Vitamin B12 Deficiency Manifesting As Pancytopenia, Lymphadenopathy, and Fever: A Clinical Mimic of Hematologic Malignancies.

Pancytopenia is a complex medical condition characterized by decreased levels of red blood cells (RBCs), white blood cells (WBCs), and platelets (PLTs). It can arise from impaired production, peripheral destruction, or a combination of both. The causes of pancytopenia range from reversible factors like infections and medication reactions to irreversible conditions. Vitamin B12 deficiency is a notable reversible cause that can take years to manifest in adults due to stored reserves. However, deficiencies caused by impaired absorption, especially due to the lack of intrinsic factors (IFs), can lead to rapid deterioration within two to five years. A healthy 39-year-old male with an athletic lifestyle presented with symptoms such as dizziness, nausea, vomiting, palpitations, and fainting over a few days. These symptoms were preceded by weeks of persistent body aches, headaches, weakness, daily fevers, chills, and night sweats. Vital signs were stable. The physical examination revealed conjunctival pallor and lymphadenopathy in the submandibular and superficial cervical regions. Initial blood tests showed normocytic anemia (Hgb 4.9, MCV 80), leukopenia (2.99), thrombocytopenia (142), and elevated liver enzymes (AST 199, ALT 96, and total bilirubin of 2.04). The peripheral smear showed tear-drop cells and hypochromic cells. The initial impression was hematologic malignancy, including but not limited to leukemia, lymphoma, or myelofibrosis given clinical findings such as B-symptoms like night sweats, neck lymphadenopathy, and subjective daily fever, along with pancytopenia. The patient received a bolus of normal saline and a transfusion of two units of packed RBCs. CT scans of the chest, abdomen, and pelvis showed no adenopathy or splenomegaly. Although initial clinical assessment pointed toward a potential hematologic malignancy, comprehensive testing, including SPEP, reticulocyte count/fraction, serum folate, and serum vitamin B12, revealed only severe vitamin B12 deficiency, with a level of less than 150, with the presence of IF antibodies. Treatment involved intensive in-patient vitamin B12 injections followed by a detailed outpatient regimen. The patient completed a daily dose of vitamin B12 injections for seven consecutive days, followed by weekly injections for the next four weeks. Subsequent laboratory results demonstrated an increase in WBC count to 8.39, Hgb level to 13.2, and PLT count of 249, indicating a continued positive response to the vitamin B12 replacement therapy. In summary, pancytopenia poses a diagnostic challenge that demands careful evaluation of patient data and comprehensive testing. Vitamin B12 deficiency, which encompasses pernicious anemia (PA), is among the reversible factors to consider. This aspect holds significance before opting for more invasive measures like a bone marrow biopsy. Nutritional deficiencies need to be considered first as differentials in pancytopenia, even in the absence of typical signs of vitamin B12 deficiency (like macrocytosis and hypersegmented neutrophils) and in the presence of compelling clinical indications pointing to a hematologic malignancy.

Extracellular vesicles and their associated miRNAs as potential prognostic biomarkers in chronic lymphocytic leukemia.

PURPOSE OF REVIEW: Many prognostic and predictive biomarkers have been proposed for chronic lymphocytic leukaemia (CLL). Here, we aim to discuss the evidence showing a prognostic potential for extracellular vesicles (EV) and their associated microRNAs (miRNAs). RECENT FINDINGS: EV are produced by several cells in the body as a physiological event; however, there is evidence suggesting that an elevated EV concentration is present in the circulation of CLL patients. Moreover, some studies have associated EV concentration with advanced Rai stage and unmutated CLL while others have demonstrated its potential as an independent prognostic factor for TTFT and OS. Finally, some studies have shown that CLL EV shared some dysregulated microRNAs with CLL cells and plasma. On the other hand, it was found that CLL EV has a distinctive microRNA expression profile. Until now, EV-associated miR-155 is the most studied miRNA. Despite methodological diversity and limitations in study design, unanimity in CLL EV concentration behaviour and miRNA content has been found.

Analysis of RNA yield in extracellular vesicles isolated by membrane affinity column and differential ultracentrifugation.

Extracellular vesicles (EV) have attracted much attention as potential biomarkers due to their protein, RNA and other nucleic acid content. The most common method used for EV isolation is differential ultracentrifugation (DU), however given the DU technical difficulties, other more practical methods have surged, such as membrane-affinity column commercial kits. Here, we assessed one commercial kit in terms of EV recovery and EV-derived RNA yield and compared it with a DU protocol. Our data shows that the commercial kit preparation results in a lower count of EV-like structures and a reduced expression of EV markers when compared to DU samples. Thus, apparently suggesting that the commercial kit had a lower EV yield. However, these findings did not reflect on RNA yield, which was greater with the commercial kit, even after an enzymatic treatment with proteinase K and RNAse A. We conclude that the kit has a higher EV-derived RNA yield in comparison to our DU protocol, suggesting that it may be the method of choice for RNA sequencing purposes.