Parvovirus B19 (PVB19) infection is a recognized cause of transient bone marrow suppression and pure red cell aplasia; however, pancytopenia with hypocellular marrow and multilineage dysplasia is uncommon in children and poses a diagnostic challenge. We report the case of a previously healthy 7-year-old girl who presented with pancytopenia during acute PVB19 infection, confirmed by high viral loads in peripheral blood, cerebrospinal fluid, and bone marrow. Initial bone marrow examination demonstrated hypocellularity with multilineage dysplasia but did not meet criteria for myelodysplastic syndrome. Comprehensive evaluation excluded autoimmune disease, primary immunodeficiency, inherited bone marrow failure syndromes, and known pediatric MDS predisposition genes. Serial follow-up revealed persistent hypocellularity and evolving dysplasia, ultimately establishing the diagnosis of childhood MDS with low blasts (cMDS-LB). The patient underwent successful allogeneic hematopoietic stem cell transplantation with stable full donor chimerism and hematologic recovery. Post-transplant, she experienced episodes of febrile pneumonitis accompanied by transient increases in PVB19 DNA levels, followed by a gradual decline with persistent low-level PVB19 DNAemia at last follow-up (day +618). This case highlights that PVB19 infection may temporally coincide with, reveal, or contribute to an evolving pediatric myelodysplastic process rather than directly causing it.

Systemic mastocytosis is a rare clonal disease that leads to the abnormal growth and accumulation of mast cells in different organs. Clinical presentation varies from indolent disease to aggressive multiorgan involvement. Portal hypertension due to hepatic infiltration is not common, and this presentation with upper gastrointestinal bleeding is extremely rare, especially in young patients. We present a case report of a 21-year-old female with melena, generalized weakness, and dizziness. On examination, massive splenomegaly was noted. Laboratory tests revealed pancytopenia, and ultrasonography and contrast-enhanced CT of the abdomen revealed features of portal hypertension without cirrhosis. Upper gastrointestinal endoscopy showed esophageal varices. Systemic mastocytosis was diagnosed by bone marrow examination, which revealed dense aggregates of abnormal spindle-shaped mast cells, followed by immunohistochemistry of the samples, which were positive for CD117 and CD25. Management of the patient included supportive care such as blood transfusions and endoscopic therapy for variceal bleeding. This case demonstrates a very rare and severe manifestation of systemic mastocytosis in a young patient, and highlights the importance of considering infiltrative hematological disorders in non-cirrhotic portal hypertension presenting with unexplained cytopenias.

Visceral leishmaniasis (VL) is a systemic parasitic disease that predominantly involves the reticuloendothelial system, with pulmonary involvement being distinctly uncommon, particularly in individuals who are immunocompetent. We report a case of a middle-aged female who was immunocompetent presenting with acute hypoxaemic respiratory failure, characterised by progressive dyspnoea, bilateral lung consolidation and pleural effusion, initially mimicking severe pulmonary infection or haematological malignancy. The presence of pancytopenia, hypergammaglobulinaemia and massive hepatosplenomegaly raised suspicion of an underlying systemic disorder. Definitive diagnosis was established by demonstration of Leishmania donovani amastigotes in splenic aspirate, with further confirmation of direct pulmonary involvement through identification of intracellular amastigotes within alveolar macrophages on a transbronchial lung biopsy. The patient showed significant clinical and radiological improvement following treatment with liposomal amphotericin B and miltefosine. This case highlights that VL can rarely present with primary pulmonary manifestations even in immunocompetent hosts. It underscores the importance of considering VL in the differential diagnosis of unexplained pulmonary infiltrates with systemic features in endemic regions and demonstrates that histopathological confirmation from lung tissue can be crucial in establishing pulmonary involvement in atypical presentations.

Acute promyelocytic leukaemia (APL) is a subtype of acute myeloid leukaemia characterised by the PML-RARα fusion gene and a high risk of early mortality if treatment is delayed. Gingival hypertrophy is an uncommon manifestation of APL and is more typically associated with monocytic and myelomonocytic AML. We report a 26-year-old male who presented with a three-week history of progressive gingival enlargement, initially managed as gingivitis for two weeks, resulting in delayed haematological evaluation. Microgranular APL was confirmed by bone marrow morphology and fluorescence in situ hybridisation, demonstrating t(15;17). Although pancytopenia was present, the absence of hyperleukocytosis or overt coagulopathy contributed to an atypical clinical picture. Due to resource constraints, all-trans retinoic acid-based therapy was unavailable, and induction chemotherapy was administered, with a fatal outcome after one week. This case highlights gingival hypertrophy as an atypical early presentation and the impact of delayed diagnosis and limited access to essential therapy.

Biallelic variants in the neuroblastoma amplified sequence (NBAS) gene have been associated with short stature, optic atrophy, and Pelger-Huët anomaly (SOPH) syndrome, infantile liver failure syndrome type 2 (ILFS-2), and an increasingly broad spectrum of clinical phenotypes. However, cases presenting with hemophagocytic lymphohistiocytosis (HLH) accompanied by immune dysfunction and multisystem involvement have not been reported. We identified novel compound heterozygous variants in the NBAS gene, c.5139-5T>G and c.5983C>T, in a Chinese girl who successively developed recurrent infections, short stature, ILFS-2, progressive cytopenias from leukopenia to bicytopenia and eventually pancytopenia, and HLH. Polymerase chain reaction confirmed that c.5139-5T>G variant caused aberrant splicing. The c.5983C>T variant is novel and was classified as likely pathogenic according to American College of Medical Genetics and Genomics guidelines. Western blotting of the patient's PBMCs detected only a truncated NBAS protein, consistent with the product predicted from the c.5983C>T variant. Functional studies in HEK293T cells overexpressing the truncated NBAS protein further indicated impaired NBAS function, as assessed by real-time quantitative reverse transcription polymerase chain reaction and immunofluorescence analysis. We systematically reviewed 322 previously reported patients and analyzed genotype-phenotype correlations in 316 cases to further define the clinical spectrum of NBAS-related disease. We identified a novel pathogenic NBAS variant, further expanded the phenotypic spectrum of NBAS-related disease, and provided additional insight into genotype-phenotype correlations. Pancytopenia and HLH may reflect severe immune dysregulation and poor prognosis, highlighting the importance of early recognition and timely intervention.

Acute myeloid leukemia (AML) in patients with end-stage renal disease (ESRD) requiring hemodialysis presents numerous challenges to clinicians, including selection of appropriate chemotherapy agents, safe dose adjustment, and supportive care management. Due to the lack of prospective studies in patients undergoing dialysis, it is difficult to determine the optimal therapeutic approach for this population. These patients are commonly excluded from large-scale AML clinical trials, which further complicates the determination of effective management strategies and associated toxicities. We present the case of a 51-year-old man with ESRD on hemodialysis who developed an adverse-risk AML (characterized by a BCL6 corepressor (BCOR) mutation with runt-related transcription factor 1 (RUNX1) and nuclear receptor-binding SET domain protein 1 (NSD1) abnormalities). Initial presentation was notable for profound pancytopenia without circulating blasts, although peripheral blood flow cytometry confirmed AML. Management required a multidisciplinary discussion with leukemia specialists, nephrology, and pharmacy. The patient was treated with azacitidine and venetoclax rather than intensive induction chemotherapy because of dialysis dependence, cardiovascular comorbidities, and anticipated toxicity. Azacitidine was administered after dialysis sessions, while venetoclax dosing was adjusted because of concomitant posaconazole prophylaxis. Repeat molecular testing no longer detected previously identified BCOR and RUNX1 abnormalities, although a persistent NSD1 variant remained detectable, and molecular remission could not be confirmed. Treatment was successfully continued through 12 cycles without clinically significant tumor lysis syndrome. Approximately one year after diagnosis, relapsed AML was identified on peripheral blood flow cytometry. This case highlights the feasibility of venetoclax-based lower-intensity therapy in selected dialysis-dependent AML patients while underscoring the persistent therapeutic limitations and adverse prognosis associated with relapsed disease in this population.

Methotrexate (MTX) is a folate antagonist widely used as a disease-modifying antirheumatic drug (DMARD) in rheumatoid arthritis (RA), as well as in several malignancies and autoimmune disorders. Although low-dose MTX (5-20 mg/week) is generally considered safe, it has a narrow therapeutic index, and toxicity can occur even at therapeutic doses, particularly in high-risk patients. We describe a 58 year-old man with RA and chronic kidney disease (CKD) who presented with gastrointestinal symptoms, neurologic impairment, and a papulopustular rash. Laboratory evaluation revealed pancytopenia and acute kidney injury (AKI) superimposed on CKD. Despite a normal serum MTX level, clinical findings strongly suggested MTX toxicity. The patient received emergent hemodialysis, leucovorin rescue therapy, hematologic support, and intensive care management. Extensive investigations excluded alternative hematologic, infectious, and systemic causes. His clinical course was complicated by acute pancreatitis, and he ultimately died. This case emphasizes that serum MTX levels may not reliably predict toxicity in high-risk patients and underscores the importance of recognizing clinical signs and symptoms, promptly identifying early manifestations, discontinuing MTX, and initiating leucovorin rescue therapy.

Extrahepatic portal venous obstruction (EHPVO) is a leading cause of prehepatic portal hypertension in children, particularly in developing countries. While upper gastrointestinal bleeding is the most common presentation, EHPVO may rarely manifest predominantly with hematological abnormalities due to hypersplenism, posing a diagnostic challenge and mimicking primary bone marrow disorders. We report a 13-year-old female child who presented with pancytopenia, splenomegaly, and easy fatigability, without a history of gastrointestinal bleeding or liver disease. Initial evaluation suggested a primary hematologic disorder, and bone marrow aspiration revealed a hypocellular marrow without malignant infiltration. Extensive workup excluded nutritional, infectious, autoimmune, and malignant causes of pancytopenia. Subsequent abdominal imaging demonstrated non-visualization of the main portal vein with multiple periportal collateral vessels and hepatopetal flow, consistent with cavernous transformation of the portal vein secondary to chronic extrahepatic portal venous obstruction. Upper gastrointestinal endoscopy revealed grade III esophageal varices, which were managed with endoscopic variceal ligation and initiation of non-selective beta-blockers. This case illustrates an uncommon but clinically important presentation of pediatric EHPVO, in which hypersplenism leads to pancytopenia and secondary bone marrow suppression, closely mimicking primary marrow failure. Recognition of this pattern is crucial to avoid misdiagnosis and unnecessary investigations. Imaging, particularly Doppler ultrasonography, plays a pivotal role in establishing the diagnosis. EHPVO should be considered in the differential diagnosis of pancytopenia with splenomegaly in children, even in the absence of overt gastrointestinal bleeding. Early recognition through appropriate imaging can guide timely management and prevent complications of portal hypertension.