Lisa Saidel-Odes

Attributable Mortality Rate for Carbapenem-Resistant Klebsiella pneumoniae Bacteremia

OBJECTIVE To determine the attributable (direct) mortality and morbidity caused by carbapenem-resistant Klebsiella pneumoniae bacteremia. DESIGN A matched retrospective, historical cohort design, using a stepwise procedure to stringently match the best control subjects to the best case subjects. SETTING A 1,000-bed tertiary-care university teaching hospital. PATIENTS Case subjects were defined as adult patients with carbapenem-resistant K. pneumoniae bacteremia during the period from October 2005 through October 2008. Control subjects were defined as patients who were very similar to case subjects except that they did not have bacteremia. METHODS Matching potential control subjects to case subjects was performed at a 1:1 ratio using a computerized record system. The criteria used included same hospitalization period, similar Charlson comorbidity index, same underlying disease, same age within 10 years, and same sex. Demographic and clinical characteristics were collected from medical records. RESULTS During the study period, 319 patients developed an infection due to carbapenem-resistant K. pneumoniae. Of these 319 patients, 39 (12.2%) developed a bloodstream infection, for an overall rate of 0.59 episodes of carbapenem-resistant K. pneumoniae bacteremia per 10,000 patient-days. We excluded 7 patients from our study, leaving a total of 32 case subjects in our cohort. Case subjects were significantly more likely than control subjects (n = 32) to require care in an intensive care unit (12 case subjects [37.5%] vs 3 control subjects [9.4%]), ventilator support (17 case subjects [53.1%] vs 8 control subjects [25%]), and use of a central venous catheter (19 case subjects [59.4%] vs 9 control subjects [28.1%]). For case subjects, the crude mortality rate was 71.9% (ie, 23 of the 32 case subjects died); for control subjects, the crude mortality rate was 21.9% (ie, 7 of the 32 control subjects died) (P < .001. For case subjects, the attributable mortality was 50% (95% confidence interval [CI], 15.3%-98.6%). A mortality risk ratio of 3.3 (95% CI, 2.9-28.5) was found for case subjects with carbapenem-resistant K. pneumoniae bacteremia. CONCLUSIONS Patients with carbapenem-resistant K. pneumoniae require more intensive and invasive care. We have shown that the crude and attributable mortality rates associated with carbapenem-resistant K. pneumoniae bacteremia were striking.

A Randomized, Double-Blind, Placebo-Controlled Trial of Selective Digestive Decontamination Using Oral Gentamicin and Oral Polymyxin E for Eradication of Carbapenem-Resistant Klebsiella pneumoniae Carriage

OBJECTIVE To assess the effectiveness of selective digestive decontamination (SDD) for eradicating carbapenem-resistant Klebsiella pneumoniae (CRKP) oropharyngeal and gastrointestinal carriage. DESIGN A randomized, double-blind, placebo-controlled trial with 7 weeks of follow-up per patient. SETTING A 1,000-bed tertiary-care university hospital. PATIENTS Adults with CRKP-positive rectal swab cultures. METHODS Patients were blindly randomized (1 :1) over a 20-month period. The SDD arm received oral gentamicin and polymyxin E gel (0.5 g 4 times per day) and oral solutions of gentamicin (80 mg 4 times per day) and polymyxin E (1 x 10(6) units 4 times per day for 7 days). The placebo arm received oral placebo gel 4 times per day and 2 placebo oral solutions 4 times per day for 7 days. Strict contact precautions were applied. Samples obtained from the throat, groin, and urine were also cultured. RESULTS Forty patients (mean age ± standard deviation, 71 ± 16 years; 65% male) were included. At screening, greater than or equal to 30% of oropharyngeal, greater than or equal to 60% of skin, and greater than or equal to 35% of urine cultures yielded CRKP isolates. All throat cultures became negative in the SDD arm after 3 days (P < .0001). The percentages of rectal cultures that were positive for CRKP were significantly reduced at 2 weeks. At that time, 16.1% of rectal cultures in the placebo arm and 61.1% in the SDD arm were negative (odds ratio, 0.13; 95% confidence interval, 0.02-0.74; P < .0016). A difference between the percentages in the 2 arms was still maintained at 6 weeks (33.3% vs 58.5%). Groin colonization prevalence did not change in either arm, and the prevalence of urine colonization increased in the placebo arm. CONCLUSIONS This SDD regimen could be a suitable decolonization therapy for selected patients colonized with CRKP, such as transplant recipients or immunocompromised patients pending chemotherapy and patients who require major intestinal or oropharyngeal surgery. Moreover, in outbreaks caused by CRKP infections that are uncontrolled by routine infection control measures, SDD could provide additional infection containment.

Risk factors for developing clinical infection with carbapenem-resistant Klebsiella pneumoniae in hospital patients initially only colonized with carbapenem-resistant K pneumoniae.

BACKGROUND This study examined predictors of carbapenem-resistant Klebsiella pneumoniae (CRKP) colonization and risk factors for the development of CRKP infection in patients initially only colonized with CRKP. METHODS A total of 464 patients with CRKP rectal colonization (CRKP-RC) were identified. Two case-control studies were performed, one comparing risk factors for CRKP-RC in patients who did not develop CRKP infection (CRKP-IN) versus patients without CRKP-RC and CRKP-IN, and the other comparing CRKP-RC patients who did not develop CRKP-IN with those who did. RESULTS Forty-two of the 464 colonized patients developed CRKP-IN. Multivariate analysis identified the following predictors for CRKP-RC: antibiotic therapy (odds ratio [OR], 5.76; P ≤ .0001), aminopenicillin therapy (OR, 7.753; P = .004), bedridden (OR, 3.09; P = .021), and nursing home residency (OR, 3.09; P = .013). Risk factors for CRKP-IN in initially CRKP-RC-positive patients were previous invasive procedure (OR, 5.737; P = .021), diabetes mellitus (OR, 4.362; P = .017), solid tumor (OR, 3.422; P = .025), tracheostomy (OR, 4.978; P = .042), urinary catheter insertion (OR, 4.696; P = .037), and antipseudomonal penicillin (OR, 23.09; P ≤ .0001). CONCLUSIONS We suggest that in patients with CRKP-RC, a strategy for preventing CRKP-IN might include limiting antipseudomonal penicillin and carbapenem use and preventing infections by closely following compliance with infection control bundles.

A Multifaceted Intervention Strategy for Eradication of a Hospital-Wide Outbreak Caused by Carbapenem-Resistant Klebsiella pneumoniae in Southern Israel

OBJECTIVE To devise a local strategy for eradication of a hospital-wide outbreak caused by carbapenem-resistant Klebsiella pneumoniae (CRKP). DESIGN Quasi-experimental, before-and-after, interrupted time-series study. SETTING A 1,000-bed tertiary-care university teaching hospital. METHODS Retrospectively, all relevant data were collected from the medical records of patients with CRKP infections from May 2006 through April 2007, the preintervention period. From May 1, 2007, through May 1, 2010, the postintervention period, the intervention was applied and prospectively followed. The 5 key elements of this strategy were an emergency department flagging system, the building of a cohort ward, the eradication of clusters, environmental and personnel hand cultures, and a carbapenem-restriction policy. The demographic and clinical parameters of patients colonized by and/or infected with CRKP were collected from medical records. RESULTS A total of 10,680 rectal cultures were performed for 8,376 patients; 433 (5.16%) and 370 (4.4%) were CRKP-colonized and CRKP-infected patients, respectively, and 789 (98%) of 803 patients were admitted to the CRKP cohort ward. The CRKP infection density was reduced from 5.26 to 0.18 per 10,000 patient-days (P ≤ .001), and no nosocomial CRKP infections were diagnosed. Twenty-three percent of environmental cultures were found to be positive. Meropenem use was reduced from 283 ± 70.92 to 118 ± 74.32 defined daily doses per 1,000 patient-days (P ≤ .001). CONCLUSION This intervention produced an enormous impact on patient location, surveillance cultures, and antibiotic policies and a massive investment in infection control resources.

Limiting and controlling carbapenem-resistant Klebsiella pneumoniae.

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is resistant to almost all antimicrobial agents, is associated with substantial morbidity and mortality, and poses a serious threat to public health. The ongoing worldwide spread of this pathogen emphasizes the need for immediate intervention. This article reviews the global spread and risk factors for CRKP colonization/infection, and provides an overview of the strategy to combat CRKP dissemination.

Bloodstream infections caused by multi-drug resistant Proteus mirabilis: Epidemiology, risk factors and impact of multi-drug resistance

ABSTRACT Background The prevalence of antimicrobial co-resistance among ESBL-producing Enterobactereaceae is extremely high in Israel. Multidrug-resistant Proteus mirabilis strains (MDR-PM), resistant to almost all antibiotic classes have been described. The aim was to determine the risk factors for bloodstream infections caused by MDR-PM and clinical outcomes. Methods A retrospective case-control study. Adult patients with PM bacteremia during 7 years were identified retrospectively and their files reviewed for demographics, underlying diseases, Charlson Comorbidity Index, treatment and outcome. Results One hundred and eighty patients with PM-bloodstream infection (BSI) were included; 90 cases with MDR-PM and 90 controls with sensitive PM (S-PM). Compared to controls, cases more frequently were from nursing homes, had recurrent hospital admissions in the past year and received antibiotic therapy in the previous 3 months, were bedridden and suffered from peripheral vascular disease and peptic ulcer disease (p < 0.001). Two-thirds of the MDR-PM isolates were ESBL-producers vs 4.4% of S-PM isolates (p < 0.001, OR = 47.6, 95% CI = 15.9–142.6). In-hospital crude mortality rate of patients with MDR-PM BSI was 37.7% vs 23.3% in those with S-PM BSI (p = 0.0359, OR = 2, 95% CI = 1.4–3.81). Conclusions PM bacteremia in elderly and functionally-dependent patients is likely to be caused by nearly pan-resistant PM strains in the institution; 51.8% of the patients received inappropriate empiric antibiotic treatment. The crude mortality rate of patients with MDR-PM BSI was significantly higher than that of patients with S-PM BSI.

An outbreak of varicella in staff nurses exposed to a patient with localized herpes zoster

Abstract An outbreak of varicella occurred in an internal medicine ward. The outbreak comprised 3 nurses, 2 of whom were directly exposed to an immunocompetent patient with localized herpes zoster. Our observation provides an argument for airborne precautions in hospitalized patients with localized herpes zoster.

Epidemiological and clinical characteristics of methicillin sensitive Staphylococcus aureus (MSSA) bacteriuria

OBJECTIVES To determine the frequency of MSSA bacteriuria in our hospital, ascertain nosocomial and community-acquired risk factors, identify specific epidemiological characteristics among bacteriuric patients with/without MSSA bacteremia. METHODS Adult patients with MSSA bacteriuria during 44 months identified retrospectively; their files reviewed for demographics, Charlson Comorbidity Index, urinary tract infection, clinical data, predisposing factors, urinary catheter data, treatment, and outcome. RESULTS 106 patients (mean age 56 (SD 22) years; 43% females) with MSSA bacteriuria were identified, comprising 0.18% of bacteriurias in our hospital during the study period. Only 6.6% were admitted from long-term care facilities. 30% were hospital-acquired, with crude mortality rate 28% vs. 8% in community-acquired bacteriuria (P<0.05). Charlson Comorbidity Index was 2.7 (SD 3.2). 41% had a Foley urinary catheter. 12% with MSSA bacteriuria had concurrent MSSA bacteremia. In bacteremic patients vs. non-bacteremic patients: fever in 58% vs. 26% (P<0.025), antibiotics administered in 92% vs. 60% (P<0.04), and death by 28th post-discharge day 58% vs. 9% (P<0.001). CONCLUSIONS MSSA bacteriuria is rare, equally frequent in both genders, occurs in younger patients than previously described, and may occur even without a urinary catheter. Hospital-acquired bacteriuria and bacteremia are risk factors for mortality.

Risk factors for community-acquired pneumonia with influenza A/H1N1 in southern Israel §

OBJECTIVES To determine the risk factors for community-acquired pneumonia (CAP) with influenza A/H1N1 flu in our region. METHODS Adult patients with CAP from July 2009 to February 2010 who were screened for influenza A/H1N1 were identified retrospectively. This was a retrospective case-control study. Cases had CAP with influenza A/H1N1 and controls had CAP without influenza A/H1N1. Patient files were reviewed for demographics, clinical characteristics, treatment, and outcome. RESULTS Three hundred and eight patients with CAP were identified: 107 cases and 201 controls. For cases vs. controls there were significant differences in the following: median age (40 (range 18-82) vs. 56 (range 18-89) years; p<0.001), female gender (63.6% vs. 44.3%; p<0.05), Bedouin Arab origin (41.1% vs. 26.4%; p<0.05), pyrexia (97.6% vs. 88.5%; p<0.01), cough (96.3% vs. 75%; p<0.05), admission to the intensive care unit (18.7% vs. 10.6%; p<0.05), and CURB-65 score ≥ 3 (2.8% vs. 11.4%; p<0.05). Laboratory values including white blood cell (WBC) and platelet counts were lower in cases than in controls, whereas creatine phosphokinase and lactate dehydrogenase levels were higher (p<0.01). By logistic regression models, young age, Bedouin origin, and lower WBC and platelet counts were independent risk factors for the acquisition of CAP with influenza A/H1N1. CONCLUSIONS In our region CAP with influenza A/H1N1 occurred in younger females of Bedouin Arab origin with less co-morbidity. No difference in mortality was found. We believe that inequalities in socioeconomic conditions could explain our findings.

Shewanella spp. infection following treatment for upper gastrointestinal bleeding

Shewanella spp. are an uncommon cause of human infection, with exposure to water being the commonest source. We report a patient with a malignancy and upper gastrointestinal bleeding who underwent a gastric lavage followed by an endoscopy as part of her investigations. She subsequently developed Shewanella spp. bacteraemia without any clinical source of infection.