Allogeneic BMT Recipients Research Articles

Thrombotic microangiopathy in blood and marrow transplant patients receiving tacrolimus or cyclosporine A.

Cyclosporine A (CSA) and tacrolimus (FK-506) are both associated with thrombotic microangiopathy (TMA) in allogeneic BMT recipients, although it is not known which drug is more likely to cause the syndrome. The optimal treatment of BMT-associated TMA is also not known. To estimate the risks, predisposing factors, and outcomes of TMA, data were analyzed from two cohorts of BMT patients who had received CSA or FK-506 in our institution with the same clinical definition for TMA. TMA was diagnosed in 11 of 55 patients (CSA, 3 of 24; FK-506, 8 of 31). The daily risk of developing TMA was 0.12 percent for patients receiving CSA and 0.26 percent for those receiving FK-506 (p = 0.16, chi-square). Among patients receiving FK-506, sibling donor BMT recipients were as likely to develop TMA as matched unrelated donor recipients. Serum CSA and FK-506 concentrations were not elevated above the therapeutic range in most patients with TMA. The blood urea nitrogen to serum creatinine ratio was elevated in patients with TMA. Despite daily plasmapheresis, 9 of 11 patients died without resolution of TMA; however, the causes of death were multifactorial, including GVHD. Histologic evidence for TMA was absent in 1 patient who died with persistent clinical signs attributed to microangiopathy. In this study, a high incidence of TMA was found in patients receiving either CSA or FK-506 following BMT, with uniform diagnostic criteria and strict monitoring. Neither drug showed elevated levels in most patients with TMA. Plasmapheresis was unsuccessful in reversing most cases of TMA.

Reimmunization after bone marrow transplantation: Current recommendations and perspectives

Autologous and allogeneic BMT recipients lose immune memory of exposition to infectious agents and vaccines accumulated throughout lifetime and therefore need to be revaccinated. Diphtheria toxoid, tetanus toxoid, pertussis vaccine (children < 7 years old), Haemophilus influenza type B (Hib) conjugate, 23-valent pneumococcal polysaccharide, inactivated influenza vaccine, inactivated polio vaccine and live-attenuated measles-mumps-rubella vaccine are the currently recommended vaccines to be included in a vaccination program after BMT. For most of them, the best time of vaccination, the number of vaccine doses and/or the duration of immunity after vaccination have not been established. Vaccination protocols vary greatly among BMT centers suggesting that the lack of sufficient data has not permitted the establishment of solid recommendations. The use of other vaccines and the perspectives for different vaccination protocols are discussed in this review.

Extended antigenemia surveillance and late cytomegalovirus infection after allogeneic BMT.

Late CMV disease remains a major concern in allogeneic BMT recipients. Few surveillance data are available on the occurrence of CMV infection and recurrences after day +100. We evaluated the occurrence of antigenemia (AG) recurrences until day +365 in 76 patients who received pre-emptive ganciclovir (GCV) therapy prompted by AG > or = 2 positive cells. Sixty-two episodes of AG recurrences were detected in 33 of the 52 patients who had positive AG. Survival analysis showed a 45.4% probability of AG recurrence on day +100, 64.8% on day +180 and 71.2% on day +365. The median time for AG recurrences was 113 (35 to 343) days. Thirty-five of the 62 episodes (56.4%) occurred after day +100. More than 70% of the patients responded to a 2-week course of GCV and no CMV disease was observed shortly after discontinuation of GCV. The Cox proportional model showed a significant effect of AG recurrences on patient's follow-up only when the patient developed chronic GVHD (P = 0.012). Extended surveillance favored early introduction of GCV and late CMV pneumonia occurred in only one of the 76 patients (1.3%). AG recurrences are frequent after day +100 and extended surveillance until day +365 is recommended for patients who develop chronic GvHD.

Gastroparesis following bone marrow transplantation.

Patients often develop nausea, vomiting and bloating after bone marrow transplantation (BMT). These symptoms may interfere with nutrition and the ability to take oral medications. Gastroparesis is a recognized cause of these symptoms in non-transplant patients but less is known about patients who undergo BMT. Between January 1996 and March 1997, a total of 151 patients underwent BMT. Eighteen patients (12%) developed persistent symptoms suggestive of gastroparesis (persistent nausea, vomiting or bloating). Scintigraphic gastric emptying studies were performed to assess for gastroparesis. Prokinetic agents were administered at the time of study. The records on these patients were compared with those of all other patients undergoing BMT during the same time period without these symptoms. Nine patients who demonstrated delayed gastric emptying were further evaluated with esophagastroduodenoscopy and biopsy. Biopsy samples were reviewed for evidence of graft-versus-host disease (GVHD). Fourteen of 18 patients demonstrated delayed gastric emptying and most responded to prokinetic agents given at the time of study. Age, conditioning regimen, cytomegalovirus antigenemia and acute GVHD did not appear to be associated with the development of gastroparesis. Allogeneic BMT recipients were at higher risk than autologous BMT patients (26% vs 0%, P < 0.0001). of allogeneic bmt recipients, there was a nonsignificant trend of patients receiving tacrolimus to be less likely to experience gastroparesis than those receiving cyclosporine (27% vs 48%, P = 0.08). For the nine patients undergoing upper endoscopy, GVHD on gastric biopsy was an uncommon finding and was mild when present. Gastroparesis appears to be a common cause of nausea, vomiting and bloating following allogeneic BMT. This may occur less often with tacrolimus than cyclosporine because of the former agent's prokinetic properties. Patients usually respond to prokinetic drugs at the time of scintigraphy. GVHD and CMV infection do not appear to be major contributing factors.

Longitudinal study of bacterial, viral, and fungal infections in adult recipients of bone marrow transplants.

The epidemiology of infections was studied in a retrospective cohort of 446 recipients of bone marrow transplants (BMTs; 92 of which were allogeneic and 354 of which were autologous) during 1993--1996. Infections that were microbiologically documented in 274 recipients included bacteremia, urinary tract infections, cytomegalovirus viremia, fungemia, invasive aspergillosis, and catheter-related infections. During the period of neutropenia, no differences were found between recipients of allogeneic BMTs and recipients of autologous BMTs with regard to the incidence and the nature of infection. After patients underwent engraftment, bacteremia, cytomegalovirus viremia, and invasive aspergillosis were significantly more common in recipients of allogeneic BMTs than in recipients of autologous BMTs. Deaths caused by infection were uncommon and were mainly the result of invasive aspergillosis. Therefore, empirical antimicrobial therapy should be the same for recipients of both allogeneic and autologous BMTs during the period of neutropenia; after engraftment, more attention should be paid to the risk of infection in allogeneic BMT recipients, particularly with regard to detection and prevention of invasive aspergillosis.

Cytomegalovirus pneumonia in adult autologous blood and marrow transplant recipients.

CMV pneumonia is a major cause of morbidity and mortality among allogeneic BMT recipients. To assess the frequency, timing, risk factors and response to therapy of CMV pneumonia among autologous BMT recipients, we reviewed our experience with 795 patients. Sixteen (2%) patients were diagnosed with CMV pneumonia. The frequency was higher among patients who were seropositive than those who were seronegative (3.3% vs 0%, P = 0.008). Among seropositive patients, the frequency was higher among patients with hematological malignancies than patients with solid tumors (5.0 % vs 1.0%, P = 0.019). Eleven cases occurred <30 days, and five cases occurred >100 days post transplant. The overall CMV pneumonia-related mortality rate was 31%. Seven (78%) of nine patients treated with ganciclovir and IVIG prior to respiratory failure survived; neither of two patients treated after respiratory failure survived. Four of five (80%) untreated patients survived. In conclusion, CMV is a not infrequent cause of pneumonia among autologous BMT recipients. Risk factors include CMV seropositivity and an underlying hematological malignancy. A favorable response hinges on the prompt initiation of therapy. The survival of 25% of the patients without antiviral therapy suggests that the isolation of CMV from a BAL specimen occasionally reflects oropharyngeal contamination or that CMV pneumonia may sometimes be self-limited in more immunocompetent autologous BMT recipients.

Loss of renal function following bone marrow transplantation: an analysis of angiotensin converting enzyme D/I polymorphism and other clinical risk factors

Chronic renal failure is an acknowledged late complication of BMT. It is related to the intensive chemotherapy, radiation and supporting medications. Polymorphism in the angiotensin converting enzyme (ACE) gene is associated with progression of nephropathy caused by diabetes and IgA nephropathy. We sought to determine whether ACE genotype and other clinical factors were associated with loss of renal function after BMT. We determined the genotype of 106 adult allogeneic BMT recipients, who received a similar preparative regimen, survived 1 year, and had assessment of renal function up to 3 years after BMT. We found that the distribution of genotypes was similar to the general population; 29%, 51%, and 20% for the DD, DI, and II genotypes, respectively. There was no statistical difference in patient survival between the three groups. Among all patients, the average creatinine clearance declined from 124 (95% CI 117, 131) to 89 (95% CI 78, 100) ml/min over the 36 months after BMT. Decline in renal function over time was less for patients with the DD compared to the II genotype (P = 0.040). Renal function in patients with the DD genotype was also better than those with the DI genotype, but this was of borderline statistical significance (P = 0.055). Renal shielding reduced decline in renal function compared to no shielding (P = 0.026). We conclude that the ACE genotype does not seem to influence survival, but the DD genotype may be protective against renal injury after BMT. Furthermore, we confirm that renal shielding during TBI reduces the renal injury after BMT.

Opsonophagocytic activity against Streptococcus pneumoniae type 19F in allogeneic BMT recipients before and after vaccination with pneumococcal polysaccharide vaccine

Opsonophagocytic activity (OPA) of pneumococcal polysaccharide (Pnc PS) antibodies in vitro, a measure of antibody functional activity, usually correlates with specific IgG antibody concentrations measured by an EIA method. In order to investigate the functional activity of specific Pnc PS antibodies, we determined IgG antibodies to Pnc PS type 19F by an EIA method and OPA against Pnc type 19F by a killing assay in a randomized study, where 23 adult allogeneic BMT recipients were vaccinated with Pnc PS vaccine at 8 months (early group) and 21 recipients at 20 months (late group) after transplantation. Serum samples drawn before BMT, before vaccination, and at 1 and 16 months after vaccination were available from 27, 35, 34 and 30 patients, respectively. The geometric mean anti-Pnc 19F concentrations were 4.3, 1.3, 1.6 and 1.3 microg/ml in the early group and 3.8, 0.9, 0.6 and 0.6 microg/ml in the late group before transplantation, before vaccination, and at 1 and 16 months after vaccination, respectively. OPA (titre > or = 8) was found in 10/27, 5/35, 5/34 and 6/30 patients before BMT, before vaccination, and at 1 and 16 months after vaccination, respectively. The specific IgG antibody concentration and OPA correlated with each other before BMT, and in the early group patients before and at 1 month after vaccination. The results demonstrate that after Pnc PS vaccination allogeneic BMT recipients have antibodies with low functional activity to a Pnc PS antigen associated with low specific IgG responses. There is a need to study new Pnc conjugate vaccines in multi-dose schedules for their capacity to elicit higher specific antibody concentrations with high OPA in BMT recipients.

Treatment and outcome of invasive Aspergillus infections in allogeneic BMT recipients.

The outcome of invasive aspergillosis (IA) has been considered poor in allogeneic BMT recipients. We analyzed retrospectively the treatment and outcome of IA diagnosed during life in a recent cohort of 20 allogeneic BMT recipients. All patients were initially treated with amphotericin B (AmB) (conventional 16, liposomal 4). Due to toxicity, conventional AmB was changed to a liposomal preparation in 10 patients. Five patients also received itraconazole and three underwent surgery. Of 19 evaluable patients, two patients achieved a complete response and a partial response was observed in five patients (response rate 37%). The median survival was 37 days after the diagnosis. Only two patients (10%) were cured. The prognosis of allogeneic BMT recipients with IA has remained poor. Although treatment responses are common, immunosuppression aggravated by GVHD and its treatment, as well as the commonly disseminated presentation of IA, seem to be major obstacles to the success of therapy. Bone Marrow Transplantation (2000) 26, 759-762.

Liver disease during the first post-transplant year in bone marrow transplantation recipients: retrospective study

Liver dysfunction is a common problem in BMT recipients and it is important to determine the etiology in order to institute appropriate therapy. The purpose of this study was to evaluate the possible causes of liver dysfunction during the first post-transplant year in BMT recipients and to identify a possible relationship between pre-existing liver dysfunction and viral hepatitis with prognosis after BMT. We reviewed liver status before and after BMT in 130 consecutive patients at the Catholic Hematopoietic Stem Cell Transplantation Center. Liver dysfunction during the first post-transplant year occurred in 85 out of 101 (84. 2%) allogeneic BMT recipients and 13 out of 29 (44.8%) autologous BMT recipients. In allogeneic BMT, GVHD and drug hepatotoxicity were major causes. In autologous BMT, drug hepatotoxicity was the most common cause. Eighteen out of 130 patients (13.8%) had abnormal liver function tests before BMT. These patients did not have an increased risk of post-transplant liver dysfunction, GVHD, and death compared to patients who had normal liver function tests prior to BMT. Nine patients were hepatitis B antigen positive and three patients were anti-HCV positive prior to BMT. There was no significant increase in the incidence of post-transplant liver dysfunction, GVHD, and death in these patients.

Diagnostic aspects of invasive Aspergillus infections in allogeneic BMT recipients.

To investigate diagnostic aspects of invasive aspergillosis (IA) in allogeneic BMT recipients, the charts of 22 consecutive patients with IA transplanted in 1989-1995 were reviewed. IA was diagnosed 69-466 days (median 131 days) post BMT. In 16 patients (73%), a definite or probable diagnosis of IA was made during life. Respiratory symptoms were the presenting feature in half of the patients followed by neurological symptoms (27%). Chest X-ray revealed single or multiple nodular lesions in 10 patients; cavitation was observed in five patients. Tissue biopsy was the most common method of diagnosis (nine patients: lungs 6, liver 1, subcutaneous tissue 1, brain 1). Five IA cases were detected by nine guided fine needle lung biopsies in eight patients and without complications. Bronchoalveolar lavage was performed in 14 patients with findings suggestive of invasive pulmonary aspergillosis in eight cases. Lungs were the most common organ affected (90%) followed by central nervous system (41%). The diagnosis of IA is still difficult, and a large number of patients have advanced infection at diagnosis. Methods for early diagnosis are needed. Patients with a clinical suspicion of IA should be treated vigorously with antifungal agents during the diagnostic work-up.

Cytomegalovirus disease in adult marrow transplant recipients receiving ganciclovir prophylaxis: a retrospective study.

In a retrospective study, we compared the incidence and risk of mortality associated with CMV disease in adult allogeneic BMT and PBSC recipients who received ganciclovir prophylaxis three-times-per-week (78 patients) vs five-times-per-week (137 patients). Active CMV infection occurred in 28 (41%) and 26 (21%) in the three- vs five-times-per-week groups, respectively (P < 0.005). CMV disease developed in 11 (16%) and five (4%) patients who received ganciclovir prophylaxis in the three-times-per-week vs five-times-per-week groups (P < 0.004). The CMV-attributable mortality rate was 1.5% and 12% in the five- vsthree-times-per-week groups, respectively (P < 0.003). Risk factors for CMV disease, significant at the P < 0.05 level in the multivariate analysis, were ganciclovir prophylaxis at three-times-per-week, receiving a T cell-depleted (TCD) marrow, and tacrolimus as prophylaxis for GVHD. These data suggest that ganciclovir five-times-per-week significantly reduced the incidence and mortality of CMV disease in allogeneic BMT and PBSC recipients. However, ganciclovir five-times-per-week was less effective for the prevention of CMV disease in patients receiving TCD marrow or tacrolimus.

Human herpes virus 8 (HHV8) serology in allogeneic bone marrow transplant recipients.

Human herpes virus 8 (HHV8) may be sexually transmitted, but transmission via blood cells has not yet been excluded. We used a modified immunofluorescence assay to detect Ab to HHV8 latency-associated nuclear Ag in sera of 200 allogeneic BMT recipients and their related donors. In control subjects, Ab were found in 85% of patients with AIDS-related Kaposi sarcoma (n = 52), 34% of HIV-1 infected subjects without Kaposi sarcoma (n = 56) and 9. 5% of blood donors (n = 42). Among BMT donors, 14.5% were HHV8+, while 10% of recipients were positive before, and 18% after BMT. In the 176 HHV8-negative recipients at BMT, there was no relationship between post-BMT seroconversion, which occurred in 26 cases (15%), and the donor's serological status. Of note, 10 HHV8+ recipients before BMT became negative post-BMT. Outcome of BMT was not influenced by prior HHV8 seropositivity, seroconversion or seroreversion of recipients. That HHV8 seropositivity among blood donors from the Paris area was comparable to that of BMT donors and recipients before BMT indicates that these patients had not been at risk of HHV8 by blood products received before BMT, although post-BMT HHV8 seroconversion probably corresponded to contamination by blood transfusions rather than by the BMT.

The effect of T cell depletion with Campath-1M on immune reconstitution after chemotherapy and allogeneic bone marrow transplant as treatment for leukaemia.

The prophylactic use of T cell depletion (TCD) strategies for the prevention of graft-versus-host disease (GVHD) following allogeneic stem cell transplantation remains widespread. Initial reports of high incidence of graft rejection after TCD BMT led to a move away from this approach but improved conditioning regimens have reduced this risk substantially. The use of TCD has also been associated with higher relapse risk post-BMT although the success of donor leukocyte infusion (DLI) as treatment for relapse has reduced this problem, especially in chronic myeloid leukaemia (CML). Currently the use of TCD BMT is increasing particularly due to the relative increase in BMT from non-related donors for whom TCD is the optimal GVHD prophylaxis. However, doubts remain over the long-term effect on the reconstituted immune system of recipients of TCD BMT, particularly in adult recipients. In this study we have undertaken a detailed sequential analysis in 23 patients who received allo-grafts from HLA-identical sibling donors after high-dose chemo/radiotherapy for acute or chronic leukaemia. Of these patients, 11 received non-manipulated grafts, five received 'partially TCD' (PTCD) and a further seven received 'fully TCD' (FTCD) bone marrow. T cell depletion was performed ex vivo by Campath-1M plus autologous serum as a source of complement. Partial TCD describes grafts with a T cell reduction of 1-2 log. Full TCD refers to grafts with a reduction of >2.5 log. The decision regarding the optimal degree of TCD was clinical and was based upon the perceived relative risk of relapse based upon the disease and remission status. All patients were monitored for up to 12 months post-BMT with regard to reconstitution of T and NK cell subsets. T cell depletion at either level was associated with a slower recovery of CD4 cells. This was most marked in the FTCD recipients and lasted throughout the period of study. CD8 cell recovery was also slower in the TCD recipients but this normalised throughout the 12 months post-BMT. The ratio of CD45RA+:CD45RO+ increased in all recipients after month 3. This suggests that a degree of extra-thymic T cell maturation can occur in recipients of allogeneic BMT. NK cell recovery was more rapid in the TCD recipients and these differences were maintained throughout the first year.

Incidence and risk factors for invasive fungal infections in allogeneic BMT recipients.

In order to analyze the incidence and risk factors for invasive fungal infection (IFI) after allogeneic BMT, 142 consecutive adult BMT recipients (131 sibling donors, 11 unrelated donors) transplanted in 1989-1993 were retrospectively analyzed. There were 21 cases with definite or probable IFI (incidence 15%) (Aspergillus, 15; Candida, four; Fusarium, one; Absidia, one). The median time to the diagnosis of IFI was 136 days after BMT (range 6-466 days). Only 14% of the IFIs were found during the neutropenic period post-BMT. Of the pretransplant characteristics, hematological disease (MDS vs other) (P = 0.001) and unrelated donor (P = 0.01) were risk factors for IFI. Acute GVHD grade III-IV (P = 0.03) and extensive chronic GVHD (P = 0.0002) were also found to be significant risk factors. Only three patients with IFI (14%) became long-term survivors. Invasive fungal infections tended to develop late after BMT, were usually caused by Aspergillus sp., and were strongly associated with GVHD and its treatment. Better prophylaxis and treatment of IFI are needed. More effective prophylaxis for GVHD might decrease the risk of IFI after allogeneic BMT.

Prevention of CMV Disease in Allogeneic BMT Recipients by Cytomegalovirus Antigenemia-Guided Preemptive Ganciclovir Therapy

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Prevention of CMV disease in allogeneic BMT recipients by cytomegalovirus antigenemia-guided preemptive ganciclovir therapy.

Cytomegalovirus (CMV) infection can cause severe disease and mortality in recipients of allogeneic bone marrow transplants (alloBMT) when either the donor or recipient is CMV seropositive (high-risk alloBMT). We investigated the efficacy of preemptive therapy guided by detection of CMV antigenemia. In 11 high-risk alloBMT recipients, high-dose ganciclovir (GCV) treatment was initiated at first positive antigenemia and was continued until antigenemia became negative. The treatment strategy prevented CMV disease during the follow-up period of the study in 7 alloBMT recipients with positive CMV antigenemia. Three other patients who were shown to be CMV antigenemia negative but positive for CMV DNA in blood by the polymerase chain reaction (PCR) were not treated and did not develop CMV disease. The eleventh patient was negative for CMV by all tests for the duration of the study and did not develop CMV disease. We have found antigenemia-guided preemptive GCV therapy to be an effective strategy for the prevention of CMV disease in high-risk alloBMT recipients.

Hemorrhagic cystitis after bone marrow transplantation. Risk factors and complications.

Hemorrhagic cystitis (HC) is a major cause of morbidity after BMT; we have analyzed its incidence, risk factors, and complications in 977 patients undergoing BMT between 1974 and 1988. Despite vigorous hydration and frequent voiding in all patients receiving cyclophosphamide, 135/977 (15% by Kaplan-Meier projection) developed HC (micro- or gross hematuria, dysuria, bladder pain) between -11 and +100 days (median +22) after BMT. Of these, 60 had severe HC, including major urinary obstruction (4/60), renal failure (13/60), or need for surgical or chemical bladder cauterization (16/60). By univariate analysis, allogeneic BMT recipients had more frequent HC than autologous patients (17% vs. 9%, P = 0.002). In addition, allogeneic patients with adenoviruria were at increased risk for the development of HC. Patients with aplastic anemia conditioned with high dose cyclophosphamide and total lymphoid irradiation had the highest rate of HC (22%) versus those with hematologic malignancies (15%, P = 0.03). A Cox proportional hazards regression model was used to further identify those factors independently associated with HC. In all regression models, the factor most highly associated with the development of HC was the finding of adenovirus in the urine preceding the onset of hematuria. HC-related morbidity, and its associated increased hospitalization costs, frequently complicates BMT. Improved prophylactic measures, perhaps including the use of 2-mercaptoethane sulfonate, are needed, at least for allogeneic BMT patients with their attendant risk of adenovirus infection.

Viral infections in leukemia and bone marrow transplant patients.

Infections by herpesviruses are common phenomena in patients being treated for acute leukemia and those undergoing bone marrow transplantation. Reactivation of endogenous latent virus caused by the immunosuppressive and cytotoxic effects of cytoreductive therapies is a common mechanism of infection. With cytomegalovirus (CMV), acquisition of exogenous virus by transfusion of blood products containing virus and from the bone marrow graft in the case of bone marrow transplantation can occur. Serious morbidity can result and occasional mortality. CMV infections in allogeneic BMT recipients have high case fatality rates. Treatment and preventive strategies for herpes simplex virus (HSV), CMV, and varicella zoster virus (VZV) have been developed to reduce morbidity. Acyclovir, either given prophylactically or as treatment of active infection, has been highly successful in reducing illness from HSV and VZV infection. For CMV, provision of CMV-seronegative blood products is the mainstay of prevention of morbidity in seronegative patients and is especially important in the care of patients undergoing allogeneic BMT. Ganciclovir given either prophylactically or as early therapy for patients detected to be shedding CMV appears to be a promising strategy. Bolstering host immunity through augmentation of anti-CMV cytotoxic T-cell responses appears to be an exciting candidate therapy under development.

Circulating erythropoietin levels after bone marrow transplantation: inappropriate response to anemia in allogeneic transplants

We studied 24 recipients of autologous bone marrow transplantation (ABMT) or allogeneic BMT (BMT) to determine whether impaired erythropoietin (Epo) response to anemia could delay full erythropoietic recovery. Observed Epo levels were compared with predicted levels based on the relationship between Epo and hematocrit in 125 control subjects. Circulating Epo levels were normal during conditioning and the early posttransplant period. Between days 21 and 180, Epo levels remained normal in ABMT patients but were inappropriately low for the degree of anemia in BMT patients. Median time to full erythropoietic engraftment was longer in BMT than in ABMT recipients. Circulating Epo returned to appropriate levels after day 180, except in patients with active cytomegalovirus infection. We conclude that impaired Epo response to anemia can contribute to delayed erythropoietic recovery after allogenic BMT. Renal toxicity of ciclosporin, interaction between host and donor marrow, and cytomegalovirus infection might play a role. This study could support the use of recombinant human Epo to accelerate erythropoietic engraftment after BMT.