[Analysis of Pathogenic Bacterial Spectrum, Drug Resistance and Risk Factors for Mortality of Bloodstream Infection in Patients with Hematologic Diseases].

OBJECTIVE: To analyze the pathogenic bacterial spectrum, drug resistance, and risk factors associated with multidrug-resistant bacterial infection and mortality in patients with hematologic diseases complicated by bloodstream infections, so as to provide reference for rational drug use and improving prognosis. METHODS: Positive blood culture specimens of patients with hematologic diseases in two Class A tertiary hospitals of Shanxi province from January 2019 to December 2021 were retrospectively analyzed. Pathogen distribution, drug resistance and outcomes of patients with bloodstream infection were investigated, then the multivariate logistic analysis was performed to analyze the risk factors of multidrug-resistant bacterial infection and factors affecting prognosis. RESULTS: 203 strains of pathogens were identified, mainly Gram-negative bacteria (GNB) (69.46%, 141/203), of which Escherichia coli (E.coli) had the highest incidence (41.13%, 58/141), followed by Klebsiella pneumoniae (20.57%, 29/141) and Pseudomonas aeruginosa (12.77%, 18/141). Extended-spectrum beta-lactamase (ESBL)-producing E.coli and Klebsiella pneumoniae were 46.55% (27/58) and 37.93% (11/29), respectively. Carbapenem-resistant Gram-negative bacteria accounted for 10.64% (15/141). And Gram-positive bacteria accounted for 27.59% (56/203), Staphylococcus epidermidis, Streptococcus pneumoniae, and Staphylococcus aureus were the most frequently isolated pathogen among Gram-positive bacteria (14.29%, 12.50% and 10.71%, respectively), of which methicillin-resistant Staphylococcus aureus accounted for 33.33% (2/6), coagulase-negative staphylococci accounted for 87.50% (7/8), without vancomycin- or linezolid-resistant strain. Additionally, fungi accounted for 2.95% (6/203), all of which were Candida. Multidrug-resistant Gram-negative bacteria (MDR-GNB) accounted for 53.90% (76/141). Duration of neutropenia >14 days was a risk factor for developing MDR-GNB infection. The 30-day all-cause mortality was 10.84%. Multivariate logistic regression analysis showed that the significant independent risk factors for mortality were age≥60 years (P <0.01, OR =5.85, 95% CI: 1.80-19.07) and use of vasopressor drugs (P <0.01, OR =5.89, 95% CI: 1.83-18.94). CONCLUSION: The pathogenic bacteria of bloodstream infection in patients with hematological diseases are widely distributed, and the detection rate of multidrug-resistant bacteria is high. The clinicians should choose suitable antibiotics according to the results of bacterial culture and antibiotic susceptibility test.

[Clinical Characteristics and Risk Factors for 30-Day Mortality in Patients with Hematologic Diseases Infected by Carbapenem-Resistant Organisms].

OBJECTIVE: To explore the clinical characteristics of hospitalized patients with hematologic diseases complicated with carbapenem-resistant organisms (CRO) infection and analyze the risk factors of 30-day all-cause mortality. METHODS: The clinical data and laboratory test data of 77 hospitalized patients with hematologic diseases complicated with CRO infection in department of hematology of the Third Hospital of Shanxi Medical University from January 2015 to December 2020 were retrospectively analysed, the risk factors of 30-day all-cause mortality after CRO infection were analyzed by multivariate logistic regression. RESULTS: Among the total of 77 patients with hematologic diseases complicated with CRO infection, 29 died and 48 survived within 30 days of infection, with a case fatality rate of 37.66%. A total of 93 strains of CRO were isolated from these patients, of which Acinetobacter baumannii had the highest detection rate (25.81%, 24/93), followed by Pseudomonas aeruginosa (18.28%, 17/93). The lung was the most common site of CRO infection. The detected pathogens were highly resistant to carbapenems, and 64.52% (60/93) of the pathogens were resistant to imipenem with minimum inhibitory concentration (MIC)≥16 µg/ml. The results of the univariate analysis showed that albumin concentration <25 g/L (P =0.048), serum creatinine concentration≥120 µmol/L (P =0.023), age-adjusted Charlson comorbidity index (ACCI) (P =0.037) and primary treatments (supportive treatment, immunosuppressive therapy, chemotherapy, HSCT) (P =0.048) were significantly associated with 30-day all-cause mortality after infection. The results of multivariate logistic regression analysis showed that when CRO infection confirmed, albumin concentration <25 g/L (P =0.014, OR=6.171), serum creatinine concentration≥120 µmol/L (P =0.009, OR=10.867) were independent risk factors for 30-day mortality of patients with hematologic diseases complicated with CRO infection. CONCLUSION: The mortality rate of CRO-infected patients with hematologic diseases is high. The detected pathogenic bacteria are highly resistant to imipenem. The albumin concentration <25 g/L and the serum creatinine concentration≥ 120 µmol/L at diagnosis of CRO infection were independent risk factors for 30-day mortality of the patients with hematologic diseases.

[Clinical Characteristics and Nomogram Model of Nosocomial Infection in Patients with Newly Diagnosed Multiple Myeloma].

OBJECTIVE: To explore the clinical characteristics of nosocomial infection in newly diagnosed multiple myeloma(NDMM) patients, and establish a predictive nomogram model. METHODS: The clinical data of 164 patients with MM who were treated in Shanxi Bethune Hospital from January 2017 to December 2021 were retrospectively analyzed. The clinical characteristics of infection were analyzed. Infections were grouped as microbiologically defined infections and clinically defined infections. Univariate and multivariate regression models were used to analyze the risk factors of infection. A nomogram was established. RESULTS: 164 patients with NDMM were included in this study, and 122 patients (74.4%) were infected. The incidence of clinically defined infection was the highest (89 cases, 73.0%), followed by microbial infection (33 cases, 27.0%). Among 122 cases of infection, 89 cases (73.0%) had CTCAE grade 3 or above. The most common site of infection was lower respiratory in 52 cases (39.4%), upper respiratory tract in 45 cases (34.1%), and urinary system in 13 cases (9.8%). Bacteria(73.1%) were the main pathogens of infection. Univariate analysis showed that ECOG ≥2, ISS stage Ⅲ, C-reactive protein ≥10 mg/L, serum Creatinine ≥177 µmol/L had higher correlation with nosocomial infection in patients with NDMM. Multivariate regression analysis showed that C-reactive protein ≥10 mg/L (P＜0.001), ECOG ≥2 (P=0.011) and ISS stage Ⅲ （P=0.024） were independent risk factors for infection in patients with NDMM. The nomogram model established based on this has good accuracy and discrimination. The C-index of the nomogram was 0.779（95%CI: 0.682-0.875）. Median follow-up time was 17.5 months, the median OS of the two groups was not reached (P=0.285). CONCLUSION: Patients with NDMM are prone to bacterial infection during hospitalization. C-reactive protein ≥10 mg/L, ECOG ≥2 and ISS stage Ⅲ are the risk factors of nosocomial infection in NDMM patients. The nomogram prediction model established based on this has great prediction value.

Anti-BCMA CAR-T Cell Therapy in Relapsed or Refractory Multiple Myeloma Patients with Impaired Renal Function.

Anti-B cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T-cell therapy is effective and well-tolerated for refractory or relapsed multiple myeloma (RRMM). The purpose of the present study was to analyze efficacy in RRMM patients with renal impairment treated by anti-BCMA CAR-T cell therapy. A total of 59 RRMM patients were selected, and divided into impaired renal function (IRF) group [baseline estimated glomerular filtration rate (eGFR) < 90 mL/min/1.73 m2 (n=18)] and normal renal function (NRF) group (baseline eGFR ≥ 90 mL/min/1.73 m2, n=41). For patients with IRF, eGFR at the 6th month post-CAR-T cells infusion was significantly higher than the baseline (P<0.05). The multivariate analysis showed that light chain type and beta-2 micro-globulin (beta-2M) were associated factors with the decrease of serum creatinine. Median progression-free survival (PFS) in the NRF group and IRF group was 266 days and 181 days respectively. Overall survival (OS) in the NRF group and IRF group was 877 days and 238 days respectively. There was no significant difference in the objective response rate (ORR) between the IRF group and the NRF group. It is suggested that CAR-T cells therapy could improve the renal function during the treatment of RRMM. The renal function could be more significantly improved in RRMM patients with light chain type than with other types.