Definition of myeloid engraftment after allogeneic hematopoietic stem cell transplantation

Neutrophil counts continued to rise after reaching 0.5x10(9)/L in 78 allograft recipients receiving granulocyte colony-stimulating factor (G-CSF) post-transplant. This was confirmed in 44 subsequent patients not receiving G-CSF. This suggests that the first day of neutrophils >or=0.5x10(9)/L can be considered a valid definition of myeloid recovery after allogeneic transplantation.     

Assessment of hematologic progenitor engraftment by complete reticulocyte maturation parameters after autologous and allogeneic hematopoietic stem cell transplantation

BACKGROUND AND OBJECTIVES: Hematopoietic restoration after marrow ablation is initiated by the erythroid compartment. However, the absolute microscope counts or corrected percentage of reticulocytes have proven to be poor markers of hematopoietic engraftment. Some reports have highlighted the usefulness of automatic flow cytometry methods to determine highly fluorescent reticulocytes, or mean fluorescence index. In this series of 60 hematopoietic stem cell transplants, we sought the normal kinetics throughout the post-transplant period of the following reticulocyte maturing parameters: highly fluorescent reticulocytes (RETH), immature reticulocyte fraction (IRF), mean fluorescence index (MFI) and also mean reticulocyte volume (MRV). DESIGN AND METHODS: Sixty consecutive patients undergoing allogeneic bone marrow (30 cases) and autologous mobilized stem cell transplantation (30 cases) were studied. Parameters of reticulocyte maturation were measured every other day from the beginning of the conditioning regimen until myeloid engraftment. RESULTS: Nadir values for the analyzed reticulocyte parameters were found between days +4 and +7 and thereafter, increases in these reticulocyte parameters appeared earlier than the rise in neutrophils. We considered erythroid engraftment to have occurred on the day when RETH reached 3%, IRF 10%, MFI 10 and MRV 110 fL. These cut-offs were assigned considering the 25% quartile for each parameter on the day that the myeloid engraftment occurred. The median engraftment days for RETH were +9 and +16, for IRF +9 and +13, for MFI +9 and +13 and for MRV +11 and +13 in autologous and allogeneic procedures, respectively. When compared to standard neutrophil engraftment, IRF and MFI engraftment occurred significantly earlier in all patients. Remarkably, we found a statistical correlation between the day a reticulocyte parameter reached its cut-off and the subsequent day of absolute neutrophil count (ANC) recovery for MFI after allogeneic transplants and for MRV after autologous procedures (p < 0.001 and p= 0.02, respectively). Of all the clinical parameters tested, only the number of infused CD34 cells showed a statistical influence on erythroid engraftment in autologous transplant. INTERPRETATION AND CONCLUSIONS: Early reticulocytes appear sooner than neutrophils after both autologous and allogeneic transplants, and any determined reticulocyte parameter can reliably measure this fraction. Nevertheless, our results show that MRV and MFI cut-offs are useful for determining subsequent myeloid engraftment. These findings could be relevant to decision-making in those patients with primary graft failure heralded by an absence of increasing values of MFI and MRV, indicating very low production of reticulocytes from the graft, who could, therefore, benefit from earlier rescue therapy.     

Multilineage hematopoietic engraftment after allogeneic peripheral blood stem cell transplantation without conditioning in SCID patients

Successful stem cell transplantation for patients with severe combined immunodeficiency (SCID) from matched family donors without conditioning results in engraftment of T lymphocytes. B lymphocytes engraft in only 50% of the cases, while myelopoiesis and erythropoiesis remain of host origin. Full hematopoietic engraftment was reported in one case after bone marrow transplantation without conditioning for a SCID patient. We studied three SCID patients who were transplanted with unmodified mobilized peripheral blood from HLA-identical family sex-mismatched members. They received megadoses of stem cells (18-23 x 10(6)CD34/kg). In contrast to the expected mixed chimerism that usually occurs in the absence of conditioning, we found in our patients 100% donor cell engraftment based on fluorescence in situ hybridization (FISH) and microsatellite techniques. Subset analysis of the engrafted cells using a multiparametric system enabling a combined analysis of morphology, immunophenotyping and FISH showed that both T and B lymphocytes and myeloid cells were of donor origin in two patients, while T lymphocytes and myeloid cells were of donor origin in the third. In the two cases with ABO incompatibility, erythroid engraftment was evidenced by blood group conversion from recipient to donor type. Multilineage donor engraftment is possible in SCID patients even without conditioning.     

Pulmonary complications after allogeneic hematopoietic stem cell transplantation

We investigated the occurrence of pulmonary complications in patients who underwent allogeneic hematopoietic stem cell transplantation at our institution. Pulmonary complications were observed in 12 out of 60 patients. Interstitial pneumonia developed in 12 cases: 7 idiopathic, 2 cytomegalovirus-associated, 1 P. carinii, 1 HSV, and 1 HHV-6-associated. HSV- and HHV-6-associated pneumonias were exhibited 100 days after transplantation. PCR analysis was diagnostically useful for detection of viral DNA in bronchial alveolar lavage fluid. Respiratory disease with airway obstruction was observed in 4 patients with chronic graft-versus-host disease, and all 4 had a history of interstitial pneumonia. Three patients died of respiratory failure. Mycobacicrium avium complex was detected in 2. Exacerbation of respiratory failure may be associated with mycobacterial infection.     

Pulmonary function after allogeneic hematopoietic stem cell transplantation

This study was undertaken to identify the factors influencing pulmonary function in patients who underwent hematopoietic stem cell transplantation (HCT). Pulmonary function tests were evaluated before and after HCT in 51 adult patients who underwent HCT between 1993 and 1998. The patients with hematologic malignancies were given total body irradiation. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine A and short-term methotrexate. Six patients suffered from acute GVHD above grade II and 27 patients suffered from chronic GVHD. The post-transplant % diffusing capacity (%DLco) 100 days after HCT was significantly lower than pretransplant values (82 +/- 21% versus 71 +/- 15%, p < 0.01). The %DLco at 100 days was significantly lower in patients with chronic GVHD than in patients without chronic GVHD (66 +/- 16% versus 77 +/- 9%, p < 0.05). These findings suggested chronic GVHD is related to the decreased %DLco values observed 100 days after HCT.     

Heart failure after allogeneic hematopoietic stem cell transplantation

Background

Heart failure (HF) occurring after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is rare but severe. We examine the role of pre-HSCT therapeutic exposures, conditioning regimens, pre-HSCT comorbidities, severe transplant-related complications, and post-HSCT cardiovascular risk factors in the development of heart failure after allo-HSCT.

Methods

A nested case-control study was designed. Cases with HF and controls matched for age, year of allo-HSCT, and length of follow-up were identified from a cohort of 2455 patients who underwent allo-HSCT between 2000 and 2011 for hematologic malignancies.

Results

Forty-two patients suffered from HF; mean age at presentation was 35 years (± 14 years) and mean time to presentation was 5 months (± 9 months) post-HSCT. The number of pre-HSCT cycles of chemotherapy was significantly greater (7 vs. 5 courses, P = 0.023). Cases were significantly more likely to have severe acute GVHD (≥ grade III), hemorrhagic cystitis (≥ grade 2), and multiple severe transplant-related complications compared with controls (42.9% vs. 20.4%, P = 0.008). Multivariate analysis revealed that pre-HSCT cycles of chemotherapy of ≥ 5 courses (OR = 3.5, P = 0.003) and two or more severe transplant-related complications (OR = 3.6, P = 0.003) were independently associated with HF.

Conclusions

These results identify the individuals who are at higher risk of developing HF after allo-HSCT. We should pay more attention to these patients and more active management would be reasonable.     

Airflow obstruction after myeloablative allogeneic hematopoietic stem cell transplantation

Despite advances in the management of myeloablative allogeneic hematopoietic stem cell transplants, airflow obstruction (AFO) remains a significant complication. We conducted a 12-year study to examine the recent epidemiology of AFO and its associated mortality. Using the rate of percent predicted FEV1 decline after transplant, we defined AFO as a more than 5% per year decline in percent predicted FEV1 with the lowest post-transplant FEV1/FVC ratio less than 0.8. New obstruction was more frequent than previous estimates (26% overall, 32% among patients with chronic graft-versus-host disease [GVHD]) and was significantly associated with older age at transplant, lower pretransplant FEV1/FVC ratio, history of both acute and chronic GVHD, and respiratory viral infection within the first 100 days after transplant. AFO was associated with significant attributable mortality rates of 9% at 3 years, 12% at 5 years, and 18% at 10 years after transplant, which were much higher for the subpopulation of patients with chronic GVHD (22% at 3 years, 27% at 5 years, and 40% at 10 years). These results suggest that the incidence of AFO may have been underestimated previously, and its presence significantly increases the mortality of long-term survivors of myeloablative allogeneic hematopoietic stem cell transplant patients.     

Acute eosinophilic pneumonia after allogeneic hematopoietic stem cell transplantation

A 55-year old woman with multiple myeloma was treated with hematopoietic stem cell transplantation (HSCT). She developed cutaneous and hepatic graft-vs-host disease (GVHD). Sixty-five days after HSCT, acute respiratory failure occurred. A thoracic computed tomography scan showed bilateral patchy infiltrates. Bronchoalveolar lavage revealed 40% eosinophils on differential cell count with no infectious pathogens. These findings were in favor of acute eosinophilic pneumonia. High-dose steroid treatment was started, which had a rapid and lasting favorable course. After HSCT, clinicians should be aware that acute eosinophilic pneumonia mimics infectious pneumonitis and can be associated with GVHD.     

Human metapneumovirus infection after allogeneic hematopoietic stem cell transplantation

Background

The clinical characteristics of human metapneumovirus (hMPV)-associated lower respiratory tract infection (LRTI) after allogeneic hematopoietic stem cell transplantation (HSCT) is not well described. We describe the clinical course in eight HSCT recipients suffering from hMPV infection.

Methods

We prospectively included all patients with hMPV-associated LRTI after allogeneic HSCT during a period of 1?year. hMPV was diagnosed by multiplex polymerase chain reaction (PCR) from bronchoalveolar lavage (BAL).

Results

Eight patients with hMPV-associated LRTI were identified from 93 BAL samples. Three of the eight patients had co-infections with other pathogens. The median age of the patients was 45?years [interquartile range (IQR) 36.8?C53.5], the median time posttransplant was 473?days (IQR 251?C1,165), 5/8 patients had chronic graft-versus-host disease (cGvHD), and 6/8 patients received immunosuppression. Chest computed tomography (CT) scanning showed a ground-glass pattern in 7/8 patients. Seven of eight patients required hospitalization due to severe symptoms and hypoxemia. All were treated with intravenous immunoglobulin (IVIG), which was combined with oral ribavirin in six patients. The mortality rate was 12.5?% (1/8).

Conclusions

hMPV-associated LRTI in allogeneic HSCT recipients are not uncommon and present with unspecific respiratory symptoms, ground-glass pattern in CT scanning, and co-infection.     

High incidence of engraftment syndrome after haploidentical allogeneic stem cell transplantation

We determined the incidence, clinical manifestations, and outcomes of engraftment syndrome (ES) in haploidentical stem cell transplantation (SCT) recipients. We compared the incidence of ES between the patient group that received haploidentical SCT (n = 516) and the patient group that received HLA‐identical sibling SCT (n = 393). The transplantations were performed in the Peking University People's Hospital in the period between October 2001 and October 2012. The ES incidence data were collected retrospectively. Patients that presented non‐infectious fever or skin rash within the 24‐h window before or after the beginning of neutrophil recovery were diagnosed with ES in accordance with the Maiolino criteria. ES incidence in haploidentical SCT recipients (21.9%) was significantly higher than that in HLA‐identical sibling SCT recipients (2.0%; P < 0.001). Major symptoms included fever (119/121, 98.3%), skin rash (98/121, 81.0%), and diarrhea (51/121, 42.1%), with the median time of +10 d (range: 6–20 d). The median C‐reactive protein level of the ES group (99.0 mg/L; n = 13) was significantly higher than that of the non‐ES group (13.9 mg/L; n = 38; P < 0.001). Similarly, the results showed that the median C3 plasma concentration of the ES group (1.30 g/L) was higher than that of the non‐ES group (1.16 g/L, P = 0.003). ES was not associated with non‐relapse mortality or overall survival. High incidence of ES was observed in haploidentical SCT recipients; however, ES did not predict poor clinical outcomes.     

Immune reconstitution and tolerance after allogeneic hematopoietic stem cell transplantation

We have evaluated recovery of CD56 positive and other cell types following allogeneic stem cell transplantation and have found that the recovery of CD56 positive cells was faster than other lymphoid cells after allogeneic stem cell transplantation, while the recovery of CD4 positive cells was markedly delayed. Chimerism analysis showed that mixed chimerism was often observed in younger (<30 years old) patients. Mixed chimerism in older (> or =30 years old) patients was associated with rejection and relapse, while this was not found in younger patients. Among the chimerism of various cell populations, donor-derived CD56-positive cells are important in early engraftment when determined in allogeneic nonmyeloablative stem cell transplantation (allo-NST), regardless of the proportion of donor-derived CD3-positive cells. Complementarity-determining region three (CDR3) size spectratyping in T-cell receptor (TCR) chain subfamilies (Vbeta) showed that high level of diversity in TCR Vbeta repertoire is important for a late rejection and skewed TCR Vbeta repertoire is correlated with the occurrence of graft-versus-host disease (GVHD) especially chronic GVHD. Expression of inhibitory natural killer (NK) cell receptors such as CD158b and CD94/NKG2A on peripheral CD3-negative and -positive cells were increased in parallel with GVHD. Interestingly, these cells appeared to control GVHD, while preserving graft-versus-leukemia (GVL) effect. Analysis of cytokine gene expression in peripheral blood mononuclear cells showed that type 1 helper T cells (Th1)-derived cytokines increased in severe GVHD, while Th2-derived cytokines such as IL-4, IL-10 and IL-13 increased in mild GVHD. These results indicate that Th2 cells suppress GVHD, although Th1 cells augment GVHD. Taken together, evaluation of immune reconstitution and tolerance in patients receiving allogeneic stem cell transplantation from the various viewpoints is essential and useful to obtain better clinical outcome.     

Factors affecting thymic function after allogeneic hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) is followed by profound immunodeficiency. Thymic function is necessary for de novo generation of T cells after HSCT. Circulating CD45RA(+) naive T-cell levels are predictive of antigen-specific T-cell responses in the absence of graft-versus-host disease (GVHD). These T cells may not represent recent thymic emigrants, since naive T cells may maintain this phenotype if not antigen-activated. To accurately measure thymic output after HSCT and determine the factors that influence thymic function, T-cell receptor excision circles (TRECs) were examined in CD4(+) and CD8(+) cells from a cross-section of patients following HSCT. TREC levels rose weeks after HSCT and could be detected in patients 6 years after HSCT. TREC levels correlated with the frequency of phenotypically naive T cells, indicating that such cells were not expanded progeny of naive T cells present in the donor graft. Chronic GVHD was the most important factor that predicted low TREC levels even years after HSCT. Patients with a history of resolved GVHD had decreased numbers of TREC, compared with those with no GVHD. Because few adults had no history of GVHD, it was not possible to determine whether age alone inversely correlated with TREC levels. Recipients of cord blood grafts had no evidence of decreased TREC induced by immunosuppressive prophylaxis drugs. Compared with unrelated donor grafts, recipients of matched sibling grafts had higher TREC levels. Collectively, these data suggest that thymopoiesis is inhibited by GVHD. Larger studies will be needed to determine the independent contributions of age and preparative regimen to post-transplant thymopoietic capacity.     

Actinomycosis after allogeneic hematopoietic stem cell transplantation despite penicillin prophylaxis

Actinomycosis is a rare chronic and multifaceted disease caused by Actinomyces species frequently mimicking malignancy or other chronic granulomatous lung diseases. We report 4 original presentations of actinomycosis arising under supposed penicillin prophylaxis in allogeneic stem cell transplantation recipients.