Acute respiratory failure in severe hematologic disorders

The development of acute respiratory failure (ARF) in patients with hematologic disorders (HDs) is a life-threatening condition which does not respond well to intensive therapy. We present our experience in the use of intensive therapy for a group of 30 patients suffering from leukemia (21 cases), bone-marrow aplasia (6 cases), or lymphoma (3 cases). Seven had undergone bone-marrow transplantation. All 30 patients were hypoxemic and responded poorly to the administration of high oxygen concentrations via face mask. All were admitted to our intensive respiratory unit (IRU), where 26 received oxygen via mechanical ventilation, and 4 received continuous positive airway pressure (CPAP). Definitive diagnosis was established in 19 (63%) patients. A premortem diagnosis obtained in 8 (26%) cases did not change therapy. The diagnostic accuracy of serology and transbronchial biopsy was low. Of the 6 (20%) patients who recovered from ARF, only 2 were discharged from the hospital. The remaining 24 (80%) patients died in the IRU.

Bone marrow injury in lithographers exposed to glycol ethers and organic solvents used in multicolor offset and ultraviolet curing printng processes

Prompted by referral of a printer with aplastic anemia, a study of possible marrow toxicity of workplace substances was undertaken. Dermal and respiratory exposures to dipropylene glycol monomethyl ether, ethylene glycol monoethyl ether, and a range of aliphatic, aromatic and halogenated hydrocarbons used for offset and ultraviolet cured multicolor printing were documented. Evaluation of seven co-workers revealed normal peripheral blood pictures, but bone marrow specimens demonstrated clear patterns of injury in three while the others had nonspecific signs of marrow effect. These changes could not be explained by known risk factors. The authors conclude that further evaluation of possible bone marrow toxicity resulting from exposure to glycol ethers and ultraviolet curing printing processes is warranted. More generally, we have provided data demonstrating that peripheral blood counts may be an insensitive tool for the study of hematologic toxins acting at the bone marrow level.

Hemocytopenia as initial manifestation of systemic lupus erythematosus. Prognostic significance

In 1960 Rabinowitz and Dameshek emphasized the close relationship between idiopathic thrombocytopenic purpura (ITP) and systemic lupus erythematosus (SLE) and suggested that ITP is often a prodrome of SLE. On the basis of tis observation, the present study was designed to investigate the prevalence of SLE in patients with the initial diagnosis of ITP, autoimmune hemolytic anemia (AIHA), Fisher-Evans' syndrome (F-E) and idiopathic aplastic bone marrow (IABM) and to investigate the salient clinical manifestations and prognosis of these patients. We studied 62 patients, 35 with ITP, 16 with AIHA, 9 with F-E and 2 with IABM. Seventeen developed four or more ARA criteria for SLE within 6 of 14 years after the initial hematologic manfestations (IHM). Mucocutaneous symptoms predominated in all groups. None developed renal failure and only 2 had central nervous system involvement. When these patients were matched by age, sex and duration of illness with 24 SLE patients without hematologic abnormalities, the everity and therapeutic indices of the former showed a significantly (p 0.001) milder course. Eight of the 9 patients that required splenectomy are at present without treatment. SLE patient with IHM have a more benign course which is not worsened by splenectomy.

[Transfusion induced hypersiderosis in aplastic anemia--physiopathology and therapeutic aspects]

Congestive cardiomyopathy and final stage of a liver cirrhosis due to massive overload of iron are often the cause of death in polytransfused patients with aplastic anaemia. With increasing frequency of transfusion the problem of overload of iron becomes more actual. The toxicity of abundant iron is based on various mechanisms of action, which are compiled with the help of literature. Our experiences hitherto made with the intravenous long-term infusion of desferrioxamine are reported. This regimen of therapy is not to be practiced in the long run.

Antithymocyte globulin treatment in patients with aplastic anemia: a prospective randomized trial

We evaluated the efficacy of antithymocyte globulin for the treatment of moderate to severe aplastic anemia in a randomized controlled study. Eleven of 21 patients initially randomized to receive antithymocyte globulin (given intravenously on eight consecutive days) had sustained improvement in hematopoiesis within three months of treatment; none of 21 control patients who received supportive care alone improved (P = 0.0005). Six of 12 control patients who subsequently received antithymocyte globulin improved. Responders had gradual improvement in hematopoiesis, but none recovered completely normal peripheral-blood counts. The severity of bone-marrow failure, age, cause of aplastic anemia, and transfusion history had no apparent bearing on treatment outcome. The interval from diagnosis to antithymocyte globulin treatment correlated inversely with the chance of a treatment response, although this correlation was not statistically significant. These data indicate that antithymocyte globulin is effective in improving hematopoiesis in some patients with aplastic anemia.

Suppression of cytotoxic effect of mitomycin-C by superoxide dismutase in Fanconi's anemia and dyskeratosis congenita fibroblasts

Survival curves were determined for several human diploid fibroblast strains treated with mitomycin-C (MMC) with or without concomitant incubation with superoxide dismutase (SOD). These included cells from patients with Fanconi's anemia (FA), dyskeratosis congenita (DC) a disorder related to FA, Gardner's syndrome (GS) and xeroderma pigmentosum grop C (XPC). Incubation with SOD had no effect on MMC-induced cytotoxicity in the two normal cell strains, XPC or GS. Although GM2053 (FA) and two DC strains showed intermediate sensitivity to killing by MMC similar to XPC and GS, the survival of these cell strains was increased approximately 2-4 times after 0.5 microgram/ml of MMC by concomitant treatment with SOD. Survival of the most MMC sensitive cell strain GM1309 (FA) was sharply increased by adding SOD; survival was enhanced about 15-fold after treatment with 0.1 microgram/ml of MMC. SOD induced no enhancement of survival in MMC treated normal cells at survival levels down to nearly 10(-3). We propose that the hypersensitivity to MMC cytoxicity in FA and DC cells may involve among other factors a deficiency in the inactivation of certain free radical intermediates.

Studies on the in vitro microenvironment in man

In a preliminary manner, the data presented here characterize some features of MSC and their progenitors. The progenitors, at least in chronic myelogenous leukemia, are derived from the neoplastic pluripotent stem cell that also differentiates along lymphoid and myeloid pathways. In addition, we have demonstrated that the precursor for MSC is lacking both the Ia and CALLA determinants. Several antigenic and functional characteristics of the mature stromal cell population have also been identified. Stromal cells express CALLA, synthesize types I, III, and IV collagen, and may express factor VIII associated antigen. It is of interest that fibroblasts do not express factor VIII associated antigen, do not synthesize type IV collagen in measurable quantities, but do express CALLA [9]. Endothelial cells express factor VIII associated antigen, synthesize type IV collagen, but are not CALLA positive. Thus, MSC have some features in common with fibroblasts and others with endothelial cells. The unique characteristics of MSC are that they are transplantable and are derived from a common progenitor with other hematopoietic cells. These features clearly distinguish this cell population from fibroblasts, which are neither transplantable nor derived from the neoplastic clone in CML.

Defective repair of mitomycin C crosslinks in Fanconi's anemia and loss in confluent normal human and xeroderma pigmentosum cells

Crosslink repair of mitomycin C-induced interstrand crosslinks was studied in exponentially growing and confluent normal human, transformed W138CT-1, Fanconi's anemia (FA) and xeroderma pigmentosum (XP) group-A fibroblasts by the assay methods of alkaline sucrose centrifugation, hydroxyapatite column chromatography and S1-nuclease digestion. These three methods demonstrated unequivocally that crosslinking occurred at a rate of 0.13 crosslinks/10(8) Da per microgram per ml mitomycin C (less than or equal to 10 micrograms/ml) and the first half-excision of crosslinks followed the rapid first-order kinetics of 2-3 h half-life in exponentially-growing normal, WI38CT-1 and XP group-A cells. However, the first half-excision was completely defective in three out of the four FA strains tested and severely retarded in an FA strain. These results strongly support our previous observations in different strains of normal human, FA and XP group-A cells. An important new addition is that confluent, otherwise proficient, normal and XP cells almost completely lost the ability of the first, rapid half-excision of mitomycin C crosslinks in their DNA. This probably suggests that the enzyme or regulatory factor responsible for the half-excision, which differs from that for nucleotide excision repair, present constitutively in confluent cells, may be induced or activated only in the cycling cells. However, its relation to a defective FA factor is not clear at present.

T gamma (T gamma) cells suppress growth of erythroid colony-forming units in vitro in the pure red cell aplasia of B-cell chronic lymphocytic leukemia

In vitro studies were performed in two patients with B-cell chronic lymphocytic leukemia who developed pure red cell aplasia (CLL-PRCA). During the active phase of their red cell aplasia, there was a marked reduction in the numbers of erythroid colony-forming units (CFU-E). Unfractionated sera or separated IgG fractions from these patients did not impair CFU-E proliferation from either autologous or allogeneic marrows. Increased numbers of T lymphocytes were present in marrow aspirates of these patients. Analysis of these T cells indicated that 90 and 35%, respectively, bore Fc receptors for IgG (T gamma cells). Removal of T cells by E-rosetting techniques augmented CFU-E growth in CLL-PRCA 10-fold. Similar treatment of normal marrows did not cause similar enhanced growth of CFU-E. Co-cultures of marrow T cells or T gamma cells obtained during the active phase of CLL-PRCA suppressed CFU-E growth from autologous or allogeneic marrows. After achieving drug-induced remission of the PRCA, marrow T cells were no longer inhibitory. In contrast, BFU-E (erythroid burst-forming units) or granulocyte proliferation in diffusion chambers were not suppressed by CLL-PRCA T cells. These findings suggest that the development of PRCA in B-cell CLL may result from suppression of CFU-E proliferation by T gamma cells.

Regeneration of peripheral blood cells following allogeneic bone marrow transplantation for severe aplastic anaemia

We have studied the pattern of regeneration of peripheral blood cells following ABO compatible bone marrow transplantation for severe aplastic anaemia. 18 patients were treated with cyclosporin A and six with methotrexate for post graft immunosuppression. The number of days taken for the neutrophil count to reach 0.5 x 10(9)/l, the lymphocyte count to reach 1.0 x 10(9)/l, the platelet count to reach 100 x 10(9)/l and the reticulocytes to reach 1% was shorter in the CyA treated patients. This finding reached statistical significance for all types of cells except the platelets (neutrophils, P less than 0.001; lymphocytes, P less than 0.02; platelets, P greater than 0.05; reticulocytes, P less than 0.001). The more rapid regeneration of peripheral blood cells in patients treated with cyclosporin A has contributed to reducing the length of time patients are dependent on blood product support in the post transplant period.

Susceptibility of Fanconi's anemia lymphoblasts to DNA-cross-linking and alkylating agents

In order to develop the usefulness of Fanconi's anemia (FA) lymphoblast lines for biochemical and genetic studies, we have determined their sensitivity to a variety of DNA-damaging chemicals. We have adapted a growth inhibiton protocol in which the sensitivity of a cell line is characterized by the drug concentration yielding a 50% inhibiton of growth (EC50). The DNA-cross-linking agents, mitomycin C, nitrogen mustard, melphalan, 1,3-butadiene diepoxide, cis-diaminedichloroplatinum(II), and cyclophosphamide, were all more toxic to four FA cell lines than to five normal lines. Three lines, HSC 72 (FA), 99 (FA) and 230 (FA), had EC50s that were 10 to 20 times lower than that of controls while the fourth line, HSC 62 (FA), had an intermediate EC50. Three nitrosourea compounds were also more toxic to FA cells than to controls. However, 2 normal cell lines (HSC 92 and 93) had nitrosourea EC50s 4 to 7 times lower than the other nine controls and overlapped the sensitivity of the intermediate [HSC 62 (FA)] cell line. The same 2 normal cell lines were also more sensitive than 12 other controls, including FA heterozygotes, xeroderma pigmentosum, and ataxia telangiectasis, to the monofunctional alkylating agents, ethyl methane sulfonate, methyl methane sulfonate, and N-methyl-N'-nitro-N-nitrosoguanidine. Heterogeneity was also found with FA lines. Two FA cell lines (HSC 72 and 230) had EC50s lower than all control lines while one FA line (HSC 99) had an EC50 similar to that of the resistant normal lines. FA and normal cells had nearly the same sensitivity to 4-nitroquinoline-1-oxide and bleomycin. These results demonstrate that FA lymphoblast lines are more sensitive than normal cell lines to all DNA-cross-linking agents examined. These cell lines should therefore be useful for the analysis of DNA cross-link repair and the biochemical defect in FA. We have also found an unexpected sensitivity of some FA and normal lines to monofunctional alkylating agents.

Erythropoiesis in hairy cell leukaemia: a true erythroid failure

A quantitative evaluation of erythropoiesis was carried out in 12 patients with hairy cell leukaemia (HCL). The results were compared with those obtained in eight patients with aplastic anaemia (AA) in order to define the characteristics of erythroid failure in HCL. Discriminant analysis was applied to both haematological and erythrokinetic parameters of the two disease groups. Plasma iron concentration and MCV were significantly higher in AA, and allowed a perfect separation of the patients. As regards erythrokinetics, values of ineffective erythropoiesis and peripheral haemolysis were able to separate completely the two disease groups, being significantly lower in HCL than in AA. A true erythroid failure was the peculiar erythrokinetic pattern of HCL. This conclusion allows one to speculate on the nature of the stem cell damage in this disease.

Aplastic anemia: biology and treatment

Aplastic anemia is characterized by decreased bone marrow function with inadequate production of erythrocytes, granulocytes, and platelets. Marrow failure may be caused by absence of or defects in hematopoietic stem cells, abnormalities of the bone marrow microenvironment, ineffective cell-to-cell interactions, or immune disorders. Although most patients with aplastic anemia have normal immunity, some have abnormalities of T- and B-lymphocytes. Rare patients have an immune cause of marrow failure. Treatment of aplastic anemia involves blood transfusions and withdrawal of potential causal factors. Efforts to stimulate hematopoiesis with androgens, corticosteroids, and other drugs have been largely unsuccessful. Some patients may recover after treatment with antithymocyte globulin or other immunosuppressive agents. Bone marrow transplantation is the preferred treatment for patients with severe aplastic anemia who have a human-leukocyte-antigen-identical related donor. Transplants of hematopoietic stem cells obtained from alternative sources, such as fetal liver cells or stem cells from long-term, in-vitro cultures, also may be useful.

Regulation of human megakaryocytopoiesis. An in vito analysis

We have recently described an assay system for human peripheral blood megakaryocyte colony-forming unit cells (CFU-M) using an anti-platelet glycoprotein antiserum probe to define megakaryocyte colonies grown in vitro. This system was applied to study the nature and regulation of human bone marrow CFU-M. In the absence of a specific megakaryocyte growth-promoting factor, 12.4 +/- 3.0 (means +/- SEM) megakaryocyte colonies were cloned per 5 X 10(5) cells cultured. Colonies were present after 6 d of incubation reaching peak numbers between days 10 and 14 and slowly decreasing thereafter. Erythropoietin in concentrations of up to 4 U/ml failed to augment colony numbers. Also failing to enhance megakaryocyte colony plating efficiency were media containing burst-promoting activity and colony-stimulating activity. A medium conditioned by human embryonic kidney cells, which has been previously demonstrated to contain thrombopoietin, also had no effect on megakaryocyte colony numbers. In contrast, sera from three patients with severe aplastic anemia produced significant enhancement of CFU-M-derived colony formation in vitro. Both the number of megakaryocyte colonies present and the number of megakaryocytes per colony were increased in proportion to the final concentration of aplastic anemia serum. In the presence of 10% aplastic anemia serum, cultured megakaryocyte colony numbers were linear with respect to the number of bone marrow mononuclear cells plated suggesting a clonal origin of each of the colonies. This in vitro assay for bone marrow CFU-M is a reliable means by which to study the regulation of human megakaryocytopoiesis. Initial data suggest that megakaryocyte production is stimulated by a factor detectable in aplastic anemia serum that may be distinct from other known hematopoietic stem cell regulators.

[Pathophysiology of aplastic anemia and its treatment with methenolone enanthate]

For the development of an aplastic anaemia a large number of causes is taken into consideration. In our own clinical material of 26 patients in 15 patients none of the up to now known noxae could be established. Recently in the clarification of the picture of the disease important pathophysiological realizations were got. In these cases disturbances of the stem cell compartments, effects through the matrix of the haematopoietic cells and immunological processes have been recognized as significant. --Own investigations concerning the therapy with the anabolic metenolonenanthat (Primobolan-S) yielded approximately the same large number of therapeutic failures and patients with a good result of the treatment or a partial remission in 15 idiopathic and 11 toxically conditioned anaemias. In the partial remissions in most cases a thrombocytopenia continued existing. A therapy lasting at least two months is necessary in order to estimate the result of the therapy. At the present time cannot yet be predicted on which conditions the use of anabolics will be successful.

Aplastic anemia: lack of inhibitory effect of bone marrow lymphocytes on in vitro granulopoiesis

Prompted by previous reports that in certain patients with aplastic anemia, cell-mediated autoimmune suppression of myeloid stem cell proliferation may be demonstrable in vitro, we studied the effects of bone marrow lymphocytes from 18 patients with myeloid aplasia on the proliferation of committed granulocytic-monocytic progenitor cells (CFU-C). When assayed in soft agar cultures, marrow suspensions from 10 patients with aplastic anemia contained significantly fewer viable CFU-C than similar cell preparations from control subjects. To deplete marrow cell suspensions of lymphocytes, we employed rabbit anti-human thymocyte serum (ATS), which after multiple adsorptions exhibited marked cytotoxicity for human B and T lymphocytes but had negligible effect on normal CFU-C proliferation. Preincubation of marrow samples from 12 patients with ATS and complement resulted in no inhibition or enhancement of CFU-C growth. In further experiments, marrow cells from 8 patients were incubated with marrow from control subjects prior to CFU-C culture. No suppression of donor CFU-C proliferation was observed in any of these studies, and in 4 cocultures, mixture of the 2 marrow suspensions resulted in stimulation of CFU-C growth. Using these assays, we detected no evidence of cell-mediated inhibition of CFU-C proliferation in any of the 18 patients that we evaluated. Our data support the conclusion that in the majority of patients with aplastic anemia, an absolute deficiency of hemopoietic stem cells is present within the marrow that does not appear to be effected or sustained by suppressor lymphocytes. Whether the reduction of viable stem cells is the cause or the consequence of the process that leads to marrow failure remains unknown.

The effect of granulopoietic stress in mice with "latent" bone marrow failure

We treated mice with high-dose busulfan to produce a residual or "latent" hematopoietic injury characterized by persistent normal or near-normal peripheral blood counts and marrow cellularity but moderate to marked reduction in hematopoietic stem cells. Control and "latent" mice were then challenged with glucan, a granulopoietic stimulant. We found that glucan administration induced a comparable increase in granulocytic differentiation in control and "latent" mice. This differentiational expansion was not accompanied by a further depletion of pluripotent hematopoietic stem cells. Our results fail to demonstrate competition between self-renewal and differentiation at the level of the CFUS, at least in this model. Stimuli for granulopoiesis act primarily on more distal, committed populations which are apparently unaffected by prior exposure to busulfan.

beta 2-Adrenergic stimulation of erythropoiesis in busulfan treated mice

The capability of chronic beta 2-adrenoceptor activation to effectively stimulate erythrocyte production in vivo was investigated in mice which had been treated with the hematopoiesis inhibiting agent busulfan. A relatively low dose (5 mg/kg i.p.) of busulfan produced moderate depression of erythropoiesis 10 days after a single injection, as determined by 59Fe-incorporation into erythrocytes. Administration of albuterol (1 mg/kg s.c. twice daily), a selective beta 2-adrenergic agonist, significantly enhanced erythropoiesis for 5--10 days after the injection of busulfan. In a long-term study with albuterol at the same dose a significant increase in hematocrit values as well as in the circulating erythrocyte mass was found in busulfan (5 mg/kg i.p. weekly) treated mice when compared to saline-busulfan treated control mice. Simultaneous injections of the beta-adrenergic blocking agent propanolol (4 mg/kg i.p.) diminished the effect of albuterol on erythropoiesis. Albuterol at a lower dose (0.1 mg/kg) had no significant effect on erythrocyte mass. In view of recent findings, which have shown that the proliferation of the pluripotent hemopoietic stem cell pool is blocked by busulfan, it is concluded that the main site of beta 2-adrenergic action on erythropoiesis is on the erythroid committed stem cell pool. In addition, enhanced release of erythropoietin from the kidney following the application of albuterol may contribute to beta 2-adrenergic stimulation of erythropoiesis.

A proliferative defect of marrow cells in experimental chronic hypoplastic marrow failure (aplastic anaemia)

Marrow cells from control mice and mice with chronic hypoplastic marrow failure (CHMF, aplastic anaemia) were grown in tissue culture and growth was assessed by measuring the number of cells/colony and uptake of 3H-thymidine/colony. Cells from mice with CHMF showed impaired proliferation in response to colony stimulating factor. Mixing experiments suggested that the impairment of proliferation was not dut to alteration in suppressor or helper cells but to an intrinsic lesion of the marrow cells themselves.

Bone-marrow microenvironment defect in congenital hypoplastic anemia

An abnormal bone-marrow microenvironment has been thought to have an important role in the pathogenesis of aplastic and hypoplastic anemia in some patients, but direct evidence of such a defect has not been found. We have investigated the pathogenesis of chronic anemia in a young woman. Her bone-marrow cells, obtained by means of aspiration, showed exuberant erythroid growth in methylcellulose despite marked erythroid hypoplasia. The erythroid nature of the colony growth was further confirmed through measurement of heme synthesis and messenger RNA-globin accumulation in a liquid-culture system. In contrast, when whole bone fragments were similarly cultured, no appreciable hemoglobin synthesis was observed. The experimental evidence suggests that, in this patient, hypoplastic anemia resulted from an unfavorable microenvironment.

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.

Pathogenesis of the anemia of Shay Chloroleukemia

The pathogenesis of anemia of the Shay chloroleukemia (SCL) was studied in rats following SC, IP and IV inoculation of chloroma cells. Little difference in survival was noted regardless of the route of inoculation. A decrease in hamatocrit occurred in all SCL rats during approximately the final 48 hours of the disease; however, the anemia was more severe in SC- and IP-inoculated terminal rats than in SCL rats inoculated IV. A reduction in the numbers of normal cellular elements was noted in the femoral bone marrow of most terminal rats studied which was found to correlate inversely with the leukemic blast cell content of the marrow. No correlation was observed between the erythroblast content of the marrow and the degree of anemia. The number of erythroblasts varied from greatly reduced to normal in terminal SCL rats despite severe anemia. Moreover, the greatest reduction of both normal marrow cellularity and erythroblast numbers was observed in IV inoculated rats which consistently displayed the highest hematocrits in the terminal stage of the disease. Thus, the terminal anemia appears to be due primarily to excessive red cell loss. The decrease in erythroblasts, when observed, was most striking in the orthochromatophilic and polychromatophilic stages of erythroid maturation.

Bone marrow transplantation for severe aplastic anaemia

An eight-year-old girl with severe acquired aplastic anaemia received a bone marrow transplant from her 11-year-old brother. The bone marrow graft is firmly established, but the patient has mild chronic graft versus host disease affecting liver and skin. The indications for bone marrow transplantation in aplastic anaemia are discussed.