Aplastic anaemia--aetiology and clinical features

Childhood aplastic anaemia in Lucknow, India: Incidence, organochlorines in the blood and review of case reports following exposure to pesticides

OBJECTIVES

A hospital-based case-control study, the first in India, was conducted to determine the incidence of childhood aplastic anaemia in and around Lucknow in the backdrop of organochlorine levels in the blood and review the database for any association between the disease and exposure to pesticides.

DESIGN AND METHODS

A total of 25 cases of childhood aplastic anaemia were identified as per established criteria and enrolled over the study period of 1 year. Their blood organochlorine levels were determined using a gas-liquid chromatograph equipped with an electron capture detector.

RESULTS

The annual incidence of childhood aplastic anaemia in and around Lucknow was found to be 6.8 cases per million which is higher than many countries (e.g., France, Brazil, UK, and United States) but lower than those reported in Sweden, China and an European-Israeli collaborative study. Blood levels of alpha-HCH, gamma-HCH, delta-HCH, total-HCH, and p, p'-DDE were higher in children with aplastic anaemia than in those of controls; only alpha-HCH differed significantly (P < 0.05).

CONCLUSIONS

Although this pilot study, with limited statistical power, did not support any association between exposure to organochlorines and risk of childhood aplastic anaemia, a possible association between the two could not be ruled out in view of several cases identified following exposure to pesticides.

Aplastic anemia in Brazil: incidence and risk factors

This study is the first large-scale epidemiological investigation of acquired aplastic anemia (AAA) in South America. The objective was to estimate the incidence and to identify risk factors for AAA in Brazil. A national case-control study was conducted to investigate the risk factors for the disease. One hundred twenty-five cases and 129 controls were included. Multiple logistic regression was used in the estimation of odds ratios (OR) to control confounding. The size of Brazil made it unfeasible to estimate the incidence of AAA in the whole country, and we limited the calculation to the state of Parana. The annual incidence of AAA in Parana was 2.4 cases/10(6) inhabitants. There was no positive association between chloramphenicol use and AAA (OR 0.4; 95% CI: 0.1-2.9). The OR of AAA associated with household pesticides that include organophosphates in their composition was 2.7 (1.0-8.4). The OR for the usage of unspecified thinner and/or acetone for at least 7 days was 3.0 (1.2-7.3). Cases of AAA in Brazil seem to be associated with some factors traditionally related to this disease, such as certain solvents and the incidence is similar to what has been reported from Europe.

Aplastic Anemia in Systemic Lupus Erythematosus: A Distinct Presentation of Acquired Aplastic Anemia?

Aplastic anemia is a rare but serious complication of systemic lupus erythematosus (SLE) with an often dramatic and unanticipated onset. The peripheral destruction of formed blood elements, which frequently accompanies the syndrome, may obscure or delay the diagnosis of bone marrow suppression, and the number of published cases may be an underestimate of the actual incidence of the disease. Furthermore, the disease course may differ significantly from other forms of acquired aplastic anemia and seems to carry a more favorable prognosis once effectively diagnosed and treated. In addition, aplastic anemia may precede other manifestations of SLE. Therefore, the possibility of bone marrow aplasia should be excluded in all SLE patients with severe pancytopenia, and conversely, the diagnosis of SLE should be explored in cases of aplastic anemia. Two patients with aplastic anemia in SLE, one with aplastic anemia preceding the onset of SLE, are described along with 15 cases reviewed from the English language literature. The presentation, prognosis, treatment, and pathogenesis of aplastic anemia complicating SLE are discussed. Recognition that cytopenias, especially pancytopenia, may occur on the basis of inhibited myelopoesis rather than peripheral destruction as either a harbinger of SLE or as a manifestation of disease flare is important. This knowledge will prompt the astute clinician to obtain screening antinuclear antibodies in the setting of otherwise unexplained bone marrow acellularity or, given the prognosis of SLE associated aplastic anemia, give early consideration to more aggressive immunosuppression.

Fever in the neutropenic host

Fever in the neutropenic patient following myelosuppressive chemotherapy is a medical emergency. Appropriate antimicrobial therapy can dramatically reduce infection-related morbidity and mortality. This article reviews the rationale and methodology of treatment as well as its applicability to other neutropenic states. The utility of adjunct therapy with granulocyte- stimulating compounds is also discussed.

Successful bone marrow transplantation in children with severe aplastic anemia using HLA-partially matched family donors

Bone marrow transplantation (BMT) using HLA-partially matched family donors has produced disappointing results (25-30% of long-term survivors) in patients with severe aplastic anemia. We describe two children affected by severe aplastic anemia, not responsive to immunosuppressive therapy, who underwent allogeneic bone marrow transplantation using a HLA-partially matched family donor. Both cases presented 2 first class HLA-antigens (A and B) disparity between donor and recipient. The pretransplant conditioning regimen consisted of cyclophosphamide, thoracoabdominal irradiation, cytosine-arabinoside, and antilymphocyte globulin. As graft versus host disease (GVHD) prophylaxis, Cyclosporine-A was administered at usual dosages for 6 months. A full marrow engraftment was observed in both cases. Only grade I acute GVHD, promptly responsive to corticosteroid therapy, developed with no chronic GVHD. Five months after transplant, both children progressively developed hypertension, renal function impairment, thrombocytopenia, and severe normochromic anemia, with erythropoietin serum levels lower than expected for the haematocrit. After antihypertension treatment and supportive therapy, the clinical picture progressively improved, while treatment with recombinant human erythropoietin completely corrected the long-lasting anemia. The two children are alive and well 28 months after the transplant, with a Karnofsky score of 100% and a normal peripheral blood count. The authors suggest that, once immunosuppressive therapy has failed, BMT from donors other than HLA-identical sibling is a feasible approach in children affected by severe aplastic anemia, not having an HLA-identical donor.

Severe aplastic anemia associated with seronegative community-acquired hepatitis C virus infection

Aplastic anemia (AA) is a rare complication of viral hepatitis affecting mainly children or young adults. Most reported cases have been associated with community-acquired non-A, non-B hepatitis, but hepatitis A and B have also been implicated in a few patients. We report on a 43-year-old woman with severe AA, in association with acute hepatitis C virus (HCV) infection, diagnosed by detection of HCV RNA by the polymerase chain reaction technique. Her AA was successfully treated with anti-thymocyte globulin and cyclosporin A. The hepatitis C progressed to chronic disease but, despite a follow-up time of 2 years, the patient still has no detectable anti-HCV antibodies, as evaluated with a second-generation anti-HCV assay.

The quantitative study of lumbar vertebral bone marrow using T1 mapping and image analysis techniques: methodology and preliminary results

A method of quantifying lumbar vertebral bone marrow using pixel by pixel T1 mapping of spin echo magnetic resonance images is described. The accuracy and precision of the relaxation time measurements is confirmed by studies with the EEC Concerted Research Project, test object no. 5. The T1 data from all the pixels sampled from lumbar vertebral marrow are displayed as a histogram. By "thresholding" relative to normal control data the spatial distribution of high or low T1 pixels can be demonstrated. The approach is superior to that of the conventional region of interest method for quantifying and analysing relaxation time data, and allows tissue heterogeneity to be studied. Studies in patients with aplastic anaemia and acute leukaemia have been performed.

Aplastic anemia: current concepts and dental management

Aplastic anemia (AA) is a rare blood dyscrasia in which the peripheral blood cells are decreased because of bone marrow failure. The clinical course reflects the severity of pancytopenia and is unpredictable for the individual. Hemorrhage and infection remain the major threats to these patients. Recent advances in transfusion medicine, infection management, bone marrow transplantation, and immunosuppressive therapy have improved survival of patients with AA. Oral manifestations of AA are common and may have serious sequelae. Two cases of acute periodontal infection associated with AA are presented. Dental management guidelines are presented in the context of interdisciplinary care.