Differentiation of transient erythroblastopenia of childhood from congenital hypoplastic anemia

Diagnosing Transient Erythroblastopenia of Childhood: A Review for Pediatricians

Transient erythroblastopenia of childhood is a rare, benign, self-limited condition seen in infants and young children. Laboratory studies will show moderate or severe normochromic normocytic anemia accompanied by absent or low reticulocytes, neutropenia, and mild thrombocytosis or thrombocytopenia. The etiology is unclear, but it has been associated with clinical or laboratory evidence of a recent viral syndrome. Initial diagnostic studies should be aimed at identifying potential causes of anemia, but a confirmed diagnosis is usually obtained once the hemoglobin level has normalized spontaneously. Differentiation from Diamond-Blackfan anemia is critical, especially in infants. Once the diagnosis is established, treatment is supportive, but red blood cell transfusion is indicated in severe cases. High clinical suspicion is imperative to avoid needless diagnostic and therapeutic measures. [Pediatr Ann. 2024;53(1):e34-e36.].

Diamond Blackfan anemia: a model for the translational approach to understanding human disease

Diamond Blackfan anemia (DBA) is an inherited bone marrow failure syndrome. As with the other rare inherited bone marrow failure syndromes, the study of these disorders provides important insights into basic biology and, in the case of DBA, ribosome biology; the disruption of which characterizes the disorder. Thus DBA serves as a paradigm for translational medicine in which the efforts of clinicians to manage DBA have informed laboratory scientists who, in turn, have stimulated clinical researchers to utilize scientific discovery to provide improved care. In this review we describe the clinical syndrome Diamond Blackfan anemia and, in particular, we demonstrate how the study of DBA has allowed scientific inquiry to create opportunities for progress in its understanding and treatment.

Normalization of red cell enolase level following allogeneic bone marrow transplantation in a child with Diamond-Blackfan anemia

We describe a girl with Diamond-Blackfan anemia with accompanying red cell enolase deficiency. At the age of 9 yr old, the patient received allogeneic bone marrow transplantation from her HLA-identical sister who had normal red cell enolase activity. While the post transplant DNA analysis with short tandem repeat has continuously demonstrated a stable mixed chimerism on follow-up, the patient remains transfusion independent and continues to show a steady increase in red cell enolase activity for over two and a half years following bone marrow transplantation.

A practical approach to the evaluation of the anemic child

Anemia is a sign of disease and not a final diagnosis. The clinician's goal is to define the underlying cause. The anemia may be due to decreased production or Increased destruction or loss of red blood cells. Integration of the results of the initial CBC. particularly the RBC indices, the peripheral blood smear, the history and the physical examination can help organize the focus of further evaluations and, ultimately, minimize the number of tests needed to make a firm diagnosis.

Diamond-Blackfan anaemia

Diamond-Blackfan anaemia (DBA) has had an intellectual allure for decades for clinical and experimental haematologists. The syndrome has a haematological phenotype of early-onset red-cell aplasia but is coupled with a baffling array of pleiotropy. There is discordance with modes of inheritance, physical anomalies, erythropoietic response to corticosteroid therapy, spontaneous 'remissions', and evolution to malignant myeloid transformation and to cancer. The recent discovery of two genes associated with DBA is the entry point for explaining the diversity of the phenotype and for understanding the molecular basis of the syndrome.

Interpretation of the complete blood count

The authors' impression is that the CBC provides much more information than is routinely used. When anemia is present, the CBC contains considerable information regarding its cause, which can assist in formulating a differential diagnosis and directing further evaluation. White blood cell and platelet count levels may similarly direct practitioners to consider or dismiss underlying conditions. This article assists the pediatrician in optimizing use of this familiar diagnostic tool.

Transient erythroblastopenia of childhood in Sweden: incidence and findings at the time of diagnosis

All cases of transient erythroblastopenia in children less than 10 years of age, diagnosed in Sweden during the years 1987-89, were identified. Almost all (51/53) were less than 3 years of age. In this group, the incidence was 4.3/100 000, which is the same as that of acute lymphatic leukaemia. No geographical, but a possible temporal, cluster was seen in 1989. The anaemia was severe in some cases; haemoglobin concentration was less than 40 g/l in 8 of 53 children. Thrombocytosis and neutropenia were common and were attributed to high endogenous erythropoietin activity. Thirty-seven of 53 children were given a blood transfusion. All children recovered and no complications or relapses were seen. Transient erythroblastopenia of childhood is a benign disease, and it is important to make a correct diagnosis to prevent unnecessary anxiety for leukaemia or aplastic anaemia.

A regional experience of red cell aplasia

The incidence and current management of red cell aplasia in children was determined from a retrospective survey of haematologists and paediatricians in the northern health region of England over a 7-year period. Thirty-three children were diagnosed: 4 had Diamond Blackfan anaemia, 22 transient erythroblastopenia of childhood, and 7 parvovirus B19 aplasia, with annual incidences of 1, 5 and 2 per 1,000,000 children respectively. Many were over-investigated. Three with Diamond Blackfan anaemia were steroid responsive. One with transient erythroblastopenia was retrospectively diagnosed because anaemia did not recur after steroids were stopped. Transient erythroblastopenia is the most common single cause of red cell aplasia in immunocompetent children. Time, observation and bone marrow examination before steroid therapy are the ways to distinguish transient erythroblastopenia from Diamond Blackfan anaemia or leukaemia. Interpretation of red cell indices using age-related percentiles may reduce the number of inappropriate investigations of the anaemia, but is often unhelpful in distinguishing the various causes of red cell aplasia.

Anaemia and macrocytosis--unrecognized features in cartilage-hair hypoplasia

Cartilage-hair hypoplasia is an autosomal recessive osteo-chondrodysplasia which results in short stature, sparse hair and impaired cell-mediated immunity. In a study of 88 Finnish patients we found episodes of anaemia and/or macrocytosis during childhood in 86% of the patients. The reticulocyte index was always low in relation to anaemia. Bone marrow examination revealed decreased erythropoiesis in six of eight anaemic patients studied. Anaemia was most prevalent and severe during infancy. Spontaneous recovery occurred before adulthood in all patients except in three infants with fatal hypoplastic anaemia. Sixty-two percent of the patients had had lymphopenia and 24% neutropenia. Presence of anaemia significantly correlated to severity of immunodeficiency and growth failure and to presence of neutropenia. Disordered erythrogenesis is an integral feature of cartilage-hair hypoplasia and may, together with growth failure and immunodeficiency, reflect a generalized defect in cellular proliferation.

Transient erythroblastopenia in the first year of life

The distinction between transient erythroblastopenia of childhood (TEC) and congenital red cell aplasia (Blackfan-Diamond anemia) is usually possible at presentation using clinical and laboratory data. When hypoplastic anemia occurs in the first year of life, however, the distinction is more difficult. We describe 7 infants with hypoplastic anemia who illustrate this diagnostic dilemma.

Increase of CALLA-positive stimulated lymphoid cells in transient erythroblastopenia of childhood

In 1986 and 1987 11 children with TEC (transient erythroblastopenia of childhood) were referred to our hospital. Bone marrow aspirations were performed to exclude haematological malignancy. There was a marked reduction of erythropoiesis in 9 cases (1%-8%), two children had already recovered (33% and 44% erythropoiesis). Eight patients exhibited high percentages of stimulated lymphoid cells. The subsequent immunotyping revealed the expression of CALLA (common acute lymphoblastic leukaemia antigen) on these cells but there was no other sign for malignancy. The patients recovered without any specific treatment except transfusions of packed red cells. Eight patients were followed up 11-18 months after initial presentation and were all found to be in good health. A prominent increase of CALLA-positive stimulated lymphoid cells has also been found in other haematological diseases such as neutropenia and immune thrombocytopenia. The expression of CALLA in bone marrow lymphocytes is a general reactive change to various alterations.

Transient erythroblastopenia of childhood: implications for nurse practitioners

Pediatric nurse practitioners in all areas of practice encounter anemic children. This article describes transient erythroblastopenia of childhood (TEC), a rare type of anemia that baffles health care providers and causes anxiety in parents. Understanding the cause, course, and treatment of TEC allows the nurse practitioner to educate and reassure affected children and their parents.

Temporal clustering of transient erythroblastopenia (cytopenia) of childhood

A temporal cluster of four cases of transient childhood erythroblastopenia is described. In all cases there was an associated transient neutropenia and in one case a transient mild thrombocytopenia. In all cases reticulo-endothelial iron overload was a prominent feature but there was no evidence of a pre-existing chronic haemolytic state. All children made a full recovery with only supportive treatment, although in three cases blood transfusion was necessary.

Congenital hypoplastic anaemia in Arab children (Diamond-Blackfan syndrome)

Three Arab children with congenital hypoplastic anaemia are reported. The three children presented with pallor in the first 3 months of life. All were given corticosteroids at different times. The first child is on high doses of prednisone and also needs blood transfusion every 6 weeks. The second child is on 5 mg prednisone every other day and is in remission. The third has been in complete remission for the last 5 years and is on no treatment. None of these children has associated congenital or chromosomal abnormalities.

Comparative activity of erythrocyte adenosine deaminase and orotidine decarboxylase in Diamond-Blackfan anemia

It previously has been reported that red blood cells (RBC) of patients with Diamond-Blackfan syndrome (DBS) have increased activity of orotidine decarboxylase (ODC) and adenosine deaminase (ADA). The studies reported here compared the activity of these two enzymes in DBS erythrocytes, cord blood, and reticulocytes. The activity of ODC, although increased in some DBS erythrocytes, was not significantly different from that seen in cord RBC or reticulocytes. In contrast, RBC-ADA activity was increased in 23 of 26 DBS patients; and this enzyme elevation was distinct from that seen in cord blood and reticulocytes. Moreover, ADA activity was normal in 26 of 27 patients with transient erythroblastopenia of childhood (TEC). Taken together, these data indicate RBC-ADA activity is more sensitive than ODC as a marker of DBS. In addition, RBC-ADA activity continues to be useful for distinguishing DBS and TEC in most patients with RBC hypoplasia.

Transient erythroblastopenia of childhood. A review of 22 cases

In the period 1975-1983 22 patients, aged 4-36 months were seen with severe transient normochromic, normocytic anaemia caused by a transient erythroblastopenia. In 20 patients bone marrow aspirations were obtained; they showed erythroblastopenia. In ten cases we observed young lymphoid cells, suggesting a diagnosis of acute lymphoblastic leukaemia. One patient suspected of a leukaemia, was studied in more detail. All patients showed reticulocytopenia. MCV and HbF were within normal range. During recovery reticulocytosis and higher levels of HbF were found. Except for blood transfusion in most patients, therapy (e.g. corticosteroids) was not necessary. Spontaneous recovery is a feature of this kind of erythroblastopenia, contrasting with congenital hypoplastic anaemia.

Elevated erythrocyte adenosine deaminase activity in congenital hypoplastic anemia

Abnormalities of adenosine deaminase, a critical enzyme of the purine salvage pathway, have been reported in association with immune dysfunction, acute leukemia, and hereditary hemolytic anemia. We report data showing that erythrocyte adenosine deaminase activity is also abnormal in congenital hypoplastic anemia (the Diamond-Blackfan syndrome). Adenosine deaminase activity in erythrocytes from 12 patients (mean +/- S.D., 2.20 +/- 0.77 IU per gram of hemoglobin) was substantially greater than that observed in 50 controls (0.62 +/- 0.13 IU per gram). Enzyme activity in affected patients was also greater than that seen in cord blood or in erythrocytes from patients with hemolytic anemia, acquired aplastic anemia, Fanconi's hypoplastic anemia, acquired pure red-cell aplasia, or transient erythroblastopenia of childhood. These observations indicate that erythrocyte adenosine deaminase activity may be a unique marker for identifying congenital hypoplastic anemia.

Transient erythroblastopenia of childhood: varied pathogenesis

The mechanism of anemia in four patients with transient red cell aplasia of childhood ("erythroblastopenia") was studied at the time of diagnosis by assessing the colony growth of marrow erythroid progenitors in methylcellulose tissue cultures. Marrow from Patient 1 yielded high normal numbers of BFU-E colonies that were completely abolished on addition of autologous serum or IgG. Patient 2 had normal BFU-E growth that markedly declined when autologous serum or IgM was added to the cultures, but growth remained unchanged with added autologous IgG or peripheral blood mononuclear cells (PBMC). Marrow from Patient 3 yielded low CFU-E and BFU-E numbers with standard plating techniques, but colonies strikingly increased when marrow fractions from an albumin density gradient were cultured. PBMC from Patient 3 suppressed control marrow CFU-E and BFU-E, but serum had no effect. Patient 4 had normal CFU-E and BFU-E that increased with autologous serum and remained unchanged with autologous PBMC. We conclude that the red cell aplasia in Patients 1, 2, and 3 was due to suppressed erythropoiesis via IgG, IgM, and cell-mediated inhibition, respectively. In contrast, in Patient 4 no immune mechanism was demonstrated. Whereas transient red cell aplasia has a uniform clinical presentation, there are at least four pathogenetic mechanisms that can be detected in vitro.

The aplastic presentation of childhood leukaemia: a feature of common-ALL

Transient pancytopenia preceded the onset of acute leukaemia in eight of 360 (2%) of children with acute lymphoblastic leukaemia (ALL) but did not occur in 70 cases of acute non-lymphoblastic leukaemia. The patients developed overt leukaemia within 5-38 weeks of first presentation with features of marrow failure. Immunological classification of blast cells was performed in six of the eight patients and all had phenotype of common-ALL (c-ALL). We conclude that the sydnrome of pre-leukaemia aplasia in childhood is a feature of c-ALL.

alpha-Aminoadipic aciduria and persistence of fetal haemoglobin in an oligophrenic child

The case of a mentally retarded girl with a number of dysmorphic features, Raynaud's phenomenon, hypotonia and petit mal seizures is presented. Laboratory investigations showed alpha-aminoadipic aciduria and a high level of fetal haemoglobin. Oral L-lysine loading resulted in a marked increase of alpha-aminoadipic acid in blood and urine. After 3 months of pyridoxine medication the increase of alpha-aminoadipic acid in blood and urine during the oral L-lysine loading test was less than in the test before treatment. A normal degradation rate of DL-alpha-amino [1-14C] adipic acid in fibroblasts of the patient, as measured by 14CO2 production, did not indicate a primary enzyme defect in the alpha-aminoadipic acid transamination or decarboxylation steps. The persistent HbF could be the result of stress on the erythropoiesis by a secondary induced defect in an early stage of haemoglobin synthesis in which alpha-amino-beta-ketoadipic acid, a structural analogue of alpha-amino-adipic acid, is an intermediate.

Aplastic and hypoplastic anemia

Aplastic anemia is an acquired or constitutional trilineage bone marrow failure with peripheral pancytopenia, evidence of cellular hypoplasia of marrow, and replacement of normal cellular elements by fat. In some cases the marrow may be hypoplastic and the peripheral cytopenia relatively mild. The condition may persist for years and result in acute leukemia. In other cases, hypoplasia may involve only a single cell line. Basic research is directed toward understanding the multitude of cells, with a view toward selective manipulation of the cells themselves, interacting hormones, or cellular regulators. Early bone marrow transplantation presently offers the most hope when compatible donors are available.

Elevation of pyrimidine enzyme activities in the RBC of patients with congenital hypoplastic anaemia and their parents

The activities of orotate phosphoribosyl transferase (OPRT) and orotidine monophosphate decarboxylase (ODC) were significantly elevated (P less than 0.001) in erythrocytes (RBC) from five patients with prednisone-responsive congenital hypoplastic anaemia (CHA). (OPRT: patients - 10.1--64.2 nmol/h/10(9) RBC; controls - 2.8 +/- 0.3 (mean +/- SEM, n = 37); ODC: patients = 30--124 nmol/h/10(9) RBC; controls = 10.2 +/- 0.7 (mean SEM, n = 37).) Two patients had a less pronounced, but significant, increase of aspartate transcarbamylase activity and three patients had marginal increases of dihydroorotase activity. Dihydroorotate dehydrogenase activity was not detected in any CHA patient or control. In one patient prior to prednisone therapy, the OPRT and ODT activities were elevated 10-fold and remained elevated 3-fold after 16 months of therapy. An elevated enzyme pattern similar to that of RBC from CHA patients was observed in three parents of three CHA patients, but not in three parents of two other CHA patients. The activities of all five pyrimidine enzymes were normal for one patient with transient erythroblastopenia of childhood. In contrast, the activities of all the pyrimidine biosynthetic enzymes were elevated in blood from patients with a young RBC population: sickle cell anaemia, sickle-beta-thalassaemia, hereditary spherocytosis, and DiGuglielmo syndrome and from the newborn. It is postulated that factors which affect the activities of pyrimidine enzymes in CHA may also result in diminished erythropoiesis.

Transient erythroblastopenia in childhood. A study of 15 cases

A survey is presented of 15 patients from the Aurora Hospital and 35 patients reported in the literature with transient erythroblastopenia of childhood (TEC). The children were hospitalized because of pallor and tiredness, some of them having signs of mild infection. They displayed normochromic anaemia, reticulocytopenia and erythroblastopenia during the severe stage of the disease. In addition, they had moderately high values for serum iron and iron-binding saturation. No other haematological, chemical or cytogenetic abnormalities could be demonstrated. 80% of the children were between 6 and 48 months old and the sexes were equally affected. In the 15 patients from the Aurora Hospital a barely significant (p=0.02-0.05) association with blood group A was recorded. Remission, indicated by a rise in the reticulocyte count, begins within a week after the diagnosis is made, even without treatment. The aetiology of the disease is unknown. Analysis of the red blood cell population at the time of diagnosis indicates that damage to the red cell precursors has occurred 2-3 months before the child is brought for examination.