Incidence of Sinusoidal Obstruction Syndrome/Veno-Occlusive Disease and Treatment with Defibrotide in Allogeneic Transplantation: A Multicenter Australasian Registry Study.

Sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) is an established complication in patients undergoing allogeneic hemopoietic stem cell transplantation (HSCT). Defibrotide is an effective and safe pharmacologic option for treating diagnosed SOS/VOD. By exploring data provided to the Australasian Bone Marrow Transplant Recipient Registry (ABMTRR) by centers in Australia and New Zealand, this study aimed to describe the incidence of SOS/VOD and patterns of defibrotide use from 2016 to 2020. Patients who underwent allogeneic hemopoietic stem cell transplantation between 2016 and 2020 were identified from the ABMTRR. Data were extracted for a total of 3346 patients, 2692 from adult centers and 654 from pediatric centers, with a median follow-up of 21.5 months and 33.3 months, respectively. Descriptive statistics were used to describe the patient population, including the incidence of SOS/VOD and defibrotide use. Comparisons were made between patients without SOS/VOD and those with SOS/VOD, divided into defibrotide and no defibrotide cohorts. Associations with overall survival (OS) and day 100 survival with such variables as sex, age, disease at transplantation, stem cell source, conditioning agents, SOS/VOD diagnosis, and use of defibrotide, were determined. The reported incidence of SOS/VOD was 4.1% in adult centers and 11.5% in pediatric centers. Defibrotide was administered to 74.8% of adult patients and 97.3% of pediatric patients with SOS/VOD. Significant variability in the use, dosage, and duration of defibrotide was seen across the adult centers. The day 100 survival rate and median OS for patients managed with defibrotide was 51.8% and 103 days, respectively, for adult patients and 90.4% and not reached, respectively, for pediatric patients. In adults, older age at transplantation, an HLA-matched nonsibling relative donor, and a diagnosis of SOS/VOD treated with defibrotide were associated with reduced OS. In pediatric patients, the patient and transplantation characteristics associated with reduced OS were a diagnosis of SOS/VOD and a ≥2 HLA-mismatched related donor. A collaborative approach across Australasia to diagnosing and managing SOS/VOD, particularly with respect to consistent defibrotide use, is recommended.

Dual Hip DXA. Is it Time to Change Standard Protocol?

Previous studies have examined the utility of bilateral DXA hip bone mineral density (BMD) scans. While most studies demonstrate an advantage of bilateral hip scanning, the studies have been limited by size, or have not included simultaneous lumbar spine scans. To analyse the utility of dual hip scans in a clinical environment, a large retrospective study was performed of DXA BMD of both hips, and lumbar spine, in 17,169 individuals assessed at one centre over 10 years. There was no clinically significant difference in the population mean femoral neck BMD of the left vs the right leg (0.878 vs 0.881g/cm2) or total proximal femoral BMD of the left vs the right leg (0.920 vs 0.919g/cm2). There were however discrepancies in individuals between hip t-scores. For the total hip 1,977 (11.5 %) and 147 (0.9 %) of subjects had absolute t score differences ≥ 0.50 or ≥ 1.00. respectively. For the femoral neck 3,320 (19.3%) and 337 (2.0%) of subjects had absolute t score differences ≥ 0.50 or ≥ 1.00. respectively. Of the total 17,169 individuals there were 2,776 subjects with osteoporosis (T≤ -2.5) using the lumbar spine and right hip, compared to 2,834 subjects using the lumbar spine and left hip. Using the lumbar spine and both hips identified 3,214 individuals with osteoporosis. Diagnosis based on use of the lumbar spine and right hip BMD, or lumbar spine and left hip BMD, therefore failed to identify 15.8%, or 13.4%, of osteoporotic subjects respectively. Additional scanning time required was assessed in 40 subjects prospectively. Performing lumbar spine and both hips, compared to lumbar spine and one hip, required an average additional scan time of 55 seconds. The recommendation of best practise for DXA BMD measurements should be reviewed to consider lumbar spine and dual hip DXA as standard of care.