Standardizing Definitions of Hematopoietic Recovery, Graft Rejection, Graft Failure, Poor Graft Function, and Donor Chimerism in Allogeneic Hematopoietic Cell Transplantation: A Report on Behalf of the American Society for Transplantation and Cellular Therapy

Allogeneic hematopoietic cell transplantation (allo-HCT) is potentially curative for certain hematologic malignancies and nonmalignant diseases. The field of allo-HCT has witnessed significant advances, including broadening indications for transplantation, availability of alternative donor sources, less toxic preparative regimens, new cell manipulation techniques, and novel GVHD prevention methods, all of which have expanded the applicability of the procedure. These advances have led to clinical practice conundrums when applying traditional definitions of hematopoietic recovery, graft rejection, graft failure, poor graft function, and donor chimerism, because these may vary based on donor type, cell source, cell dose, primary disease, graft-versus-host disease (GVHD) prophylaxis, and conditioning intensity, among other variables. To address these contemporary challenges, we surveyed a panel of allo-HCT experts in an attempt to standardize these definitions. We analyzed survey responses from adult and pediatric transplantation physicians separately. Consensus was achieved for definitions of neutrophil and platelet recovery, graft rejection, graft failure, poor graft function, and donor chimerism, but not for delayed engraftment. Here we highlight the complexities associated with the management of mixed donor chimerism in malignant and nonmalignant hematologic diseases, which remains an area for future research. We recognize that there are multiple other specific, and at times complex, clinical scenarios for which clinical management must be individualized.

Chimeric antigen receptor T-cell therapy for marrow and extramedullary relapse of infant acute lymphoblastic leukemia

Chimeric antigen receptor (CAR) T-cells, engineered autologous T-cells that target antigens found in leukemia, have shown durable remissions in relapsed acute lymphoblastic leukemia (ALL). Infant ALL with KMT2A rearrangements (KMT2Ar) is a rare, aggressive form of leukemia associated with extramedullary disease both at diagnosis and at relapse, and overall outcomes for these patients are dismal. Here we report the successful use of tisagenlecleucel, a CAR T-cell product approved for relapsed/refractory ALL, in a patient with KMT2Ar infant ALL who was treated for combined marrow and extramedullary (renal) relapse.

The safety and efficacy of clofarabine in combination with high-dose cytarabine and total body irradiation myeloablative conditioning and allogeneic stem cell transplantation in children, adolescents, and young adults (CAYA) with poor-risk acute leukemia

Acute leukemias in children with CR3, refractory relapse, or induction failure (IF) have a poor prognosis. Clofarabine has single agent activity in relapsed leukemia and synergy with cytarabine. We sought to determine the safety and overall survival in a Phase I/II trial of conditioning with clofarabine (doses 40 - 52 mg/m²), cytarabine 1000 mg/m², and 1200 cGy TBI followed by alloSCT in children, adolescents, and young adults with poor-risk leukemia. Thirty-seven patients; Age 12 years (1-22 years); ALL/AML: 34:3 (18 IF, 10 CR3, 13 refractory relapse); 15 related, 22 unrelated donors. Probabilities of neutrophil, platelet engraftment, acute GvHD, and chronic GvHD were 94%, 84%, 49%, and 30%, respectively. Probability of day 100 TRM was 8.1%. 2-year EFS (event free survival) and OS (overall survival) were 38.6% (CI₉₅: 23-54%), and 41.3% (CI₉₅: 25-57%). Multivariate analysis demonstrated overt disease at time of transplant (relative risk (RR) 3.65, CI₉₅: 1.35-9.89, P = 0.011) and umbilical cord blood source (RR 2.17, CI₉₅: 1.33-4.15, P = 0.019) to be predictors of worse EFS/OS. This novel myeloablative conditioning regimen followed by alloSCT is safe and well tolerated in CAYA with very poor-risk ALL or AML. Further investigation in CAYA with better risk ALL and AML undergoing alloSCT is warranted.

Low day 100 transplant-related mortality (TRM) and relapse rate following clofarabine (CLO) in combination with cytarabine, total body irradiation (TBI), and allogeneic stem cell transplantation (AlloSCT) in children, adolescents, and young adults (CAYA) with poor-risk acute leukemia

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Background: CAYA with ALL or AML in third complete remission (CR3), refractory relapse (RR) or induction failure (IF) have an extremely poor prognosis, <20% EFS (Gaynon, BJH, 2005;Wells, JCO, 2003). CLO, an inhibitor of DNA polymerase and ribonucleotide reductase, has significant activity in CAYA with relapsed ALL/AML (Jeha, JCO 2006,2009) and synergy with cytarabine (Faderl, Blood, 2005). We sought to determine safety, day-100 TRM, and overall survival (OS) associated with CLO, cytarabine and TBI followed by AlloSCT in CAYA with poor-risk ALL/AML. Methods: This is a multi-center phase I/II trial of a novel conditioning regimen of CLO (dose escalation: 40mg/m2 [n=3], 46 mg/m2 [n=3], 52 mg/m2 [n=19]) x5d, sequential (4 hrs later) cytarabine 1000 mg/m2 x6d and TBI (1200cGy) followed by AlloSCT from matched related or unrelated donors in CAYA with ALL/AML in CR3, RR or IF. Patients with unrelated donors received R-ATG. GVHD prophylaxis consisted of tacrolimus and MMF (Bhatia/Cairo, BBMT, 2009). Kaplan-Meier method was used to determine the probabilities of engraftment, GVHD, TRM and OS. Results: 25 pts, median age: 11.3 yrs (1.5-20.7); M:F: 19:6, ALL/AML: 22:3 (10 CR3, 3 RR, 12 IF), 10 related donors, 15 unrelated donors (9 BM/PBSCs, 6 UCB). Median TNC and CD34 dose was 4.47x108/kg and 4.84x106/kg for BM/PBSCs and 4.0x107/kg and 2.8x105/kg for UCB, respectively. Probabilities of neutrophil, platelet engraftment and grade II-IV aGVHD were 100%, 92.9% and 47.5%, respectively. CLO dose was tolerable at 52mg/m2/d x5d without dose limiting toxicity. Probability of Day 100 TRM was only 4.3%. Probability of 1-yr PFS and OS were 51% (CI95: 28-71%), and 43% (CI95: 22-63%) respectively. Conclusions: Preliminary results suggest this novel regimen followed by AlloSCT is safe and well tolerated in CAYA with poor-risk ALL/ AML with CLO dose 52 mg/m2. Results are encouraging with respect to low risk of day 100 TRM and leukemic relapse associated with this conditioning regimen in this poor-risk population.

Association of Crohn's disease, thiopurines, and primary epstein-barr virus infection with hemophagocytic lymphohistiocytosis

OBJECTIVE

To assess the incidence of hemophagocytic lymphohistiocytosis (HLH) in a well-defined population of children with inflammatory bowel disease (IBD) and evaluate the common clinical and laboratory characteristics of individuals with IBD who developed HLH.

STUDY DESIGN

We conducted a retrospective study of all children who developed HLH over an 8-year period. The incidence of HLH in patients with IBD was calculated using US census data and a statewide project examining the epidemiology of pediatric IBD.

RESULTS

Among children in Wisconsin, 20 cases of HLH occurred during the study period; 5 cases occurred in children with IBD. Common characteristics include: Crohn's disease (CD), thiopurine administration, fever lasting more than 5 days, lymphadenopathy, splenomegaly, anemia, lymphopenia, and elevated serum triglycerides and ferritin. Of the patients, 4 had primary Epstein-Barr virus infections. The incidence of HLH among all children in Wisconsin was 1.5 per 100 000 per year. The risk was more than 100-fold greater for children with CD (P < .00001).

CONCLUSIONS

Pediatric patients with CD are at increased risk for developing HLH; primary Epstein-Barr virus infection and thiopurine administration may be risk factors.

Severe hypercholesterolemia mediated by lipoprotein X in a pediatric patient with chronic graft-versus-host disease of the liver

We describe a case of extreme hypercholesterolemia, mediated by lipoprotein X, in a 12-year-old Caucasian female who underwent an unrelated allogenic bone marrow transplant for relapsed acute myelocytic leukemia (AML). Her post-transplant course was complicated by severe chronic graft-versus-host disease (GVHD) of the liver. Previously normal serum cholesterol and triglycerides rose to 1,122 mg/dl (29.0 mmol/L) and 1,100 mg/dl (12.4 mmol/L), respectively. Serum cholesterol appeared to be dominantly carried by lipoprotein X. Intra-hepatic cholestasis leading to reflux of bile lipoproteins into the blood stream and subsequent formation of lipoprotein X appears to be the mechanism underlying this phenomenon.

Functional chiral asymmetry in descending thoracic aorta

To determine whether rotational blood flow or chiral asymmetry exists in the human descending thoracic aorta, we established the ability of color Doppler ultrasound to detect rotational flow in a tornado tube model of a vortex descending fluid column. In a model of the human aortic arch with a pulse duplicator, color Doppler was then used to demonstrate that rotational flow occurs first in the transverse arch and then in the proximal descending thoracic aorta. With the use of color Doppler esophageal echocardiography, 53 patients (age range, 25-78 years; mean age, 56.4 years) were prospectively examined for rotational flow in the descending thoracic aorta. At 10 cm superior to retro-left ventricular position, 22 of 38 patients (58%) revealed rotational flow with obvious diastolic counterclockwise rotation but less obvious systolic clockwise rotation. At 5 cm superior to retro-left ventricular position, 29 of 46 patients (63%) revealed rotational flow with a tendency toward systolic clockwise and diastolic counterclockwise rotation. At the retro-left ventricular position, 47 of 53 patients (89%) revealed rotational flow, usually of a clockwise direction, occurring in systole. Our data suggest that aortic flow is not purely pulsatile and axial but has a rotational component. Rotational flow begins in the aortic arch and is carried through to the descending thoracic aorta, where flow is chirally asymmetric with systolic clockwise and diastolic counterclockwise components. These data demonstrate an aortic rotational flow component that may have physiological implications for organ perfusion.

Echocardiographic practice in a large metropolitan area

A survey performed concerning echocardiography in a metropolitan area. Of 110 hospitals in the area, 62 reported having echocardiographic facilities. Echocardiographic physicians and/or technicians from 41 of these hospitals responded to questionnaires designed to determine the following: (1) educational background and credentials of technicians, (2) average salaries of technicians, (3) role of the physician and technician in the performance and reporting of echocardiograms, (4) volume, cost, and method of storage of echocardiograms, and (5) number and type of echocardiographic units in use. Our data suggest various trends, including a lack of formal training among technicians, the prevalence of cardiologists-internists as directors of echocardiographic facilities, the performance of echocardiograms by cardiology fellows in only 46% of institutions with cardiology training programs, and the widespread projected availability of cross-sectional echocardiographic capability within the next two years.

Cardiac pacemakers in absence of the SA node: responses to exercise and autonomic blockade

Surgical excision of the sinoatrial node, verified histologically, is followed by a supraventricular (atrial) rhythm in both resting and exercising dog whether anesthetized or conscious. The ECG is characterized by a definitive P wave and associated atrial electrograms. Waxing and waning in heart rate, generally referred to as sinus arrhythmia continues in the awake animal after complete excision of the SA node. This arrhythmia is responsive to both adrenergic and cholinergic interventions, thus indicating the presence of both sympathetic and parasympathetic regulation of subsidiary atrial pacemaking tissues.