Abstract: In the past decade, modifications in HCT management and supportive care have resulted in changes in recommendations for the prevention of infection in HCT patients. These changes are fuelled by new antimicrobial agents, increased knowledge of immune reconstitution, and expanded conditioning regimens and patient populations eligible for HCT. Despite these advances, infection is reported as the primary cause of death in 8% of autologous HCT patients and 17 – 20% of allogeneic HCT recipients . The major changes in this document, including changes in recommendation ratings, are summarized here.
The organization of this document is similar to the previous guidelines. Specifically, the prevention of exposure and disease among pediatric and adult autologous and allogeneic HCT recipients is discussed. The current recommendations consider myeloablative and reduced intensity conditioning for allogeneic HCT similarly since data on infectious complications following reduced intensity conditioning compared to myeloablative conditioning are sparse [4–7]. However, increased information regarding post-transplant immune recovery highlighting differences between myeloablative and reduced intensity HCT are included.
The sections of the document have been re-arranged in an attempt to follow the time course of potential infectious risks for patients receiving HCT. Following the background section, information on hematopoietic cell product safety is provided. The subsequent sections discuss prevention of infection by specific micro-organisms. Following organism-specific information, the sections then discuss means of preventing nosocomial infections as well as “do’s and don’ts” for patients following discharge post-transplant. Finally, information on vaccinations is provided. This will hopefully allow the reader to follow the prevention practices needed from the time a donor is selected until the patient regains immune competence.
Several topics are new or expanded from the prior document (Table 2). These include information on multiple organisms which were previously not discussed but have seemingly become more clinically relevant in HCT patients over the past decade. Data, and where possible, recommendations are provided regarding the following organisms that were not included in the previous document: Bordetella pertussis; the polyomaviruses BK and JC; hepatitis A, B, and C viruses; human herpesviruses 6, 7, and 8; human metapneumovirus; human immunodeficiency virus; tuberculosis; nocardiosis; malaria; and leishmaniasis. In recognition of our global society, several organisms are discussed that may be limited to certain regions of the world. Included in that section are also those infections that may be ubiquitous but occur infrequently, such as Pneumocystis jiroveci and Nocardia.
Summary of Changes compared to the Guidelines published in 2000 .
Several other changes should be noted. For bacterial infections, these guidelines now recommend quinolone prophylaxis for patients wth neutropenia expected to last as least 7 days (BI). Additionally, the recommendations for contact precautions (AIII), vaccination (BI), and prophylaxis patients with GVHD (AIII) against Streptococcus pneumoniae have been strengthened. The subsection on central line associated blood stream infections is now in the bacterial section. The vaccination section has been dramatically expanded. Changes include the recommendations for PCV rather than PPSV-23 for pneumococcal vaccination, starting some vaccinations earlier post-transplant, and the addition of recommendations for Varivax, HPV vaccine, and (the non-use of) Zostavax vaccine are included. Two additional appendices were added to provide information on desensitization to sulfa drugs and visitor screening questionnaires. Finally, the dosing appendix has merged both adult and pediatric dosing and provides recommendations for several newer antimicrobial agents that were not previously available.
In summary, the changes and expansion to this document reflect the growing body of literature detailing infectious complications in HCT patients.