Cataract formation after bone marrow transplantation

OBJECTIVE

To evaluate the incidence, time course, and factors associated with cataract formation in bone marrow transplant recipients.

DESIGN

Prospective cohort study.

SETTING

University Hospitals, Basel, Switzerland.

PATIENTS

197 patients treated with allogeneic or autologous bone marrow grafts at least 180 days before the start of the study.

INTERVENTION

Three regimens for bone marrow transplant were used: 74 patients received single-dose, total-body irradiation (TBI), 90 patients received fractionated TBI, and 33 received chemotherapy alone.

RESULTS

Three and one half years after single-dose TBI, 51 of the 74 patients (69%) were alive and cataracts had developed in all of these 51 patients. Cataracts developed in 18 of the 90 (20%) patients treated with fractionated TBI, with an 83% (95% CI, 63% to 100%) risk for lens opacification at 6 years. Cataracts developed in only 1 of the 33 (3%) patients treated with chemotherapy alone. Incidence of cataracts is higher and lens opacification occurs earlier after single-dose TBI than after fractionated TBI (P < 0.01). With Cox regression analysis, the use of irradiation (relative risk, 21.0), the mode of irradiation (relative risk, 7.4), and the use of steroid treatment (relative risk, 2.9) for more than 3 months after bone marrow transplantation increased the risk for cataract formation. In contrast, age, sex, and chronic graft-versus-host disease did not influence the rate of cataract development. The probability of requiring cataract surgery after 6 years was 85% (CI, 75% to 95%) for the patients treated with single-dose TBI and 20% (CI, 0% to 49%) for those prepared with fractionated irradiation.

CONCLUSIONS

Patients treated with TBI, regardless of fractionation, are likely to have cataracts within 10 years, and some will need surgical repair. Long-term steroid treatment accelerates cataract formation. Preventive measures, such as lens shielding during TBI, should be considered.

Colony growth in cultures from bone marrow and peripheral blood after curative treatment for leukemia and severe aplastic anemia

The recovery of colony-forming cell numbers after curative treatment for leukemia and severe aplastic anemia (SAA) was studied. We examined 191 patients (85 acute myeloid leukemia [AML], 48 acute lymphocytic leukemia [ALL], 32 chronic myeloid leukemia [CML], 17 SAA, and nine myelodysplastic syndrome [MDS]) who were in hematologic remission 6 months to 13 years after either curative chemotherapy (n = 69) or allogeneic bone marrow transplantation (BMT) (n = 122) by culturing their precursor cells from bone marrow (BM) (n = 548) and peripheral blood (PB) (n = 529) in methylcellulose. Thirty-six BM donors and 25 PB donors served as controls. BM colony-forming cell numbers were abnormally low in all patients (p < 0.002) irrespective of underlying disorder and type of treatment (chemotherapy or irradiation). These numbers did not normalize with time--colony-forming cells were still strongly reduced up to 10 years after therapy, whether or not the patient had received an allogeneic bone marrow graft (p < 0.002). We also compared patients who remained in stable hematologic remission with those who later relapsed (6 months to 2 years after treatment). BM colony-forming cell numbers were significantly lower in patients who subsequently relapsed (p = 0.004). In contrast to BM cultures, we found normal colony-forming capacity by PB precursors in all patients. We conclude that (1) after chemotherapy or BMT, colony-forming cell numbers of BM in culture are permanently reduced; (2) this defect is probably due to a dysfunction of the BM environment rather than to a numerical reduction of the precursor cell pool; and (3) very low colony-forming capacity may be related to relapse.

Relapse of aplastic anaemia after immunosuppressive treatment: a report from the European Bone Marrow Transplantation Group SAA Working Party

This study was designed to determine the incidence of relapse and factors predictive for relapse in 719 patients with severe aplastic anaemia (SAA) after immunosuppressive treatment (IS). Patients developing myelodysplasia or acute leukaemia after IS, and patients receiving a transplant, were excluded from this analysis. Response was defined as reaching complete independence from transfusions, relapse was defined as becoming again transfusion dependent. This criteria was validated by similar figures when using other 'relapse criteria' such as drop in neutrophil or platelet counts. Of 358 patients responding to IS. 74 patients relapsed after a mean time of 778 d after treatment. The actuarial incidence of relapse is 35.2% at 14 years after IS. The risk for relapse was higher in patients responding within 120 d from IS (48%) compared to patients responding between 120 and 360 d (40%) and only 20% for slow responders (> 360 d from IS) (P < 0.00001). In multivariate analysis this factor still proved significant (P < 0.0001). The mean time between diagnosis and treatment was significantly longer in patients relapsing compared to patients who did not relapse (260 v 134 d, P = 0.037). Relapse was not predicted by the severity of the disease, age, and sex. In 39 of the 74 relapsing patients a second response could be achieved. Responses after relapse were associated in univariate analysis with early response to previous IS and early occurrence of relapse. The actuarial survival of patients not relapsing is significantly better than survival of patients relapsing (79.8% v 67.1%, P = 0.0024). However, the actuarial survival of 39 relapsing patients who responded again to IS was similar to patients not relapsing (86%) and significantly better than in 35 patients not reaching a second response after relapse (49.3%, P = 0.0015). This study indicates that relapse is a relevant problem in the treatment of aplastic anaemia, and does have an impact on overall survival. Prospective studies of immunosuppressive regimens, looking at responses, should also address this problem in the future.

Increased colony growth in peripheral blood cultures from patients with ALL depends on immunological subtype

The proliferative capacity of precursor cells in bone marrow and peripheral blood of 19 patients with acute lymphoblastic leukaemia (ALL) at diagnosis was studied and results were compared with the immunophenotype of the leukaemic population. Bone marrow proliferative capacity in these patients was strongly diminished, low or absent, independent of the immunophenotype, compared with control values (p < 0.0002). In contrast, the growth pattern in peripheral blood cultures from the same patients varied widely according to the subtype of ALL: whereas in patients with undifferentiated ALL [TdT+, HLA-DR+, CD19+ or-, CD10-, (n = 4) or CD7+, CD5+, CD1-, CD4- and CD8- (n = 1)] PB had strongly reduced proliferative capacity compared with control (p < 0.05), there was excess growth of normal neutrophil and erythroid colonies in BP cultures from patients with a more mature immunophenotype of either B-[CD10+, (n = 11)] or T [CD1+, CD4+ and/or CD8+, (n = 3)] phenotype. This phenomenon was only seen in patients who had circulating lymphoblasts: If their number was low, growth was so prolific that single colonies could not be identified. In the presence of a high blast count, colony growth was less prolific--probably due to a "dilution" effect--but still higher than normal (p < 0.05). We conclude that, in relatively mature ALL of the B- and the T-cell line, the presence of circulating lymphoblasts is associated with increased PB proliferative capacity.

Levels of soluble stem cell factor in serum of patients with aplastic anemia

Aplastic anemia (AA) is a rare bone marrow (BM) disorder characterized by an unexplained failure of hematopoietic precursors to proliferate. In vitro growth of AA BM cells can be improved by the addition of the hematopoietic growth factor SCF (stem cell factor), which suggests that deficiency of SCF may be one of the underlying causes of the disease. In this study, we measured the concentration of SCF in sera of patients with severe AA. One hundred twenty-eight serum samples from 32 patients, at diagnosis and following therapy, were analyzed. Before treatment, SCF levels varied between 0.33 and 6.1 ng/mL; no correlation between hematopoietic function and SCF serum levels was apparent. Therapy with antilymphocyte globulin (ALG) or bone marrow transplantation (BMT) did not result in a recognizable pattern of changes in SCF levels. However, serum concentration of SCF in many patients with AA was at the low range of control serum levels determined in healthy blood donors. Of 128 AA serum samples tested before and after therapy, 107 were below the mean normal value of 3.3 ng/mL, including 26 samples below the minimum normal value of 1.3 ng/mL, as estimated in 267 controls. We also found that SCF levels in peripheral blood serum correlate well with factor concentrations in the BM plasma. Clinical observations suggest that higher SCF serum levels are often associated with a better clinical status of the patients in terms of survival and transfusion requirements. The data indicate that a deficient production of soluble SCF may contribute to AA in some patients; thus, suggesting a potential therapeutic benefit of SCF in this disorder.

Cytokine serum levels during treatment with high-dose recombinant human IL-3 in a patient with severe aplastic anemia

A 37-year-old woman with severe aplastic anemia (SAA), who had relapsed 6 years after antilymphocyte globulin therapy, was treated with intravenous recombinant human IL-3 (4 micrograms/kg/d) for 21 days. Subsequently, long-term therapy with subcutaneous rhIL-3 at the highest dose level tested so far (16 micrograms/kg/d) was initiated in order to maintain growth-factor response. Therapy was discontinued on day 73 due to progressive thrombocytopenia and increased petechial bleeding. Both treatment schedules resulted in a transient increase in leukocytes (twofold) due to an increase in monocytes, neutrophils, and eosinophils. RhIL-3 had no effect on hemoglobin values or platelet counts and only marginally improved colony formation of bone marrow CFU-GM in response to rhGM-CSF. Side effects of both treatment schedules were mild and did not exceed WHO grade II. Steady-state serum concentrations of IL-3, which are able to stimulate hematopoiesis in vitro (i.e. > 1 ng/ml), were achieved by both low- and high-dose treatment, although high-dose treatment resulted in markedly higher serum levels of IL-3. On measuring cytokine serum levels (neopterin, IL-1 beta, IL-6, sIL-2R, GM-CSF, TNF-alpha, IFN-gamma) we noticed a different cytokine pattern with both treatment modalities, resulting in a moderate induction of TNF-alpha and IFN-gamma during low-dose, intravenous treatment, whereas during subcutaneous, high-dose treatment a profound increase of IL-6, sIL-2R, and, to a lesser extent, neopterin was detected. These results in a single patient with SAA indicate that further studies on IL-3 serum levels and IL-3-induced secondary cytokines in a larger group of patients are needed to optimize growth-factor treatment and to better understand the in vivo biological activity of IL-3.

Gender and response to antilymphocyte globulin (ALG) for severe aplastic anaemia

We have evaluated the speed of haematological recovery in 103 severe aplastic anaemia (SAA) patients treated with antilymphocyte globulin (ALG) and followed at our institution for 3-15 years. We found that haemopoietic recovery was significantly delayed in six girls under the age of 10 years. This slow recovery in girls might be explained by their relative inability to release haemopoietic growth factors, granulocyte colony stimulating activity and burst promoting activity, compared to all other sex and age groups. This defect is not explained by disease severity at presentation and thus indicates a functional abnormality of monocytes/macrophages and T-lymphocytes in addition to the deficiency of haemopoietic stem cells. In a multivariate analysis, low factor production and low pretreatment reticulocyte counts turned out to be strong predictors of slow haemopoietic recovery. We conclude that young girls have a particular form of SAA characterized by low haemopoietic factor production and delayed recovery after ALG. They are preferential candidates for early bone marrow transplantation or, if they are not eligible, for treatment with recombinant human haemopoietic growth factors.

[Polycythemia: primary or secondary? The differential diagnostic value of stem cell cultures]

Cultures of hematopoietic precursor cells can be helpful in differentiating between primary polycythemia (polycythaemia vera, PV) and reactive secondary polycythemia: in PV erythroid precursors form hemoglobinized colonies in the absence of added erythropoietin (epo) (= endogenous erythroid colonies), whereas in normals and in patients with secondary polycythemia, formation of erythroid colonies is dependent on added epo. We have performed cultures of peripheral blood precursors from 132 patients with elevated hemoglobin in the presence/absence of added epo. In 48/132 patients we assumed that PV was the cause of polycythemia. In 80/132 patients no endogenous colonies appeared and the polycythemia was judged secondary. 23 PV patients were examined repeatedly. In 18 of them the first diagnosis was confirmed by subsequent cultures; in 5 cases endogenous colonies, which had been present in the first cultures, were no longer detectable. A questionnaire on the subsequent clinical course was sent to 108 treating physicians. 77 questionnaires were answered correctly and returned. In 86% of these patients, our culture diagnosis of PV was either confirmed or another myeloproliferative disorder had been found as a cause of endogenous colonies. In 14% our diagnosis of PV had been false positive. On the other hand, our diagnosis of secondary polycythemia was confirmed in 85% of the patients; its most frequent cause was cigarette smoking and chronic bronchitis and only rarely was it associated with heart or kidney disease. 5/77 patients had persistently elevated Hb without an evident cause, and in 3/77 the Hb normalized spontaneously.(ABSTRACT TRUNCATED AT 250 WORDS)

[The pathophysiology of aplastic anemia]

It is the conventional opinion that acquired aplastic anaemia is a heterogeneous disease including basically different conditions, such as idiopathic or virus induced pancytopenia, toxic-allergic marrow damage or autoimmunity. Here, an alternative concept is proposed, according to which aplastic anaemia is one disease, but multifactorial in all patients, apparent differences being due to the relative prevalence of one or the other pathological component in individual patients. Bone marrow from patients in the severe phase of aplastic anaemia does not grow in culture and is therefore not suitable for experimentation. Alternatively, bone marrow from patients who have resumed some degree of autologous bone marrow function, but still have residual signs of the disease after non-invasive therapy, offers the possibility to study pathological mechanisms in vitro. The majority of experiments presented have been done in such patients, assuming that their status of disease in some way reflects the original, more serious pretreatment condition. Three major pathophysiological components will be discussed, and it will be proposed how these factors act in concert to cause or aggravate aplasia.

Human serum stimulates the production of G-CSF, IL-1, IL-6 and IL-8 by human peripheral blood leucocytes

Human serum induces human peripheral blood leucocytes (PBL) to release an activity stimulating neutrophil colony formation (G-CSA) from human bone marrow cells. By titrating individual growth factors and using specific neutralizing antibodies we showed that: human serum contains very low levels of G-CSF which are by themselves insufficient to stimulate myeloid colony formation in primary human bone marrow cultures and cannot account for the serum releaser activity; that although no detectable levels of IL-1, IL-2, IL-3, IL-4, IL-6 or IL-8 are found in the serum, anti IL-1 antibodies partially block the release of G-CSA when added early during PBL incubation; that PBL incubated in the absence of serum for 2 d produce small amounts of IL-1, IL-6, IL-8 and G-CSF and this is increased 6-16 fold in the presence of human serum; and that the neutrophil colony-stimulating activity released by PBL incubated with human serum is G-CSF.

Morphology in patients with severe aplastic anemia treated with antilymphocyte globulin

One hundred and seventeen patients with severe aplastic anemia (SAA) were treated at our institution between 1976 and 1990 with antilymphocyte globulin (ALG) therapy. Seventy-nine (68%) are alive and probability of survival at 14 years, according to Kaplan and Meier, is 62% +/- 12%. Twenty-six patients developed a late clonal complication: 11 had a myelodysplastic syndrome (MDS) and 17 had paroxysmal nocturnal hemoglobinuria (PNH); two patients had both. The cumulative risk at 10 years is 42%. The development of MDS/PNH after SAA directly affects survival. The probability of being alive at 14 years is 81% +/- 10% for patients with stable disease and 36% +/- 13% for those with clonal evolution (P = .001). To look for predictive signs, we reevaluated peripheral blood and bone marrow cytomorphology at presentation, during regeneration, and in remission. We examined the peripheral blood values for hemoglobin, reticulocytes, granulocytes, thrombocytes, mean corpuscular volume (MCV), and fetal hemoglobin, as well as bone marrow for cellularity, erythropoiesis, myelopoiesis, and megakaryopoiesis. ALG therapy induces slow and incomplete recovery. Although in "remission," ALG patients have lower hemoglobin values, higher reticulocyte counts, lower granulocyte and platelet values, and a higher MCV and fetal hemoglobin than normal controls. They retain a reduced number of megakaryocytes and a persistence of atypical monocytes in bone marrow morphology as stigmata of their disease. Patients with late clonal complications show distinct morphologic abnormalities: patients with PNH have higher MCVs, higher granulocyte and reticulocyte counts, and more dyserythropoiesis at diagnosis and a lower hemoglobin with an increased proportion of erythroblasts in the bone marrow in "remission." Patients who later developed MDS are not different from the total patient population at diagnosis. After therapy, these patients are characterized by the presence of ring sideroblasts and atypical monocytes during regeneration and by a persistent increase in MCV, a higher fetal hemoglobin, lower granulocyte values, and megakaryocytic dysplasia during "remission." Thus, routine morphologic follow-up examination of blood and bone marrow can discover patients at risk for late hematologic complications after ALG therapy.

Suspected distinct activation pathways of human lymphocytes induced by antilymphocyte globulin and anti-CD3 monoclonal antibody result in different secretion of hematopoietic colony-stimulating activities

We evaluated the activation sequence of peripheral blood lymphocytes from healthy donors using different mitogens, including antilymphocyte globulin (ALG), anti-CD3 monoclonal antibody (OKT3), and phytohemagglutinin (PHA). Blood mononuclear cells stimulated by ALG, OKT3 and PHA incorporated 3H-thymidine in the same way. When enriched T cells were tested in the presence of interleukin-1 alpha (0 to 100 U/ml, incorporation of 3H-thymidine was greater in those cells stimulated by ALG than by PHA. OKT3 did not activate enriched T cells. Thymidine incorporation was reduced to less than 50% of maximum concentrations by the addition of 10(-7) mol/1,25-dihydroxyvitamin D3 (vit D3) in PHA- or OKT3-activated cells. However, the inhibitory effect of vit D3 was not apparent in ALG-activated cells. Production of granulocyte-macrophage colony-stimulating factor and interleukin-3 by lymphocytes upon activation was consistently higher when cells were treated with ALG or PHA than with OKT3. Taken together, the data indicate that there appear to be distinct functional mechanisms between ALG- and OKT3-induced lymphocyte activation that lead to characteristic immunohematologic events.

Stem cell factor stimulates the in vitro growth of bone marrow cells from aplastic anemia patients

Aplastic anemia (AA) is a rare human bone marrow disorder of unknown etiology manifested by a strongly impaired growth of hematopoietic precursors. In this study, we examined the ability of recombinant human stem cell factor (SCF) to stimulate proliferation in vitro of bone marrow cells from 15 AA patients. All patients had been previously treated with antilymphocyte globulin (ALG). SCF, in combination with erythropoietin (Epo), interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), and granulocyte colony-stimulating factor (G-CSF), increased the number of hematopoietic colonies formed in a semisolid medium by AA marrows. Maximal colony numbers reached 30% of the numbers observed with normal bone marrow cells. Proliferation of AA cells cultured in a liquid medium containing SCF together with Epo, IL-3, GM-CSF, and G-CSF approached 70% of the control level, as measured by 3H-thymidine incorporation. The effect of the combination of SCF with the other growth factors was more than 10 times stronger than that of the growth factors alone. The most marked effect of SCF was on the generation of erythroid colonies by precursor cells. The results demonstrate synergism between CSF and other hematopoietic growth factors, resulting in the most efficient stimulation of the in vitro growth of AA bone marrow cells described to date. Use of SCF, either alone or in combination with other factors, may be of potential value in treatment of AA.

Recombinant human granulocyte-macrophage colony-stimulating factor accelerates neutrophil and monocyte recovery after allogeneic T-cell-depleted bone marrow transplantation

In a prospective randomized study, five European transplant centers compared recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; mammalian glycosylated) with placebo. rhGM-CSF was administered in a dose of 8 micrograms glycoprotein (5.5 micrograms protein)/kg/d, as a continuous intravenous (IV) infusion for 14 days, starting 3 hours after bone marrow infusion. Fifty-seven patients entered and completed the study. Median age of the recipients was 34 years (range, 17 to 51 y). All donors were HLA-identical, MLC-nonreactive siblings. Marrow grafts were depleted of T lymphocytes either by counterflow centrifugation (n = 42) or by immunological methods (n = 15). Twenty-nine patients received rhGM-CSF and 28 patients placebo. The leukocyte count and the absolute neutrophil count were significantly higher in the rhGM-CSF-treated group from day +9 to day +14 after bone marrow transplantation (BMT). This was also true for the monocyte count from day +12 to day +21. Early neutrophil (greater than 0.1 and greater than 0.3 x 10(9)/L) and early leukocyte (greater than 0.3 and greater than 0.5 x 10(9)/L) recovery was significantly faster for the patients given GM-CSF. The incidences of graft-versus-host disease (GVHD) and transplant-related mortality were not different in both groups. However, the number of bronchopneumonias was significantly lower in the rhGM-CSF-treated group (P = .03). Long-term follow-up showed a trend to better overall disease-free survival at 2 years and a trend to a lower relapse risk in patients treated with rhGM-CSF. This study shows that rhGM-CSF significantly increases neutrophil and monocyte counts during periods of 6 to 10 days in the second and third week after BMT. This shortened period until myeloid cell recovery after transplantation resulted in a decreased number of pneumonias, without an increase in incidence of GVHD or relapse.

[Health status and late complications following allogeneic bone marrow transplantation. A review]

Better results following bone marrow transplantation (BMT) have increased the number of patients in longterm follow-up. Health status and late effects are therefore of increasing interest. We discuss here the incidence and follow-up of late complications after allogenic BMT. Any conditioning regimen including TBI in postpubertal women introduces a postmenopausal status. In contrast, normal function is found after BMT without irradiation. In men, there is usually permanent azoospermia after TBI but not following chemotherapy alone. Thyroid dysfunction after BMT with TBI has been reported in about 40% of patients. In most of them compensated hypothyroidism with elevated TSH is found. BMT with TBI induces growth retardation in children. Decreased growth hormone levels are observed and substitution can induce normal height development. Interstitial pneumonitis (IP) is a major cause of death. It occurs on average three months after BMT but late onset IP's are increasingly reported. Cataracts are common after BMT. The risk of cataracts in patients given single dose TBI attains 80-100% after four years. Under treatment with cyclophosphamide alone, the risk of lens opacification is less than 20%. So far, patients treated with fractionated TBI have not developed more cataracts than those treated with chemotherapy alone. Impaired renal function is common early post-transplant. Risk factors include cyclosporine (CSA) nephrotoxic antibiotics and antifungal drugs. So far, few secondary malignancies have been reported in humans after BMT. However, actual observation time is still too short for final evaluation. Prevention or treatment is instituted for common complications. It is expected that other types of tissue damage will be recognized.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum concentrations of immunoglobulins and of antibody isotypes in bone marrow transplant recipients treated with high doses of polyspecific immunoglobulin or with cytomegalovirus hyperimmune globulin

The kinetics of immunoglobulins (Ig) and antibodies were followed in 10 bone marrow transplant recipients who received either high doses (0.5 g/kg body weight) of polyspecific intravenous Ig (HD-IVIG) weekly or cytomegalovirus hyper-Ig (CMV-IVIG, 0.1 g/kg body weight) every 3 weeks. In the HD-IVIG group, the mean total IgG concentration more than tripled and similar significant increases were seen for IgG1 and IgG2. IgG antibodies to CMV showed a marked increase in the HD-IVIG and a less pronounced rise in the CMV-IVIG group. IgM antibodies to CMV were present initially or became detectable in five patients, unrelated to the IVIG preparation. HD-IVIG induced a significant increase of IgG antibodies to streptococcal group A carbohydrate (A-CHO) and to smooth strain lipopolysaccharides (LPS) but not of antibodies against lipid-A. When the Ig treatment was discontinued, levels of total IgG and of IgG antibody to CMV decreased with an apparent half-life of 30 days. Both IVIG preparations were well tolerated and had no negative feedback on total Ig and on specific antibody production or other antimicrobial defence mechanisms. In patient nos. 4 and 10 who developed severe graft-versus-host-disease, transient serum Ig peaks including several Ig isotypes appeared after day 14. In patient no. 10 this peak contained an IgG antibody to H. influenzae type b (Hib), and IgM antibodies to CMV, Hib, A-CHO and LPS. This study clearly shows that serum concentrations of Ig isotypes, subtypes and specific antibodies, depend on at least four factors: total amount and composition of Ig infused, consumption, catabolism and endogenous production.

The pathophysiology of aplastic anemia

No single cause can explain aplastic anemia. Two major factors are involved: An intrinsic derangement of hemopoietic proliferation capacity that is essentially compatible with life, but has to be considered a premalignant condition. This primarily diseased tissue can be destroyed by immune mechanisms in an attempt to achieve self-cure. Therefore, immunosuppressive therapy can mitigate this immune reaction but leaves the patient with a poorly proliferating bone marrow that is prone to late complications. The clinical presentation and course depend on the balance of these two major factors: If the immune reaction is strong, acute severe aplasia occurs, whereas in patients with a weak immune reaction the disease will present itself rather as chronic pancytopenia with myelodysplastic traits. Co-involvement of environmental cells in the disease process is an additional factor. Poor production of hemopoietic growth factors may aggravate aplasia and poor immune competence may allow abnormal clones to proliferate. All these pathophysiological factors are genetically determined.

[Aplastic anemia combined with an autoimmune disease (eosinophilic fasciitis or glomerulonephritis)]

We describe 3 patients with aplastic anemia and an autoimmune disease. Two had eosinophilic fasciitis and 1 glomerulonephritis. In all patients both diseases were successfully treated by immunosuppressive therapy. Pathophysiological aspects of this association are discussed.

High-dose recombinant human erythropoietin for treatment of anemia in myelodysplastic syndromes and paroxysmal nocturnal hemoglobinuria: a pilot study

In a dose escalation study we tested the feasibility and tolerance of high-dose recombinant human erythropoietin (r-HuEPO) therapy in four patients with ineffective erythropoiesis due to myelodysplastic syndromes (MDS) or paroxysmal nocturnal hemoglobinuria (PNH). Recombinant human EPO was administered i.v. with an initial dose of 50 U/kg body weight (BW) three times per week. The dose was increased by steps of 25 or 50 U/kg bW with intervals of 1-4 weeks up to a maximum dose of 500 U/kg BW three times per week. All patients were treated as outpatients. Pre-study treatment with cyclosporin A and/or Danazol was continued in three patients. In one patient r-HuEPO was discontinued after 20 weeks because of relapse of severe aplastic anemia. No major side effects were observed even at the maximum dose. One patient with PNH showed an increase of hemoglobin from 89 to 139 g/liter that permitted monthly phlebotomies to reduce his iron overload. In one patient with MDS the reticulocyte count increased from 2.5 to 50 x 10(9)/liter, and the transfusion requirement decreased to 2 U every 3-4 weeks instead of every 2 weeks. Two patients did not complete the whole treatment period and showed no rise in reticulocyte count. We conclude that high dose r-HuEPO therapy is feasible in patients with anemia due to MDS or PNH. High-dose r-HuEPO appears to have some effect on anemia due to ineffective erythropoiesis in a subgroup of patients. Further studies are needed to identify potential responders and to define the optimal administration of r-HuEPO.

Treatment with marrow transplantation or immunosuppression of childhood acquired severe aplastic anemia: a report from the EBMT SAA Working Party

A total of 304 children under the age of 15 years with acquired severe aplastic anemia (SAA) received immunosuppressive therapy (IS) (n = 133) or a matched bone marrow transplant (BMT) (n = 171). The projected 10-year survival is 48% and 63% respectively (p = 0.002). Results following BMT have improved considerably over the years from 49% in 1970-80, to 70% in 1981-83 (p = 0.002) and to 81% between 1984-88 (p = 0.08). Other favorable prognostic factors are the use of cyclosporin A (p = 0.004), no previous therapy (p = 0.006) and early BMT (p = 0.009). In multivariate analysis only the year of treatment proved significant (p = 0.02). In contrast, results of IS are greatly dependent on the severity of pre-treatment neutropenia with survival of 56% versus 37% for neutrophils more or less than 0.2 x 10(9)/l (p = 0.003). Poor survival was associated in univariate analysis with female sex (43%), post-hepatitis SAA (37%), children not receiving androgens (38%) and patients younger than 5 years (35%), especially if associated with a low neutrophil count (11%). In multivariate analysis only the degree of neutropenia proved significant (p = 0.005). These results suggest that IS is a satisfactory alternative therapy for children with moderately SAA in the absence of an HLA-identical sibling, although BMT remains the treatment of choice. In children under 5 years with very SAA, results with IS are so poor that a search for an unrelated matched donor is justified as early as possible.

Chronic cyclosporine-associated nephrotoxicity in bone marrow transplant patients

This study describes the prevalence and degree of chronic cyclosporine-associated nephropathy and its risk factors. For this purpose we reviewed all available renal histology specimens in 169 bone marrow transplant recipients treated during an eight year period with cyclosporine for prevention of graft-versus-host-disease, and determined their pattern and degree of histomorphological changes. A total of 51 specimens obtained from 49 patients by biopsy (n = 12) or autopsy (n = 39) was evaluated. The pattern of histomorphological changes was compared with diagnosis, age, sex, and potential risk factors--such as cyclosporine dose, levels, duration of therapy, changes in serum creatinine and onset of hypertension. Morphological lesions of chronic cyclosporine-associated nephropathy were found in 67% of the specimens. They were more frequent and more severe with increasing duration of cyclosporine therapy, in patients with a higher increase in serum creatinine during the first 3 months and in patients given total-body irradiation for conditioning. These latter findings suggest that additional damage sensitizes the kidney to irreversible toxic effects of cyclosporine.

Cytotoxic and stimulatory effects of antilymphocyte globulin (ALG) on hematopoiesis

Four different preparations of antilymphocyte/antithymocyte globulin were tested in vitro for their toxicity to lymphocytes and to hematopoietic precursor cells, depending on concentration and time. Complete lymphocytotoxicity was observed at concentrations from 6.3 to 25 micrograms/ml, and suppression of colony formation by hematopoietic precursors was seen at concentrations from 12.5 to 250 micrograms/ml. Prolonged incubation time did not increase lymphocytotoxicity but augmented precursor cell damage. Lymphocytotoxicity was comparable among the four preparations tested whereas precursor cell toxicity varied widely. Antilymphocyte globulin is mitogenic and stimulates the release of hematopoietic growth factor activity by peripheral blood cells. Absorption of ALG with human T-cells eliminated precursor cell toxicity and mitogenicity but not the capacity to release hematopoietic growth factors. These results show that dose/time schedules for ALG administration may be relevant and ALG acts by virtue of inhibitory and stimulatory antibody effects.

Evaluation of the Sysmex R-1000. An automated reticulocyte analyzer

The new fully automated reticulocyte analyzer, Sysmex R-1000 (TOA Medical Electronics, Kobe, Japan), was evaluated for its routine use in the Hematological Laboratory at the University Hospital Basel, Switzerland. The operating characteristics, such as within-run precision, linearity, and carryover, fulfilled the manufacturer's specifications and are excellent. Correlation with the standard method, manual reticulocyte counting, is linear for normal and high values. For low reticulocyte counts the regression points show a deviation from their linearity. An absolute zero value is not obtained by the R-1000. The R-1000 measures total RNA content of each cell and expresses the value as low fluorescence ratio (LFR), medium fluorescence ratio (MFR), and high fluorescence ratio (HFR). The analysis of this ratio resolves the problem of zero reticulocytes: A fraction of less than 0.002 (0.2%) with an LFR of 100% represents aplasia; a shift of the intensity of fluorescence to HFR heralds regeneration. Results of samples stored at room temperature remain stable and within the range of the within-run precision for up to 12 hours, when stored at 5 degrees C for more than 48 hours. The authors conclude that the R-1000 is easy to operate, fulfills the criteria for accuracy and precision, and is highly suitable for daily routine use in a large central hematologic laboratory.

Allogeneic bone marrow transplantation (BMT) for acquired severe aplastic anaemia (SAA) in children

The SAA Registry of the EBMT now contains data on 171 children younger than 15 years of age with acquired SAA and undergoing BMT between 1970 and 1988. The overall actuarial survival is 63% at 10 years. In a multivariate Cox analysis, the year of transplant was the most important prognostic factor with a significant advantage for children grafted in 1984-88 (81%) vs 1981-83 (67%) and 1970-80 (41%) (p = 0.02). Cyclosporine A given for GVHD prophylaxis, no treatment before transplant and an interval less than 90 days from diagnosis to BMT were all favourable variables in univariate analysis. As regard to transplant procedures, the better results were obtained using Cyclophosphamide and Cyclosporine A (78%) followed by Cyclophosphamide plus irradiation plus Cyclosporine A (77%). Sex, etiology and the severity of the aplasia had no impact on survival in both uni and multivariate analysis.

Long-term follow-up of severe aplastic anaemia patients treated with antithymocyte globulin. Severe Aplastic Anaemia Working Party of the European Cooperative Group for Bone Marrow Transplantation (EBMT)

468 severe aplastic anaemia (SAA) patients registered in the EBMT-SAA registry who did not undergo bone marrow transplantation and were treated with immunosuppressive therapy (IS; 96% of patients received ATG) were evaluated. Their median age was 23 years (range 1-73) at initial IS therapy, 59% were males; in 69% the aetiology of SAA was idiopathic. Of these 468 patients, 245 had a follow-up of less than 2 years after IS 166/245 died, 71/245 are still alive, 8/245 are lost to follow-up. Of 223 patients who survived greater than or equal to 2 years (LTS long-term survivors), 191 are alive, 21 died greater than 2 years and 11 are lost. Median follow-up of 223 LTS was 4.1 years (range 2.0-10.9). Comparison of 166 patients who died less than 2 years and 223 LTS revealed no difference at time of initial IS therapy as regards sex, duration of AA, or its aetiology, but the age distribution and, in particular, severity of SAA differed significantly: more LTS were between 21 and 40 years old (44% v. 32%, P less than 0.02), less LTS had reticulocytes less than 20 x 10(9)/l (63% v. 80%, P less than 0.001), polymorphonuclear granulocytes (PMN) less than 0.2 x 10(9)/l (30% v. 57%, P less than 0.001), haemorrhages (58% v. 79%, P less than 0.002) and infection (30% v. 49%, P less than 0.005) at time of IS. A gradual improvement of blood counts was seen in patients alive greater than or equal to 2 years after IS. At 2 years after IS 80% had a normal haemoglobin and PMN greater than 0.5 x 10(9)/l, but only after 5 years 80% of cases had platelets greater than 50 x 10(9)/l. Development of clonal disease was reported of 31 LTS: 19 developed paroxysmal nocturnal haemoglobinuria (PNH), one acute leukaemia, 11 myelodysplastic syndromes and of these 11 five subsequently acute leukaemia. The majority of these patients (23/31) are still alive. Actuarial mortality of LTS is 22% at 8 years, but so far no plateau was achieved. It is concluded that SAA patients who become LTS following IS, show an improvement in haematological status but are probably not cured and are prone to develop clonal (malignant) disease.

Complete recovery of marrow function after treatment with anti-lymphocyte globulin is associated with high, whereas early failure and development of paroxysmal nocturnal haemoglobinuria are associated with low endogenous G-CSA-release

24 patients who were treated with antilymphocyte globulin (ALG) for severe aplastic anaemia (SAA) were tested for endogenous release of granulocyte colony stimulating activity (G-CSA) prior to, and at various intervals after treatment. CSA-production in vitro was induced with autologous serum as a source of 'releaser' activity, avoiding the use of plant mitogens. Before treatment, G-CSA-release was highly variable. Though mean values were higher in the 17 patients who subsequently responded to ALG treatment than in the six non-responders, this difference was not statistically significant. In the 17 responders, G-CSA-release strongly increased prior to improvement of peripheral blood counts. In one responder patient tested-before, and at regular intervals after ALG, CSA-release was high before, abnormally low at 7 d and increased again to high values before the onset of bone marrow reconstitution. In six patients who did not respond to ALG-treatment, G-CSA release decreased after treatment, and a second course of ALG was ineffective when given during this low CSA-phase. Five of the 24 patients developed paroxysmal nocturnal haemoglobinuria (PNH) at 9 months to 3 years after ALG-treatment. In all, the onset of PNH was associated with very low G-CSA-release, whether it had been high or low before treatment. We conclude that low-CSA-release after ALG treatment is a poor prognostic sign. It either indicates progression of marrow failure or heralds PNH. Such patients may be candidates for early bone marrow transplantation or treatment with G-CSF or GM-CSF.

A double-blind placebo-controlled comparison of the efficacy and safety of 50, 100, and 200 micrograms of misoprostol QID in the prevention of ibuprofen-induced gastric and duodenal mucosal lesions and symptoms

Ibuprofen, a commonly proscribed nonsteroidal anti-inflammatory drug that is also available in many countries, including the United States, without a prescription, is known to cause hemorrhage and erosion of the gastroduodenal mucosa. This study was conducted to compare the efficacy of 200, 100, and 50 micrograms of misoprostol and placebo administered qid for 6 days, with a final dose on the morning of the 7th day, in the prevention of gastric and duodenal lesions induced by the concurrent administration of 800 mg of ibuprofen qid. A total of 120 healthy subjects with endoscopically normal gastric and duodenal mucosae were enrolled in the study. The endoscopic examination was repeated 2 h after the final dose on day 7, and the mucosae were graded on a 0 to 4+ scale. In the stomach, all three misoprostol groups were significantly more protective than placebo and did not differ significantly from each other. In the duodenum, the endoscopic scores of the 200- and 100-micrograms misoprostol groups, but not the 50-micrograms group differed significantly from placebo. The 200- and 100-microgram groups did not differ significantly from each other, but both differed from the 50-micrograms group for duodenal mucosal injury. Subjective symptoms thought to be primarily attributable to the NSAID (e.g., pain, indigestion/heartburn and nausea) were recorded by each subject in a diary. Subjects in the 200-micrograms misoprostol group attained the greatest degree of mucosal protection and had a significantly higher incidence of indigestion/heartburn and abdominal pain than the placebo group. One can conclude that misoprostol in both antisecretory (200- and 100-micrograms) and non-antisecretory (50-micrograms) doses protects the gastric mucosa from injury from high anti-inflammatory doses of ibuprofen (3200 mg/day). Only the antisecretory doses (100 and 200 micrograms qid) were effective in the duodenum, suggesting that acid suppression is necessary for mucosal protection to occur in the duodenum.

Misoprostol heals gastroduodenal injury in patients with rheumatoid arthritis receiving aspirin

High-dose aspirin therapy for rheumatoid arthritis is frequently associated with severe gastrointestinal injury. To explore the possibility of reversing such damage, we conducted a double-blind, multicenter study with misoprostol, a prostaglandin E1 analog, which has demonstrated mucosal protective, gastric antisecretory, and ulcer healing properties. We also studied possible interference of misoprostol with continuing aspirin treatment in the management of patients with rheumatoid arthritis. Patients with confirmed rheumatoid arthritis and endoscopically documented gastroduodenal lesions were randomly assigned to receive 200 micrograms of misoprostol four times a day (123 patients) or placebo (116 patients). Each concurrently received 650 to 1300 mg of aspirin four times a day. After eight weeks of treatment, misoprostol was statistically superior to placebo in healing gastric mucosal injury (70% vs 25%) and duodenal mucosal injury (86% vs 53%). Patients with gastric or duodenal ulcers on admission had superior ulcer healing rates with misoprostol (67% vs 26%). There was no evidence of interference with the antirheumatic properties of aspirin. Mild to moderate adverse experiences were equally noted in misoprostol and placebo groups. Misoprostol, coadministered with aspirin, is well tolerated and highly effective in healing aspirin-associated gastroduodenal lesions in patients with rheumatoid arthritis without altering the therapeutic benefits of aspirin.

Endogenous megakaryocyte colonies from peripheral blood in precursor cell cultures of patients with myeloproliferative disorders

Megakaryocyte colony formation, as identified by conventional techniques, was observed in precursor cell cultures from peripheral blood in 8 of 20 consecutive patients with diagnosis of myeloproliferative disease (4/11 patients with polycythemia vera, 3/5 with essential thrombocythemia, 1/2 with primary osteomyelofibrosis and 2 with a myeloproliferative syndrome not further assessable), but not in 50 healthy controls (p less than 0.0001). 7 cultures showed spontaneous erythroid colonies, but were negative for megakaryocyte colonies. Megakaryocyte colony formation was independent of added erythropoietin, plasma or human leukocyte-conditioned medium, but was dependent on the presence of accessory cells. The cells in megakaryocyte colonies had the characteristic morphology of megakaryocytes and stained positively with the IIIa/IIb monoclonal anti-platelet antibody. Thus, megakaryocyte colony formation by precursor cells from peripheral blood in the absence of exogenous stimulating factors seems to be a phenomenon specific for myeloproliferative disease. Differential diagnosis of thrombocythemia may be facilitated by demonstration of endogenous megakaryocyte colony formation, which does not occur in secondary disease.

[Comparative study on in vitro lymphocytotoxicity and mitogenicity of different antilymphocyte globulin (ALG) preparations]

The lymphocytotoxicity and mitogenicity between six different ALG preparations on the clinical use world wide were compared. No significant difference in the lympholytic activity was observed between preparations and 100% cell lysis was achieved at a concentration of 50 micrograms/ml in the presence of complement. On the other hand, four preparations now in use in European countries and USA showed variable mitogenic activities on lymphocytes in the absence of complement, whereas two ALGs used in Japan did not. As the stimulatory effects of ALG on lymphocytes may contribute to the clinical outcome in the treatment of severe aplastic anemia (Kawano et al, 1988), these date can explain the poor clinical results of ALG therapy with those two preparations in Japan. Careful measures should be paid in the construction of treatment protocol and selection of ALG preparations to yield the best results.

Treatment of thrombocytosis in myeloproliferative disorders with interferon alpha-2a

In an open prospective pilot trial, we tested the effect of recombinant interferon alpha-2 a (rIFN alpha-2 a) on thrombocytosis in myeloproliferative disorders (MPD). Since October 1986, 13 patients with MPD (4 with chronic granulocytic leukemia, 4 with polycythemia vera, 3 with essential thrombocythemia and 2 with myeloid metaplasia) were treated with rIFN alpha-2 a. Platelet counts decreased in all treated patients within 2 to 10 weeks from a median value of 1,050 x 10(9)/l (range 610-1,940 x 10(9)/l) to 340 x 10(9)/l (range 230-495 x 10(9)/l). The response was dose-dependent. In 11 patients we observed a simultaneous reduction of the white blood cell count. Six patients still continue the IFN alpha-2 a therapy. In 7 treatment was discontinued, because of chronic side effects in 3, and because of noncompliance in one. In these patients, thrombocytosis recurred after discontinuation of the therapy. These results show that rIFN alpha-2 a is effective in controlling thrombocytosis in MPD. However, the long-term benefit of interferon in these disorders remains to be established.

Comparison of conventional and high-frequency ventilation in piglets after lung lavage

A piglet model of respiratory failure was used to compare airway pressures required for adequate gas exchange by a conventional positive pressure ventilator (CMV) and a high-frequency pneumatic flow interrupter (HFFI). Twelve newborn piglets (age means = 3.8 days and weight means = 1.4 kg) were given saline lung lavages after receiving intravenous Ketamine and Pavulon. Femoral and jugular vessels were catheterized for measurements of aortic and pulmonary blood pressures and gases, cardiac output, hematocrit, glucose and for the infusion of fluids. Airway pressures were measured 5 mm above the distal tip of the endothracheal tube. Lung lavage resulted in decreased static compliance and a twofold increase in pulmonary shunting. Following lavage the animals were kept on 100% oxygen and randomly assigned to either CMV (30/min) or HFFI (600/min) ventilation and thereafter were switched every 30 minutes to the alternate mode. Inspiratory duration was 33% of the total respiratory cycle during CMV and 30-50% for HFFI. Sixteen pairs of data comparing both ventilator modes were used. Blood gases, cardiovascular variables, alveolar-arterial oxygen gradient, and pulmonary shunting were not different with either ventilator. Positive end-expiratory pressure (5.3 and 5.6 cm H2O) and mean airway pressure (12.5 and 11.9 cm H2O) were equal for CMV and HFFI, respectively. Peak inspiratory pressure was significantly lower for HFFI (23.1 +/- 3.7 SD cm H2O) than for CMV (30.4 +/- 5.5 SD cm H2O). The lower peak inflation pressure required during HFFI ventilation may reduce the potential for lung rupture.

Failure of recombinant human granulocyte-macrophage colony-stimulating factor therapy in aplastic anemia patients with very severe neutropenia

Four patients with very severe aplastic anemia refractory to antilymphocyte globulin were administered recombinant human granulocyte-macrophage--colony stimulating factor (GM-CSF). One patient with minimal residual myelopoiesis responded transiently to two separate courses of GM-CSF at 4 and 8 micrograms/kg/d administered intravenously and another course at 4 micrograms/kg/d administered subcutaneously. Septicemia and bilateral pneumonia that had been resistant to conventional therapy resolved. Three patients with no evidence of residual myelopoiesis did not respond to GM-CSF. In one patient, the dose was increased to 32 micrograms/kg/d with no effect on hematopoiesis. Immediate side effects were minimal at GM-CSF doses up to 16 micrograms/kg/d. GM-CSF may, however, have been involved in the pathophysiology of thrombosis of the inferior vena cava in the patient administered 32 micrograms/kg/d. We conclude that GM-CSF does not induce hematopoiesis in long-standing, severe, treatment-resistant aplastic anemia with complete myelopoietic failure. However, in patients with minimal residual myelopoiesis, GM-CSF could be a promising adjuvant therapy for severe infection.

Irradiated donor buffy coat following T cell-depleted bone marrow transplants

Twenty patients aged 27-47 years (median, 35 years) with hematological malignancies, treated with T cell-depleted bone marrow transplantation received in a pilot study five donations of 15 Gy irradiated donor buffy coat cells at days +1, +3, +5, +7, +14 in order to prevent rejection and leukemic relapse. Patients were conditioned with etoposide, cyclophosphamide and 12 Gy fractionated total body irradiation and given cyclosporine postgrafting. Donor bone marrow was T cell-depleted (median 3% remaining T cells) by counterflow elutriation. All patients engrafted. Fourteen (70%) are alive. Two are living with relapse, 12 (60%) are alive and well without any signs of disease, 2-27 months (median, 9 months) post-transplant. Three patients died of interstitial pneumonitis and/or graft-versus-host-disease; three died of relapse. This pilot study supports previous animal data. Repeated infusions of 15 Gy irradiated donor buffy coat are feasible and do not appear to increase transplant related mortality. Whether this approach ultimately will reduce the rate of rejection and relapse following T cell depletion needs to be confirmed in a larger, prospective study.

[Late complications in patients with aplastic anemia]

Of 145 patients with severe aplastic anemia (SAA) treated in Basel from 1976 to 1987, 34 underwent bone marrow transplantation (BMT) and 111 received ALG therapy. We have analyzed the incidence of late complications in both groups of patients. 34 patients treated with ALG developed a hematological complication, 10 a myelodysplastic syndrome (MDS) and 18 paroxysmal nocturnal hemoglobinuria (PNH) associated with clinical symptoms in 12. Two patients had both MDS and PNH. Eight suffered relapse of SAA. After BMT neither of these complications occurred. Most of the non-hematological problems were associated with therapy. In the ALG group androgens were responsible for impotence and gynecomastia in men, deep voice in women and liver tumors in 4 patients. Four other patients developed aseptic necrosis of the hip and one carcinoma of the breast. The most severe late complication after BMT was chronic graft-versus-host disease (GvHD), occurring in patients still receiving methotrexate for prophylaxis of GvHD.

Bone marrow transplantation (BMT) versus immunosuppression for the treatment of severe aplastic anaemia (SAA): a report of the EBMT SAA working party

This is an analysis of 509 patients with severe aplastic anaemia (SAA) treated in Europe between 1981 and 1986; 218 patients were treated by allogeneic bone marrow transplantation (BMT) from HLA identical sibling donors and 291 with immunosuppressive therapy (IS) with antilymphocyte globulin (ALG). The overall actuarial survival was 63% after BMT and 61% after IS therapy at 6 years. All patients fulfilled the criteria of SAA; however, most patients with a neutrophil count of less than 0.2 x 10(9)/l also had infections and haemorrhages. Therefore a further subclassification was defined by pretreatment peripheral blood neutrophil count: very severe aplastic anaemia (vSAA) (less than 0.2 x 10(9)/l neutrophils) and moderately severe aplastic anaemia (mSAA) (0.2-0.5 x 10(9)/l neutrophils). A Cox regression analysis showed that the only significant pre-treatment variables were a low neutrophil count (P = 0.001) and increasing age (P = 0.05). Thus it seemed reasonable to analyse survival data after combined stratification for neutrophils (vSAA versus mSAA) and age (cut off at 20 years). BMT was superior to IS in patients with vSAA under 20 years of age (64% v. 38%; P = 0.01). IS was superior to BMT in patients with mSAA aged 20 or more (82% v. 62%; P = 0.002). The two treatments gave comparable results in young patients with mSAA (BMT = 58%, IS = 62%; P = 0.1), and in older patients with vSAA (BMT = 44%, IS = 43%; P = 0.06). Overall 75/218 and 87/291 patients, given BMT or IS respectively, died. The major cause of failure in BMT patients was graft rejection (n = 22) or problems associated with graft-versus-host disease. For ALG patients the major problem was persistence of the aplasia with haemorrhage (n = 32) or infections (n = 46). This study indicates that over 60% of patients with SAA can be successfully treated with either BMT or IS. Overall survival does not differ in the two groups, though significant differences emerge after stratification for severity of the aplasia and age.

Late haematological complications in severe aplastic anaemia

137 patients with severe aplastic anaemia (SAA) were treated in Basel from 1976 to 1986. 34 underwent bone marrow transplantation (BMT) and 103 received antilymphocyte globulin (ALG) therapy. We have analysed the incidence of late haematological complications in both groups of patients. 20 patients treated with ALG developed a late haematological complication. A myelodysplastic syndrome or frank leukaemia occurred in eight and paroxysmal nocturnal haemoglobinuria (PNH) in 13 patients. Nine of the 13 patients with PNH had clinical signs of haemolysis, four only had positive laboratory tests. One patient had PNH and acute leukaemia. The risk of developing a haematological complication increased continuously and reached 57% at 8 years. Neither PNH nor leukaemia occurred in patients treated with BMT. The increased survival rate and the long observation time after ALG therapy have revealed a new perspective of the prognosis of aplastic anaemia. Patients treated with BMT appear to be cured whereas those treated with ALG remain at risk for late complications.

Testosterone reduces complement sensitivity of precursor cells in aplastic anaemia patients treated with antilymphocyte globulin

Of 53 consecutive patients with aplastic anaemia who were re-examined at various intervals after treatment with antilymphocyte globulin, 30 had sufficient bone marrow colony forming capacity to permit evaluation of androgen effects in vitro. In 22 patients, precursor cells of the myeloid and erythroid line were abnormally sensitive to a preincubation in isosmolar sucrose with 5% fresh autologous serum compared to heat-inactivated autologous serum. This phenomenon was interpreted as excess complement sensitivity. This inhibitory effect of fresh serum in the bone marrow sucrose test was abrogated by addition of 10(-6) M testosterone to the preincubation phase in 15 of the 22 patients. In six of these 15, 10(-7) M dexamethasone had a similar effect; in the other nine patients only testosterone rendered the bone marrow sucrose test negative. This effect of testosterone on colony growth was indirect, since addition of 10(-9)-10(-5) M testosterone to primary bone marrow cultures from the same patients had no effect. We propose that testosterone in these experiments interacted with the complement system. In patients who have complement sensitive precursor cells, androgens might thus prevent complement mediated lysis of haemopoietic cells to some extent. The test described could help identification of patients in autologous bone marrow remission who are likely to benefit from androgen treatment.

Repair of UV-induced DNA damage in aplastic anaemia: changes after treatment with antilymphocyte globulin (ALG)

The extent of DNA-repair induced by UV-C irradiation was measured in peripheral unstimulated lymphocytes of 24 patients with aplastic anaemia at different stages of disease and compared with the results obtained in 92 controls. As parameter of the DNA-repair synthesis, the incorporation of (3H)thymidine in the presence of 2 mmol/l hydroxyurea (HU) was taken. Of 19 patients tested after treatment with antilymphocyte globulin (ALG), 5 were in complete autologous haemopoietic remission, defined as greater than 1000 granulocytes/mm3, greater than 100,000 platelets/mm3 and a nontransfused haemoglobin value greater than 10 g%. 14 patients were in partial remission, defined as improvement of haemopoietic function, not meeting the criteria for complete remission. 4/5 patients in complete remission had normal DNA-repair synthesis, compared to 4/14 patients in partial remission. In 92 controls, a normal level was found in 70 cases. In 4/5 patients examined at diagnosis and at various intervals after ALG-treatment, DNA-repair synthesis was low at diagnosis. It increased after therapy and paralleled improvement of haemopoietic function to some extent. It is suggested that in aplastic anaemia there are different populations of lymphocytes with differing DNA-repair capacity; ALG treatment seems to favour expansion of the normal population, which is associated with improvement of haemopoietic function.

Abundant macrophage growth in culture from patients with chronic myelogenous leukemia: a risk factor for graft-versus-host disease after bone marrow transplantation

Peripheral blood cultures of hemopoietic precursor cells from 30 patients with chronic myelogenous leukemia showed different growth patterns before bone marrow transplantation. A strong increase of free and clustered macrophages was seen in 11/30. Of these 11 patients, 10 developed Graft-versus-Host Disease (GvHD). Of 19 patients without the macrophage pattern, 4 developed GvHD (p = 0.004). Of 14 patients with GvHD, 10 had shown the macrophage pattern before bone marrow transplantation, compared to 1/19 without GvHD (p = 0.004). We postulate that excess macrophages in the bone marrow recipient trigger GvHD by enhancing presentation of recipient antigens to donor T-lymphocytes, and that their presence is predictive of GvHD in CML.

Secondary leukemia after severe aplastic anemia

We describe a patient with acute myeloid leukemia (AML) occurring 5 years after successful treatment of severe aplastic anemia (SAA) with antilymphocyte globulin (ALG). Four years after ALG, SAA had relapsed. A second remission of SAA was achieved, but was followed by transformation of the myelodysplastic syndrome into overt AML. After 2 courses of high-dose cytosine arabinoside and VP-16 complete remission occurred. This case shows that chemotherapy of secondary leukemia after SAA is feasible, and that ex-aplastic bone marrow is capable of complete recovery from chemotherapy-induced aplasia. Morphological anomalies of bone marrow noticed early during remission of SAA might predict a late transformation in leukemia.

Necrotizing tracheobronchitis following high-frequency ventilation: effect of lung deflation

A piglet model of acute respiratory failure was used to determine whether necrotizing tracheobronchitis (NTB) reported during high-frequency pneumatic flow interrupter (HFFI) ventilation could be minimized by a different ventilatory strategy. Twenty-one piglets (mean age 3.8 days, average weight 1.4 kg) were anesthetized with ketamine and given Pavulon prior to saline lung lavage. Femoral vessels were cannulated for measurements of blood pressures, arterial blood gases (ABG), and fluid administration. Airway pressures were measured 5 mm above the endotracheal tube tip. To allow for lung deflation, HFFI (10 Hz) was programmed to pause for 1 sec either 5 (HFFI5) or 12 times per min (HFFI12). Seven animals were assigned to each of the treatment groups and to a conventional mechanical ventilation (CMV) control. All animals were kept on 1.0 FIO2 with ventilators adjusted to maintain ABG (pO2 = 50-100 mmHg and pCO2 = 30-40 mmHg). After 6 h of ventilation, the animals were sacrificed and their lungs inflated with formalin to 40 cm H2O. Sections were obtained from trachea, carina, mainstem, and hilar bronchi. An airway injury score (AIS) was calculated after "blinded" microscopic evaluation. There was no difference in total AIS between CMV (2.4) and HFFI12 (8.6) but a statistically significant difference (p less than 0.05) existed between CMV and HFFI5 (14.1). NTB was limited to the trachea during HFFI12 but extended down to the hilar bronchi during HFFI5. More frequent lung deflations reduce the severity and distribution of NTB during HFFI ventilation.

Immunostimulatory effects of different antilymphocyte globulin preparations: a possible clue to their clinical effect

Antilymphocyte globulin (ALG) and antithymocyte globulin (ATG) have an established role in the treatment of severe aplastic anaemia. The response rate ranges from 40% to 80%. Its mode of action is believed to be complement dependent lysis of immunocompetent cells which inhibit haemopoietic maturation. This might not be the sole mechanism. We have tested four different preparations of ALG/ATG for their mitogenic effect on normal peripheral blood cells and on enriched T-cells in vitro by 3H-thymidine incorporation. We found marked differences between the four preparations. One was strongly mitogenic and able to induce profound release of haemopoietic growth factors. This mitogenic effect could be detected in the serum of patients during ALG treatment. Clinical response rates of this preparation are about 80%. Three other preparations were of lower or no stimulatory effect. Clinical response rates with these preparations vary between 40% and 60%. From our results, we postulate that the beneficial effect of ALG could be partially due to its ability to stimulate release of haemopoietic growth factors. The mitogenicity of different ALG/ATG preparations should be tested as an in vitro parameter of clinical efficacy.