide antigens at Day 7 (defined as <5 mg/dl) were a risk factor for serious bacterial infection (adjusted odds ratio [OR] 3.96; 95% confidence interval [CI] 1.39 to 11.26; p = 0.0099). At Day 7 after transplantation, IgG hypogammaglobulinemia (defined as IgG <600 mg/dl) was associated with a higher risk of CMV disease (after adjustment for CMV mismatch: OR 8.15; 95% CI 1.27 to 52.55; p = 0.028) and fungal infection (adjusted OR 8.03, 95% CI 1.51 to 42.72; p = 0.015). Higher BAFF levels before transplantation were associated with a higher rate of development of serious bacterial infection and acute cellular rejection. CONCLUSION: Early monitoring of specific humoral immunity parameters proved useful for the identification of lung recipients who are at risk of serious infections.

Prophylaxis with nebulized liposomal amphotericin B for Aspergillus infection in lung transplant patients does not cause changes in the lipid content of pulmonary surfactant.

BACKGROUND: Prophylaxis with inhaled liposomal amphotericin B has proven to be safe and effective for preventing infection due to Aspergillus spp in lung transplant recipients. However, the liposome contains a large quantity of phospholipids, and inhalation of these substances could potentially change the composition of pulmonary surfactant. The aim of this study was to determine the lipid composition of pulmonary surfactant in patients receiving inhaled liposomal amphotericin B prophylaxis. METHODS: A prospective, open, controlled multicenter study was conducted in 2 groups: 19 lung transplant recipients who received regular prophylaxis with inhaled amphotericin B (study group) and 19 recipients who did not receive inhaled prophylaxis (control group). From both groups, 15 ml of the third aliquot of bronchoalveolar lavage fluid was obtained and phospholipid content determined in the active fraction of surfactant (large aggregates) and in the inactive fraction (small aggregates). Large aggregate cholesterol content was also determined. RESULTS: Patient demographic data and characteristics were similar in the 2 groups. No between-group differences in median phospholipid content were found for large aggregates (study group, 0.4 [range, 0.18-1.9] µmol vs controls, 0.36 [range 2.15-0.12] µmol; p = 0.69) or small aggregates (study group, 0.23 [range, 0.1-0.58] µmol vs controls, 0.29 [range, 0.18-0.65] µmol; p = 0.33). The small aggregate-to-large aggregate phospholipid ratio, commonly used as a marker of alveolar injury, showed no differences between the groups (study group, 0.56 vs controls, 0.69; p = 0.28). Nor were there differences in the cholesterol content of large aggregates (study group, 0.04 µmol [range 0.01-0.1] vs controls, 0.04 µmol [range 0.02-0.27); p = 0.13). CONCLUSIONS: These results seem to indicate that prophylaxis with nebulized liposomal amphotericin B does not cause changes in the lipid content of pulmonary surfactant.