Nonradioactive in situ hybridisation of the translocation t(1;7) in myeloid malignancies

Bone marrow cells of four patients with t(1;7) and myelodysplasia or acute myeloid leukemia were analyzed using nonradioactive in situ hydridisation. As probes, centromeric alphoid DNA sequences of chromosomes 1 and 7, a satellite DNA probe for 1q12, and chromosome-specific libraries of chromosomes 1 and 7 were used. The breakpoints of the t(1;7)(p11;p11) as determined by banding analysis could be studied more accurately, and the recently proposed designation t(1;7)(cen;cen) was confirmed in all four cases. Colocalization of alphoid DNA sequences of chromosomes 1 and 7 by double target in situ hybridisation was demonstrated in metaphase cells and also in interphase nuclei. The in situ hybridisation method described is applicable for the screening of peripheral blood cells or archival material.

Hyaline-vascular type Castleman's disease with concomitant malignant B-cell lymphoma

This case report describes a patient with localized hyaline-vascular (H-V) type Castleman's disease with concomitant malignant B-cell lymphoma. Malignant lymphoma has been described in association with multicentric type Castleman's disease, but not in association with the localized H-V type. Evidence for a relation between the two lesions in this patient by means of histologic, flow-cytometric, cytogenetic and gene rearrangement studies was not found.

der(1)t(1;9): a specific chromosome abnormality in polycythemia vera? Cytogenetic and in situ hybridization studies

Two patients with polycythemia vera and an extra der(1)t(1;9) chromosome are reported. In one patient this was found as the sole abnormality. The other patient originally presented with trisomy 9 but later developed an extra der(1) during the further course of the disease with disapperance of the extra chromosome 9. In situ hybridization studies on this latter patient proved that the centromere of chromosome 1 was involved in the formation of the derivative chromosome.

[Are hematologic reference values applicable to the healthy elderly?]

In the healthy elderly (65-90 years; 80 men, 75 women) the variability of haematological findings was examined and compared with the reference range. In the men, the ranges for haemoglobin valves (7.4-10.5 mmol/l) and erythrocyte counts (3.8-5.5 x 10(12)/l) proved to be lower than the reference intervals (8.5-10.9 mmol/l and 4.4-6.0 x 10(12)/l respectively). For the women no discrepancies were found. The question arises whether the reference limits for haemoglobin and erythrocytes should be lowered for elderly men.

Utility of the FAB classification for myelodysplastic syndromes: investigation of prognostic factors in 237 cases

The utility and prognostic significance of the FAB classification was studied in 237 patients with a myelodysplastic syndrome. No significant differences in actuarial survival and probability of transformation to acute leukaemia were found in patients with RA, AISA or CMML. The median survival time for the RA group was 50 months, for the AISA and CMML subclasses more than 60 months. The probability of transformation for the RA, AISA and CMML subgroups showed a linear trend with a probability of 25% for the RA, 16% for the AISA and of 18% for the CMML groups after a 5 year observation period. A uniformly poor prognosis was found for the RAEB and RAEB/t subgroups with median survival times of respectively 9 and 6 months. Chromosomal abnormalities were found in 68 out of 155 patients (44%). Patients with only normal metaphases or with abnormal metaphases together with karyotypic normal cells had a longer median survival time and a lower probability for transformation as compared to those with only abnormal metaphases. The most important factor in prognosis is the number of blast cells in blood and bone marrow. Age and sex, and certain quantitative and qualitative abnormalities in the peripheral blood appear of limited prognostic value for patients with RA, AISA and CMML. The longer life expectancy of 35 patients with CMML as compared to other series seems to be related to the percentage of blast cells at the time of diagnosis.

Significance of in vitro cultures in myelodysplastic syndromes

Bone marrow samples from 20 controls, 41 patients suffering from various types of myelodysplasia and 19 suffering from ANLL were investigated by in vitro cultures. The cultures were stimulated by various concentrations of leucocyte conditioned medium (LCM) and PHA-stimulated conditioned medium (PCM) and were examined after 7 and 14 d. We found that, in clinically stable MDS, growth patterns and dose-response to CM's were mostly within the normal range. With progressive blastic transformation, these features became abnormal with an increase in cluster growth. Clusters responding to a high dose of LCM, persisting after 14 d and enhanced by PCM may represent 'early' clonogenic cells. These clusters were found in progressive MDS with increased numbers of blast cells. Clusters formed by 'late' clonogenic cells were found in normal bone marrow and stable MDS. In ANLL the disturbance of proliferation and maturation seems to be much more pronounced than in progressive MDS with blastic transformation. We conclude that the interpretation of in vitro bone marrow culture data in terms of a disorderly arrangement of clonogenic cells in MDS and ANLL is facilitated by comparing different conditioned medium stimulations and by scoring after different time intervals.

Acute myelomonocytic leukaemia and acquired haemophilia A with severe cutaneous haemorrhage

A case of severe cutaneous haemorrhage due to thrombocytopenia in combination with an acquired haemophilia A is reported. The thrombocytopenia was due to acute myelomonocytic leukaemia (FAB M4). A factor VIII:C specific anticoagulant was also found. Chemotherapy led to complete remission with normal blood counts and coagulation-test results.

Trisomy of chromosome 22 in acute myelomonocytic leukemia

A patient with acute myelomonocytic leukemia type M4, with a trisomy 22 as the only chromosomal abnormality is reported. All six previously published cases with this anomaly had acute myeloid leukemia. The subtype was AMMoL in five patients, and the subtype of the sixth one was not indicated.

Evidence of fibrinogen breakdown by leukocyte enzymes in a patient with acute promyelocytic leukemia

On daunomycin treatment of a patient with promyelocytic leukemia, leukocyte elastase appeared in large amounts in the patient's blood. Also, the plasma fibrinogen was found to be partially degraded to early, X-like, fibrinogen degradation products. These early fibrinogen fragments were isolated and showed a low anticoagulant activity in a thrombin time test. Early fibrinogen degradation products, produced with leukocyte elastase in vitro, have a similar low anticoagulant activity. In contrast, plasmic degradation products inhibit clotting of fibrinogen to a large extent. Although alpha 2-antiplasmin and plasminogen levels were low, antithrombin III levels were not decreased. The low anticoagulant activity of the isolated fibrinogen fragments, the presence of elastase activity in the plasma--both immunological and amidolytic--and the normal levels of antithrombin III suggest that granulocytic enzymes, whose release was enhanced by the cytostatic treatment, were responsible for degradation of fibrinogen in this patient.

The in vitro growth pattern of human bone marrow in methylcellulose stimulated by different concentrations of conditioned medium

The proliferation of human bone marrow in methylcellulose stimulated by various concentrations of conditioned medium (CM) and observed at various intervals was studied. The growth kinetics of granulocytic aggregates was found to differ from monocytic clusters and colonies. Granulocytic aggregates showed a consistent and reproducible dose-response relationship; at day 7, the maximum number of granulocytic aggregates was found at 4% CM. At higher levels, the total number of aggregates decreased, while the number of cells per aggregate increased. The number of macrophage aggregates was far less, depending on the CM concentration. Photographic interval studies showed that at high concentrations of CM, clusters and colonies were formed earlier, but also coalesce to form one colony. Our results suggest that the proliferation kinetics of granulocytic aggregates are complex and preclude simple statements about sensitivity to colony-stimulating activity.

Immunological investigations in aplastic anemia patients

In 53 patients with aplastic anemia (AA) a number of parameters concerning immune responsiveness were analyzed. Severe monocytopenia and B-lymphocytopenia was detected in most patients, especially in those with diffuse lymphocyte infiltration in the bone marrow. T-inducer (OKT4)/T-suppressor (OKT8) ratios were normal. The mean IgG level was significantly decreased. The frequency of specific antibodies to common viruses was comparable to that of healthy donors except for cytomegalovirus to which antibodies were less frequently found. The responding capacity in MLC was normal but patients' lymphocytes were often less stimulating than control lymphocytes. Radioresistant suppressor cells were found in 1 patient. In vitro lymphocyte reactivity to mitogens and antigens was severely impaired, related to the numbers of monocytes present. When allogeneic monocytes were added, mitogen responses could be restored.

The factor VIII ratio in normal and pathological pregnancies

The factor VIII ratio was measured in 102 pregnant women (43 uncomplicated pregnancies, 19 with pre-eclampsia without fetal growth retardation, 8 pre-eclampsia complicated by fetal growth retardation, 12 with only fetal growth retardation and 20 with gestational diabetes). The pathological pregnancies showed a statistically significant elevation of the factor VIII ratio compared to the normal pregnancies. The group of pre-eclampsia complicated by fetal growth retardation showed the most marked increase of the factor VIII ratio. The results are discussed in relation to the hypothesis that the elevated factor VIII ratio is mainly due to the release of factor VIII antigen by various forms of vascular stress.

Teratoma of the lung in a hemophilic patient

We describe a patient with hemophilia A and primary malignant teratoma of the lung. Hemothorax and pseudotumor in hemophilia are rare disorders and can raise many differential diagnostic problems.

Busulphan aplasia in rabbits: a model for human aplastic anaemia

Bone marrow histology plays a crucial role in the clinical diagnosis of aplastic anaemia. The nature of the disease means that few studies are available on the histological changes which occur in the early stages of the development of aplasia. We describe here an animal model which may have some relevance in this respect. Rabbits were chronically exposed to busulphan (BU) to induce aplasia. Sequential histological monitoring of the bone marrow was performed to obtain information about the events preceding full-blown aplasia. There was an early decrease and ultimate disappearance of granulo- and megakaryopoiesis with relative sparing of erythropoiesis which showed severe displasia. Increasing lymphoplasmacytoid infiltrate resembling that seen in human aplasia could be observed in the majority of the animals, together with a decrease of the peripheral lymphocyte number. Lymph nodes and spleen did not show lymphocyte depletion and serum gamma-globulin remained stable. Fibrosis was observed in 50% which is in contrast with human aplasia at diagnosis. In half of the animals there was a rise in MCV, which was not correlated with reticulocytosis or degree of dyserythropoiesis. BU-induced aplasia in rabbits, which resembles long-standing grade II human aplasia in many respects, might be a suitable model for the study of aplastic anaemia due to stem cell defects.

Anti-thymocyte globulin treatment for aplastic anemia

20 patients with severe aplastic anemia were treated with anti-thymocyte globulin (ATG), 6 of them in combination with haplo-identical bone marrow. 7 patients (35%) showed a good clinical response within 6 months; they were off transfusions and had greater than or equal to 0.8 x 10(9)/l neutrophils. ATG had the greatest effect on red-cell production and the least on platelet production. The hematological recovery with ATG could not be predicted from the bone-marrow histology, CFU-c growth, or clinical data. However, patients with strong HLA antibodies seemed to respond more often. The actuarial survival was 55% at 5 years. Under intensive supportive care, even 7 out of 12 non-responders were alive after 1 year. ATG appears to be a useful form of therapy for patients with severe aplastic anemia who are not candidates for bone-marrow transplantation.

Inhibition of CFUE and BFUE by mononuclear peripheral blood cells during chronic benzene treatment in rabbits

Peripheral blood cells from untransfused rabbits that were treated with a moderate dose of benzene during 2 months were cocultivated with autologous and normal bone marrow. In a significant number of experiments, CFUE and BFUE growth of both autologous and normal bone marrow was suppressed. Further experiments showed that this inhibition was associated with adherent mononuclear peripheral blood cells. It is concluded that benzene, an established myelotoxic agent, also induces CFUE and BFUE inhibiting activity in adherent peripheral blood cells.

Anti-thymocyte globulin (ATG) can eliminate platelet refractoriness

Of the 14 patients with aplastic anaemia treated in our hospital with anti-thymocyte globulin (ATG), four were refractory to random platelets before therapy due to the presence of leucocyte antibodies. In contrast to the ten nonrefractory patients in whom no success was obtained, three of the four refractory patients showed haematological improvement after ATG. Additionally, two patients could be substituted again with random platelets. The other two hardly needed platelet-transfusions after ATG, and they were given HLA-compatible platelets. To determine the degree of immunosuppression, these four patients were tested for the presence of antibodies against leucocytes and two endemic viruses, i.e., mumps and rubella virus. Before ATG, all sera reacted with almost the whole leucocyte testpanel. After treatment, the leucocyte antibodies disappeared completely in three patients. In one patient there was no dramatic change. In all patients, however, the antibody-titre against the mumps and rubella viruses remained constant and there was only a slight decrease in total IgG content in the three "suppressed" patients. We conclude that it might be worthwhile to study systematically the selective immuno-suppressive effect of ATG.

111Indium-chloride bone marrow scintigraphy in aplastic anaemia

Bone marrow scintigraphy, using 111Indium-chloride, was performed in 24 patients with acquired aplastic anaemia to investigate: (1) a possible relationship between bone marrow scintigraphy and peripheral blood cell values, (2) a possible relationship between scintigraphy and histology of the bone marrow and (3) the ability to distinguish various aplastic anaemia subtypes with bone marrow scintigraphy. For this purpose a semi-quantitative scoring of scintigraphic results was used. Only a weak correlation was found between the radionuclide studies and blood counts. It appeared that an abnormal 111In-scintigraphic activity in the pelvis was related to an abnormal quality and quantity of haematopoietic tissue. To study a correlation with histological subtype grading, the patients were grouped in 4 categories based on clinical-histological results. Thus it could be demonstrated that the presence of 111In-activity in long bones ('scintigraphic extension') is an important parameter in distinguishing patients who are believed to suffer from a primary stem-cell defect, from patients who may suffer from an auto-aggressive disorder.

Extreme potassium loss in a patient with severe graft versus host disease

A 19-year-old male, suffering from post-hepatitis aplastic anaemia, was transplanted with bone marrow cells from his HLA-identical, MLC non-reactive brother. Haematological recovery ensued, but the patient also developed grade IV graft-versus-host disease (GVHD). In addition to involvement of skin, liver and gut, the kidney seemed affected by GVHD since the patient has hypokalaemia and severe hyperkaluria. Other causes of urinary potassium loss were excluded. The amount of potassium loss correlated well with the severity of the GVH-reaction. Although coagulation disorders prohibited a kidney biopsy, the clinical course suggested GVHD to be the cause of the urinary potassium loss.