Birgitta Versluijs

136 Patients and methods ced intensity conditioning, omitting or reducing the dose of busulfan (AUC 60 mg*h/l in 3 days). In patients receiving an unrelated donor transplant serotherapy was given with antithymocyte globuline (ATG; thymoglobuline). During the time of this study the dosing schedule of ATG has changed. Until June 2009 ATG was administered until day -1, from June 2009 onwards it was given earlier, from day -9 until day - 6. In patients with very high risk malignancies (relapsed myeloid leukemia, early relapsed lymphoid leuke- mia) receiving a cord blood (CB) donor we omitted ATG from December 2012 onwards. Standard GvHD prophylaxis consisted of cyclosporine (aiming for a through level of 150-250 μg/l). In CB transplant prednisolone (1 mg/kg/day for 28 days, taper in 2 weeks) was added. Patients receiving an unrelated bone marrow (BM) transplant methotrexate (short course, 10 mg/m 2 on day 1,3,6) was given. From 2013 we also gave short course methotrexate to the older patients (>12 yr) receiving bone marrow from an HLA matched sibling. Antimicrobial screening and prophylaxis Antimicrobial prophylaxis consisted of daily ciprofloxacin and fluconazole, from the start of conditioning until the resolution of neutropenia. Additional prophylaxis against Strep- tococcus viridans was given with cefazoline in the mucositis phase. Pneumocystis jirovecii pneumonia prohylaxis was started from 1 month after transplantation as cotrimoxazole 3 times a week. In case of positive serology for herpes simplex virus in all patients, and in case of positive serology for varicella zoster virus in cord blood transplant recipients, prophylaxis with aciclovir was given until immune-recovery (CD4+ > 200/uL). Patients regarded high risk for invasive fungal infection (IFI) received Aspergillus prophylaxis with either daily voriconazol or twice weekly amfothericine B. Stools and nose/throat swabs were cultured weekly, for bacterial colonization and results guided empiric anti- biotic treatment in case of neutropenic fever. Plasma was tested weekly for Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpes-6 virus (HHV-6) and adenovirus (AdV) DNA positivity by real time PCR. Weekly galactomannan (Platelia Aspergillus en- zyme immunoassay; Bio-Rad, Hercules, CA) testing was performed to screen for Asper- gillus infection. From 2008, all patients were screened according to our pre-HCT pulmonary screening protocol as described before: 9 this includes microbial testing (bacterial cultures, PCR for Respiratory Virus (RV) panel, fungal cultures and Aspergillus antigen testing) in Bron- cho Alveolar Lavage (BAL) and NasoPharyngealAspirate (NPA), High Resolution Com- puted Tomography (HRCT) of the lungs and Pulmonary Function Tests (PFT) in child- ren over 5 years of age. Based on screening results, patients at high risk for developing Allo-LS (i.e. RV positive before HCT) received prolonged GvHD prophylaxis, as we have shown a protective effect of immunosuppressive therapy on the incidence of Allo-LS in RV positive patients. 4,8 8