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Summary Adenovirus (AdV) infections are a frequent cause of morbidity and mortality following allogeneic stem cell transplantation (SCT), and disseminated infection is associated with high mortality, particularly in paediatric SCT. Here, we describe an approach to reduce mortality from adenoviraemia by combining prospective monitoring for the occurrence of adenoviraemia using a sensitive polymerase chain reaction method, early antiviral therapy and prompt withdrawal of immunosuppression. A total of 155 consecutive paediatric SCT procedures were prospectively monitored, of which 113 (73%) transplants involved donors other than matched siblings and 126 (83%) employed T‐cell depletion. Adenoviraemia was detected in 26/155 (17%) transplants and developed exclusively in patients who had received T‐cell‐depleted grafts. Withdrawal of immunosuppression coupled with early antiviral therapy led to resolution of adenoviraemia in 19/26 (81%) patients with only five patients succumbing to disseminate AdV infection. Survival from adenoviraemia was associated with lymphocyte recovery to above 0·3 × 109/l. Mortality was closely linked with the absence of lymphocyte recovery because of profound T‐cell depletion of the graft with CD34+ magnetic‐activated cell sorting. Mortality from disseminated AdV infection was 5/26 (19%) in this study, which is significantly lower than previously reported.

Deficiency of the purine salvage enzyme adenosine deaminase leads to SCID (ADA-SCID). Hematopoietic cell transplantation (HCT) can lead to a permanent cure of SCID; however, little data are available on outcome of HCT for ADA-SCID in particular. In this multicenter retrospective study, we analyzed outcome of HCT in 106 patients with ADA-SCID who received a total of 119 transplants. HCT from matched sibling and family donors (MSDs, MFDs) had significantly better overall survival (86% and 81%) in comparison with HCT from matched unrelated (66%; P < .05) and haploidentical donors (43%; P < .001). Superior overall survival was also seen in patients who received unconditioned transplants in comparison with myeloablative procedures (81% vs 54%; P < .003), although in unconditioned haploidentical donor HCT, nonengraftment was a major problem. Long-term immune recovery showed that regardless of transplant type, overall T-cell numbers were similar, although a faster rate of T-cell recovery was observed after MSD/MFD HCT. Humoral immunity and donor B-cell engraftment was achieved in nearly all evaluable surviving patients and was seen even after unconditioned HCT. These data detail for the first time the outcomes of HCT for ADA-SCID and show that, if patients survive HCT, long-term cellular and humoral immune recovery is achieved. (Blood. 2012;120(17):3615-3624)

Background Patients with severe combined immunodeficiency disease (SCID) who have matched sibling donors (MSD) can proceed to hematopoietic cell transplantation (HCT) without conditioning chemotherapy. Objective To determine whether the results of HCT without chemotherapy-based conditioning from matched unrelated donors (URD), either from volunteer adults or umbilical cord blood, are comparable to those from matched sibling donors (MSD). Methods A multicenter survey of SCID transplant centers in North America, Europe, and Australia to compile retrospective data on patients who have undergone unconditioned HCT, from either URDs (n = 37) or MSDs (n = 66). Results Most patients undergoing URD HCT (92%) achieved donor T-cell engraftment, compared to 97% for MSDs, however, estimated 5-year overall and event-free survival were worse for URD recipients (71% and 60%, respectively), compared to MSD recipients (92% and 89%, respectively; P <0.01 for both). URD recipients who received pre-HCT serotherapy had similar 5-year OS (100%) to MSD recipients. The incidences of Grade II-IV acute and chronic GVHD were higher in URD (50% and 39%, respectively), compared to MSD recipients (22% and 5%, respectively; P <0.01 for both). In the surviving patients, there was no difference in T-cell reconstitution at last follow-up between the URD recipients and MSD recipients, however MSD recipients were more likely to achieve B-cell reconstitution (72% vs. 17%; P <0.001). Conclusion Unconditioned URD HCT achieves excellent rates of donor T-cell engraftment similar to MSD recipients, and reconstitution rates are adequate. However, only a minority will develop myeloid and B cell reconstitution and attention must be paid to GVHD prophylaxis. This approach may be safer in children ineligible for intense regimens to spare potential complications of chemotherapy.

Genomics has the potential to revolutionize medical approaches to disease prevention, diagnosis, and treatment, but it does not come without challenges. The success of a national population-based genome program, like the Qatar Genome Program (QGP), depends on the willingness of citizens to donate samples and take up genomic testing services. This study explores public attitudes of the Qatari population toward genetic testing and toward participating in the QGP. A representative sample of 837 adult Qataris was surveyed in May 2016. Approximately 71% of respondents surveyed reported that they were willing to participate in the activities of the QGP. Willingness to participate was significantly associated with basic literacy in genetics, a family history of genetic diseases, and previous experience with genetic testing through premarital screening. Respondents cited the desire to know more about their health status as the principle motivation for participating, while lack of time and information were reported as the most important barriers. With QGP plans to ramp up the scale of its national operation toward more integration into clinical care settings, it is critical to understand public attitudes and their determinants. The results demonstrate public support but also identify the need for more education and individual counseling that not only provide information on the process, challenges, and benefits of genomic testing, but that also address concerns about information security.