Coexisting or underlying risk factors of hepatic veno-occlusive disease in pediatric hematopoietic stem cell transplant recipients receiving prophylaxis

Risk Factors for Sinusoidal Obstruction Syndrome After Hematopoietic Stem Cell Transplantation in Children and Young Adults: A Systematic Review and Meta-Analysis

OBJECTIVE AND BACKGROUND

Sinusoidal obstruction syndrome (SOS) is a life-threatening complication in hematopoietic stem cell transplantation (HSCT) patients. However, the related risk factors in pediatric and young adult HSCT recipients remain unclear. Thus, we conducted this meta-analysis to identify potential risk factors for SOS in children and young adults undergoing HSCT.

METHOD

We acquired related articles through searching PubMed, EMBASE, and the Cochrane Library up to May 31, 2024. We calculated odds ratios (ORs) and corresponding 95% confidence intervals (CIs) to identify potential risk factors.

RESULTS

A total of 12 studies with 7644 HSCT recipients were included. Bone marrow transplantation (OR = 1.35, 95% CI: 1.03-1.77, I2 = 0%), busulfan (BU) (OR = 3.63, 95% CI: 1.78-7.38, I2 = 70%), and fludarabine (FLU) (OR = 1.55, 95% CI: 1.09-2.21, I2 = 16%) were risk factors for SOS after HSCT in children and young adults.

CONCLUSION

Bone marrow transplantation and the use of BU or FLU might be risk factors for SOS after HSCT in children and young adults.

The outcome and complications of total parenteral nutrition in pediatric hematopoietic stem cell transplantation

BACKGROUND

Nutritional support posthematopoietic stem cell transplantation (HSCT) with total parenteral nutrition (TPN) or nasogastric tube feeding (NGT) in pediatric patients is associated with benefits and risks.

METHODS

We retrospectively reviewed the indication of TPN use in our pediatric HSCT patients and its impact on survival and possible related complications.

RESULTS

A total of 228 HSCTs were performed during the study period. TPN was used in 144 patients (63.2%) for a median of 14 days, while 8.8% had NGT feeding and 28% were able to tolerate oral feeding. Severe mucositis was seen in 104 TPN patients (72.2%) in comparison with 22 patients (26.2%) who were on Enteral Nutrition (EN) (p = <.001). Sinusoidal obstruction syndrome (SOS) was seen in 19 (13.2%) patients who had TPN compared to none in the patients who received EN (p = .001). The majority of patients who had SOS received myeloablative conditioning (MAC) therapy for hemoglobinopathy. Acute graft-versus-host disease (aGVHD) was seen in 24.8% of TPN patients and 9.1% of non-TPN patients (p = .01). However, there were no statistically significant differences in chronic GVHD, bacteremia, and patients' survival between both groups.

CONCLUSIONS

TPN is commonly used after pediatric HSCT in cases of severe mucositis. NGT feeding was found to be the least used nutritional support method. SOS and aGVHD were associated more frequently in TPN patients compared to EN patients. This suggests the possible disadvantages of TPN and importance of SOS preventative measures in high-risk patients.

Acute Kidney Injury in Hematopoietic Stem Cell Transplantation: A Review

Hematopoietic stem cell transplantation (HSCT) is a highly effective treatment strategy for lymphoproliferative disorders and bone marrow failure states including aplastic anemia and thalassemia. However, its use has been limited by the increased treatment related complications, including acute kidney injury (AKI) with an incidence ranging from 20% to 73%. AKI after HSCT has been associated with an increased risk of mortality. The incidence of AKI reported in recipients of myeloablative allogeneic transplant is considerably higher in comparison to other subclasses mainly due to use of cyclosporine and development of graft-versus-host disease (GVHD) in allogeneic groups. Acute GVHD is by itself a major independent risk factor for the development of AKI in HSCT recipients. The other major risk factors are sepsis, nephrotoxic medications (amphotericin B, acyclovir, aminoglycosides, and cyclosporine), hepatic sinusoidal obstruction syndrome (SOS), thrombotic microangiopathy (TMA), marrow infusion toxicity, and tumor lysis syndrome. The mainstay of management of AKI in these patients is avoidance of risk factors contributing to AKI, including use of reduced intensity-conditioning regimen, close monitoring of nephrotoxic medications, and use of alternative antifungals for prophylaxis against infection. Also, early identification and effective management of sepsis, tumor lysis syndrome, marrow infusion toxicity, and hepatic SOS help in reducing the incidence of AKI in HSCT recipients.

Single Daily Busulfan Dosing for Infants with Nonmalignant Diseases Undergoing Reduced-Intensity Conditioning for Allogeneic Hematopoietic Progenitor Cell Transplantation

Busulfan (Bu) is widely used in conditioning regimens for infants undergoing allogeneic hematopoietic progenitor cell transplantation (HPCT), but the best approach to administer Bu in this population is still unknown. Here, we report a single-center experience of the use of a test dose to guide dose adjustment of intravenous (i.v.) Bu therapy in infants. Between 2004 and 2013, 33 infants younger than 1 year with nonmalignant conditions received allogeneic peripheral blood or cord blood HPCT after a reduced-intensity conditioning (RIC) regimen consisting of fludarabine, antithymocyte globulin, and 2 single daily doses of i.v. Bu. Pharmacokinetic results of a test dose of i.v. Bu (.8 mg/kg) were used to determine the dose of 2 single daily i.v. Bu regimen doses, adjusted to target an area under the curve (AUC) of 4000 μMol*minute per day in a first cohort (n = 12) and 5000 μMol*minute in a second cohort (n = 21). The mean Bu clearance in our infant patients was found to be 3.67 ± 1.03 mL/minute/kg, and the test dose clearance was highly predictive of the regimen dose clearance. The mean AUC achieved after the first single daily regimen dose was 3951 ± 1239 in the AUC 4000 cohort and 4884 ± 766 for the AUC 5000 cohort. No patient in either cohort developed hepatic sinusoidal obstructive syndrome or seizures attributable to Bu. Primary graft failure occurred in 4 patients and secondary graft failure occurred in 3, predominantly in the AUC 4000 cohort (6 of 7). Among the engrafted patients (n = 28), 16 achieved full donor chimerism and 9 patients attained stable mixed chimerism. Overall survival of patients at 6 years after transplantation was 59.5% for the AUC 4000 cohort and 85.4% for the AUC 5000 cohort, with primary graft failure in the first cohort being a major contributor to morbidity. Logistic regression analysis showed that the risk of graft failure increased significantly if cord blood hematopoietic progenitor cells were used or if total Bu exposure was below 4000 μMol*minute per day for 2 days. The difference in clinical outcomes between the 2 cohorts supports the conclusion that targeting a higher Bu AUC of 5000 μMol*minute per day for 2 days improves donor engraftment in infants with nonmalignant conditions undergoing RIC HPCT without increasing toxicity. Measuring i.v. Bu pharmokinetics using a test dose allows timely adjustment of single daily regimen doses and optimization of total Bu exposure, resulting in an effective and safe regimen for these infants.

Sinusoidal obstruction syndrome (hepatic veno-occlusive disease)

Hepatic sinusoidal obstruction syndrome (SOS) is an obliterative venulitis of the terminal hepatic venules, which in its more severe forms imparts a high risk of mortality. SOS, also known as veno-occlusive disease (VOD), occurs as a result of cytoreductive therapy prior to hematopoietic stem cell transplantation (HSCT), following oxaliplatin-containing adjuvant or neoadjuvant chemotherapy for colorectal carcinoma metastatic to the liver and treated by partial hepatectomy, in patients taking pyrrolizidine alkaloid-containing herbal remedies, and in other particular settings such as the autosomal recessive condition of veno-occlusive disease with immunodeficiency (VODI). A central pathogenic event is toxic destruction of hepatic sinusoidal endothelial cells (SEC), with sloughing and downstream occlusion of terminal hepatic venules. Contributing factors are SEC glutathione depletion, nitric oxide depletion, increased intrahepatic expression of matrix metalloproteinases and vascular endothelial growth factor (VEGF), and activation of clotting factors. The clinical presentation of SOS includes jaundice, development of right upper-quadrant pain and tender hepatomegaly, ascites, and unexplained weight gain. Owing to the potentially critical condition of these patients, transjugular biopsy may be the preferred route for liver biopsy to exclude other potential causes of liver dysfunction and to establish a diagnosis of SOS. Treatment includes rigorous fluid management so as to avoid excessive fluid overload while avoiding too rapid diuresis or pericentesis, potential use of pharmaceutics such as defibrotide, coagulolytic agents, or methylprednisolone, and liver transplantation. Proposed strategies for prevention and prophylaxis include reduced-intensity conditioning radiation for HSCT, treatment with ursodeoxycholic acid, and inclusion of bevacizumab with oxaliplatin-based chemotherapeutic regimes. While significant progress has been made in understanding the pathogenesis of SOS and in mitigating against its adverse outcomes, this condition remains a serious complication of a selective group of medical treatments.