Advances in TransplantationStem cell transplantationInfectious Complications and Multidrug-Resistant Bacteria in Patients With Hematopoietic Stem Cell Transplantation in the First 12 Months After Transplant

- Infections in hematopoietic stem cell transplant occur in about 50% of cases during the first year.
- Pneumonia, bloodstream infection, and urinary tract infections are the most frequent infections.
- Multidrug-resistant bacteria (MDRB) are reported in one-third of all infections.
- Multidrug-resistant bacteria (MDRB) infections were associated with higher mortality rates in allogeneic transplant recipients.
- Pneumonia episodes were associated with 12-month mortality rates.

BackgroundHematopoietic stem cell transplantation (HSCT) has been used as treatment in different hematologic and solid malignancies. The aim of this study was to describe the frequency of infectious complications, microbiology, and outcome in patients undergoing HSCT in Mexico during the pre-engraftment period and the impact on mortality rates at 12 months.MethodsWe conducted a retrospective study of all hematologic malignancies that received HSCT from January 2009 and December 2014, at an oncology reference center.ResultsWe included 210 patients: 144 autologous (69%) and 66 allogeneic HSCT (31%). There were 184 infections documented in 109 patients; incidence rate was 47.2 per 1000 neutropenia/days and 22.4 per 1000 hospitalization/days. The main infections reported were pneumonia (n = 40, 19%), bloodstream infections (n = 36, 17.1%), and central line-associated bloodstream infections (n = 28, 13.3%). There were 110 bacteria isolated, 31 were multidrug-resistant (26 were extended-spectrum beta-lactamase; Escherichia coli). There were 25 disseminated or complicated viral infections and 20 invasive fungal diseases. Fourteen patients died in the first 30 days (all related to the infectious process). In multivariate analysis leukemia, more than 2 chemotherapy regimens before transplant and pneumonia were related to 12-month mortality rates.ConclusionsEven though infectious processes are frequent in patients with HSCT, multidrug-resistant bacteria were not as frequent as supposed; however, when these microorganisms are involved, mortality rate is increased. It is important to be alert that patients with pneumonia have a significantly increased mortality risk in the first year.