Catherine Cordonnier, Sigrun Einarsdottir, Simone Cesaro, Roberta Di Blasi, Malgorzata Mikulska, Christina Rieger, Hugues de Lavallade, Giuseppe Gallo, Thomas Lehrnbecher, Dan Engelhard, Per Ljungman, European Conference on Infections in Leukaemia group

Infection is a main concern after haemopoietic stem cell transplantation (HSCT) and a major cause of transplant-related mortality. Some of these infections are preventable by vaccination. Most HSCT recipients lose their immunity to various pathogens as soon as the first months after transplant, irrespective of the pre-transplant donor or recipient vaccinations. Vaccination with inactivated vaccines is safe after transplantation and is an effective way to reinstate protection from various pathogens (eg, influenza virus and Streptococcus pneumoniae), especially for pathogens whose risk of infection is increased by the transplant procedure.

Abstract Background Pseudomonas aeruginosa is an unusual pathogen in community-acquired pneumonia, especially in previously healthy adults, but often indicates poor prognosis. Case presentation We report a previously healthy patient who developed severe community-acquired pneumonia (CAP) caused by P. aeruginosa. He deteriorated to septic shock and multiple organ dysfunction syndrome (MODS) quickly, complicated by secondary hematogenous central nervous system (CNS) infection. After 1 month of organ support and antipseudomonal therapy, he had significant symptomatic improvement and was discharged from hospital. During treatment, the pathogen developed resistance to carbapenems quickly and the antibiotic regimen was adjusted accordingly. Conclusions According to our case and related literature review, we conclude that more attention should be paid to community-acquired Pseudomonas aeruginosa pneumonia, because of its rapid progression and poor prognosis.…

Abstract Background Tumor necrosis factor-α (TNF-α) antagonists, most of which are monoclonal antibodies, became a widespread treatment for autoimmune diseases such as rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel diseases, psoriasis, psoriatic arthritis, hidradenitis suppurativa and uveitis. Their use is based on the blockage of TNF-α, which plays an important role in granulomas formation, development of phagosomes, activation and differentiation of macrophages, immune response against viral pathogens. The multiple adverse effects of TNF-α inhibition have been identified, including a two-to four-fold increased risk of active tuberculosis and other granulomatous conditions and an increased occurrence of some other serious bacterial, fungal and certain viral infections. Case presentation A 34-year-old male patient with disseminated varicella and pneumonitis was admitted to our hospital. The diagnosis of varicella was established serologically by enzyme immunoassay (EIA) and by polymerase chain reaction confirmation of the virus in vesicular fluid. The patient has been receiving adalimumab and methotrexate for the last 3 years due to ankylosing spondylitis and was seropositive to varicella zoster virus prior to the introduction of TNF-α antagonists. Acyclovir was administered for 10 days with the resolution of clinical illness and radiological signs of pneumonitis. Conclusion Due to the use of biological agents, particularly TNF-α inhibitors, as a well-established therapy for some autoimmune diseases, new potential adverse events can be expected in the future and we wanted to point out one of them. To our knowledge this is the first case of recurrent disseminated varicella in a patient taking TNF-α antagonists.…

Abstract Introduction A woman infected by carbapenem-resistant Klebsiella pneumoniae is reported in this study. Case report Tigecycline and meropenem combination was used, and indeed, in vitro checkerboard synergy test confirmed the antagonism between the two antibiotics. Thus, meropenem was ceased and single high-dose tigecycline was successful against the infection. Subsequent experiments showed that the isolates of the KPC-2-producing K. pneumoniae ST11 clone caused the infection. Conclusion Therefore, tigecycline and meropenem combination should be used with caution.…

Bian, X., Liu, X., Chen, Y., Chen, D., Li, J., Zhang, J.

Background: Colistin-based combination therapy has become an important strategy to combat the carbapenem-resistant Acinetobacter baumannii (CRAB). However, the optimal dosage regimen selection for the combination with the maximum efficacy is challenging.Method: Checkerboard assay was employed to evaluate the synergy of colistin in combination with meropenem, rifampicin, fosfomycin and minocycline against nine carbapenem-resistant A. baumannii (Minimum inhibitory concentration of meropenem [MICMEM]≥32 mg/L) isolated from Chinese hospital-acquired pneumonia (HAP) patients. Static time-kill assay, in vitro dynamic pharmacokinetic/pharmacodynamic (PK/PD) model and semi-mechanistic PK/PD modeling were conducted to predict and validate the synergistic effect of the most efficacious combination.Results: Both checkerboard and static time-kill assays demonstrated superior synergistic effect of colistin-meropenem combination against all CRAB isolates. In the in vitro PK/PD model, the dosage regimen of 2 g meropenem daily via 3-h infusion combined with steady-state 1 mg/L colistin effectively suppressed the bacterial growth at 24 h with 2-log10 decrease, compared to the initial inocula against two CRAB isolates. The semi-mechanistic PK/PD model predicted that more than 2 mg/L colistin combined with meropenem (2 g, 3-h infusion) was required to achieve the killing below the limit of detection (

Zhi Ruan, Qingyang Sun, Huiqiong Jia, Chenyun Huang, Weili Zhou, Xinyou Xie, Jun Zhang

Abstract Background To determine the epidemiology and risk factors for nosocomial infection (NI) in the Respiratory Intensive Care Unit (RICU) of a teaching hospital in Northwest China. Methods An observational, prospective surveillance was conducted in the RICU from 2013 to 2015. The overall infection rate, distribution of infection sites, device-associated infections and pathogen in the RICU were investigated. Then, the logistic regression analysis was used to test the risk factors for RICU infection. Results In this study, 102 out of 1347 patients experienced NI. Among them, 87 were device-associated infection. The overall prevalence of NI was 7.57% with varied rates from 7.19 to 7.73% over the 3 years. The lower respiratory tract (43.1%), urinary tract (26.5%) and bloodstream (20.6%) infections accounted for the majority of infections. The device-associated infection rates of urinary catheter, central catheter and ventilator were 9.8, 7.4 and 7.4 per 1000 days, respectively.The most frequently isolated pathogens were Staphylococcus aureus (20.9%), Klebsiella pneumoniae (16.4%) and Pseudomonas aeruginosa (10.7%). Multivariate analysis showed that the categories D or E of Average Severity of Illness Score (ASIS), length of stay (10–30, 30–60, ≥60 days), immunosuppressive therapy and ventilator use are the independent risk factors for RICU infection with an adjusted odds ratio (OR) of 1.65 (95% CI: 1.15~2.37), 5.22 (95% CI: 2.63~10.38)), 2.32 (95% CI: 1.19~4.65), 8.93 (95% CI: 3.17~21.23), 31.25 (95% CI: 11.80~63.65)) and 2.70 (95% CI: 1.33~5.35), respectively. Conclusion A relatively low and stable rate of NI was observed in our RICU through year 2013–2015. The ASIS-D、E, stay ≥10 days, immunosuppressive therapy and ventilator use are the independent risk factors for RICU infection.…

Abstract Background The etiology and epidemiology of acute otitis media (AOM) are poorly understood in China. This study aimed to describe the etiology of AOM and the phenotypic and molecular characteristics of AOM-causing Streptococcus pneumoniae (S.pneumoniae) recovered from Chinese children. Methods A retrospective study was conducted to enrol patients younger than 18 years diagnosed as AOM. Middle ear fluid specimens were collected then cultured for bacterial pathogens. All S.pneumoniae isolates were tested for antibiotic susceptibility, serotypes, virulence genes, antibiotic resistant determinants and sequence types. Results The dominant otopathogen among AOM children was S.pneumoniae (54.4%). Among S.pneumoniae isolates, there were 97.3, 97.3 and 75.7% isolates resistant to erythromycin, tetracycline and trimethoprim-sulfamethoxazole, respectively. There was 72.8% S.pneumoniae with multidrug resistance. The dominant sequence types (STs) were ST271 and ST320, whereas the prevailing serotypes were 19F and 19A. The 7-valent and 13-valent pneumococcal conjugate vaccine (PCV) coverage among AOM children were 73.0 and 94.6%, respectively. Additionally, we found that CC271 expressed more of mef(A/E) (P 

Sergio Carrasco-Anabalón, Carlos Orlando Conceição Neto, Ana Paula D’Alincourt Carvalho-Assef, Celia A. Lima, Marcela Cifuentes, Francisco Silva, Boris Barrera, Mariana Domínguez, Gerardo González-Rocha, Helia Bello-Toledo

Laura P. Hale, Gowrisankar Rajam, George M. Carlone, Chen Jiang, Kouros Owzar, Greg Dugan, David Caudell, Nelson Chao, J. Mark Cline, Thomas C. Register, Gregory D. Sempowski

by Laura P. Hale, Gowrisankar Rajam, George M. Carlone, Chen Jiang, Kouros Owzar, Greg Dugan, David Caudell, Nelson Chao, J. Mark Cline, Thomas C. Register, Gregory D. Sempowski While exposure to radiation can be lifesaving in certain settings, it can also potentially result in long-lasting adverse effects, particularly to hematopoietic and immune cells. This study investigated hematopoietic recovery and immune function in rhesus macaques Cross-sectionally (at a single time point) 2 to 5 years after exposure to a single large dose (6.5 to 8.4 Gray) of total body radiation (TBI) derived from linear accelerator-derived photons (2 MeV, 80 cGy/minute) or Cobalt 60-derived gamma irradiation (60 cGy/min). Hematopoietic recovery was assessed through measurement of complete blood counts, lymphocyte subpopulation analysis, and thymus function assessment. Capacity to mount specific antibody responses against rabies, Streptococcus pneumoniae, and tetanus antigens was determined 2 years after TBI. Irradiated macaques showed increased white blood cells, decreased platelets, and decreased frequencies of peripheral blood T cells. Effects of prior radiation on production and export of new T cells by the thymus was dependent on age at the time of analysis, with evidence of interaction with radiation dose for CD8+ T cells. Irradiated and control animals mounted similar mean antibody responses to proteins from tetanus and rabies and to 10 of 11 serotype-specific pneumococcal polysaccharides. However, irradiated animals uniformly failed to make antibodies against polysaccharides from serotype 5 pneumococci, in contrast to the robust responses of non-irradiated controls. Trends toward decreased serum levels of anti-tetanus IgM and slower peak antibody responses to rabies were also observed. Taken together, these data show that dose-related changes in peripheral blood cells and immune responses to both novel and recall antigens can be detected 2 to 5 years after exposure to whole body radiation. Longer term follow-up data on this cohort and independent validation will be helpful to determine whether these changes persist or whether additional changes become evident with increasing time since radiation, particularly as animals begin to develop aging-related changes in immune function.

Abstract Background To evaluate the in vitro activities of plazomicin and comparator aminoglycosides and elucidate the underlying aminoglycoside resistance mechanisms among carbapenemase-producing K. pneumoniae isolates collected during a nationwide surveillance study in Greek hospitals. Methods Three hundred single-patient carbapenemase-producing K. pneumoniae isolates were studied, including 200 KPC-, 50 NDM-, 21 VIM-, 14 KPC & VIM-, 12 OXA-48-, two NDM & OXA- and one KPC & OXA-producing isolates. Susceptibility testing was performed by broth microdilution, and minimum inhibitory concentrations (MICs) interpreted per EUCAST breakpoints. Carbapenemase-, aminoglycoside modifying enzyme- and 16S rRNA methylase- encoding genes were detected by PCR. Results Of 300 isolates tested, 5.7% were pandrug resistant and 29.3% extensively drug resistant. Plazomicin inhibited 87.0% of the isolates at ≤2 mg/L, with MIC50/MIC90 of 0.5/4 mg/L. Apramycin (a veterinary aminoglycoside) inhibited 86.7% of the isolates at ≤8 mg/L and was the second most active drug after plazomicin, followed by gentamicin (S, 43%; MIC50/MIC90, 4/> 256) and amikacin (S, 18.0%; MIC50/MIC90, 32/128). Twenty-three (7.7%) isolates (16 KPC-, 6 VIM- and one KPC & OXA-48-producers) exhibited MICs ≥64 mg/L for plazomicin, and harbored rmtB (n = 22) or armA (n = 1). AAC(6′)-Іb was the most common aminoglycoside modifying enzyme (84.7%), followed by AAC(3΄)-IIa (25.3%), while those two enzymes were co-produced by 21.4% of the isolates. Conclusions Plazomicin retains activity against most carbapenemase-producing K. pneumoniae isolated from Greek hospitals, with MICs consistently lower than those of the other aminoglycosides, even in the presence of aminoglycoside modifying enzymes. Dissemination of 16S- rRNA methylases in 8% of the isolates is an unwelcome event that needs strict infection control measures and rigorous stewardship interventions.…

Community-acquired pneumonia is the most common infection leading to hospitalization and death in all age groups, especially the elderly. The economic effect is substantial, with annual costs in excess of $17 billion in the United States and €10 billion in Europe. For pathogens such as……

Abstract Background Emerging antimicrobial resistance is a significant threat to human health. However, methods for rapidly diagnosing antimicrobial resistance generally require multi-day culture-based assays. Macrolide efflux gene A, mef(A), provides resistance against erythromycin and azithromycin and is known to be laterally transferred among a wide range of bacterial species. Methods We use Recombinase Polymerase Assay (RPA) to detect the antimicrobial resistance gene mef(A) from raw lysates without nucleic acid purification. To validate these results we performed broth dilution assays to assess antimicrobial resistance to erythromycin and ampicillin (a negative control). Results We validate the detection of mef(A) in raw lysates of Streptococcus pyogenes, S. pneumoniae, S. salivarius, and Enterococcus faecium bacterial lysates within 7–10 min of assay time. We show that detection of mef(A) accurately predicts real antimicrobial resistance assessed by traditional culture methods, and that the assay is robust to high levels of spiked-in non-specific nucleic acid contaminant. The assay was unaffected by single-nucleotide polymorphisms within divergent mef(A) gene sequences, strengthening its utility as a robust diagnostic tool. Conclusions This finding opens the door to implementation of rapid genomic diagnostics in a clinical setting, while providing researchers a rapid, cost-effective tool to track antibiotic resistance in both pathogens and commensal strains.…

Vaughn V, Gandhi T, Conlon A, et al.

AbstractBackgroundFluoroquinolones increase the risk of Clostridioides difficile infection and antibiotic resistance. Hospitals often use pre-prescription approval or prospective audit and feedback to target fluoroquinolone prescribing. Whether these strategies impact aggregate fluoroquinolone use is unknown.MethodsThis study is a 48-hospital, retrospective cohort of general-care, medical patients hospitalized with pneumonia or positive urine culture between December 2015–September 2017. Hospitals were surveyed on their use of pre-prescription approval and/or prospective audit and feedback to target fluoroquinolone prescribing during hospitalization (fluoroquinolone stewardship). After controlling for hospital clustering and patient factors, aggregate (inpatient and post-discharge) fluoroquinolone (ciprofloxacin, levofloxacin, moxifloxacin) exposure was compared between hospitals with and without fluoroquinolone stewardship.ResultsThere were 11 748 patients (6820 pneumonia; 4928 positive urine culture) included at 48 hospitals. All hospitals responded to the survey: 29.2% (14/48) reported using pre-prescription approval and/or prospective audit and feedback to target fluoroquinolone prescribing. After adjustment, fluoroquinolone stewardship was associated with fewer patients receiving a fluoroquinolone (37.1% vs 48.2%; P = .01) and fewer fluoroquinolone treatment days per 1000 patients (2282 vs 3096 days/1000 patients; P = .01), driven by lower inpatient prescribing. However, most (66.6%) fluoroquinolone treatment days occurred after discharge, and hospitals with fluoroquinolone stewardship had twice as many new fluoroquinolone starts after discharge as hospitals without (15.6% vs 8.4%; P = .003).ConclusionsHospital-based stewardship interventions targeting fluoroquinolone prescribing were associated with less fluoroquinolone prescribing during hospitalization, but not at discharge. To limit aggregate fluoroquinolone exposure, stewardship programs should target both inpatient and discharge prescribing.

Paola Bocanegra-Ibarias, Elvira Garza-González, Magaly Padilla-Orozco, Soraya Mendoza-Olazarán, Eduardo Pérez-Alba, Samantha Flores-Treviño, Ulises Garza-Ramos, Jesus Silva-Sánchez, Adrián Camacho-Ortiz

by Paola Bocanegra-Ibarias, Elvira Garza-González, Magaly Padilla-Orozco, Soraya Mendoza-Olazarán, Eduardo Pérez-Alba, Samantha Flores-Treviño, Ulises Garza-Ramos, Jesus Silva-Sánchez, Adrián Camacho-Ortiz The worldwide dissemination of high-risk carbapenemase-producing Klebsiella pneumoniae clones has become a major threat to healthcare facilities. This study describes the successful containment of a hospital outbreak caused by NDM-1-producing K. pneumoniae Sequence Type (ST) 307 using active surveillance. The outbreak began when a patient was transferred from a local hospital. After 48 hours in our hospital, a tracheal aspirate was positive for a meropenem resistant and carbapenemase-producing K. pneumoniae. All patients in the medical intensive care unit (ICU) and the neurology wards were subject to contact precautions. The hospital surfaces and devices, healthcare workers, and patients from these wards were screened by cultures. Fecal swabs were placed into broth and PCR for blaKPC, blaOXA-48, blaIMP, blaVIM, and blaNDM, which were performed directly from the broth after 12 hours. PCRs were also performed on DNA extracted from carbapenemase-producing species from subcultured broths. Five and nine days later, two more patients’ rectal swabs tested positive. Molecular assays identified K. pneumoniae blaNDM-1 onto a 130-kb conjugative plasmid (IncY, IncFIIs, and IncFIIY), ST307. After the three patients were discharged, monitoring continued, and after three weeks with negative results, rectal swabbing ended. In conclusion, it was possible to contain a hospital outbreak caused by NDM-1-producing K. pneumoniae ST307 through epidemiological and microbiological surveillance. With the methodology used, the detection of NDM-type genes in fecal samples was obtained in approximately 15 hours after obtaining the fecal sample.

Abstract Background The prognostic capability of the quick Sequential Organ Failure Assessment (qSOFA) bedside scoring tool is uncertain in non-ICU patients with sepsis due to bacteremia given the low number of patients previously evaluated. Methods We performed a retrospective cohort study of adult hospitalized patients with Staphylococcus aureus bacteremia (SAB). Medical charts were reviewed to determine qSOFA score, systemic inflammatory response syndrome (SIRS) criteria, and Pitt bacteremia score (PBS) at initial presentation; their predictive values were compared for ICU admission within 48 h, ICU stay duration > 72 h, and 30-day mortality. Results Four hundred twenty-two patients were included; 22% had qSOFA score ≥2. Overall, mean age was 56y and 75% were male. More patients with qSOFA ≥2 had altered mentation (23% vs 5%, p