Sinusoidal Obstruction Syndrome/Veno-Occlusive Disease after Autologous or Allogeneic Hematopoietic Stem Cell Transplantation in Children: a retrospective study of the Italian Hematology-Oncology Association–Hematopoietic Stem Cell Transplantation Group

Sinusoidal obstruction syndrome (SOS), also known as veno-occlusive disease (VOD), is a potentially life-threatening complication that may develop after hematopoietic stem cell transplantation (HSCT). The aims of this retrospective multicenter study were to evaluate the incidence of SOS/VOD in a large cohort of children transplanted in centers across Italy by applying the new European Society for Blood and Marrow Transplantation (EBMT) criteria and to analyze the risk factors underlying this complication. We retrospectively reviewed data of pediatric HSCTs performed in 13 AIEOP (Associazione Italiana di Ematologia e Oncologia Pediatrica)-affiliated centers between January 2000 and April 2016. The new pediatric EBMT criteria were retrospectively applied for diagnoses of SOS/VOD and severity grading. Among 5072 transplants considered at risk for SOS/VOD during the study period, 103 children (2%) developed SOS/VOD, and the grade was severe or very severe in all patients. The median time of SOS/VOD occurrence was 17 days after HSCT (range, 1 to 104). Sixty-nine patients (67%) were treated with defibrotide for a median time of 16 days (range, 4 to 104). In multivariable analysis age < 2 years, use of busulfan during the conditioning regimen, female gender, and hemophagocytic lymphohistiocytosis were risk factors statistically associated with the development of SOS/VOD. The overall mortality directly related to SOS/VOD was 15.5%. Overall survival at 1 year was worse in patients with SOS/VOD (P?=?.0033), and this difference disappeared 5 years after HSCT. Nonrelapse mortality was significantly higher 1 and 5 years after transplantation in patients who developed SOS/VOD (P < .001). Based on the application of new EBMT criteria, the overall incidence of SOS/VOD recorded in this large Italian pediatric retrospective study was 2%. Nonrelapse mortality was significantly higher in patients who developed SOS/VOD. Identifying the risk factors associated with SOS/VOD can lead to more effective early treatment strategies of this potentially fatal HSCT complication in childhood.     

Early Clinical Predictors of Hepatic Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome after Myeloablative Stem Cell Transplantation

Hepatic veno-occlusive disease (VOD), or sinusoidal obstruction syndrome (SOS), is a serious complication of hematopoietic stem cell transplantation (HSCT) with mortality in its severe form exceeding 80%. Although the incidence of VOD/SOS has fallen with contemporary transplantation practices, the increasing use of inotuzumab, the return of gemtuzumab, and the popularity of pharmacokinetic-guided high-dose busulfan may impact incidence. Early intervention with defibrotide improves survival, but prompt diagnosis can be difficult. We aimed to identify clinical parameters that could aid in early detection of VOD/SOS in a large, retrospective, cohort study. Of the 1823 adult patients who underwent myeloablative HSCT between 1996 and 2015 in our center, 205 (11%) developed VOD/SOS, with a median onset of day +14. We compared parameters in the 7 days preceding VOD/SOS onset for cases to 447 randomly selected control subjects in an analogous time frame to determine those with predictive value. Between 7 days before and the day of diagnosis, VOD/SOS patients had higher serum creatinine levels and were more likely to develop acute kidney injury (61% versus 33%, P < .0001), more commonly experienced refractoriness to platelet transfusion (48% versus 24%, P < .0001), and had higher trough serum tacrolimus levels (7 days before VOD/SOS onset: median 8.8 versus 7.3, P?=?.0002; day of onset: median 9.3 versus 7.2, P < .0001) compared with control subjects. Acute renal dysfunction, platelet refractoriness, and elevated or abnormal tacrolimus levels are dynamic clinical markers that should alert clinicians to the development of VOD/SOS before the presence of classical diagnostic criteria. Using these clinical features to recognize VOD/SOS earlier in its clinical course could promote earlier treatment and lead to improved outcomes of this potentially serious complication.     

Transjugular Intrahepatic Portosystemic Shunt for Very Severe Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome (VOD/SOS) after Unmanipulated Haploidentical Hematopoietic Stem Cell Transplantation with Post-transplantation Cyclophosphamide

Hepatic veno-occlusive disease or sinusoidal obstruction syndrome (VOD/SOS) is a threatening complication after both autologous and allogeneic hematopoietic stem cell transplantation (HSCT), with high mortality rates despite early medical treatment, including the use of defibrotide (DF). We retrospectively analyzed 185 unmanipulated haploidentical (haplo-) HSCT with post-transplantation cyclophosphamide as graft-versus-host disease prophylaxis performed consecutively between 2011 and June 2019 in a single center. Seventeen patients (9.2%) were diagnosed with VOD/SOS. Based on revised European Society for Blood and Marrow Transplantation severity criteria, the VOD/SOS cases were classified as mild in 2 patients (11.7%), moderate in 2 (11.7%), severe in 2 (11.7%), and very severe in 11 (64.9%). Thirteen patients (76%) were treated with DF, including all patients with severe or very severe VOD/SOS, except 1 patient with CNS hemorrhage. Sixteen patients (94%) were alive at day +100 after HSCT. Seven patients (41%) with very severe VOD/SOS were treated with transjugular intrahepatic portosystemic shunt (TIPS) owing to rapid clinical or analytical deterioration or refractory hepatorenal syndrome despite medical treatment, including DF. TIPS insertion was performed at a median time since VOD/SOS diagnosis of 4 days (range, 1 to 28 days) without technical complications in any case. The median hepatic venous pressure gradient before and after TIPS treatment was 24 mmHg (range, 14 to 29 mmHg) and 7 mmHg (range, 2 to 11 mmHg), respectively, with a median drop of 16 mmHg (range, 9 to 19 mmHg). Following TIPS insertion, all patients showed clinical improvement with hepatomegaly, ascites, and renal failure resolution, and all showed analytical improvement with reduced alanine aminotransferase (ALT), creatinine, and international normalized ratio values, except for patient 2, whose indication for TIPS was refractory hepatorenal syndrome with a normal ALT level. The 6 patients who had initiated DF before TIPS insertion completed 21 days of treatment. All patients met the criteria for complete remission (CR) at a median of 8 days after TIPS insertion (range, 2 to 82 days). The 100-day overall survival was 100%. For patients with rapid progressive VOD/SOS, early TIPS insertion allowed completion of DF therapy. The use of TIPS together with DF resulted in CR and no associated complications with no VOD/SOS-associated mortality despite high severity. In our experience, timely and individualized use of TIPS significantly improves outcomes of very severe VOD/SOS after haplo-HSCT. Therefore, TIPS should be promptly considered in rapidly progressive cases.     

Liver Stiffness Measurement Allows Early Diagnosis of Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome in Adult Patients Who Undergo Hematopoietic Stem Cell Transplantation: Results from a Monocentric Prospective Study

Veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome (SOS), is a life-threatening complication affecting patients undergoing hematopoietic stem cell transplantation (HSCT). The survival rate is higher when specific therapy is initiated early; thus, improving early, noninvasive diagnosis of VOD/SOS is an important need. In an adult population undergoing HSCT, we aimed to assess the role of liver stiffness measurement (LSM), evaluated by transient elastography (TE), for diagnosing VOD/SOS. Between April 2016 and March 2018, 78 consecutive adult patients with indications for allogeneic HSCT were prospectively included. LSM was performed before HSCT and at days +9/10, +15/17, and +22/24 post-HSCT. New European Society for Blood and Marrow Transplantation criteria were used to establish VOD/SOS diagnosis. Four patients developed VOD/SOS (5.1%) during the study period, with a median time of +17 days post-HSCT. A sudden increase in LSM compared with previously assessed values and pre-HSCT values, was seen in all patients who developed VOD/SOS. LSM increases occurred from 2 to 12 days before clinical SOS/VOD appearance. The VOD/SOS diagnostic performance of increased LSM over pre-HSCT assessment showed an area under the receiver operating characteristic curve of 0.997 (sensitivity 75%; specificity 98.7%). LSM gradually decreased following successful VOD/SOS-specific treatment. Interestingly, LSM values did not increase significantly in patients experiencing hepatobiliary complications (according to the Common Terminology Criteria) other than VOD/SOS. LSM by TE can be considered a promising method to perform an early, preclinical diagnosis and follow-up of VOD/SOS.     

Combination of High-Dose Methylprednisolone and Defibrotide for Veno-Occlusive Disease in Pediatric Hematopoietic Stem Cell Transplant Recipients

Veno-occlusive disease (VOD) is a serious complication of hematopoietic stem cell transplant (HSCT), with high mortality in severe cases and until recently very limited therapeutic options consisting largely of supportive care. Defibrotide was recently approved in the United States for the treatment of severe VOD in patients with renal or pulmonary dysfunction after HSCT. Our group previously published on the use of high-dose methylprednisolone (500?mg/m² per dose every 12 hours for 6 doses) in patients with VOD, showing good success. A small subset of these individuals were also treated with defibrotide, but additional studies using the combination of high-dose methylprednisolone and defibrotide for the treatment of VOD are lacking. We present a single-institution retrospective chart review of 15 HSCT patients with VOD treated with the combination of high-dose methylprednisolone and defibrotide. VOD developed at a median of 17 days post-HSCT, and combination therapy was initiated within 1 day of VOD diagnosis. Twelve of 15 patients (80%) had multiorgan failure. Our single-center experience using both high-dose methylprednisolone and defibrotide showed a day +100 survival rate of 73% and an overall VOD complete resolution rate of 66.7%, higher than the rates reported in the recent literature using defibrotide alone (40% to 50% day +100 overall survival). These data suggest that the combination of high-dose steroids and defibrotide may be superior to defibrotide alone and warrant further investigation.     

High-Dose Methylprednisolone for Veno-Occlusive Disease of the Liver in Pediatric Hematopoietic Stem Cell Transplantation Recipients

Veno-occlusive disease (VOD) of the liver is a well-recognized serious complication of hematopoietic stem cell transplantation (HSCT), with few successful treatment modalities available for severe disease. Some reports have demonstrated success in adults with the use of high-dose steroid therapy, but experience in the pediatric population is lacking. We retrospectively reviewed HSCT patients treated at our institution since 2003 and identified 15 (2.4%) who developed VOD. Of these, nine (60%) were treated with intravenous high-dose methylprednisolone (500 mg/m² per dose every 12 hours for six doses). Steroid therapy was initiated at or before first ultrasound evidence of reversal of portal venous flow and before meeting criteria for initiation of defibrotide therapy. Four patients were also treated with defibrotide starting 2 to 5 days after initiation of steroids. Eight of nine patients (88%) with VOD were diagnosed with multiorgan failure. Response to high-dose steroid therapy as defined by decrease in bilirubin by 50% in 10 days from therapy initiation was noted in six of nine patients (67%), occurring within 3 to 6 days of steroid therapy. Two patients died from multiorgan failure due to VOD. Seven survivors of VOD recovered at the median 6 days (range, 5 to 38) from VOD diagnosis. Overall, VOD survival as a group was 78%; however, survival among responders was 100%. No serious toxicities related to high-dose steroid therapy were observed. We conclude that high-dose steroid therapy if initiated early may reverse VOD of the liver in pediatric HSCT patients, abrogating the need for defibrotide therapy with its associated toxicities and regulatory difficulties.     

Novel Ultrasonographic Scoring System of Sinusoidal Obstruction Syndrome after Hematopoietic Stem Cell Transplantation

Sinusoidal obstruction syndrome (SOS)/hepatic veno-occlusive disease (VOD) is a well-documented complication after hematopoietic stem cell transplantation (HSCT). Transabdominal ultrasonography (US) enables the visualization of blood flow abnormalities and is therefore useful for the diagnosis of SOS/VOD. We herein prospectively evaluated accuracy of a novel US diagnostic scoring system of SOS/VOD based on US findings. We carried out US in 106 patients on day 14 and when SOS/VOD was suspected after allogeneic HSCT. Among 106 patients, 10 patients (9.4%) were diagnosed as SOS/VOD by Baltimore or Seattle criteria. According to univariate analysis of 17 US findings (US-17 screening), we established a novel scoring system (HokUS-10) consisting of 10 parameters, such as gallbladder wall thickening, ascites, and blood flow signal in the paraumbilical vein. The sensitivity and specificity were 100% and 95.8%, respectively. Diagnostic performance of the HokUS-10 was significantly better than US-17 screening. In 4 of 10 patients US detection of SOS/VOD preceded to clinical diagnosis. The HokUS-10 scoring system is useful in the diagnosis of SOS/VOD; however, our results should be validated in other cohorts.     

Incidence of Anicteric Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome and Outcomes with Defibrotide following Hematopoietic Cell Transplantation in Adult and Pediatric Patients

Veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a potentially life-threatening complication of hematopoietic cell transplantation (HCT) that is traditionally diagnosed using Baltimore or modified Seattle criteria. Whereas the Baltimore criteria require the presence of hyperbilirubinemia (bilirubin ≥2 mg/dL) for a diagnosis of VOD/SOS, the modified Seattle criteria do not. Before approval by the US Food and Drug Administration, defibrotide was available in the United States through an expanded-access study (T-IND). The T-IND protocol initially required post-HCT diagnosis of VOD/SOS by the Baltimore criteria or biopsy but was later amended to include patients diagnosed using the modified Seattle criteria. This post hoc analysis examined the incidence of VOD/SOS with a bilirubin level <2 mg/dL before and after Day 21 post-HCT in T-IND patients enrolled following the amendment allowing for diagnosis by the modified Seattle criteria. Survival of adult and pediatric patients with or without hyperbilirubinemia and with or without multiorgan dysfunction (MOD) was also evaluated. Of 803 post-HCT patients with VOD/SOS enrolled following the protocol amendment, 181 (23%) had a bilirubin level <2 mg/dL and would not have been diagnosed if hyperbilirubinemia was required. The bilirubin level at diagnosis was <2 mg/dL in 165 of 331 patients (50%) diagnosed by the modified Seattle criteria and in 16 of 23 patients (70%) diagnosed by biopsy. VOD/SOS with a bilirubin level <2 mg/dL was more common in pediatric patients (29%), although it also occurred in adult patients (15%). Patients with hyperbilirubinemia had lower Day 100 survival (54% versus 87% in patients with bilirubin <2 mg/dL) and a higher incidence of MOD (41% versus 26% in patients with bilirubin <2 mg/dL). The incidence of treatment-emergent adverse events and serious adverse events was lower in patients with a bilirubin level <2 mg/dL. These results indicate that anicteric VOD/SOS occurs in both adult and pediatric patients post-HCT and can be diagnosed before and after Day 21 in both groups. The worse survival in patients with bilirubin ≥2 mg/dL suggests that requiring hyperbilirubinemia may result in a progressed disease stage associated with worse outcomes. Taken together, these results highlight the importance of awareness and the possibility of VOD/SOS in the absence of elevated bilirubin level.     

Incidence,Predictors, and Outcomes of Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome after Reduced-Intensity Allogeneic Hematopoietic Cell Transplantation

fludarabine with intravenous busulfan at doses of 3.2 mg/kg (Flu/Bu1) or 6.4 mg/kg (Flu/Bu2). Hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a serious complication of hematopoietic stem cell transplantation (HCT) that is felt to be triggered, at least in part, by damage to the liver sinusoidal endothelium from cytotoxic conditioning regimens. Accordingly, the incidence of VOD/SOS after reduced-intensity conditioning (RIC) HCT is low compared with myeloablative transplantation, and the natural history, risk factors, and outcomes of VOD/SOS after RIC have not been well characterized. We retrospectively reviewed 1583 consecutive patients receiving RIC HCT at the Dana-Farber Cancer Institute between 2007 and 2017 and ascertained 26 cases of VOD/SOS. The median day of VOD/SOS onset was 26 days (range, 5 to 48) and the cumulative incidence at day 50 was 1.6% (95% confidence interval [CI], 1.1% to 2.4%). Day 100 nonrelapse mortality rate was 23% in the VOD/SOS cohort compared with 6.4% in patients without VOD/SOS (P = .006). Cumulative incidence of VOD/SOS at day 50 was 3.1% after RIC regimen with Flu/Bu2 ± ATG (fludarabine with two doses of busulfan, total dose 6.4 mg/kg, with or without anti-thymocyte globulin), compared with 0.15% after Flu/Bu1 ± ATG (fludarabine with single busulfan dose 3.2 mg/kg, with or without anti-thymocyte globulin) (P = .0002); the incidence rate was 2.1% after RIC HCT with sirolimus-containing graft-versus-host disease prophylaxis, compared with 0.8% for RIC without sirolimus (P = .06). Significant risk factors identified in multivariable analysis for the development of VOD/SOS were sirolimus use (hazard ratio [HR], 5.1; 95% CI, 1.8 to 14.2; P = .002) and RIC regimen with Flu/Bu2 ± ATG (HR, 34; 95% CI, 4.5 to 252; P < .001) or other (HR, 32; 95% CI, 3.9 to 257; P = .001) compared with Flu/Bu1 ± ATG. Rising serum tacrolimus or sirolimus levels, new acute kidney injury, and increasing platelet transfusion requirements were significant early predictors of onset in the week preceding prior VOD/SOS diagnosis. When compared with a previously published cohort of 76 patients with VOD/SOS who developed VOD/SOS after myeloablative HCT in the same time period, VOD/SOS after RIC occurred later and was associated with a lower peak bilirubin level and better overall survival. The variability in presenting features for RIC VOD/SOS highlights the importance of maintaining a high index of suspicion for this entity in RIC HCT.     

Prevention of veno-occlusive disease with defibrotide after allogeneic stem cell transplantation.

Veno-occlusive disease (VOD) of the liver occurs in 10% to 50% of patients after allogeneic stem cell transplantation, ranging from mild reversible disease to severe disease, with a mortality rate almost always close to 100%. Recently, promising results in the treatment of established VOD with defibrotide were reported. Therefore, defibrotide may be used as a prophylactic regimen for hepatic VOD in stem cell transplantation for hematologic malignancies. Fifty-two successive patients who underwent transplantation between October 1999 and June 2002 received defibrotide prophylaxis intravenously from day -7 to day +20 after transplantation in addition to heparin and were compared with historical controls who underwent transplantation successively between February 1997 and September 1999. In the defibrotide group, the maximum total bilirubin levels and the number of patients with serum levels exceeding 50 micromol/L were significantly lower than in the control group (5 of 52 versus 18 of 52, respectively; P =.004). None of the 52 patients developed VOD (Baltimore criteria), and no side effects occurred. These results were significantly different (P =.001) from controls (10/52 [19%] with VOD, 3 of whom died of severe VOD). In addition, day 100 event-free survival was significantly higher in the study group (P =.02), with a trend toward better day 100 overall survival (P =.07). These results suggest that defibrotide given in addition to heparin may be an efficient prophylaxis for VOD.     

Refractory Thrombocytopenia Is a Valid Early Diagnostic Criteria for Hepatic Veno-Occlusive Disease in Children

We compared the incidence of refractory thrombocytopenia (RT) and platelet transfusion requirements (PTR) in 35 children who developed veno-occlusive disease (VOD) with 35 matched control subjects who underwent hematopoietic stem cell transplant but did not develop VOD. RT developed in 100% of the VOD patients, at a median of 8 days before VOD diagnosis, as compared with 71.5% of the control group. VOD patients required more platelet transfusions than control subjects (median PTR, 6.9 mL/kg [range, .57 to 17.59] versus 3.57 mL/kg [range, 0 to 14.63], respectively) with a statistically significant difference (P < .0001). The number of days with platelet requirements was significantly higher for VOD patients as compared with control subjects (median 68% versus 39%, P =< .0001). The PTR peaked at ~12 mL/kg/day, 2 days before VOD diagnosis, whereas the PTR in the control population was 5 mL/kg/day. The positive predictive value of developing VOD was 88.9% (95% confidence interval, 66.5% to 97%) in patients who were given >7 mL/kg/day of platelets during the at-risk period of days +3 to +13 after transplant. For patients who received >8 mL/kg/day of platelets, the positive predictive value of developing VOD was 86.7% (95% confidence interval, 61.2% to 96.4%). There was no difference in the PTR in patients with mild to moderate VOD as compared with severe VOD; however, the PTR was higher in patients whose VOD did not resolve. The median daily PTR after the diagnosis of VOD in 17 patients who got defibrotide as compared with those who did not get defibrotide was 6.04 mL/kg and 5.72 mL/kg, respectively, but the difference was not statistically significant (P = .56). On univariate and multivariate analysis use of intravenous immunoglobulin was significantly associated with VOD (P = .0088) but was not significantly associated with fatal VOD. In conclusion, RT occurs in 100% of patients at a median of 8 days before VOD diagnosis. VOD should be suspected in any patient with RT after the exclusion of other causes of consumptive thrombocytopenia, especially if they require >7 mL/kg/day of platelets.     

儿童造血干细胞移植患者人巨细胞病毒与疱疹病毒6型感染及相互关系

目的 了解儿童造血干细胞移植患者术后人巨细胞病毒与疱疹病毒6型的感染情况以及相互关系.方法 患者为2007年6月至2009年10月间北京儿童医院血液病中心的造血干细胞移植的患儿,患儿术后每周采集外周静脉血,分别应用荧光定量PCR和常规PCR检测患者血清中CMV DNA载量及外周全血中HHV-6,并对HHV-6进行分型.结果 共52例造血干细胞移植患者,636份标本.20例造血干细胞移植患者共52份标本CMV-DNA检测阳性,中位检出时间为术后56d.CMV感染的总发生率为38.5%（20/52）.其中异基因造血干细胞移植CMV感染的发病率为47.6%（20/42）,晚发性CMV感染的发生率为22.2%（6/27）.3例CMV感染患者死亡,其中2例诊断CMV间质性肺炎.14例患者共33份血标本HHV-6 PCR阳性,中位检出时间为术后23d,HHV6感染的总发生率为26.9%（14/52）,其中异基因HSCT患者HHV6感染的发生率为31%（13/42）,且均为B型.20例CMV阳性的造血干细胞移植患者中,有6例发生CMV感染,HHV-6与CMV共感染率为30%（6/20）.结论 儿童造血干细胞移植患者术后CMV感染率和HHV-6感染率均较高,造血干细胞移植术后发生较早的HHV-6感染和发生较晚的CMV感染之间的关系有待进一步研究.     

Graft-versus-Host disease Prophylaxis with Everolimus and Tacrolimus Is Associated with a High Incidence of Sinusoidal Obstruction Syndrome and Microangiopathy: Results of the EVTAC Trial

A calcineurin inhibitor combined with methotrexate is the standard prophylaxis for graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation (HSCT). Everolimus, a derivative of sirolimus, seems to mediate antileukemia effects. We report on a combination of everolimus and tacrolimus in 24 patients (median age, 62 years) with either myelodysplastic syndrome (MDS; n = 17) or acute myeloid leukemia (AML; n = 7) undergoing intensive conditioning followed by HSCT from related (n = 4) or unrelated (n = 20) donors. All patients engrafted, and only 1 patient experienced grade IV mucositis. Nine patients (37%) developed acute grade II-IV GVHD, and 11 of 17 evaluable patients (64%) developed chronic extensive GVHD. Transplantation-associated microangiopathy (TMA) occurred in 7 patients (29%), with 2 cases of acute renal failure. The study was terminated prematurely because an additional 6 patients (25%) developed sinusoidal obstruction syndrome (SOS), which was fatal in 2 cases. With a median follow-up of 26 months, the 2-year overall survival rate was 47%. Although this new combination appears to be effective as a prophylactic regimen for acute GVHD, the incidence of TMA and SOS is considerably higher than seen with other regimens.     

Prophylactic low-dose heparin or prostaglandin E1 may prevent severe veno-occlusive disease of the liver after allogeneic hematopoietic stem cell transplantation in Korean children

Studies investigating the effect of prophylactic drugs on hepatic veno-occlusive disease (VOD) development are rare in children that have undergone allogeneic hematopoietic stem cell transplantation (HSCT). This study examined risk factors for VOD, the effect of prophylactic low-dose heparin or lipo-prostaglandin E1 (lipo-PGE1) and the survival rate at day +100 in children undergoing allogeneic HSCT. Eighty five children underwent HSCT between June 1997 and September 2004. Patients were diagnosed and classified as having mild, moderate or severe VOD according to Seattle clinical criteria. Among 85 patients, 25 (29%) developed VOD. VOD occurred more frequently in patients receiving busulfan-based conditioning (24/65, 37%) than in those receiving TBI-based (1/10, 10%) or other (0/10, 0%) regimens (p<0.05). The incidence of VOD was lower in patients with non-malignant disease compared to those with malignant disease (p<0.05). Survival at day +100 for non-VOD patients was better than that for VOD patients (92% vs. 76%, p<0.05). No patients receiving prophylactic heparin or lipo-PGE1 were found to develop severe VOD, whereas 5 of 35 patients not receiving such prophylaxis developed severe VOD. Given severe VOD is associated with a high mortality rate, this study indicates that prophylactic heparin or lipo-PGE1 may decrease mortality in children undergoing HSCT.     

Risk Factors for Development of and Progression of Hepatic Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome

Veno-occlusive disease, also known as sinusoidal obstruction syndrome (VOD/SOS), is a potentially life-threatening complication of allogeneic or autologous hematopoietic stem cell transplantation (HSCT) most commonly associated with high-intensity chemotherapies. The development of VOD/SOS may be rapid and unpredictable, and the importance of identifying risk factors to facilitate prompt diagnosis and timely treatment has become increasingly recognized. The reporting of new retrospective study data for adults and children and the emergence of novel anticancer therapies that may increase the risk of VOD/SOD also necessitate updates on risk factors, as provided in this review. The latest studies reporting VOD/SOS risk factors support previously published data, although the importance of patient-related factors, such as acute kidney injury, increased international normalized ratio, female sex (in children), and platelet refractoriness, is given greater emphasis in the recent data. Non-transplantation-related chemotherapies associated with increased risk for VOD/SOS include oxaliplatin and 5-fluorouracil chemotherapies. The novel antibody drug conjugates gemtuzumab ozogamicin and inotuzumab ozogamicin are now reported in product labeling to pose risks for VOD/SOS based on clinical trial data; an expert consensus panel has issued recommendations for risk reduction measures with inotuzumab ozogamicin treatment, including VOD/SOS prophylaxis and limitation to ≤2 inotuzumab ozogamicin treatment cycles. A wide range of biomarkers, including genetic, hematologic, hepatic, and inflammatory factors, as well as novel diagnostic techniques such as thromboelastography and measures of liver stiffness, may further enhance future risk calculation for VOD/SOS, although none has been widely adopted. Continual monitoring for and recognition of VOD/SOS risk factors are essential for optimal management of this complication.     

Prior Gemtuzumab Ozogamicin Exposure in Adults with Acute Myeloid Leukemia Does Not Increase Hepatic Veno-Occlusive Disease Risk after Allogeneic Hematopoietic Cell Transplantation: A Center for International Blood and Marrow Transplant Research Analysis

Gemtuzumab ozogamicin (GO) therapy before allogeneic hematopoietic cell transplantation (alloHCT) has been historically associated with an increased risk of hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) in patients with acute myeloid leukemia (AML). The current analysis examined VOD/SOS risk and outcomes in a cohort of patients who in recent years were reported to the Center for International Blood and Marrow Transplant Research. Adults with AML who had GO exposure before myeloablative alloHCT were matched 1:4 by age and disease status at transplant to recipients without GO exposure (control subjects). One hundred thirty-seven patients with GO exposure and 548 matched control subjects who underwent alloHCT between 2008 and 2011 were included in this analysis. With a median ∼8-year follow-up of survivors, the 5-year overall survival probability was similar in the 2 cohorts: 38% and 38% in the GO-exposed versus control groups (P = .97). Incidence of VOD/SOS and severe VOD/SOS, respectively, at 100 days was 4% (95% confidence interval [CI], 1% to 7%) and 3% (95% CI, 1% to 6%) in GO-exposed patients and 3% (95% CI, 2% to 5%) and 1% (95% CI, 0% to 2%) in control subjects. Correspondingly, among patients who developed VOD/SOS, 1-year survival probability after VOD/SOS diagnosis was 33% (95% CI, 5% to 72%) and 27% (95% CI, 11% to 47%; P = .78). In multivariate analyses, GO exposure before alloHCT was not associated with an increased risk of VOD/SOS (odds ratio, 1.10; P = .85) or death (hazard ratio, 1.08; P = .57). Three deaths (3%) in the GO group and 3 deaths (<1%) in the control group were attributed to VOD/SOS. Our results suggest that GO treatment before myeloablative alloHCT in the recent era is not associated with an increased risk of post-transplant VOD/SOS or death.     

Increased Incidence of Nocardial Infections in an Era of Atovaquone Prophylaxis in Allogeneic Hematopoietic Stem Cell Transplant Recipients

Nocardial infections have been rare after allogeneic hematopoietic stem cell transplantation (HSCT). We report 10 recent cases of late-onset nocardiosis (median time of onset of 508 days after transplantation) primarily in patients on high doses of corticosteroids for graft-versus-host disease. All 10 patients had pulmonary infection caused by Nocardia species susceptible to trimethoprim-sulfamethoxazole (TMP-SMX). At time of diagnosis 8 of 10 patients were not receiving TMP-SMX for prophylaxis of Pneumocystis jiroveci pneumonia (PJP; 7 on atovaquone, 1 on i.v. pentamidine). After the initiation of atovaquone prophylaxis for PJP in place of TMP-SMX for many UCLA allogeneic HSCT patients in 2012, 9 cases of nocardiosis occurred in 411 patients (2.2%) over the next 6 years (2012 to 2017) compared with only 1 case in 575 patients (0.17%) during the previous 12 years (2000 to 2011). Although there were no deaths directly related to nocardial infection treated primarily with TMP-SMX, overall mortality in this group of patients was 40%. Based on this experience, the use of atovaquone for PJP prophylaxis in place of TMP-SMX may be associated with an increased risk for previously rare nocardial infections after allogeneic HSCT.     

The incidence and risk factors of invasive fungal infection after haploidentical haematopoietic stem cell transplantation without in vitro T-cell depletion

In recent years, we have successfully established a novel method of haploidentical haematopoietic stem cell transplantation (HSCT) without in vitro T-cell depletion. This study was aimed at analysing the incidence and risk factors of invasive fungal infection (IFI) with this transplantation method. The study comprised 291 patients who had undergone haploidentical HSCT from 1 January 2007 to 31 December 2008. IFI was diagnosed according to the European Organization for Research and Treatment of Cancer/Mycoses Study Group 2002 criteria, and only proven or probable cases of IFI were regarded as true cases. A total of 39 patients were documented as having IFI, including four proven cases and 35 probable cases. The median time of diagnosis was 26 days (range: 6-405 days) after transplantation. The cumulative incidence rates of IFI at 40 days, 1 year, 2 years and 3 years after transplantation were 8.25%, 13.1%, 13.4% and 13.4%, respectively. Multivariate analysis identified platelet engraftment time (>17 days) (p 0.027; hazard ratio (HR) 2.432; 95% CI 1.105-5.355), a high risk of underlying disease (p 0.001; HR 2.916; 95% CI 1.515-5.611) and grade III-IV acute graft-versus-host disease (p 0.019; HR 2.407; 95% CI 1.154-5.022) as risk factors for IFI. The incidence rates of IFI in patients with no, one, two or three risk factors at 3 years after transplantation were 4.48%, 7.86%, 29.6% and 23.1%, respectively. In conclusion, IFI is an important complication following haploidentical HSCT without in vitro T-cell depletion.     

Risk of reactivated toxoplasmosis in haematopoietic stem cell transplant recipients: a prospective cohort study in a setting withholding prophylaxis

ObjectivesReactivation of latent toxoplasmosis may be life-threatening in haematopoietic stem cell transplant (HSCT) recipients. We conducted an 8-year-long prospective study on the diagnosis and monitoring of reactivated toxoplasmosis in paediatric HSCT recipients. The primary objective was to determine the incidence of reactivated toxoplasmosis in a setting that withholds prophylaxis until engraftment. The second objective was to identify the subgroups of HSCT recipients particularly prone to reactivation who may benefit the most from regular PCR follow-up.MethodsSerological and qPCR screening targeting the Toxoplasma 529 bp gene was performed before HSCT, and continued by weekly monitoring after HSCT for a median time of 104 days.ResultsReactivated toxoplasmosis was diagnosed in 21/104 (20.2%), predominantly in allo- (19/75) and rarely in auto-HSCT (2/29) recipients. Over 50% (14/21) of cases were diagnosed during the first month after HSCT, while awaiting engraftment without prophylaxis. Toxoplasma disease evolved in only three (14.3%, 3/21) patients, all treated by allo-HSCT. Reactivation was more frequent in patients treated for acute lymphoblastic leukaemia (3/27, p 0.03) and especially, in recipients of haploidentical stem cells (10/20, p 0.005). Seronegative status of the donor (where was known) contributed to 75% (12/16) cases of reactivated toxoplasmosis after allo-HSCT.DiscussionThe presented results show that peripheral blood-based qPCR, both before and after HSCT, is a valuable asset for the diagnosis of reactivated toxoplasmosis, whereas the results of serology in recipients should be interpreted with caution. Weekly qPCR monitoring, at least until successful engraftment and administration of prophylaxis, allows for prompt introduction of specific treatment.     

Outcomes of Allogeneic Hematopoietic Stem Cell Transplantation in Adult Patients with Myelodysplastic Syndrome Harboring Trisomy 8

Trisomy 8 (+8) is 1 of the most common cytogenetic abnormalities in adult patients with myelodysplastic syndrome (MDS). However, the outcome of allogeneic hematopoietic stem cell transplantation (HSCT) in adult patients with MDS harboring +8 remains unclear. To evaluate the outcome and prognostic factors in patients with MDS harboring +8 as the sole cytogenetic abnormality or in association with other abnormalities, we retrospectively analyzed the Japanese registration data of 381 adult patients with MDS harboring +8 treated with allogeneic HSCT between 1990 and 2013. With a median follow-up period of 53 months, the probability of overall survival and cumulative incidence of relapse at 4 years were 51% and 22%, respectively. In the multivariate analysis, age > 50 years, 2 or more additional cytogenetic abnormalities, and a high risk at the time of HSCT according to the FAB/WHO classification were significantly associated with a higher overall mortality. Nevertheless, no significant impact of the outcome was observed in patients with 1 cytogenetic abnormality in addition to +8. Although 221 patients (58%) had advanced MDS at the time of HSCT, allogeneic HSCT offered a curative option for adult patients with MDS harboring +8.