Case Reports in Hematology最新文献

Down syndrome (DS) is defined by an extra copy of chromosome 21 and confers an increased susceptibility to hematological disorders. Transient abnormal myelopoiesis (TAM) and myeloid-leukemia associated with Down syndrome (ML-DS) are two conditions that need to be accurately diagnosed to provide appropriate management. Both TAM and ML-DS are characterized by proliferation of megakaryoblasts carrying a mutation in the GATA1 gene. Here, we report four cases with educational significance, highlighting typical diagnostic features that facilitate the differentiation between these two conditions, thereby assisting clinicians and medical laboratory professionals in effectively managing and monitoring these patients.

A delayed hemolytic transfusion reaction (DHTR) is a potential complication for patients with sickle cell disease (SCD) who develop red blood cell (RBC) alloimmunization to foreign antigens from allogeneic transfusions, potentially resulting in life-threatening hemolytic anemia between 24 hours and 28 days after the transfusion. Guidelines have suggested obtaining an extended RBC antigen profile by genotyping in patients with SCD to provide increased accuracy for antigen matching. We present a pediatric patient with SCD and a rare RBC phenotype that was not identified by serology who developed DHTR after her second lifetime transfusion and highlight the potential advantages of molecular genotyping. She was successfully managed by transfusion with "least incompatible" packed RBCs and aggressive medical management per American Society of Hematology clinical guidelines. Molecular genotyping is advantageous over serologic phenotyping because it can provide additional antigen information, such as increased accuracy for C antigen determination and Fy^b antigen matching. Having RBC genotyping results on file for patients with SCD can facilitate care in two ways-by preventing alloimmunization with potential hemolytic transfusion reaction and by responding rapidly to request rare donors when complicating antibodies arise.

EBV-positive primary nodal T-cell/NK cell lymphoma (TNKL) is a rare diagnosis with a poor prognosis. No relationship with follicular lymphoma (FL), classic Hodgkin lymphoma (cHL), or other non-Hodgkin lymphomas is established. We describe a case of Epstein-Barr virus (EBV)-positive cHL and EBV-positive primary nodal TNKL in the background of an antecedent FL, with all 3 subtypes identified in a single lymph node biopsy from an immunocompetent patient. Intensive frontline therapy achieved only a temporary response, with subsequent rapid progression associated with hemophagocytic lymphohistiocytosis (HLH). We discuss the relationship of the three lymphoma subtypes and the potential roles of EBV and immune dysregulation as contributing factors to this previously undescribed composite lymphoma.

Background: Lysine methyltransferase 2A (KMT2A) rearrangements are commonly found in juvenile acute myeloid leukaemia (AML). Although distinct diseases, there is a known clinical overlap between KMT2A-rearranged AML and juvenile myelomonocytic leukaemia (JMML). Both occur in infancy or early childhood and present with abnormal monocytosis. Case Report. We report a case of a 20-month-old girl, who presented with lethargy, recurrent infections, bruising, and marked hepatosplenomegaly. JMML was suspected after initial work-up, revealing an abnormal monocytosis without blast excess on immunophenotyping. The additional cytogenetic and molecular diagnostics, revealing a KMT2A rearrangement, was decisive for the confirmation of AML.

Conclusion: This case highlights the challenges of diagnosing KMT2A-rearranged monocytic AML and the importance of careful morphological assessment in partnership with cytogenetic and molecular diagnostics to distinguish between KMT2A-rearranged AML and JMML. Moreover, the emerging role of molecular monitoring in AML is highlighted.

Richter transformation (RT) is a rare sequelae of chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). The clonal relationship of the RT to the underlined CLL/SLL is an important prognostic factor as clonally related RT has a worse prognosis than that of clonally unrelated RT. The development of more than one RT in the same patient is exceedingly rare and prior reports have shown cases consisting of RT to diffuse large B-cell lymphoma (DLBCL) and a subsequent or synchronous Hodgkin lymphoma. Here, we present a rare case of RT first to a clonally unrelated DLBCL and subsequently a clonally related DLBCL. Additionally, we retrospectively conducted next-generation sequencing studies of both RT's and found different mutational landscapes, including more clinically aggressive mutations identified in the clonally related RT. To our knowledge, this is the first reported case of clonally related and clonally unrelated RT, both of which are DLBCL, in the same patient.

Isatuximab is an IgG1κ-derived monoclonal antibody against CD38 approved for the treatment of adult patients with multiple myeloma. Here we describe the successful treatment of a therapy-refractory pure red cell aplasia case following ABO-mismatched allogeneic stem cell transplantation with isatuximab. Our patient was a 75-year-old female with acute myeloid leukemia who received an HLA-B antigen mismatched, unrelated peripheral blood stem cell transplant with a major ABO incompatibility (blood group A+ in the donor and blood group O+ in the recipient). The patient developed persistent red cell aplasia and anti-A antibodies for more than 500 days from transplant. She received therapy with rituximab, bortezomib, prednisone, and darbepoetin alfa with partial to no response. After repeated insurance denials for daratumumab, isatuximab was obtained from the manufacturer through their CareASSIST program. Following the completion of 2 cycles of isatuximab (8 doses), significant and sustained red cell recovery was observed.

T-prolymphocytic leukaemia (T-PLL) is the most common mature T-cell leukaemia in Central Europe and is often manifested by rapidly increasing lymphocytosis, marked bone marrow infiltration and splenomegaly. In 10-15% of cases, the diagnosis is made by incidental findings in otherwise asymptomatic patients. Here we report a case of T-PLL that initially became symptomatic due to the presence of acute coronary syndrome (ACS). Initially, emergency coronary angiography with consecutive emergency 5-coronary artery bypass grafting (CABG) was performed. Leukocytosis was found perioperatively and T-PLL (with TCL1 rearrangement) was subsequently diagnosed. Despite known potential cardiotoxicity, the patient was treated with the anti-CD52 antibody alemtuzumab with a gradual dose increase from 3 mg to 30 mg per day. Systemic alemtuzumab therapy resulted in the complete remission of T-PLL in the bone marrow without any impairment to cardiac function. The patient was then eligible to undergo a consolidating allogeneic stem cell transplant (alloSCT). The reported case shows that T-PLL can also become initially symptomatic through an acute coronary syndrome on the basis of complex coronary heart disease. Targeted antileukaemic therapy with the monoclonal antibody alemzutumab can lead to effective systemic cytoreduction without cardiac dysfunction even in patients with severe cardiac disease, although cases of cardiotoxicity have been reported.

We present a patient at risk of misdiagnosis with multiple myeloma due to pseudohypercalcemia. Examinations showed monoclonal protein, 50% monoclonal plasma cells in bone marrow, and hypercalcemia but no osteolytic bone lesions. Follow-up tests revealed pseudohypercalcemia, with elevated total calcium, but normal ionized calcium: a discrepancy due to calcium binding to monoclonal paraprotein (confirmed by laboratory experiments). Accordingly, the patient was diagnosed with smouldering myeloma. After 900 days, the presence of bone lesions prompted the start of treatment for myeloma. Consequently, monoclonal paraprotein levels declined and pseudohypercalcemia dissolved. Hence, ionized calcium should be measured in monoclonal gammopathies to avoid misdiagnosis.

Chronic myeloid leukemia (CML) is associated with several breakpoint regions that result in different BCR::ABL1 fusion transcripts. These include the major breakpoint region (M-BCR), minor breakpoint region (m-BCR), and mu breakpoint region (u-BCR) corresponding to p210, p190, and p230 fusion transcripts, respectively. This patient is a 38-year-old female with a new diagnosis of CML in chronic phase. A novel p210 fusion transcript splice variant was detected with qualitative reverse transcription PCR and capillary electrophoresis. Subsequent FISH study was performed, which revealed 86.5% positive for the BCR::ABL1 fusion. Quantitative real-time polymerase chain reaction (PCR) showed a negative result for the p210 fusion transcript. The variant was further characterized by Sanger sequencing. This variant is in-frame and predicted to be functional. This case illustrates the need for a combination of different testing techniques to fully characterize the rare BCR::ABL1 fusion transcripts.

Dengue is a mosquito-borne, acute febrile illness caused by dengue viruses. The association between hematological malignancies and dengue infection is obscure, and the literature on this occurrence is also limited. We report two cases of acute leukaemia following dengue infection in a recent outbreak in Nepal. Our case reports suggest a possible association of acute leukaemia with dengue infection. The relationship should be explored further with observational studies.