Histocompatibility assessment in hematopoietic stem cell transplantation: recommendations from the Italian Association of Immunogenetics and Biology of Transplantation (Associazione Italiana di Immunogenetica e Biologia dei Trapianti - AIBT).

The outcome of allogeneic hematopoietic stem cell transplantation (HSCT) is significantly influenced by the degree of HLA histocompatibility between donor and recipient. To provide shared indications for required histocompatibility testing and interpretation before HSCT, the Italian Society for Immunogenetics and Transplantation Biology (Associazione Italiana di Immunogenetica e Biologia dei Trapianti [AIBT]) gathered members and created a working group to discuss and develop recommendations for histocompatibility assessment in HSCT.After a review of the literature and multiple panel discussions, AIBT developed up-to-date recommendations for the resolution levels of HLA typing, histocompatibility definitions of patients and donors, importance of anti-HLA antibodies, and significance of NK alloreactivity, which are reported in this document. These recommendations have been shared with the Italian Group for Bone Marrow Transplantation (Gruppo Italiano per il Trapianto di Midollo Osseo, cellule staminali emopoietiche e terapia cellulare [GITMO]) and the Italian National Center for Transplantation (Centro Nazionale Trapianti [CNT]). Notably, the increased use of HLA-mismatched transplantation (i.e., mismatched unrelated, haploidentical) in recent years has made these indications even more relevant for the standardization and improvement of quality of care.This document represents a useful instrument for health care workers involved in the field of HSCT, enhancing synergy with transplant physicians and enabling greater optimization of the available resources.

Use of DPB1 T-cell epitope algorithm among italian transplant centers: A survey on behalf of Associazione Italiana di Immunogenetica e Biologia dei Trapianti.

The HLA-DPB1 locus has been demonstrated to have a significant role on patients' outcome after allogeneic HSCT, and the so-called T-cell epitope (TCE) algorithm has been incorporated in international guidelines for the selection of unrelated donors. The purpose of the present study is to measure, through a national survey conducted on behalf of the Associazione Italiana di Immunogenetica e Biologia dei Trapianti (AIBT), the extent of awareness and use of HLA-DPB1 TCE-based algorithms during the donor search. 89% of the HLA laboratories answered to a short questionnaire and the results showed a progressive increase of the laboratories typing DPB1 in patients and their potential donors during the search (from 44% to 79% during the 2010-2019 period) as well as the application of a TCE-based algorithm for the donor choice whenever possible (from 24% to 65% during the same period). The DP-permissiveness status is detailed in the official HLA typing report by 12%, 32% and 50% of laboratories in 2010, 2015 and 2019, respectively. The present data indicate an encouraging raise in the awareness of the HLA-DPB1 role in unrelated donor selection; noteworthy, mentioning the TCE-based permissiveness status in the HLA typing report of each potential unrelated donor represents a notable mean to raise awareness among transplant physicians and to support them in their task of choosing the best donor. Nonetheless, despite the compelling evidence of the predictive ability of TCE-based algorithms, further efforts are still needed to extend its application to all transplant centers in Italy.

Transfusion-associated circulatory overload in gastroenterology.

BACKGROUND: Transfusion-associated circulatory overload (TACO) is a rare life-threatening event associated with transfusion. This study aimed to identify any case of TACO in a large cohort of highly transfused patients with gastrointestinal tract (GI) bleeding. MATERIALS AND METHODS: Data from patients who underwent an oesophago-gastro-duodenoscopy (OGD) were collected over one year from the gastroenterology service of a regional hospital. RESULTS: A total of 278 patients were identified, of which 81 required transfusion. In total, 811 blood components were transfused (red cell concentrate, platelets, plasma), leading to a cumulative TACO incidence of 12.3%. The probability of developing TACO was greater for patients aged ≥80 years (OR=3.9%; p=0.0058), with renal disease (OR=1.9%, p=not significant) and with cardiac disease (OR 11.1%; p=0.003). Patients with TACO had a lower overall survival (52 vs 20% at 3 years, p=0.034, HR=2.19, 95% CI: 1.04-4.63) compared to patients with cirrhosis without TACO (57 vs 28% at 3 years, p=0.003, HR=2.20, 95% CI: 1.30-3.72). Patients with an advanced stage of liver cirrhosis (Child Pugh c10 or more) were most likely to develop TACO. DISCUSSION: This study shows that within the GI setting TACO may be markedly under-reported. Clinical awareness for potential TACO development in GI patients with cardiac or renal disease or age >80 years is now required.

Effect of a liberal versus a restrictive pre-donation blood pressure policy on whole-blood donor adverse reactions.

BACKGROUND AND OBJECTIVES: The role of pre-donation blood pressure (BP) as independent contributor to post-donation vasovagal reactions (VVRs) is still debated. Differences between a liberal (i.e., inclusion of hypotensive donors) and a restrictive policy (i.e., not accepting hypotensive donors) should be investigated. This study aims to investigate the consequences of a liberal policy in development of VVRs after whole-blood donations. MATERIALS AND METHODS: We compared the incidence of VVRs between 2015 (restrictive policy) and 2016 (liberal policy) and the associated risk factors. We evaluated respectively 22 789 vs. 21 676 blood donations obtained from 18 001 blood donors (12 501 donated in both years). RESULTS: Comparing the results we obtained between 2015 and 2016, donations showed an overlap of the cohorts. Two hundred fifteen VVRs (incidence rate 0·48%) were observed, 104 (0·46%) of which in 2015, and 111 (0·51%) in 2016. A preliminary univariate analysis showed that donors with systolic BP <110 mm Hg had a two-fold risk of VVRs compared to normotensive donors (VVR/donation rate of 0·99% vs. 0·46%; P = 0·001). The subsequent multivariable logistic regression model showed that VVRs were highly associated with weight, site of collection, age and number of donations, excluding a role for systolic and diastolic BP. CONCLUSION: A liberal pre-donation BP policy seems to be safe for blood donors. Our analysis confirms that older donors with higher body-weight who already had donated blood are unlikely to experience VVRs.

Insight into the complex pathophysiology of sickle cell anaemia and possible treatment.

Sickle cell anaemia (SCA) is the consequence of abnormal haemoglobin production due to an inherited point mutation in the ß-globin gene. The resulting haemoglobin tetramer is poorly soluble when deoxygenated, and when this is prolonged, intracellular gelation of sickle haemoglobin occurs, followed by haemoglobin polymerisation. If many cycles of sickling and unsickling occur, the red cell membrane will be disrupted leading to haemolysis and vaso-occlusive events. Recent studies have also shown that leucocyte adhesion molecules and nitric oxide (NO) depletion are involved in endothelial damage. New insights in SCA pathophysiology and vascular biology have shown that cell-derived microparticle (MP) generation is also involved in the vaso-occlusion. Endothelial damage is perpetuated by impaired production or increased consumption of protective modulators such as protein C, protein S and NO. New therapeutic interventions should address these aspects of SCA pathogenesis. To date, the only US-FDA-approved therapy to prevent painful vaso-occulsive episodes is hydroxyurea that reduces haemoglobin polymerisation in sickle cells by increasing the production of foetal haemoglobin and L-glutamine. However, several new drugs have been tested in the last years in randomised clinical trials. We here report an update on the current status of knowledge on SCA.

Graft-versus-host disease (GvHD) of the tongue and of the oral cavity: a large retrospective study.

Graft-versus-host disease (GvHD) causes severe mucositis, impairs feeding and favors infection. The objective of this study was to identify the impact of GvHD in the oral cavity. We reviewed all consecutive patients who developed oral GvHD after HSCT. The study period was over 14 years. 53 patients were identified. M/F = 1.4; median age was 48.6 years; the median follow-up was for up to 3 years and 6 months. Conditioning regimens included several drugs (e.g., busulfan, cyclophosphamide and fludarabine). In 11 cases, radiotherapy (RT) was also used. Patients treated with RT were more likely to have tooth decay requiring fillings (p = 0.029), to need canal root interventions (p = 0.005) and to have tartar requiring oral hygiene interventions (p = 0.011). Patients with a lymphoma diagnosis were more likely to develop perioral scleroderma and chronic oral GvHD (cGvHD) (p = 0.045). Oral acute GvHD (aGvHD) was seen in 26 patients (49.1%). 21 (39.6%) patients developed cGvHD. GvHD of the tongue was seen in 21 (40%) patients. Oral mucositis was seen in only 5 patients (9.4%). Conditioning regimens with RT are more likely to induce oral aGvHD. The tongue is often affected by GvHD.

Intravascular large B-cell lymphoma associated with silicone breast implant, HLA-DRB1*11:01, and HLA-DQB1*03:01 manifesting as macrophage activation syndrome and with severe neurological symptoms: a case report.

BACKGROUND: Silicone implants have been successfully used for breast augmentation and reconstruction in millions of women worldwide. The reaction to the silicone implant is highly variable; it can lead to local inflammatory symptoms, and sometimes to systemic symptoms and disease. Over 80 cases of anaplastic lymphoma kinase-negative anaplastic large cell lymphoma have been reported in patients with silicone breast implants and have been accepted as a new clinical entity. To the best of our knowledge, an intravascular large B-cell lymphoma associated with a silicone breast implant has not been reported previously. CASE PRESENTATION: A 48-year-old Caucasian woman who presented with high fever was found to have splenomegaly on physical examination. A laboratory diagnosis revealed pancytopenia, hypertriglyceridemia, and hyperferritinemia. She developed signs of altered sensorium, hemiparesis, aphasia, and cauda equina syndrome. On further evaluation, she fulfilled the necessary five out of eight criteria for diagnosis of macrophage activation syndrome/hemophagocytic lymphohistiocytosis. Dexamethasone administration was followed by prompt improvement; however, 3 days later she again manifested high fever, which persisted despite administration of immunoglobulin and cyclosporine A. Her silicone breast implant was considered a possible contributor to her macrophage activation syndrome and was therefore removed. A histological examination of the capsule tissue showed an extensive lymphohistiocytic/giant cell foreign body reaction suggestive of autoimmune/inflammatory syndrome induced by adjuvants. However, the histological examination unexpectedly also revealed an intravascular large B-cell lymphoma. CONCLUSIONS: The genetic background of our patient with silicone breast implants might have predisposed her to three rare and difficult to diagnose syndromes/diseases: macrophage activation syndrome/hemophagocytic lymphohistiocytosis, autoimmune/inflammatory syndrome induced by adjuvants, and intravascular large B-cell lymphoma. The simultaneous manifestation of all three syndromes suggests causal interrelationships. Human leukocyte antigen testing in all women who undergo silicon breast implantation could in the future enable us to better evaluate the risk of potential side effects.

Post-transplant lymphoproliferative disease of donor origin, following haematopoietic stem cell transplantation in a patient with blastic plasmacytoid dendritic cell neoplasm.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is an extremely rare condition that originates from dendritic cells. We report on the first case of Epstein-Barr virus (EBV)-driven post-transplant lymphoproliferative disorder (PTLD) of donor origin in a BPDC patient post-allogeneic haematopoietic stem cell transplantation (HSCT). Flow cytometry study identified a cell population CD4+/CD56+/CD45RA+/CD123+/TCL1+ suggestive of BPDCN diagnosis, which was confirmed by a lymph node biopsy (cells positive for BCL11a, BDCA-2, CD2AP, CD123, TCL1 and S100). Cytogenetic analysis revealed a complex karyotype: (19 metaphase) 47,XX,t(1;6)(q21;q2?5),-13 + 2mar[11]/47, XX, +21 [3]/46,XX [5]. The patient was started on acute myeloid leukaemia (AML) induction schedule, and subsequently an allogeneic HSCT was performed. On day +36 post-HSCT, bone marrow biopsy/aspirate showed complete morphological remission, and chimerism study showed 100% donor chimera. However, on day +37, the patient was found to have enlarged cervical and supraclavicular lymphoadenopathy, splenomegaly and raised lactic dehydrogenase. EBV-DNA copies in blood were elevated, consistent with a lytic cycle. A lymph node biopsy showed EBV encoded RNA and large atypical B cells (CD45dim-, CD4+/CD56+, monoclonal for k-chain, CD19+/CD20+/CD21+/CD22+/CD38+/CD43+/CD79ß-/CD5-/CD10-), consistent with PTLD monomorphic type. Chimerism study showed that PTLD was of donor origin. This case together with the recent literature findings on BPDCN and PTLD are discussed.