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Infections caused by Stenotrophomonas maltophilia (SM) have documented high mortality rate in immunocompromised patients.This nationwide multicenter study was performed to analyze the epidemiology of SM infections in children undergoing anticancer therapy (pediatric hematology and oncology [PHO]) or hematopoietic cell transplantation (HCT) over 2012-2019, including incidence and outcome of SM infections, as well as treatment regimens and multidrug resistance.Cumulative incidence of SM infections was calculated using the competing risk analysis from the day of diagnosis (PHO setting) or from the day of transplantation (HCT setting). The Kaplan-Meier method was used to determine survival from infection.During the study period of 8 years, a total number of 1356 HCTs and 7337 children newly diagnosed for malignancy were analyzed. Diagnosis of acute leukemia was a predisposing factor for SM infection. The cumulative incidence of SM infections was comparable in HCT patients in comparison to PHO (0.81% vs. 0.76%). High rate of trimethoprim/sulfamethoxazole susceptibility among SM isolates was observed in both groups of patients (80.8%). Although this was the drug of choice, survival rates from SM infections were significantly lower in HCT than in PHO (45% vs. 85%, P = 0.001, log-rank test). We found the transplant procedure and lack of clinical resolution after 18 days of antibiotic therapy to be independent mortality risk factors.The risk of SM infections and the occurrence of resistant bacterial strains in allo-HCT patients were comparable to PHO patients. Irrespective of target antibiotic therapy, the outcome of SM infections was better in the PHO setting.

Additional file 1. List of chemotherapy protocols.

Medium modifications of the pion-omega-rho vertex are analyzed in context of the omega -> pi gamma* and rho -> pi gamma* decays in nuclear matter. A relativistic hadronic model with mesons, nucleons, and Delta(1232)isobars is applied. A substantial increase of the widths for the decays omega -> pi gamma* and rho -> pi gamma* is found for photon virtualities in the range 0.3-0.6 GeV. This enhancement has a direct importance for the description of dilepton yields obtained in relativistic heavy-ion collisions., 6 pages, to appear in Proc. 2nd International Symposium on Quantum Theory and Symmetries, Cracow, 18-21 July 2001

We calculate the medium modification of the pi-omega-rho vertex and analyze its significance for the pi^0 -> gamma gamma*, omega -> pi^0 gamma*, and rho -> pi gamma* decays in nuclear matter. We use a relativistic hadronic approach at zero temperature and in the leading-density limit, and consider decays of particles at rest with respect to the medium. It is shown that for the pi^0 -> gamma gamma* the effects of the Delta isobar cancel almost exactly the effects of the nucleon ph excitations, such that the net medium effect is small. On the contrary, for the decays omega -> pi^0 gamma* and rho -> pi gamma* we find a sizeable increase of the partial widths at virtualities of the photon in the range 0.3-0.6 GeV. The effect has direct significance for the calculation of dilepton yields from the Dalitz decays in relativistic heavy-ion collisions., 9 pages, 3 figures