Association of early donor chimerism status with survival outcomes in post allogeneic hematopoietic stem cell transplant patients of nonmalignant diseases

Objective: To highlight the association of early donor chimerism status at 2nd month with various survival outcomes. Method: The retrospective study was conducted at the Armed Forces Bone Marrow Transplant Centre, Rawalpindi, Pakistan, and comprised patient data from January 2011 to July 2016. Data related to participants who underwent human leukocyte antigen-matched transplants for bone marrow failure syndrome and beta thalassemia major. Short tandem repeat-based polymerase chain reaction was used to assess donor chimerism status. Overall survival, disease-free survival, relapse-free survival, and graft versus host disease-free survival rates were noted. Data was analysed using SPSS 23. Results: Of the 106, 64(60.4%) had bone marrow failure syndrome and 42(39.6%) had beta thalassemia major. The overall median follow-up was 13.53 months (range: 1.81-62.73 months). Early donor chimerism status was associated with overall survival (p=0.02) and disease-free survival (p=0.01). Mixed donor chimerism was less hazardous in terms of overall survival (p=0.04) and disease-free survival (p=0.02). Conclusion: Early mixed donor chimerism contributed to optimal survival in nonmalignant disease. Key Words: Hematopoietic stem cell transplantation, Nonmalignant diseases, Survival outcome, Conditioning regimen.

Diamond-Blackfan anemia

Diamond-Blackfan anemia (DBA) is an inherited bone marrow failure syndrome, characterized as a rare congenital bone marrow erythroid hypoplasia (OMIM#105650). Erythroid defect in DBA results in erythroblastopenia in bone marrow as a consequence of maturation blockade between the burst forming unit–erythroid and colony forming unit–erythroid developmental stages, leading to moderate to severe usually macrocytic aregenerative (<20 × 109/L of reticulocytes) anemia. Congenital malformations localized mostly in the cephalic area and in the extremities (thumbs), as well as short stature and cardiac and urogenital tract abnormalities, are a feature of 50% of the DBA-affected patients. A significant increased risk for malignancy has been reported. DBA is due to a defect in the ribosomal RNA (rRNA) maturation as a consequence of a heterozygous mutation in 1 of the 20 ribosomal protein genes. Besides classical DBA, some DBA-like diseases have been identified. The relation between the defect in rRNA maturation and the erythroid defect in DBA has yet to be fully defined. However, recent studies have identified a role for GATA1 either due to a specific defect in its translation or due to its defective regulation by its chaperone HSP70. In addition, excess free heme-induced reactive oxygen species and apoptosis have been implicated in the DBA erythroid phenotype. Current treatment options are either regular transfusions with appropriate iron chelation or treatment with corticosteroids starting at 1 year of age. The only curative treatment for the anemia of DBA to date is bone marrow transplantation. Use of gene therapy as a therapeutic strategy is currently being explored.

Hematologic Complications with Age in Shwachman-Diamond Syndrome

Shwachman-Diamond Syndrome (SDS) is an inherited bone marrow failure syndrome with leukemia predisposition. An understanding of the hematologic complications of SDS with age could guide clinical management, but data are limited for this rare disease. We conducted a cohort study of 153 subjects from 143 families with confirmed biallelic SBDS mutations enrolled on the North American Shwachman Diamond Registry or Bone Marrow Failure Registry. The SBDS c.258+2T>C variant was present in all but one patient. To evaluate association of blood counts with age, a total of 2146 blood counts were analyzed for 119 subjects. Absolute neutrophil counts were positively associated with age (P<0.0001). Hemoglobin was also positively associated with age up to 18 years (P<0.0001) but thereafter the association was negative (P=0.0079). Platelet counts and marrow cellularity were negatively associated with age (P<0.0001). Marrow cellularity did not correlate with blood counts. Severe marrow failure necessitating transplant developed in 8 subjects at a median age of 1.7 years (range 0.4-39.5), with 7 of 8 requiring transplant prior to age 8 years. Twenty-six subjects (17%) developed a myeloid malignancy (16 MDS and 10 AML) at a median age of 12.3 years (range 0.5-45.0) for MDS, and 28.4 years (range 14.4-47.3) for AML. A lymphoid malignancy developed in one patient at the age of 16.9 years. Hematologic complications were the major cause of mortality (17/20 deaths, 85%). These data inform surveillance of hematologic complications in SDS.

Outcomes of Haploidentical Stem Cell Transplantation in Patients with Fanconi Anemia; A Systematic Review

Introduction Fanconi anemia (FA) is the most common inherited cause of bone marrow failure syndrome, with an incidence of approximately 1 out of 100,000 births per year and a prevalence of 1 in 360 000 live births. Clinical presentation is variable, ranging from classic Fanconi phenotype to absence of somatic abnormalities. Despite advances in understanding disease genetics and pathogenesis, hematopoietic stem cell transplant (HSCT) remains the only curative treatment option for FA patients. However, the future risk of solid organ malignancies persists post-transplant. Although outcomes of allogeneic HSCT for FA are improving steadily but remains suboptimal and often limited by donor availability- especially in countries lacking matched unrelated donor registry. For patients lacking a suitable donor, a trial of androgen is considered but is not curative, and around half of patients will not respond. Haploidentical HSCT has been successfully utilized in the management of acquired severe aplastic anemia and hematological malignancies but only limited published literature is available on its use in inherited bone marrow failure syndromes. We conducted this systematic review to explore survival outcomes of FA patients receiving haploidentical HSCT to assess feasibility of this treatment for patients lacking a matched donor. Methods We conducted a literature search on Pubmed, Cochrane, Google Scholar, open grey, and embase databases using the keywords; Haploidentical Transplant and Fanconi anemia. We screened 236 articles according to the Prisma diagram. After thoroughly reading the titles and abstracts, 13 articles were included for data extraction, and results were compiled. Results We analyzed thirteen studies with haploidentical transplant as a treatment for FA, 7 were retrospective, and 6 were prospective. Diagnosis of FA was established by chromosomal breakage analysis and genetic mutation testing. The preferred donor for a haploidentical transplant was a first-degree relative and mother/sibling in most cases. The total number of patients with FA and other disorder who received haploidentical transplants were n=340. The median age at HSCT was 6.7 (0.25-44) years. Two hundred six were male, and 134 were female. The most common conditioning regimen for FA patients was fludarabine, cyclophosphamide, and total body irradiation (TBI) followed by anti-thrombocyte globulin. Mehta. et al. evaluated haploidentical transplant without TBI in the conditioning regimen. The most common regimen to prevent graft versus host disease (GVHD) was cyclosporin and mycophenolate mofetil. Uppulur. R et al., Bonfim. C et al., Thakar. M.S et al. and Ayas, M et al. also used post-transplant cyclophosphamide for in vivo T cell depletion. Zubicaray. J et al and Strocchio. L et al. did not use any post-transplant therapy. Cumulative Overall survival reported was 79.1%. Cumulative acute GVHD was seen in 38.2%, while cumulative chronic GVHD was seen in 18.6% of patients. The most common adverse events were acute and chronic GVHD, Evans syndrome, steroid-induced osteoporosis, and diabetes. Respiratory syncytial virus, pneumonia, candida sepsis reactivation, hemorrhagic cystitis, and mucositis were the most common infections. Conclusion Fanconi anemia is an inherited bone marrow failure syndrome with somatic abnormalities and increased risk of hematological and solid organ malignancies. In FA, allogeneic hematopoietic cell transplantation (HCT) has been shown to restore normal hematopoiesis in patients with matched related donor HCT and has shown excellent long-term survival. Currently, limited data is available reporting outcomes of haploidentical HSCT for FA patients. More studies are required to establish safety and efficacy profiles. Figure 1 Figure 1. Disclosures Anwer: Allogene Therapeutics: Research Funding; GlaxoSmithKline: Research Funding; Janssen pharmaceutical: Honoraria, Research Funding; BMS / Celgene: Honoraria, Research Funding.

Acute Cerebral Infarction in a patient of Myelodysplastic Syndrome: A Case Report and literature review

Myelodysplastic syndrome (MDS) is a bone marrow failure syndrome characterized by cytopenia that results in infection and bleeding. However, there are few reports of cerebral infarction in MDS. In this case report we reported a Chinese female patient diagnosed MDS without drugs and an onset of acute cerebral infarction. Imaging examinations showed an ischemic stroke and further bone marrow aspiration identified MDS in the patient. Low dose aspirin and rehydration were used to improve symptom, as well as anti-epileptic drugs and rehabilitation. We also reviewed acute cerebral infarction associated with MDS from a total of three reported cases without drugs for the treatment of MDS. Our data provide further evidence that acute ischemic stroke might be associated with MDS, which may be due to complex chromosomal abnormality and inflammatory processes.

Lactic Acidosis in a Congenital Bone Marrow Failure Syndrome

Fifteen-month-old male child, known to have a congenital bone marrow failure syndrome, presented in a state of shock with severe lactic acidosis following a brief episode of vomiting. Hospital stay was complicated by recurrent bouts of metabolic acidosis and progressive hepatic failure. Blood mitochondrial DNA sequencing revealed a large heteroplasmic 4,977 bp mitochondrial deletion (approximately 40% of all mitochondrial copies) suggestive of Pearson marrow-pancreas syndrome. By virtue of natural disease course, within a month of admission child succumbed to end-stage liver failure with multi-organ failure and died.