Case Report: Acquired Haemophilia A Following mRNA-1273 Booster Vaccination Against SARS-CoV-2 With Concurrent Diagnosis of Pleomorphic Dermal Sarcoma.

While the global pandemic caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is still ongoing and new virus variants are emerging, there is a universal need for vaccines to protect individuals from severe complications and ideally control the pandemic by enabling herd immunity. Several vaccines against SARS-CoV-2 have been approved and are widely used to stem the recurring waves of coronavirus disease 2019 (COVID-19). Post-marketing surveillance is essential to record even rare safety issues related to these new vaccines. Among these issues, several autoimmune phenomena have been recorded in temporal association with and feasibly triggered by a vaccination. Acquired haemophilia A (AHA) is a rare condition characterized by new-onset haemorrhagic diathesis caused by an inhibitor of blood clotting factor VIII (FVIII), often in the elderly and most commonly associated with autoimmune or malignant disease. There have been a small number of AHA cases triggered by vaccinations, including those against SARS-CoV-2. We report the first case of AHA in temporal association with an mRNA-1273 booster vaccination. The diagnosis was made promptly, and the patient received appropriate care including immunosuppression using glucocorticoids, cyclophosphamide (CYC) and rituximab (RTX). The haemorrhage ceased after escalation of treatment, and the patient is recovering. Concurrent malignancy was initially ruled out using a wide scope of diagnostic tests, but pleomorphic dermal sarcoma (PDS) of the forehead occurred after initiation of specific AHA immunosuppressive treatment. Since large vaccination programs are ongoing worldwide and potential adverse events during post-marketing surveillance have been reported following vaccination against SARS-CoV-2, this case illustrates challenges in rare events occurring in association with SARS-CoV-2 vaccination and to proof a causal relationship. Therefore, there is an urgent need for reporting any events in association with SARS-CoV-2 vaccination, but also a crucial discussion about possible concurrent triggers and follow-up information about individual patients.

Patterns of Late Relapse after Allogeneic Hematopoietic Stem Cell Transplantation in Patients with T-Cell Prolymphocytic Leukemia.

Initial treatment with the monoclonal anti-CD52 antibody alemtuzumab induces responses in the majority of patients with T-cell prolymphocytic leukemia (T-PLL). In eligible patients, allogeneic hematopoietic stem cell transplantation (allo-HSCT) is an option to consolidate hematological remissions. Here, we report our experience with 10 patients who received allo-HSCT against T-PLL. Notably, 3 patients with complete remission at transplantation and durable full-donor chimerism relapsed at months 12, 59, and 84 after transplantation, respectively. This relapse was associated with rapid progressive leukemia in 1 patient and extralymphatic lymphoma growth in the other 2. Despite CD52 positivity at relapse, alemtuzumab retreatment, donor lymphocyte infusions, and/or chemotherapy including salvage therapy, allo-HSCT yielded a transient partial response, only. Alemtuzumab induction and consolidative allo-HSCT enabled prolonged disease-free survival in these patients but failed to procure cure.

Loss of donor chimerism in remission after allogeneic stem cell transplantation of T-prolymphocytic leukemia patients following alemtuzumab induction therapy.

T-cell prolymphocytic leukemia is a rare aggressive malignancy with low susceptibility to conventional chemotherapy. The anti-CD52 antibody alemtuzumab induces remission, which requires consolidation by stem cell transplantation in eligible patients. In this case series, three chemotherapy-naïve T-PLL patients received alemtuzumab for remission induction and allogeneic SCT after reduced-intensity conditioning. While primary hematopoietic engraftment occurred in a timely fashion, donor chimerism declined in all patients between day 28 and day 290 post-transplantation. Loss of chimerism was not associated with disease recurrence, and full chimerisms were regained on donor leukocyte infusion. In six B-CLL patients, treated with identical regimens of alemtuzumab and SCT, a similar pattern of failing chimerism was not observed. We surmise that an accumulation of uncleared alemtuzumab in the plasma may impede the incoming graft after allogeneic SCT, which would indicate the need for close monitoring and management of engraftment to secure complete donor chimerism and putative cure in T-PLL patients.