Evangelos Papadomichelakis

An Outbreak of Infection due to β-Lactamase Klebsiella pneumoniae Carbapenemase 2–Producing K. pneumoniae in a Greek University Hospital: Molecular Characterization, Epidemiology, and Outcomes

BACKGROUND We describe the emergence and spread of Klebsiella pneumoniae carbapenemase 2 (KPC-2)-producing K. pneumoniae at a Greek University hospital. METHODS Isolates with a carbapenem minimum inhibitory concentration >1 microg/mL and a negative EDTA-imipenem disk synergy test result were submitted to boronic acid disk test and to polymerase chain reaction (PCR) for KPC gene and sequencing. Records from patients who had KPC-2-producing K. pneumoniae isolated were retrospectively reviewed. Clinical isolates were submitted to molecular typing using pulsed-field gel electrophoresis, and the beta-lactamase content was studied using isoelectric focusing and PCR. RESULTS From January 2007 through December 2008, 50 patients (34 in the intensive care unit [ICU]) were colonized (n = 32) or infected (n = 18) by KPC-2-producing K. pneumoniae. Increasing prevalence of KPC-2-producing K. pneumoniae coincided with decreasing prevalence of metallo-beta lactamase-producing isolates in our ICU. Multidrug resistance characterized the studied isolates, with colistin, gentamicin, and fosfomycin being the most active agents. Besides KPC-2, clinical isolates encoded TEM-1-like, SHV-11, SHV-12, CTX-M-15, and LEN-19 enzymes. Four different clonal types were detected; the predominant one comprised 41 single patient isolates (82%). Sporadic multiclonal cases of KPC-2-producing K. pneumoniae infection were identified from September 2007 through May 2008. The outbreak strain was introduced in February 2008 and disseminated rapidly by cross-transmission; 38 patients (76%) were identified after August 2008. Fourteen cases of bacteremia, 2 surgical site infections, 2 lower respiratory tract infections (1 bacteremic), and 1 urinary tract infection were identified. Most patients received a colistin-containing combination treatment. Crude mortality was 58.8% among ICU patients and 37.5% among non-ICU patients, but attributable mortality was 22.2% and 33.3%, respectively. CONCLUSIONS The emergence of KPC-2-producing K. pneumoniae in Greek hospitals creates an important challenge for clinicians and hospital epidemiologists, because it is added to the already high burden of antimicrobial resistance.

Effect of Clarithromycin in Patients with Sepsis and Ventilator-Associated Pneumonia

BACKGROUND Because clarithromycin provided beneficiary nonantibiotic effects in experimental studies, its efficacy was tested in patients with sepsis and ventilator-associated pneumonia (VAP). METHODS Two hundred patients with sepsis and VAP were enrolled in a double-blind, randomized, multicenter trial from June 2004 until November 2005. Clarithromycin (1 g) was administered intravenously once daily for 3 consecutive days in 100 patients; another 100 patients were treated with placebo. Main outcomes were resolution of VAP, duration of mechanical ventilation, and sepsis-related mortality within 28 days. RESULTS The groups were well matched with regard to demographic characteristics, disease severity, pathogens, and adequacy of the administered antimicrobials. Analysis comprising 141 patients who survived revealed that the median time for resolution of VAP was 15.5 days and 10.0 days among placebo- and clarithromycin-treated patients, respectively (P = .011); median times for weaning from mechanical ventilation were 22.5 days and 16.0 days, respectively (p = .049). Analysis comprising all enrolled patients showed a more rapid decrease of the clinical pulmonary infection score and a delay for advent of multiple organ dysfunction in clarithromycin-treated patients, compared with those of placebo-treated patients (p = .047). Among the 45 patients who died of sepsis, time to death was significantly prolonged in clarithromycin-treated compared with placebo-treated patients (p = .004). Serious adverse events were observed in 0% and 3% of placebo- and clarithromycin-treated patients, respectively (P = .25). CONCLUSIONS Clarithromycin accelerated the resolution of VAP and weaning from mechanical ventilation in surviving patients and delayed death in those who died of sepsis. The mortality rate at day 28 was not altered. Results are encouraging and render new perspectives on the management of sepsis and VAP.

Colonization and infection by colistin-resistant Gram-negative bacteria in a cohort of critically ill patients.

In recent years there has been renewed interest in colistin for the treatment of infections by multidrug-resistant Gram-negative bacteria, causing concern that increasing use may be accompanied by the emergence of resistance. This is a retrospective cohort study of colonization and infection by colistin-resistant (CR) gram-negative bacteria in critically ill patients. Colonization data were based on surveillance culture results. Among 150 patients, 78 (52%) were colonized by CR Gram-negative bacteria. Among them, 30 (20%) were colonized by Klebsiella pneumoniae isolates and 51 (34%) were colonized by intrinsically resistant to colistin (CIR) enterobacteriaceae. Seven cases of infection were caused by CR K. pneumoniae and 12 cases by CIR strains. The main risk factor for colonization by CR pathogens was colistin treatment.

Linezolid use associated with lactic acidosis

Linezolid is a new synthetic antibiotic with a broad spectrum of activity against virtually all important Gram-positive infections. Lactic acidosis is a well known side-effect of metformin and nucleoside reverse-transcriptase inhibitors. We report a case in which lactic acidosis developed as an adverse effect of linezolid treatment.

Prognostic importance of increased plasma amino-terminal pro-brain natriuretic peptide levels in a large noncardiac, general intensive care unit population.

The present study aimed to determine whether amino-terminal pro-brain natriuretic peptide (NT-pro-BNP) predicts intensive care unit (ICU) mortality in a cohort of general, noncardiac, critically ill patients. To this end, a total of 233 consecutive mechanically ventilated patients (109 men) having a median age of 60 years and a wide range in admitting diagnoses, including medical (n = 118), surgical (n = 83), and multiple trauma (n = 32) cases were prospectively studied. Median Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment scores on ICU admission were 16 and 9, respectively. The study end point was ICU outcome. Blood samples were drawn on admission in the ICU and on postadmission days 1 and 2 to determine NT-pro-BNP levels. In a subgroup (n = 77), admission proinflammatory and anti-inflammatory cytokine levels, including TNF-&agr;, IL-6, and IL-10, were also measured. Nonsurvivors (n = 98) had significantly higher NT-pro-BNP levels than survivors (n = 135) on admission in the ICU (2,074 vs. 283 pg/mL; P < 0.001), on day 1 (2,197 vs. 221 pg/mL; P < 0.001), and on day 2 (2,726 vs. 139 pg/mL; P < 0.001). Median values for TNF-&agr;, IL-6, and IL-10 were 3.70, 131.57, and 111.88 pg/mL, respectively. Receiver operating characteristic analysis showed that the area under the receiver operating characteristic curve in predicting ICU mortality was 0.70 for APACHE II and 0.77 for admission NT-pro-BNP (P = 0.08). The cutoff in admission NT-pro-BNP that best predicted outcome was 941 pg/mL. Multiple logistic regression analysis revealed that APACHE II score (odds ratio, 1.06; P = 0.007) and the best cutoff point in admission NT-pro-BNP (odds ratio, 7.74; P < 0.001) independently predicted ICU mortality, even if cytokines were entered in the analysis. In conclusion, plasma NT-pro-BNP is frequently raised in noncardiac, mixed, critically ill patients, and nonsurvivors have consistently higher levels than survivors. Elevated admission NT-pro-BNP represents an independent predictor for poor ICU outcome in the presence of clinical severity scores.

Effect of clarithromycin in patients with suspected Gram-negative sepsis: results of a randomized controlled trial

BACKGROUND A previous randomized study showed that clarithromycin decreases the risk of death due to ventilator-associated pneumonia and shortens the time until infection resolution. The efficacy of clarithromycin was tested in a larger population with sepsis. METHODS Six hundred patients with systemic inflammatory response syndrome due to acute pyelonephritis, acute intra-abdominal infections or primary Gram-negative bacteraemia were enrolled in a double-blind, randomized, multicentre trial. Clarithromycin (1 g) was administered intravenously once daily for 4 days consecutively in 302 patients; another 298 patients were treated with placebo. Mortality was the primary outcome; resolution of infection and hospitalization costs were the secondary outcomes. RESULTS The groups were well matched for demographics, disease severity, microbiology and appropriateness of the administered antimicrobials. Overall 28 day mortality was 17.1% (51 deaths) in the placebo arm and 18.5% (56 deaths) in the clarithromycin arm (P = 0.671). Nineteen out of 26 placebo-treated patients with septic shock and multiple organ dysfunctions died (73.1%) compared with 15 out of 28 clarithromycin-treated patients (53.6%, P = 0.020). The median time until resolution of infection was 5 days in both arms. In the subgroup with severe sepsis/shock, this was 10 days in the placebo arm and 6 days in the clarithromycin arm (P = 0.037). The cost of hospitalization was lower after treatment with clarithromycin (P = 0.044). Serious adverse events were observed in 1.3% and 0.7% of placebo- and clarithromycin-treated patients, respectively (P = 0.502). CONCLUSIONS Intravenous clarithromycin did not affect overall mortality; however, administration shortened the time to resolution of infection and decreased the hospitalization costs.

Exhaled Breath Condensate in Mechanically Ventilated Brain-injured Patients with No Lung Injury or Sepsis

BACKGROUND The inflammatory influence of prolonged mechanical ventilation in uninjured lungs remains a matter of controversy and largely unexplored in humans. The authors investigated pulmonary inflammation by using exhaled breath condensate (EBC) in mechanically ventilated, brain-injured patients in the absence of acute lung injury or sepsis and explored the potential influence of positive end-expiratory pressure (PEEP). METHODS Inflammatory EBC markers were assessed in 27 mechanically ventilated, brain-injured patients with neither acute lung injury nor sepsis and in 12 healthy and 8 brain-injured control subjects. Patients were ventilated with 8 ml/kg during zero end-expiratory pressure (ZEEP group, n = 12) or 8 cm H(2)O PEEP (PEEP group, n = 15). EBC was collected on days 1, 3, and 5 of mechanical ventilation to measure pH; interleukins (IL)-10, 1β, 6, 8, and 12p70; and tumor necrosis factor-α. RESULTS EBC pH was lower, whereas IL-1β and tumor necrosis factor-α were greater in both patient groups compared with either control group; IL-6 was higher, whereas IL-10 and IL-12p70 were sporadically higher than in healthy control subjects; no differences were noted between the two patient groups, except for IL-10, which decreased by day 5 during PEEP. Leukocytes, soluble IL-6, and soluble triggering receptor expressed on myeloid cells-1 in blood were constantly higher during zero end-expiratory pressure; EBC cytokines appeared mostly related to soluble IL-8 and inversely related to soluble triggering receptor expressed on myeloid cells-1. CONCLUSIONS In brain-injured, mechanically ventilated patients with neither acute lung injury nor sepsis, EBC markers appear to indicate the presence of subtle pulmonary inflammation that is mostly unaffected by PEEP. There is evidence for a systemic inflammatory response, especially in patients during zero end-expiratory pressure.

The functional role of natural killer cells early in clinical sepsis

Although much information is available for the function of circulating monocytes when signs of sepsis are apparent, little is known for natural killer (NK) cells. NK cells were isolated from 10 healthy controls and from 103 patients with sepsis within the first 24 h from diagnosis. NK cells were stimulated with lipopolysaccharide for cytokine production. Release of tumor necrosis factor‐alpha and of interleukin (IL)‐6 was below the limit of detection. Release of IL‐23 and of interferon‐gamma (IFNγ) was significantly greater among patients than among healthy volunteers. Release of IFNγ was pronounced in septic shock. Patients were divided into two subgroups based on the ratio of IFNγ to IL‐23 released by the NK cells after stimulation: those with ratio ≤5 and 28‐day survival 13.5%, and those with ratio >5 and 28‐day survival 29.4% (p: 0.048). It is concluded that early after clinical development of sepsis, NK cells remain active for the production of IFNγ. Their activity is associated with the final outcome.

Reduction of Environmental Contamination With Multidrug-Resistant Bacteria by Copper-Alloy Coating of Surfaces in a Highly Endemic Setting

OBJECTIVE To evaluate the efficacy of copper-coating in reducing environmental colonization in an intensive-care unit (ICU) with multidrug-resistant-organism (MDRO) endemicity DESIGN Interventional, comparative crossover trial SETTING The general ICU of Attikon University hospital in Athens, Greece PATIENTS Those admitted to ICU compartments A and B during the study period METHODS Before any intervention (phase 1), the optimum sampling method using 2 nylon swabs was validated. In phase 2, 6 copper-coated beds (ie, with coated upper, lower, and side rails) and accessories (ie, coated side table, intravenous [i.v.] pole stands, side-cart handles, and manual antiseptic dispenser cover) were introduced as follows: During phase 2a (September 2011 to February 2012), coated items were placed next to noncoated ones (controls) in both compartments A and B; during phase 2b (May 2012 to January 2013), all copper-coated items were placed in compartment A, and all noncoated ones (controls) in compartment B. Patients were randomly assigned to available beds. Environmental samples were cultured quantitatively for clinically important bacteria. Clinical and demographic data were collected from medical records. RESULTS Copper coating significantly reduced the percentage of colonized surfaces (55.6% vs 72.5%; P<.0001), the percentage of surfaces colonized by MDR gram-negative bacteria (13.8% vs 22.7%; P=.003) or by enterococci (4% vs 17%; P=.014), the total bioburden (2,858 vs 7,631 cfu/100 cm2; P=.008), and the bioburden of gram-negative isolates, specifically (261 vs 1,266 cfu/100 cm2; P=.049). This effect was more pronounced when the ratio of coated surfaces around the patient was increased (phase 2b). CONCLUSIONS Copper-coated items in an ICU setting with endemic high antimicrobial resistance reduced environmental colonization by MDROs. Infect Control Hosp Epidemiol 2017;38:765-771.

Clarithromycin Leads to Long-Term Survival and Cost Benefit in Ventilator-Associated Pneumonia and Sepsis

ABSTRACT Increasing numbers of admissions for sepsis impose a heavy burden on health care systems worldwide, while novel therapies have proven both expensive and ineffective. We explored the long-term mortality and hospitalization costs after adjunctive therapy with intravenous clarithromycin in ventilator-associated pneumonia (VAP). Two hundred patients with sepsis and VAP were enrolled in a published randomized clinical trial; 100 were allocated to blind treatment with a placebo and another 100 to clarithromycin at 1 g daily for three consecutive days. Long-term mortality was recorded. The hospitalization cost was calculated by direct quantitation of imaging tests, medical interventions, laboratory tests, nonantibiotic drugs and antibiotics, intravenous fluids, and parenteral and enteral nutrition. Quantities were priced by the respective prices defined by the Greek government in 2002. The primary endpoint was 90-day mortality; cumulative hospitalization cost was the secondary endpoint. All-cause mortality rates on day 90 were 60% in the placebo arm and 43% in the clarithromycin arm (P = 0.023); 141 patients were alive on day 28, and mortality rates between days 29 and 90 were 44.4% and 17.4%, respectively (P = 0.001). The mean cumulative costs on day 25 in the placebo group and in the clarithromycin group were €14,701.10 and €13,100.50 per patient staying alive, respectively (P = 0.048). Respective values on day 45 were €26,249.50 and €19,303.10 per patient staying alive (P = 0.011); this was associated with the savings from drugs other than antimicrobials. It is concluded that intravenous clarithromycin for three consecutive days as an adjunctive treatment in VAP and sepsis offers long-term survival benefit along with a considerable reduction in the hospitalization cost. (This study has been registered at ClinicalTrials.gov under registration no. NCT00297674.)