Journal of Hematology

Splenic B-cell leukemia/lymphoma with prominent nucleoli.

María Sol Neselis — 2026-05-28

Introduction
Splenic B-cell leukemia/lymphoma with prominent nucleoli is a recently defined mature B-cell neoplasm in the 2022 WHO classification (WHO-HAEM5), within the group of splenic B-cell lymphomas/leukemias. This entity arises in response to the limitations of the previous classification, in which diagnoses such as B-prolymphocytic leukemia (B-PLL) and the variant of hairy cell leukemia (HCL-v) showed significant clinical, morphological, and immunophenotypic overlap.¹

Clinical case
A 57-year-old patient with a history of smoking presented with a three-month history characterized by asthenia, adynamia, and diffuse abdominal pain. Evaluation revealed leukocytosis and marked splenomegaly. Laboratory results: Hct 20.5%; Hb 4.5 g/dL; leukocytes 496,000/mm³; platelets 52,000/mm³. LDH 595 IU/L.

Peripheral blood smear showed leukocytosis predominantly composed of medium-to-large cells, with a high nucleus-to-cytoplasm ratio due to nuclear predominance, loose chromatin, and a central nucleolus. Cytoplasm was scant to moderate, weakly basophilic, without evident granules. Cellular shadows (Gumprecht type) were present but not predominant. Mild to moderate anisocytosis. Thrombocytopenia. (Figure 1).

A whole-body CT scan (PanCT) demonstrated hepatomegaly and splenomegaly measuring 245 × 122 mm, with adenomegalies (8 mm) at the left axillary and inguinal levels.

Peripheral blood flow cytometry: 85.7% clonal B lymphocytes. Medium-sized cells: CD45++, CD19++, CD34(-), CD20++, CD38(-), CD5(-), CD10(-), CD23(-), CD79b+, CD200(-), CD43(-), CD31+, CD305++, CD11c(-), IgM(-), CD81++, CD62L+, CD95(-), with surface immunoglobulin light chain restriction (kappa).

Bone marrow biopsy: bone marrow infiltration (85%) by small B-cell lymphoma, CD20 positive. CD3: negative. CD10: negative. CD15: negative. CD30: negative. CD34: negative. CD45: positive. BCL6: negative. BCL2: positive. MUM1: negative. Ki67: 10% positive.

Molecular biology: TP53 mutated. CNS evaluation by flow cytometry showed involvement (53% clonal B lymphocytes with the same phenotype). Treatment with ibrutinib was initiated, and the patient is currently in complete remission.

Conclusion
Splenic B-cell neoplasms with prominent nucleoli represent a diagnostic challenge. In this case, diagnostic suspicion was supported by the concordance between clinical findings, cytomorphology, and flow cytometry (with absence of characteristic markers: CD5-, CD10-, CD23-), allowing the case to be oriented toward this entity despite the lack of a defining marker, highlighting the importance of an integrative approach for an accurate diagnosis.

Visceral leishmaniasis: role of the hematologist in the early diagnosis.

María Fernanda González Hobecker — 2026-05-28

Three clinical cases of visceral leishmaniasis diagnosed in the province of Misiones, Argentina, are presented. The patients presented with febrile syndrome, cytopenias and hepatosplenomegaly. Their clinical evolution, diagnostic workup, including serological and parasitological methods, bone marrow examination and treatment are specified. The importance of considering this disease in the differential diagnosis of febrile syndromes with hematological abnormalities and organomegaly in endemic areas is highlighted, and the role of the hematology team in its suspicion and confirmation is emphasized.

Bone marrow changes in a case of Wilson’s disease- A Case report

Drishti Sachan — 2026-05-28

Background: Wilson’s disease is a rare autosomal recessive disorder of copper metabolism caused by mutation of ATP7B gene on chromosome 13 resulting in excess accumulation of free copper in the liver, brain and eyes. Case presentation: We describe the case of a twelve year old boy with Wilson’s disease who developed bicytopenia. Bone marrow aspirate and biopsy was subsequently performed and the findings were observed. Informed consent was taken from the patient before the procedure. Conclusion: Bone marrow aspirate and biopsy revealed drug induced suppression of bone marrow. Myeloid, erythroid and megakaryocyte series showed perinuclear vacuolization along with abnormal pigment deposition in myeloid precursors. Close monitoring of hematological parameters is required while the patient is on treatment.

MECOM-associated syndrome presenting as severe bone marrow failure without skeletal abnormalities: a distinct clinical variant. Case report.

Erika Jhohanna Arenas Contreras — 2026-05-28

The MECOM-associated syndrome encompasses a spectrum of hematologic and skeletal abnormalities, with severe bone marrow failure being one of its main manifestations. The case of a seven-month-old male infant, presenting at two months of age with severe pancytopenia, is described. Bone marrow studies revealed hypocellularity with poor hematopoietic representation and hypolobulated megakaryocytes, with a normal karyotype (46,XY). Clinical exome sequencing identified a novel heterozygous variant in the MECOM gene, classified as likely pathogenic. Radiographs ruled out radioulnar synostosis or other skeletal abnormalities, thereby expanding the geno-phenotypic spectrum of MECOM variants.

Keywords: MECOM, bone marrow failure, pancytopenia, aplastic anemia.

CAR-T cell therapy in lymphomas.

Ana Lisa Basquiera — 2026-05-28

Chimeric antigen receptor T-cell (CAR-T) therapy has profoundly transformed the therapeutic landscape of B cell lymphomas, particularly in relapsed and refractory settings. Built upon decades of advances in immunology, molecular biology, and gene therapy, CAR T cells enable major histocompatibility complex–independent tumor recognition and potent antitumor immune responses. This review summarizes the historical development of CAR-T therapy, key aspects of manufacturing and quality control, approved indications, clinical outcomes, treatment related toxicities, and emerging innovations in the field. Second generation anti CD19 CAR T products have demonstrated unprecedented response rates and durable remissions across multiple subtypes of B cell non Hodgkin lymphomas, including diffuse large B cell lymphoma, follicular lymphoma, and mantle cell lymphoma, leading to regulatory approvals in several disease settings and earlier lines of therapy. Despite these successes, CAR T therapy remains associated with unique toxicities such as cytokine release syndrome, immune effector cell–associated neurotoxicity, prolonged cytopenias, and infectious complications, requiring specialized multidisciplinary management. Rapid advances in CAR T engineering and manufacturing are now addressing key biological and logistical limitations. Innovations such as ultra rapid manufacturing platforms, dual targeted CAR constructs, and allogeneic “off the shelf ” products aim to improve cellular fitness, reduce antigen escape, enhance accessibility, and shorten vein to vein time. As CAR T therapy continues to evolve toward earlier disease settings and broader global implementation, coordinated efforts in regulatory frameworks, infrastructure development, toxicity management, and sustainable financing will be essential to maximize its impact on patient outcomes.

ADAMTS13 activity measurement by chemiluminescence method

Marina Sol Lopez — 2026-05-28

ADAMTS13 es una metaloproteinasa, específicamente una desintegrina, que presenta un motivo trombospondina tipo 1 miembro 13. Es la proteasa del factor de von Willebrand (VWF), ya que es responsable de clivar al factor en multímeros de menor tamaño y de intervenir en la regulación de su actividad(1). La deficiencia de ADAMTS13 lleva al aumento de multímeros ultra grandes del factor de von Willebrand, causa de la púrpura trombocitopénica trombótica (PTT)(2), debido a que estos multímeros son altamente trombogénicos. La PTT es una microangiopatía trombótica rara caracterizada por anemia hemolítica mecánica, trombocitopenia por consumo y otros síntomas generados por el daño isquémico de órganos terminales causado por trombosis microvascular, presentando una actividad de ADAMTS13 menor al 10%(3), por lo que la medición de la actividad de esta proteasa es de suma importancia para el diagnóstico de esta enfermedad.

Evaluation of the main causes of clinical ineligibility for blood donation in Belo Horizonte: a retrospective analysis

JG Brant Rocha — 2026-04-30

Background. Although rigorous donor selection is essential to blood safety, the deferral process can have negative impacts on the blood supply. Many deferred donors do not return, often due to negative feelings associated with being deferred. Deferral rates and the reasons for deferral vary across different blood centers. An understanding of these deferral rates and underlying reasons can help in designing more effective recruitment strategies and alleviate blood shortages, which are critical for the treatment of many patients. Objective. This study aimed to investigate the rates and reasons for donor deferral. Methods. A retrospective study (2019-2022) was conducted at a homonucleus. Donor deferrals were analyzed based on demographic characteristics. Results. Among 98827 candidates, 18974 (19,16%) were deferred. Temporary deferrals accounted for (88,8%), permanent for 8,20%, and withdrawals for 2,74%. The most prevalent causes were divided into the following groups: HIV/hepatitis-related risk factors (38,9%), general ineligibility (22,1%), medical conditions (14,6%), medication use (12,9%), and other infection risks (11,3%).

What should hematologists know about the certification and periodic revalidation of the hematology specialist certificate?

Marta Zerga — 2026-04-30

Initial certification in Hematology confirms that the physician has acquired sufficient practical and theoretical knowledge to be recognized as a specialist in Hematology. This initial certification is valid for five years, after which it must be maintained. This maintenance process involves upholding and enhancing professional competencies. Certification renewal (formerly called recertificaction) is the procedure by which hematologists submit, every five years, a detailed account of their activities in both clinical and academic settings, broken down annually. The certification and the periodic revalidation renewal of hematologists are the processes that ensure the quality of medical care and, therefore, patient safety. The Council for the Certification of Medical Professionals (CCPM) of the National Academy of Medicine was created with the primary objective of establishing an autonomous structure responsible for the voluntary certification of professionals and its revalidation, thereby guaranteeing the quality of medical care for the population through certified and revalidated physicians. In 1994, the Argentine Society of Hematology (SAH) joined the CCPM as an accredited scientific society. Both the SAH and the CCPM encourage practicing professionals to voluntarily undergo periodic evaluation based on their background and professional and academic performance, demonstrating their commitment to continuous improvement and professional development.

Experience of people with severe hemophilia and their caregivers in Argentina.

Alejandra Baques — 2026-05-28

Introduction. Hemophilia is a hereditary bleeding disorder that significantly affects the quality of life of patients and their caregivers. Methods. This study assessed the experiences of people with hemophilia and their caregivers in Argentina through an online survey and a face-to-face discussion. A total of 12 participants (7 patients and 5 caregivers) from different regions of the country were included. Key aspects such as diagnosis, treatment access, therapy adherence, emotional impact, and quality of life were analyzed. Results. Delays in diagnosis were identified, as well as barriers to medication access, and challenges in treatment adherence, influenced by treatment burden and lack of information on new therapies. One-third of participants reported frequent pain and recurrent bleeding episodes. Despite overall treatment acceptance, issues were identified regarding shared decision-making and the availability of emotional support. Discussion. These findings highlight the need to improve medical education, optimize medication access, and strengthen psychological and social support for people with hemophilia in Argentina.

Hematological and morphological alterations in blood donation applicants.

P Aro — 2026-04-30

Introduction. Complete blood counts and blood smears are complementary tests that together provide a comprehensive blood assessment and can contribute significantly to the detection of abnormalities in blood donation applicants. The objective of the study was to describe hematological and morphological alterations in blood donation applicants. Materials and methods. Cross-sectional study conducted at the Hemotherapy Service and Blood Bank of the Cayetano Heredia National Hospital during the month of December 2024. Complete blood counts and blood smears were examined in 124 blood donation applicants to determine their hematological profile and morphology, respectively. Descriptive statistics were used to present the results. Results. 77,8% of applicants were male. The frequency of hematological abnormalities identified by blood count was 33,9%, while by blood smear it was 53,2%. The most frequent abnormalities in the blood count were monocytosis (11,6%), macrocytosis (9,7%), and anisocytosis (7,3%). In the blood smear, the main abnormalities observed were anisocytosis (23,4%), neutrophil hypersegmentation (21,7%), toxic granulations (10,8%), macrocytosis (10,5%), and platelet aggregates (6,4%). Conclusions. Hematological abnormalities are common among prospective blood donors. A blood smear, used in conjunction with a complete blood count, could provide additional information in the evaluation of prospective blood donors. However, its impact on donor selection should be assessed in future studies.

Bridging the CART gap: epcoritamab as a feasible option for relapsed/refractory DLBCL in CART-inaccessible regions - “the Argentine experience”

Carolina Mahuad — 2026-05-28

Introduction. In the absence of CART, bispecific antibodies (BsAbs) emerged as a potential alternative for RR patients. BsAbs can offer a bridge to consolidation strategies (autologous/allogeneic-stem cell transplant (ASCT/Allo-SCT)). This study evaluated the utilization of epcoritamab in compassionate use requests before its approval in Argentina; assessed response rates, PFS, and overall survival (OS) in patients treated with epcoritamab, and compared outcomes in those who received consolidation therapies. Methods. 40 patients with RR-DLBCL who requested epcoritamab through the compassionate use program in Argentina were included. 28 patients were analyzed. 7 patients did not receive treatment due to disease progression. Data for 5 were not available. Results. 89% was diagnosed with DLBCL, predominantly NOS. Mean age was 57 ± 11 years. Most patients had advanced-stage disease (III/IV), many showing extranodal involvement. The mean of previous lines was 3 (range 2-5, including ASCT 29.6%). Patients received 1-15 cycles (C) of E (median 4.5), and 26/28 underwent PET-CT after C2 of E;19 showed response (CR/PR). 26/28 responded:15 achieving CR,8 before C4. Epcoritamab was used as a bridge to ASCT or Allo-SCT in 5 patients, with an OS rate of 100% among those who received Allo-SCT. The OS for all patients was 46.2% at 12.5 months. The OS increased to 66.7% at 12 months among responders, significantly higher than the 20% OS in non-responders. At 18 months of follow-up, OS was 50% and 0%, respectively. Consolidation with Allo-SCT resulted in an OS of 100% (p = 0.01), although the number of patients receiving ASCT was too small to make a meaningful comparison. Response to epcoritamab was independent of sex, number of prior treatments, or primary refractory status, but responders had significantly better survival outcomes (p=0.003). No significant association was found between response and the presence of cytokine release syndrome (CRS) or immune effector cell-associated neurotoxicity syndrome (ICANS), though ICANS was linked to an increased risk of death (p=0.03). Regarding safety,39% of patients had CRS (most G1), and 18% had ICANS. 9 patients developed cytopenias, mostly mild, and 13 developed hypogammaglobulinemia. The mortality rate was 53.6%(disease progression (8/28), infections (6/28)). Hypogammaglobulinemia significantly increased the risk of death (p=0.001), and cytopenias showed near-statistical significance (p=0.05). Conclusion. The study’s cohort characteristics were similar to the EPCORE NHL-1 study, with the notable exception of no prior CART exposure. Epcoritamab demonstrated efficacy comparable to other studies, with encouraging survival outcomes in patients who responded to treatment. It also highlighted the potential of BsAbs as a bridge to consolidation with ASCT or Allo-SCT, achieving a 100% survival rate for those who received Allo-SCT. The use of BsAbs as a bridge to consolidation (mean 4 cycles) is a viable non-standard option for countries where their high costs make them unaffordable. Proper management of adverse events such as infections and hypogammaglobulinemia is crucial for improving safety and survival outcomes in these high-risk patients.

Reticulocytic hemoglobin behavior and its usefulness in differentiating thalassemia syndromes from iron deficiency in pediatrics.

Karina Bartolome — 2026-05-28

Introduction. Iron deficiency anemia and thalassemic syndromes represent the main causes of microcytic hypochromic anemia in pediatrics and share hematimetric features that make their initial diagnostic differentiation difficult. Reticulocyte hemoglobin content (RET-He) allows evaluation of hemoglobinization in recent erythropoiesis. This study has as its objective to assess the usefulness of RET-He in differentiating thalassemic syndromes from iron deficiency in pediatrics and to establish an optimal cutoff value. Materials and methods. A retrospective, cross-sectional, analytical observational study was conducted in patients aged 1 to 15 years between 2019 and 2024. Hematological parameters, iron metabolism studies, hemoglobin electrophoresis, and molecular studies for alpha thalassemia were analyzed. Patients were classified into four groups: iron deficiency anemia, iron deficiency without anemia, beta thalassemia and alpha thalassemia. Non-parametric tests and ROC curve analysis were performed. Results. RET-He showed statistically significant differences between the beta thalassemia group and the other groups (p < 0.05). ROC analysis identified a cutoff value of ≤ 22.8 pg, with 100% sensitivity and 100% specificity for discriminating beta thalassemia from alpha thalassemia and iron deficiency without anemia, and a specificity of 61% when compared with iron deficiency anemia. Discussion. RET-He is a useful parameter for differentiating beta thalassemia from other microcytic conditions, particularly with a high negative predictive value.

Is it possible to reduce the dose of tyrosine kinase inhibitors and maintain response in chronic-phase Philadelphia chromosome– positive chronic myeloid leukemia? A single-center experience.

Julieta D'antuoni — 2026-05-28

Introduction. Since the introduction of tyrosine kinase inhibitors (TKIs) in 2001, chronic myeloid leukemia (CML) has become a chronic disease, with survival comparable to that of the general population. This entails lifelong treatment and prolonged exposure to long-term toxicities. Although the current goal is treatment discontinuation after achieving sustained deep responses over a defined period, fewer than 50% of patients achieve this outcome, while the remainder require long-term therapy. Therefore, strategies such as dose reduction (DR) are essential to mitigate adverse events (AEs). Prospective evidence remains limited. Materials and Methods: An analytical, retrospective cohort study was conducted. Patients aged ≥18 years with a diagnosis of chronic-phase chronic myeloid leukemia (CML-CP) who required tyrosine kinase inhibitor (TKI) dose reduction (DR) due to adverse events (AEs), intolerance, or other causes were included between 2001 and 2024 at a single center in the City of Buenos Aires. Results: Out of 329 patients with CP-CML, 25 who required TKI dose reduction during treatment were included. Eighty percent (20/25) reduced the dose due to toxicity. In the remaining cases, dose reduction was performed in the context of achieving a major molecular response (MMR) or deeper responses, according to physician judgment. Among the 21 patients who initiated DR with MMR or achieved it during the process, MMR loss-free survival (MMRLFS) at 24 months was 85%, increasing to 94% in the subgroup of 16 patients who had already achieved MMR at the time of DR initiation. In terms of safety, the AEs leading to dose adjustment completely resolved in 17 patients (68%). Discussion: In this study, TKI dose reduction appears to be a safe strategy that maintains response in most patients—particularly in those with prior MMR—and reduces toxicity in the majority of cases. This approach improves quality of life and adherence without compromising efficacy. In cases of response loss, re-escalation to the standard dose generally allows recovery of MMR.

Hemophagocytic lymphohistiocytosis in pediatrics: diagnostic and therapeutic challenges in a tertiary hospital in Guayaquil, Ecuador.

Andrés Roberto González Cabrera — 2026-05-28

In pediatrics, the secondary form is the most prevalent and is usually triggered by infections, malignancies, or autoimmune diseases. Due to its rapid progression and high mortality rate, early diagnosis is crucial for survival. Objective. To describe the clinical characteristics, laboratory findings, etiology, treatment, and outcomes of pediatric patients with HLH at a tertiary care hospital in Guayaquil, Ecuador. Materials and methods. A descriptive and retrospective study of a series of 22 cases (January 2019–September 2025) diagnosed according to the HLH-2004 criteria. Demographic variables, paraclinical findings, bone marrow studies, infectious triggers, and treatment protocols were analyzed. Results. The mean age was 4.26 years. Fever was universal (100%), and splenomegaly affected 86.36% of patients. Universal hyperferritinemia (mean: 8,804 ng/mL) and hypofibrinogenemia were observed in 86.36% of cases. Viral infections were the main trigger (86.36%), with dengue and SARS-CoV-2 being the most prevalent (40.91% each), along with a high incidence of multisystem inflammatory syndrome (MIS-C) in 54.55%. Treatment included dexamethasone (90.91%), immunoglobulin (54.55%), and etoposide (18.18%). Mortality was 22.73%. Discussion. Pediatric HLH presents with high morbidity and is frequently associated with endemic and emerging viruses in the region. Diagnosis based on biomarkers such as ferritin is crucial, especially in severe cases of dengue or MIS-C, to initiate aggressive immunosuppressive therapy.

30 Years of the Hematology Journal

José Ceresetto — 2026-04-30