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

Transient erythroblastopenia of childhood is an underdiagnosed and self-limiting disease

AIM

Transient erythroblastopenia of childhood (TEC) is an uncommon, benign normocytic anaemia of unknown cause, characterised by reduced or absent mature erythroid precursors in otherwise normocellular bone marrow and a complete spontaneous recovery. We present epidemiological data on paediatric TEC cases in a single centre over 30 years and compare them with published data.

METHODS

In this retrospective study, epidemiological data on children diagnosed with TEC between 1978 and 2008 were collected and compared with published data.

RESULTS

A total of 36 children (median age 19 months, 56% male children) were diagnosed. At presentation, median haemoglobin was 44 g/L with absolute reticulocyte count 0 × 10(9) /L; seventeen (47%) patients were neutropenic and 23 (64%) had platelet counts of more than 400 × 10(9) /L. The majority (78%) presented from 1983 to 1997, and 78% of articles reviewing 10 or more TEC patients were published between 1983 and 1992.

CONCLUSION

Transient erythroblastopenia of childhood is now diagnosed less frequently in our institution than in the last two decades. Although the aetiology remains largely unknown, it is possible that changes in causative environmental factors contribute to making TEC a rare disease. Clinicians need to be aware of TEC in order to prevent unnecessary diagnostic and therapeutic measurements.

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.

Multicolor flow-cytometric, morphologic, and clonogenic analysis of marrow CD10-positive cells in children with leukemia in remission or nonmalignant diseases

PURPOSE

To characterize nonleukemic CD10-positive cells in the marrows of children with leukemia in remission or benign conditions.

PATIENTS AND METHODS

Seventeen children with acute leukemia in complete remission, 12 with solid tumors, and 17 with benign blood diseases were included in this study. Bone marrow cells were analyzed by multicolor flow-cytometry and polymerase chain reaction (PCR) to detect immunoglobulin gene rearrangement. The CD10-positive cells were purely sorted and examined by light microscopy and single cell hemopoietic progenitor assay.

RESULTS

In patients with acute leukemia, CD10-positive cells were present in higher proportion after completion of therapy than during chemotherapy. They were also higher in the patients of preschool age than in the older age group with benign blood diseases and solid tumors. These CD10-positive cells were morphologically compatible with immature lymphocytes but some blast-like cells also occurred in this population. Most CD10-positive cells coexpressed CD19 and HLA-DR, although only 10 to 30% coexpressed CD20 and CD34. Although some CD10-positive cells expressed CD34, they did not make any colonies. PCR analysis did not show monoclonal bands in CD10-positive bone marrow cells in any patients in remission.

CONCLUSION

Marrow CD10-positive cells possess immature B-lymphocyte phenotype and are present in higher proportion in the marrows of children with acute leukemia in continuous complete remission after completion of therapy and children of preschool age than school-age children with benign diseases or solid tumors without marrow involvement. The clonality of these cells was excluded by PCR, which is a distinct point from CD10-positive ALL blasts.

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.

White blood cells in infants with congenital toxoplasmosis: transient appearance of cALL antigen on reactive marrow lymphocytes

Existing serological methods for diagnosing congenital toxoplasmosis are inadequate. We have therefore characterized the features of peripheral blood cell counts and smears in a prospective study of 8 affected infants during their first year of life. Enlarged, vacuolated lymphocytes were observed in all patients. Six patients had periods of neutropenia; in 1 patient the neutropenia was severe and prolonged. A bone marrow aspirate from this patient showed enhanced myelopoiesis, and after stimulation with hydrocortisone, but not with adrenaline, his neutrophil count normalized. Phenotyping of his bone marrow cells revealed that approximately 55% of both the immature and mature B lymphocytes were positive for the cALL antigen. Of the 8 patients, 6 had mild eosinophilia, 4 had mild monocytosis and 3 had increased numbers of plasma cells in the peripheral blood. These findings may reflect the activity of the congenital toxoplasma infection and may thus contribute to the diagnosis, particularly in patients with silent serology.