RESUMEN
Microcephaly is a common feature in inherited bone marrow failure syndromes, prompting investigations into shared pathways between neurogenesis and hematopoiesis. To understand this association, we studied the role of the microcephaly gene Mcph1 in hematological development. Our research revealed that Mcph1-knockout mice exhibited congenital macrocytic anemia due to impaired terminal erythroid differentiation during fetal development. Anemia's cause is a failure to complete cell division, evident from tetraploid erythroid progenitors with DNA content exceeding 4n. Gene expression profiling demonstrated activation of the p53 pathway in Mcph1-deficient erythroid precursors, leading to overexpression of Cdkn1a/p21, a major mediator of p53-dependent cell cycle arrest. Surprisingly, fetal brain analysis revealed hypertrophied binucleated neuroprogenitors overexpressing p21 in Mcph1-knockout mice, indicating a shared pathophysiological mechanism underlying both erythroid and neurological defects. However, inactivating p53 in Mcph1-/- mice failed to reverse anemia and microcephaly, suggesting that p53 activation in Mcph1-deficient cells resulted from their proliferation defect rather than causing it. These findings shed new light on Mcph1's function in fetal hematopoietic development, emphasizing the impact of disrupted cell division on neurogenesis and erythropoiesis - a common limiting pathway.
Asunto(s)
Proteínas de Ciclo Celular , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Eritropoyesis , Ratones Noqueados , Microcefalia , Proteína p53 Supresora de Tumor , Animales , Ratones , Anemia Macrocítica/genética , Anemia Macrocítica/patología , Anemia Macrocítica/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Diferenciación Celular/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Proteínas del Citoesqueleto/genética , Proteínas del Citoesqueleto/metabolismo , Células Precursoras Eritroides/metabolismo , Eritropoyesis/genética , Microcefalia/genética , Microcefalia/patología , Mutación , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
OBJECTIVES: Transcobalamin II (TC) promotes the cellular uptake of cobalamin (Cbl) through receptor-mediated endocytosis of the TC-cbl complex in peripheral tissues. TC deficiency is a rare disorder that causes intracellular Cbl depletion. It presents in early infancy with a failure to thrive, diarrhea, anemia, agammaglobulinemia, and pancytopenia. Data from five TC-deficient patients including clinical, biochemical, and molecular findings, as well as long-term outcomes, were collected. CASE PRESENTATION: Mutation analysis revealed one unreported pathogenic variant in the TCN2 gene. One patient had exocrine pancreatic insufficiency. We conducted a retrospective analysis of C3 and C3/C2 from dried blood samples, as this is implemented for newborn screening (NBS). We detected a marked increase in the C3/C2 ratio in two samples. Treatment was based on parenteral Cbl. Three patients treated before six months of age had an initial favorable outcome, whereas the two treated later or inadequately had neurological impairment. CONCLUSIONS: This is the first report of Argentinean patients with TC deficiency that detected a new variant in TCN2. NBS may be a tool for the early detection of TC deficiency. This data emphasizes that TC deficiency is a severe disorder that requires early detection and long-term, aggressive therapy. Accurate diagnosis is imperative, because early detection and treatment can be life-saving.
Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos , Anemia Macrocítica , Deficiencia de Vitamina B 12 , Recién Nacido , Humanos , Vitamina B 12/uso terapéutico , Transcobalaminas/genética , Estudios Retrospectivos , Deficiencia de Vitamina B 12/diagnóstico , Deficiencia de Vitamina B 12/tratamiento farmacológico , Deficiencia de Vitamina B 12/genética , Errores Innatos del Metabolismo de los Aminoácidos/tratamiento farmacológico , Diagnóstico PrecozRESUMEN
Diamond-Blackfan anemia (DBA) was the first ribosomopathy described in humans. DBA is a congenital hypoplastic anemia, characterized by macrocytic aregenerative anemia, manifesting by differentiation blockage between the BFU-e/CFU-e developmental erythroid progenitor stages. In 50 % of the DBA cases, various malformations are noted. Strikingly, for a hematological disease with a relative erythroid tropism, DBA is due to ribosomal haploinsufficiency in 24 different ribosomal protein (RP) genes. A few other genes have been described in DBA-like disorders, but they do not fit into the classical DBA phenotype (Sankaran et al., 2012; van Dooijeweert et al., 2022; Toki et al., 2018; Kim et al., 2017 [1-4]). Haploinsufficiency in a RP gene leads to defective ribosomal RNA (rRNA) maturation, which is a hallmark of DBA. However, the mechanistic understandings of the erythroid tropism defect in DBA are still to be fully defined. Erythroid defect in DBA has been recently been linked in a non-exclusive manner to a number of mechanisms that include: 1) a defect in translation, in particular for the GATA1 erythroid gene; 2) a deficit of HSP70, the GATA1 chaperone, and 3) free heme toxicity. In addition, p53 activation in response to ribosomal stress is involved in DBA pathophysiology. The DBA phenotype may thus result from the combined contributions of various actors, which may explain the heterogenous phenotypes observed in DBA patients, even within the same family.
Asunto(s)
Anemia de Diamond-Blackfan , Anemia Diseritropoyética Congénita , Anemia Macrocítica , Humanos , Anemia de Diamond-Blackfan/genética , Proteínas Ribosómicas/genética , Proteínas Ribosómicas/metabolismo , Células Precursoras Eritroides/metabolismo , MutaciónRESUMEN
PURPOSE OF REVIEW: Over the last century, the diseases associated with macrocytic anemia have been changing with more patients currently having hematological diseases including malignancies and myelodysplastic syndrome. The intracellular mechanisms underlying the development of anemia with macrocytosis can help in understanding normal erythropoiesis. Adaptations to these diseases involving erythroid progenitor and precursor cells lead to production of fewer but larger red blood cells, and understanding these mechanisms can provide information for possible treatments. RECENT FINDINGS: Both inherited and acquired bone marrow diseases involving primarily impaired or delayed erythroid cell division or secondary adaptions to basic erythroid cellular deficits that results in prolonged cell division frequently present with macrocytic anemia. SUMMARY OF FINDINGS: In marrow failure diseases, large accumulations of iron and heme in early stages of erythroid differentiation make cells in those stages especially susceptible to death, but the erythroid cells that can survive the early stages of terminal differentiation yield fewer but larger erythrocytes that are recognized clinically as macrocytic anemia. Other disorders that limit deoxynucleosides required for DNA synthesis affect a broader range of erythropoietic cells, but they also lead to macrocytic anemia. The source of macrocytosis in other diseases remains uncertain.
Asunto(s)
Anemia Macrocítica , Anemia , Síndromes Mielodisplásicos , Humanos , Eritropoyesis , Anemia/metabolismo , Anemia Macrocítica/metabolismo , Eritrocitos/metabolismo , Síndromes Mielodisplásicos/metabolismoRESUMEN
We investigated the clinical implications of the mean corpuscular volume (MCV) in patients with major trauma. This single-center retrospective review included 2021 trauma patients admitted to the intensive care unit between January 2016 and June 2020. We included 1218 patients aged [Formula: see text] 18 years with an injury severity score [Formula: see text] 16 in the final analysis. The clinical and laboratory variables were compared between macrocytosis (defined as MCV [Formula: see text] 100 fL) and non-macrocytosis groups. Cox regression analysis was performed to calculate the hazard ratios (HRs) of variables for 30-day mortality, with adjustment for other potential confounding factors. The initial mean value of MCV was 102.7 fL in the macrocytosis group (n = 199) and 93.7 fL in the non-macrocytosis group (n = 1019). The macrocytosis group showed a significantly higher proportion of initial hypotension, transfusion within 4 and 24 h, and 30-day mortality than the non-macrocytosis group. Age ([Formula: see text] 65 years), hypotension (systolic blood pressure [Formula: see text] 90 mmHg), transfusion (within 4 h), anemia (Hb < 12 g/day in women, < 13 g/day in men), and macrocytosis were significantly associated with 30-day mortality (adjusted HR = 1.4; 95% confidence interval 1.01-1.94; p = 0.046) in major trauma patients. Thus, initial macrocytosis independently predicted 30-day mortality in patients with major trauma at a Level I trauma center.
Asunto(s)
Anemia Macrocítica , Anemia , Deficiencia de Ácido Fólico , Hipotensión , Masculino , Humanos , Femenino , Anciano , Índices de Eritrocitos , Estudios Retrospectivos , PronósticoAsunto(s)
Anemia Macrocítica , Proteinuria , Humanos , Proteinuria/etiología , Anemia Macrocítica/diagnóstico , Anemia Macrocítica/etiología , Masculino , Niño , FemeninoRESUMEN
An adult-onset autoinflammatory syndrome caused by somatic mutations in the UBA1 gene on the X chromosome was first reported in 2020. This VEXAS syndrome (acronym for vacuoles, E1 enzyme, Xlinked, autoinflammatory, somatic) is characterized by an overlap of rheumatic inflammatory diseases with separate hematologic abnormalities. A substantial number of affected patients suffer from treatment refractory relapsing polychondritis and nearly always show signs of macrocytic anemia. This case report illustrates the diagnostic key points to recognizing patients with VEXAS syndrome.
Asunto(s)
Anemia Macrocítica , Enfermedades Autoinmunes , Síndromes Mielodisplásicos , Policondritis Recurrente , Enfermedades Reumáticas , Enfermedades Cutáneas Genéticas , Adulto , Humanos , MutaciónRESUMEN
Biallelic pathogenic variants in CAD, that encode the multienzymatic protein required for de-novo pyrimidine biosynthesis, cause early infantile epileptic encephalopathy-50. This rare disease, characterized by developmental delay, intractable seizures and anaemia, is amenable to treatment with uridine. We present a patient with macrocytic anaemia, elevated haemoglobin-A2 levels, anisocytosis, poikilocytosis and target cells in the blood smear, and mild developmental delay. A next-generation sequencing panel revealed biallelic variants in CAD. Functional studies did not support complete abrogation of protein function; however, the patient responded to uridine supplement. We conclude that biallelic hypomorphic CAD variants may cause a primarily haematological phenotype.
Asunto(s)
Anemia Macrocítica , Anemia , Espasmos Infantiles , Humanos , Espasmos Infantiles/genética , Uridina , HemoglobinasRESUMEN
BACKGROUND: The hypothyroid phenotype associated with resistance to thyroid hormone alpha (RTH-α) is associated with a diverse clinical picture. On the other hand, thyroid-stimulating hormone (TSH) levels are normal. Free triiodothyronine (fT3) and free thyroxine (fT4) levels can also be normal; however, normo- or macrocytic anaemia is usually present in reported cases. Diagnosis is challenging and there is limited data regarding screening methods. OBJECTIVE: The study aimed to assess the efficiency of a screening strategy for RTH-α. SUBJECTS AND METHODS: Out of a total of 6540 children evaluated at the outpatient clinics of paediatric neurology over 2 years and who underwent complete blood count and thyroid function tests, 432 were found to have anaemia. Within this group, we identified 42 children without an underlying specific neurological aetiology who exhibited normo- or macrocytic anaemia, normal TSH levels, fT3 levels in the upper half of the normal range or high, and fT4 levels in the lower half of the normal range or low. We excluded one patient who had already been diagnosed with RTH-α and nine patients could not be reached. Subsequently, clinical evaluation, biochemical assessment, and THRA sequencing analysis were conducted on 32 children. The findings were compared with those of the known RTH-α patients in our unit. RESULTS: The median age of the patients was 5.7 (5.1-7.4) years, and 22 of them were males (69%). The main reasons for assessment in paediatric neurology clinics were autism spectrum disorder (n = 12, 38%), epilepsy (n = 11, 34%), and delay in developmental stages (n = 8, 25%). Constipation was present in five of the cases (16%), while the closure of the anterior fontanelle and tooth eruption were delayed in two cases (6%) and one case (3%), respectively. The median length/height and weight standard deviation (SD) scores were 0.3 [(-0.8)-(1.1)] and -0.1 [(-0.8)-(0.3)], respectively. The median fT3, fT4, and TSH levels were 4.6 (4.2-5.0) pg/mL, 0.9 (0.8-1.0) ng/dL, and 2.2 (1.8-3.1) uIU/mL, respectively. Thirteen of the patients (41%) had high fT3 levels, while none of them had low fT4 levels. The normo- or macrocytic anaemia rate was 47% (normocytic/macrocytic, n = 8/7) at the time of reassessment. Serum creatine kinase (CK) was elevated in five patients (16%; one had anaemia). None of the subjects had a pathological variant in THRA. Known RTH-α patients had significantly lower median height SD score, higher rates of delayed tooth eruption and closure of the anterior fontanelle, lower haemoglobin levels, and higher mean corpuscular volume (MCV) and CK levels as compared to those found without RTH-α. CONCLUSIONS: This approach found one known patient with RTH-α but did not reveal any new cases. Notably, normo- or macrocytic anaemia did not persist in nearly half of the screened patients. A screening strategy that takes clinical findings and prominent laboratory features suggestive of RTH-α into account could lower unnecessary genetic analysis of THRA in patients presenting with neurological problems.
Asunto(s)
Anemia Macrocítica , Trastorno del Espectro Autista , Masculino , Niño , Humanos , Preescolar , Femenino , Tiroxina , Triyodotironina , Hormonas Tiroideas , Pruebas de Función de la Tiroides , TirotropinaRESUMEN
RATIONALE: Anorexia nervosa is characterized by an extreme fear of weight gain. Clinicians often prescribe meal replacement shakes if patients are unable or unwilling to consume typical foods. However, these shakes sometimes lack essential micronutrients, such as selenium, which may lead to health risks. Moreover, selenium deficiency induces macrocytic anemia. Herein, we present a case of a patient with anorexia nervosa with macrocytic anemia due to selenium deficiency, which was alleviated by selenium supplementation. PATIENT CONCERNS: An 18-year-old female was admitted to our hospital. The patient was diagnosed with anorexia nervosa. Ultimately, she was unable to walk independently because of fatigue and electrolyte disturbances. CLINICAL FINDINGS: On admission, the height, weight, and body mass index of the patient were 158.5 cm, 27.1 kg, and 10.8, respectively. Our treatment for anorexia nervosa showed relative effectiveness, and the patient's body weight recovered to 29.2 kg by day 60. However, the mean corpuscular volume increased from day 20, suggesting macrocytic anemia. DIAGNOSES, INTERVENTIONS, AND OUTCOMES: Despite our vitamin B12 and folic acid supplementation interventions, the mean corpuscular volume continued to rise. On day 60, the patient was diagnosed with selenium deficiency, and selenium administration of 100 µg/day was initiated. OUTCOMES: The macrocytic anemia in the patient was alleviated, and treatment for anorexia nervosa was continued in our hospital. LESSONS: To the best of our knowledge, this is the first case of macrocytic anemia induced by selenium deficiency with anorexia nervosa comorbidity, underscoring the importance of selenium supplementation in patients with anorexia nervosa, especially in those with macrocytic anemia.
Asunto(s)
Anemia Macrocítica , Anorexia Nerviosa , Desnutrición , Selenio , Femenino , Humanos , Adolescente , Anorexia Nerviosa/complicaciones , Anorexia Nerviosa/diagnóstico , Selenio/uso terapéutico , Índice de Masa CorporalRESUMEN
Macrocytic anemia is divided into megaloblastic and nonmegaloblastic causes, with the former being more common. Megaloblastic anemia results from impaired DNA synthesis, leading to release of megaloblasts, which are large nucleated red blood cell precursors with chromatin that is not condensed. Vitamin B12 deficiency is the most common cause for megaloblastic anemia, although folate deficiency also can contribute. Nonmegaloblastic anemia entails normal DNA synthesis and typically is caused by chronic liver dysfunction, hypothyroidism, alcohol use disorder, or myelodysplastic disorders. Macrocytosis also can result from release of reticulocytes in the normal physiologic response to acute anemia. Management of macrocytic anemia is specific to the etiology identified through testing and patient evaluation.
Asunto(s)
Alcoholismo , Anemia Macrocítica , Anemia Megaloblástica , Anemia , Humanos , Anemia Macrocítica/diagnóstico , Anemia Macrocítica/terapia , Anemia/etiología , Anemia/terapia , Anemia Megaloblástica/diagnóstico , Anemia Megaloblástica/terapia , ADNRESUMEN
To explore the characteristics of hemogram in patients with aplastic anemia (AA), especially mean corpuscular volume (MCV) and red cell distribution width (RDW). We examined the blood routine of 180 new-onset AA patients and used 166 patients with myelodysplastic syndrome (MDS) as controls. Among the 180 AA patients, 105 (58.3%) were diagnosed with severe AA (SAA), while 75 (41.7%) were diagnosed with non-severe AA (NSAA). Compared to MDS, patients with SAA generally had unfavorable hemogram, including significantly lower white blood cell (WBC), absolute neutrophil count (ANC), hemoglobin (Hb), platelet (PLT) and reticulocyte counts (RET). However, WBC, ANC and lymphocyte counts were higher in the NSAA group than in the MDS group; Hb and Ret were comparable between the two groups. 8.5% of SAA patients and 58.1% of NSAA patients presented with macrocytic anemia, whereas 25.7% of SAA and 64.0% of NSAA had a high RDW. In the MDS group, 54.7% of patients presented with macrocytic anemia, and 84.7% had increased RDW. WBC, ANC, PLT, and Ret in a high-RDW group (25.7% of SAA) were significantly higher than in a normal-RDW group (74.3% of SAA). Overall, most SAA patients exhibited normocytic-normochromic anemia, and their hemograms decreased more significantly; more than half of NSAA patients showed macrocytic-heterogeneous anemia, and their hemograms were similar to those of MDS. Patients with elevated RDW may have better residual bone marrow hematopoietic function than those with normal RDW but with more severe anemia.
Asunto(s)
Anemia Aplásica , Anemia Macrocítica , Humanos , Anemia Aplásica/diagnóstico , Índices de Eritrocitos , Médula Ósea , HemoglobinasRESUMEN
BACKGROUND: VEXAS-syndrome is an X-linked acquired multisystemic autoinflammatory disease caused by a somatic mutation in UBA1. CASE DESCRIPTION: In this manuscript we describe a 79-year-old male suffering from skin lesions, macrocytic anemia and lab results showing inflammation in which, based on finding a mutation in UBA1, VEXAS was diagnosed. He was treated with a combination of high dose corticosteroids and anti-IL-6 with good response. CONCLUSION: In middle aged males presenting with multisystemic inflammation without evidence of infection a diagnosis of VEXAS should be considered, especially if there is evidence of a macrocytic anemia. Early testing for UBA1 mutations helps in making the diagnosis. Despite treatment with intensive immunosuppression mortality remains high.
Asunto(s)
Anemia Macrocítica , Anemia , Masculino , Persona de Mediana Edad , Humanos , Anciano , Anemia/diagnóstico , Anemia/etiología , Inflamación , MutaciónRESUMEN
INTRODUCTION: Anemia frequently occurs during course of clinical thyroid diseases. Without proper diagnosis & effective treatment of underlying thyroid disease, it is often difficult to achieve complete correction of anemia. AIM: The present study was conducted to assess prevalence & types of anaemia in patients with thyroid disorders. MATERIALS: A cross sectional study was conducted on 160 patients including both hypothyroid & hyperthyroid patients at OPD/IPD in SRN Hospital affiliated to MLN Medical college Prayagraj between July 2021 & August 2022. Blood samples were taken to estimate CBC, GBP with Retic count, S. ferritin, S. folate, S. Vitamin B12, Thyroid profile. Data was entered in MS Excel Spreadsheet & appropriate statistical package applied. RESULT: Out of 144 hypothyroid patients, 102 (70.83%) were found to be anaemic & out of 16 hyperthyroid patients, 6 (37.5%) were found to be anaemic. In 102 anaemic hypothyroid patients, 56 (54.9%)had normocytic normochromic, 25 (24.5%) had microcytic and 21 (20.5%) had macrocytic anaemia. In 6 anaemic hyperthyroid patients, 3 (50%) had normocytic normochromic, 2(33.33%) had microcytic and 1 (16.67%) had macrocytic anaemia. CONCLUSION: High prevalence of anaemia was found in patients with thyroid disorders. Anaemia is an uncommon finding in hyperthyroidism but when present may be similar to that present in hypothyroidism. The most common type of anaemia in both hyperthyroidism & hypothyroidism was found to be normocytic normochromic, followed by microcytic & least common being macrocytic. References Suhail N, Abu Alsel BT, Batool S. Prevalence and association of thyroid dysfunction with anemia/body iron status among northern border Saudi population. Int J Med Res Health Sci 2020;9(3):1-7. Peraka SA, Karre S, Ravuri S, et al., To evaluate prevalence of anemia in hypothyroid patients. J Diagn Pathol Oncol 2019;4(2):110-113.
Asunto(s)
Anemia Macrocítica , Anemia , Hipertiroidismo , Hipotiroidismo , Enfermedades de la Tiroides , Humanos , Ácido Fólico , Vitamina B 12 , Estudios Transversales , Hormonas Tiroideas , Enfermedades de la Tiroides/complicaciones , Enfermedades de la Tiroides/epidemiología , Hipotiroidismo/epidemiología , Hipotiroidismo/complicaciones , Hipertiroidismo/complicaciones , Hipertiroidismo/epidemiología , Anemia Macrocítica/complicaciones , FerritinasRESUMEN
BACKGROUND: Pre-operative anaemia is common and associated with adverse outcomes. We hypothesised that pre-operative anaemia would be evident more than 1 month pre-operatively, and that peri-operative changes in haemoglobin and post-operative outcomes differed between red cell size-based subsets of anaemia. METHODS: A retrospective single-centre cohort study, including all patients 18 years and older undergoing their first surgery at Landspitali between January 2006 and December 2018 with available measurement of haemoglobin (Hb) within 30 days preceding surgery. Clinical data were compared between patients with subgroups of anaemia classified by mean corpuscular volume (MCV) into microcytic (MCV < 80 fl), normocytic (MCV 80-100 fl), and macrocytic (MCV > 100 fl) anaemia. The development of haemoglobin measurements from a nationwide database was plotted from 1 year pre-operatively to 2 years post-operatively. RESULTS: Of 40,979 patients, 10,505 (25.6%) had pre-operative anaemia, of which 1089 (10.4%) had microcytic anaemia, 9243 (88.0%) had normocytic anaemia, and 173 (1.6%) had macrocytic anaemia. Patients within all subgroups of pre-operative anaemia had a higher degree of comorbidity and frailty burden and a low haemoglobin evident for more than 100 days pre-operatively and similar changes post-operatively. Post-operative prolonged recovery of haemoglobin was slower for macrocytic anaemia than other types of anaemia. All groups of patients with anaemia had a higher incidence of 30-day mortality, acute kidney injury, and rate of readmission compared with patients without anaemia. CONCLUSIONS: Pre-operative anaemia is evident long prior to the procedure and its association with worse outcomes is similar regardless of red cell size.