The Research On Late Onset Pulmonary Complications After Allogeneic Stem Cell Transplantation

Background and ObjectivesHematopoietic stem cell transplantation(HSCT),especially allogeneic HSCT (allo-HSCT),are now applied widely for the treatment of hematological or non-hematological malignancies,aplastic anemia and hereditary diseases,even thought to be the only cure method for some neoplasms and hereditary diseases.In recent years,with the development of technologies in allo-HSCT,patient's long-term survival and quality of life of patients apparently increased.Pulmonary complications occur in 40-60%of patients undergoing allo-HSCT,causing 10-40%of transplant-related deaths and these are recognized as a major cause of morbidity and mortality.Late-oneset pulmonary complications have been paid more and more attentions.Late onset non-infectious pulmonary complications(LONIPCs) occurring beyond 3 months after allo-HSCT is one of the major late onset pulmonary complications after allo-HSCT.The incidence of LONIPCs after allo-HSCT is 3-26% according to the published literatures.Because of its high incidence and poor prognosis,LONIPCs now have become recognized as lifethreatening complications that reduce the recipient's quality of life.Bronchiolitis obliterans(BO) is the most common complication among LONIPCs.The incidence and risk factors of BO have been widely reseached,but there are few researches on it in our country.The pathogenesis of BO has not been identified clearly,and some questions about treatment are crtically needed to be resolved.It has been reported that the macrolide antibiotics could lessen the clinical sympotums of BO and increase the index of pulmonary funcgion test(PFTs),but there are few reports about the mechanism of macrolide antibiotics in the treatment of BO.There is no literature on macrolide antibiotics in the treating of BO in our country.In the present study,we retrospectively evaluated the incidence and the clinical outcome of LONIPCs in 144 patients who underwent allo-HSCT in order to identify possible risk factors;to evaluate the changes of PFTs and the levels of cytokines between before and after the treatment with azithromycin in BO patients,and identify the mechanism of macrolide antibiotics;to explore valid measues of managing LONIPCs and provide guidance and theoretical foundation for clinical practices to enhance the quality of life and prolong the overall survival after allo-HSCT.Patients and Methods1.Clinical data for 170 patients who underwent allo-HSCT at our institution between January 2003 and August 2006 were collected and reviewed retrospectively. Twenty six patients died within 3 months after allo-HSCT,so they were excluded from the analysis.The 144 patients who survived more than 3 months after all-HSCT were eligible for determine the incidence and risk factors of LONIPCs,and include 87 males and 57 females.The patients' median age at transplantation was 30(14 to 53) years.Classification of diseases:acute myeloid leukemia(AML) 49 cases, including:complete remission(CR) 39(including CR1 32,CR2 7),partial remission (PR)/non-remission(NR)10;acute lymphoblastic leukemia(ALL)28 cases, including CR 23(including CR1 16,CR2 7),PR/NR 5;chronic myelogenous leukemia 57,including:chronic phase 49,blast crisis 1,accelerated phase 7;acute biphenotypic leukemia(ABL) 3 cases,including CR 2,NR1;lymphoma leukemia 3; myelodysplastic syndrome 1,chronic lymphocytic leukemia 1,chronic myelogenous -single-cell leukemia(CMML)1.2.Clinical data for 6 patients with BO who underwent allo-HSCT at our institution between January 2008 and December 2008 were collected.The patients included 3 males and 3 females,median age 30(21-41) y.Primary diseases included AML 2,ALL 1,CML-CP 3.All patients underwent allogeniec peripheral stem cell transplantation.Treatment protocol:azithromycin 0.5g/d for three days,followed by 0.25g/d×3 days/week for 8-12 weeks.If patients had the clinical manifestations of cGVHD,glucocorticoids combining with or without ciclosporin A were added the the protocol.Before and after the protocol of azithromycin treatment,PFTs and serum IL-4,IL-10,IFN-γ,TNF-α,TGFβ1 were checked.Serum IL-4,IL-10,IFN-γ,TNF-α, TGFβ1 levels were measused by ELISA.IL-4,IL-10,IFN-γ,TNF-α,TGFβ1 Kits were bought from jitai bio-technology Co.Ltd.3.Statistical analysis:All data were computed with SPSS 13.0 for windows.The differences of means were estimated with independent samples t test.Chi-square tests were used to compare rates,multivariate analysis using Binary Logistic Regression analysis,Kaplan-Meier survival analysis was used to estimate the long term survival of LONIPCs.Paired t-tests were used to compare the values of PFTs and cytokines before and after the treating of azithromycin.P＜0.05 was considered to be statistically significant.Results1.The incidence and risk factors of LONIPCs after allo-HSCT1.1 With the median follow time 1149(90-2151) d,of the 144 patients who for more than 3 months after allo-HSCT,24 patients fulfilled the diagnostic criteria for LONIPCs,and so the incidence is 16.7%.The median time to diagnosis of LONIPCs was 235 days after transplantation(range,116-950 days).Of all the LONPICs,22 patients were dignosed as having cGVHD,including 18 patients with extensive cGVHD.By treated with azithromycin(If patients had cGVHD, glucocorticoids combining with or without ciclosporin A were added),clinical sympotums were relieved in 19 patients(including one patient died of relapse of primary malignant),but the other 5 patients died of respiratory failure due to LONIPCs eventually.1.2 Risk factors of LONIPCs:The influences of many factors,including sex, disease status,HLA compatibility,donor source,conditioning regimen(including total body irradition/total lymphoid irradiation[TBI/TLI]regimen or non-TBI/TLI regimen),CMV antigenaemia,and the presence of acute or chronic GVHD on the development of LONIPCs were analyzed.Three variables were associated with LONIPCs on univariate analysis:CMV antigenaemia(P=0.000),Ⅱ-Ⅳ°aGVHD(P =0.026),cGVHD(P=0.002).Using a Binary Logistic regression model for multivariate analysis,cGVHD(P=0.004,OR=18.804) and CMV antigenaemia(P= 0.000,OR=14.376) was the risk factors of LONIPCs.1.3 Suvial of patients:Of all the LONIPCs patients,5 patients died of died of respiratory failure due to LONIPCs,and only one patient died of relapse of primary malignant;but in patients without LONPICs,36 patients died,the causes of death were relapse of of primary malignant(18 cases),invasive pulmonary fungal infection (9),serious hepatis(1),secondary tongue cancer(1),intracranial hemorrhages(1) and Even's syndrome(1).The 5-year overall survival in LONPICs was 75.0±8.8%,and that in patients without LONPICs was 69.8%±4.3%,overall survival of the LONIPC patients was not longer than that of non-LONIPC patients(P=0.714).1.4 Among the 144 patients with hematologic malignancies,it was notable that the patients with LONIPCs had significantly lower relapse rates of primary malignant disease than did non-LONIPC patients(26/120 vs.1/24,P=0.045).Among the patients with extensive cGVHD,the patients with LONIPCs had significantly lower relapse rates than did non-LONIPC patients(9/32 vs 1/19,P=0.047).2.The research on the effect and mechanism of macrolide antibiotics in the treating of BO after allo-HSCT2.1 The change of PFTs and cytokines after the treatment of azithromycin:When the protocol of treating with azithromycin,the clinical symptoms such as wheezing and dyspnea apparently relieved in 5 patients,but the symptoms exacerbated in one patient because of invasive pulmonary fungal infection.Ater the treatment,an average of 263.33(-210-420)ml improvement in FEV1 was noted,and the FEV1, FEV1%and FEV1/FVC%were significantly improved than those in patients before treating with azithromycin(P＜0.05).2.2 The changes of serum cytokines after the treatment of azithromycin.The levels of serum IL-10 significantly increased(P=0.029) and the levels of serum IFN-γdecreased(P=0.035).DiscussionsWith the developments of alIo-HSCT,late onset complicatons which are closely related to the quality of life and long term survival are now paid more and more attentions.Pulmonary complications occur in 40-60%of patients undergoing allo-HSCT,and now are recognized as a major cause of morbidity and mortality. LONIPCs,which was described firstly by Palmas in 1998,is one of the major late onset pulmonary complications after allo-HSCT.The incidence of LONIPCs after allo-HSCT is 3-26%according to the published literatures.Most BO patients die of progressive repiratory failure and have poor quality of life.The incidence of BO in the present study is 16.7%,which is the same as the reported literatures.Till now,the pathogenesis of LONIPCs is still unclear,but the presence of cGVHD has been taken as a risk factor for developing LONIPCs.The other risk factors include late stage of primary disease,CML,conditioning regimens including Busulphan,rapid reducing of ciclosporin A in GVHD prophylaxis,virus infection in early stage after HSCT and hypogammaglobulinemia.Our results indicated that cGVHD and CMV antigenaemia are the risk factors for developing LONIPCs,which also are the same as the reported literatures.Overall survival of the LONIPC patients was not longer than that of non-LONIPC patients(P=0.714).Of all the LONIPCs patients,5 patients died of died of respiratory failure due to LONIPCs,and only one patient died of relapse of primary malignant;but in patients without LONPICs,18 patients died of the relapse of primary malignant.It was notable that the patients with LONIPCs had significantly lower relapse rates of primary malignant disease than did non-LONIPC patients(26/120 vs.1/24,P=0.045).Among the patients with extensive cGVHD,the patients with LONIPCs had significantly lower relapse rates than did non-LONIPC patients(9/32 vs 1/19,P=0.047).These results indicated that the development of LONIPCs was strongly associated with the graft-versus-leukemia (GVL)effect.BO is the most common complication among LONIPCs.Because of its high incidence and poor prognosis,it has been paied more and more attentions.With regard to the treatment of BO,there is no evidence of evidence-based medicine that which measure is more rational and effective,the majority of treatment is based on a small number of non-controlled studies and expert recommendations.Glucocorticoids and high-dose immunosuppressive agents can used for the treatment of BO,but only a very few patiens can benefit for this protocol,and the therapeutic effect is very poor for serious BO.Macrolide antibiotics have been proven to improve the prognosis of the whole bronchiolitis,and the significant role in their beneficial effect is due to their anti-inflammatory effect rather than anti-bacterial effect.It has been reported that the macrolide antibiotics could lessen the clinical symptoms of BO and increase the index of pulmonary funcgion test(PFTs).In a recent report of eight patients with BO by Khalid M,azithromycin was added at a dose of 500mg per day for 3 days in the first week,and 250 mg three times a week for 12 weeks,and the authors reported an average of 281 ml(20.58%) improvement in FEV1.Susan G also reported that treated with azithromycin at a dose of 250 mg three times a week for 13.5 weeks,5 of 6 patients' PFTs improved.Our results also indicated that ater the treatment,an average of 263.33(-210-420) ml improvement in FEV1 was noted,and the FEV1, FEV1%and FEV1/FVC%were significantly improved than those in patients before treating with azithromycin,which is the same as the reported literatures.IL-10 is an important inhibitory inflammatory cytokines.It can inhibit the abilities of secretion of IL-1,TNF-α,IL-6,IL-8,IL-12 in macrophage or monocyte and the secretion of IFN-γand IL-2 T cell,and it also can reduced the activity of T cells by blocking the expression of MHCⅡmolecules and B7 molecules.In addition, IL-10 also can downregulate MHCⅠmolecule expression,and stimulate the proliferation of Th2-type cells and the differentiation of B cells.IFN-γis secreted by activated T cells and NK cells,it activate macrophages,promote the expression of MHCⅠandⅡmolecules,stimulate Th0 cells differentiating to Th1 cells and inhibit the proliferation of Th2 cell.The data reported by Sugiyama indicated that azithromycin increased the IL-10 production by murine dendritic cells.Tasi,et al reported that azithromycin effectively reduced lung inflammation by reducing increasing IFN-γin lung tisue and improving clearance of apoptotic cells by macrophages.Our data showed that serum IL-10 significantly increased after the treating of azithromycin,which is the same as the results of Tasi.But IFN-γlevel significantly decreased after treatment,which is not consistent with the repored literatures.The possible reason may be that our data are gained from serum and Tasi's data from lung tissue.It can conclude that azithromycin can improve the clinical symptoms of BO by regulating the levels of IL-10 and IFN-γ.