A single-center study on the distribution and antibiotic resistance of pathogens causing bloodstream infection in patients with hematological malignancies / 中华血液学杂志

Objective: To study the incidence of bloodstream infections, pathogen distribution, and antibiotic resistance profile in patients with hematological malignancies. Methods: From January 2018 to December 2021, we retrospectively analyzed the clinical characteristics, pathogen distribution, and antibiotic resistance profiles of patients with malignant hematological diseases and bloodstream infections in the Department of Hematology, Nanfang Hospital, Southern Medical University. Results: A total of 582 incidences of bloodstream infections occurred in 22,717 inpatients. From 2018 to 2021, the incidence rates of bloodstream infections were 2.79%, 2.99%, 2.79%, and 2.02%, respectively. Five hundred ninety-nine types of bacteria were recovered from blood cultures, with 487 (81.3%) gram-negative bacteria, such as Klebsiella pneumonia, Escherichia coli, and Pseudomonas aeruginosa. Eighty-one (13.5%) were gram-positive bacteria, primarily Staphylococcus aureus, Staphylococcus epidermidis, and Enterococcus faecium, whereas the remaining 31 (5.2%) were fungi. Enterobacteriaceae resistance to carbapenems, piperacillin/tazobactam, cefoperazone sodium/sulbactam, and tigecycline were 11.0%, 15.3%, 15.4%, and 3.3%, with a descending trend year on year. Non-fermenters tolerated piperacillin/tazobactam, cefoperazone sodium/sulbactam, and quinolones at 29.6%, 13.3%, and 21.7%, respectively. However, only two gram-positive bacteria isolates were shown to be resistant to glycopeptide antibiotics. Conclusions: Bloodstream pathogens in hematological malignancies were broadly dispersed, most of which were gram-negative bacteria. Antibiotic resistance rates vary greatly between species. Our research serves as a valuable resource for the selection of empirical antibiotics.

Influence of FLT3-ITD Mutation and ITD Length on the Outcome on Patients with Acute Myeloid Leukemia / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the influence of FLT3-ITD mutation and ITD length on the overall survival (OS) and relapse free survival(RFS) in patients with non-M3 acute myeloid leukemia.</p><p><b>METHODS</b>Clinical features and therapeutic effect were retrospectively analyzed in 75 AML patients with FLT3-ITD mutation and 76 FLT3-ITD AML patients with a normal karotype from June 2011 to April 2016. Genomic DNA was amplified by PCR, and FLT3-ITD mutation length was analyzed by DNA sequencing in 40 patients.</p><p><b>RESULTS</b>AML patients with FLT3-ITD mutation had higher WBC count and the ratio of BM blast cells at initial diagnosis was also higher than those in AML patients without FLT3-ITD mutation (95.13 vs 10.85)(P<0.01); 72% vs 59%(P<0.01). The CR rates in AML patients with FLT3-ITD mutation less than those in AML patients without FLT3-ITD mutation(70.42% vs 94.7%)(P<0.01). OS (P<0.01) and RFS (P<0.01) were significantly increased in patients with AML who received allo-HSCT as compared with the patients who received consolidation chemotherapy and similar to AML patients without FLT3-ITD mutation who received HSCT. Patients with maintenance sorafenib after HSCT had longer OS (P<0.05) and RFS (P<0.05) than controls. ITDs exceeding 60 bp in length were associated with decreasing OS as compared with shorter ITD in AML patients with FLT3-ITD mutation (P<0.05). OS and RFS were similar among the 2 groups receiving consolidation chemotherapy. Besides, the patients with allo-HSCT had shorter ITDs and longer OS than ITDs exceeding 60 bp (P<0.05) and similar to AML patients without FLT3-ITD mutation.</p><p><b>CONCLUSION</b>AML patients with FLT3-ITD mutation has poorer outcome, among which the prognosis was worse in patients with ITD exceeding 60 bp, and the chemotherapy alone can not improve the prognosis of FLT3-ITD. Allo-HSCT is an effective treatment for AML patients with FLT3-ITD mutation; Sorafenib appears to be an effective maintenance therapy after allo-HSCT in FLT3-ITD AML.</p>

Clinical significance of monitoring BK polyomavirus in patients after hematopoietic stem cell transplantation / 中国实验血液学杂志

This study was aimed to establish a method for rapid detecting BK polyomavirus (BKV) and to investigate the feasibility and value used in leukemia patients undergoing hematopoietic stem cell transplantation. Primers were designed according to BKV gene sequence; the quantitative standards for BKV and a real-time fluorescent quantitative PCR for BKV were established. The BKV level in urine samples from 36 patients after hematopoietic stem cell transplantation were detected by established method. The results showed that the standard of reconstructed plasmid and real time fluorescent quantitative PCR method were successfully established, its good specificity, sensitivity and stability were confirmed by experiments. BKV was found in 55.56% of urine samples, and the BKV load in urine was 2.46 × 10(4) - 7.8 × 10(9) copy/ml. It is concluded that the establishment of real-time fluorescent quantitative PCR for BKV detection provides a method for early diagnosis of the patients with hemorrhagic cystitis after hematopoietic stem cell transplantation.

The outcome and safety of mesenchymal stem cells from bone marrow of a third party donor in treatment of secondary poor graft function following allogeneic hematopoietic stem cell transplantation / 中华血液学杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy and safety of bone marrow-derived mesenchymal stem cells (MSC) from a third party donor for secondary poor graft function (PGF) following allogeneic hematopoietic stem cell transplantation(allo-HSCT).</p><p><b>METHODS</b>Five patients with secondary PGF were treated with MSC at a dose of 1 x 10(6)/kg body weight at a median of 47 days (35 to 61) after secondary PGF. MSC were derived from bone marrow (BM) of HLA-disparate third party donors, cultured in vitro and infused without HSC. If absolute neutrophil cell (ANC) and platelet counts (PLT) did not reach the standardization of > 1.5 x 10(9)/L and > 50.0 x 10(9)/L, respectively, within 28-30 days after the first MSC treatment, a second MSC treatment was required.</p><p><b>RESULTS</b>MSC were infused once in one patient and twice in four patients with an interval of 28 to 30 days. All patients obtained ANC and PLT recovery at a median of 34 (25 to 49) days and 47 (26 to 54) days, respectively, without toxic side effects within follow-up periods of median 761 (204-1491) days. Three patients developed Epstein-Barr virus (EBV) reactivation at 42, 48, 108 days after MSC infusion, respectively and two of the three coverted to posttransplant lymphoproliferative disorders (PTLD).</p><p><b>CONCLUSION</b>MSC from a third party donor are effective to patients with secondary PGF following allo-HSCT, whether it might increase the risk of EBV reactivation and EBV-associated PTLD need further observation.</p>

Clinical features and prognosis in 49 patients with Castleman's disease / 中国医学科学院学报

<p><b>OBJECTIVE</b>To analyze the clinical features and prognosis of patients with Castleman's disease (CD).</p><p><b>METHODS</b>Clinical and pathological data of 49 patients with CD diagnosed in Peking Union Medical College Hospital from January 1990 to December 2007 were retrospectively analyzed.</p><p><b>RESULTS</b>In patients with uni-centric CD (UCD), hyaline vascular type had the highest percentage (88.2%, 15/17), which was significantly higher than that of either plasma cell type (5.9%, 1/17) or mixed cell type (5.9%, 1/17) (P < 0.05). In patients with multicentric CD (MCD), there were no significant differences among the percentages of different histopathologic types. In contrast to patients with UCD, patients with MCD were relatively older and had more typical clinical features, more frequent complications, and more frequent abnormal laboratory results. Twenty patients with UCD achieved complete remission (CR) after surgery, and their complications also disappeared one month later. Twenty-three out of 29 patients with MCD were treated with chemotherapy; only 6 patients achieved CR and 9 achieved partial remission (PR), and the overall response rate was 65.2%. Two patients who initially did not responded to chemotherapy achieved CR after the addition of rituximab.</p><p><b>CONCLUSIONS</b>The clinical features of CD are multifarious and nonspecific, and diagnosis is exclusively depended on histopathology. UCD has a good prognosis after surgery, while MCD often poorly responds to chemotherapy and has a relatively poor prognosis. New drugs and clinical trials are needed to improve the outcome of MCD.</p>