Ari A. Robicsek, M.D.

Ari A. Robicsek, M.D.

Ari A. Robicsek, M.D.

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Conditions & Procedures

Conditions

Bone and Joint Infection, Fever of Unknown Origin, Illness in Returning Travelers, Infection Associated with Healthcare Contact, Infection in Patients over 18 Years of Age, Infections Associated with Implanted Devices, New Diagnosis HIV or Ongoing Care, Skin and Soft Tissue Infection

Procedures

Appropriate Utilization of Antimicrobials, Diagnosis and Treatment of Infections during Immunosuppression, Medical Informatics, Prevention of Infection, Surveillance and Prevention of Infection in Healthcare

General Information

Gender

Male

Affiliation

NorthShore Medical Group

Expertise

Infectious Diseases

Academic Rank

Clinical Associate Professor

Languages

English

Board Certified

Infectious Disease, Internal Medicine

Clinical Service

Infectious Diseases

Education, Training & Fellowships

Medical School

University of Toronto Medical School, 1998

Internship

Mount Sinai Hospital - Canada, 1999

Residency

Toronto General Hospital, 2001

Fellowship

Toronto General Hospital, 2002
Harvard Medical School - Massachusetts General Hospital, 2005

Locations

A

NorthShore Medical Group

1000 Central St.
Suite 800
Evanston, IL 60201
847.657.5959 847.733.5331 fax This location is wheelchair accessible.

Insurance

Every effort has been made to ensure the accuracy of the information in this directory. However, some changes may occur between updates. Please check with your provider to ensure that he or she participates in your health plan.

Aetna HMO/PPO/POS
BCBS HMOI
BCBS PPO *except Blue Choice IL
Beechstreet PPO
CCN PPO
CIGNA Choice Fund
CIGNA Choice Fund PPO
CIGNA EPO
CIGNA Network
CIGNA Network Open Access
CIGNA POS
CIGNA POS Open Access
CIGNA PPO
CIGNA:Open Access Plus
First Health PPO
Galaxy PPO
Great West POS
Great West PPO
Healthcares Finest Network PPO
Humana Choice Care PPO
Humana IPA--HMO
Humana POS
Humana PPO
Land of Lincoln
Medicare
Multiplan Admar PPO
Multiplan Formost PPO
Multiplan Health Network PPO
Multiplan Wellmark PPO
NorthShore Employee Network I (EPO Option)
NorthShore Employee Network II (EPO Plus & CDHP)
PHCS PPO
Preferred Plan PPO
Railroad Medicare - Cook County
UHC *except Core & Navigate
Unicare PPO

Publications

  • The Predictive Utility of Prior Positive Urine Cultures.

    Clinical infectious diseases : an official publication of the Infectious Diseases Society of America 2014 Jul 21

    Authors: MacFadden DR,
    Abstract
     A patient's prior urine cultures are often considered when choosing empiric antibiotic therapy for a suspected urinary tract infection. We sought to evaluate how well a patient's previous urine cultures predict the identity and susceptibility of subsequent urine cultures.
     We conducted a multi-national, multi-centre, retrospective cohort study, including 22,019 pairs of positive urine cultures from 4,351 patients, across two healthcare systems in Toronto, Ontario and Chicago, Illinois. We examined the probability of the same organism being identified from the same patient's positive urine culture as a function of time elapsed from the previous positive urine specimen; in cases where the same organism was identified we also examined the likelihood of the organism exhibiting the same or better antimicrobial susceptibility profile.
     At 4-8 weeks between cultures, correspondence of isolate identity was 57%(95%CI: 55-59%), and at >32 weeks was 49%(95%CI:48-50%), still greater than expected by chance(p<0.001). At 4-8 weeks, a same or better susceptibility profile was found in 83%(95%CI:81-85%) of isolate pairs, and at >32 weeks 75%(95%CI:73-77%), still greater than expected by chance(p<0.001). Despite high local rates of ciprofloxacin resistance in urine isolates across all patients (40%,95%CI 39.5-40.5%), ciprofloxacin resistance was less than 20% among patients with a prior ciprofloxacin sensitive organism and no subsequent fluoroquinolone exposure.
     A patient's prior urine culture results are useful in predicting the identity and susceptibility of a current positive urine culture. In areas of high fluoroquinolone resistance, Ciprofloxacin can be used empirically when prior urine culture results indicate a ciprofloxacin-susceptible organism and no history of intervening fluoroquinolone use.
    PMID: 25048850 [PubMed - as supplied by publisher]
  • A technology-based quality innovation to identify undiagnosed hypertension among active primary care patients.

    Annals of family medicine 2014 Jul

    Authors: Rakotz MK,
    Abstract
    The goal of this study was to develop a technology-based strategy to identify patients with undiagnosed hypertension in 23 primary care practices and integrate this innovation into a continuous quality improvement initiative in a large, integrated health system.
    In phase 1, we reviewed electronic health records (EHRs) using algorithms designed to identify patients at risk for undiagnosed hypertension. We then invited each at-risk patient to complete an automated office blood pressure (AOBP) protocol. In phase 2, we instituted a quality improvement process that included regular physician feedback and office-based computer alerts to evaluate at-risk patients not screened in phase 1. Study patients were observed for 24 additional months to determine rates of diagnostic resolution.
    Of the 1,432 patients targeted for inclusion in the study, 475 completed the AOBP protocol during the 6 months of phase 1. Of the 1,033 at-risk patients who remained active during phase 2, 740 (72%) were classified by the end of the follow-up period: 361 had hypertension diagnosed, 290 had either white-coat hypertension, prehypertension, or elevated blood pressure diagnosed, and 89 had normal blood pressure. By the end of the follow-up period, 293 patients (28%) had not been classified and remained at risk for undiagnosed hypertension.
    Our technology-based innovation identified a large number of patients at risk for undiagnosed hypertension and successfully classified the majority, including many with hypertension. This innovation has been implemented as an ongoing quality improvement initiative in our medical group and continues to improve the accuracy of diagnosis of hypertension among primary care patients.
    PMID: 25024244 [PubMed - as supplied by publisher]
  • Reply to Daniell.

    Infection control and hospital epidemiology : the official journal of the Society of Hospital Epidemiologists of America 2014 Jan

    Authors: Ridgway JP,
    Abstract
    Methicillin-resistant Staphylococcus aureus (MRSA) nasal colonization among inpatients is a well-established risk factor for MRSA infection during the same hospitalization, but the long-term risk of MRSA infection is uncertain. We performed a retrospective cohort study to determine the one-year risk of MRSA infection among inpatients with MRSA-positive nasal polymerase chain reaction (PCR) tests confirmed by positive nasal culture (Group 1), patients with positive nasal PCR but negative nasal culture (Group 2), and patients with negative nasal PCR (Group 3).
    Subjects were adults admitted to a four-hospital system between November 1, 2006 and March 31, 2011, comprising 195,255 admissions. Patients underwent nasal swab for MRSA PCR upon admission; if positive, nasal culture for MRSA was performed; if recovered, MRSA was tested for Panton-Valentine Leukocidin (PVL). Outcomes included MRSA-positive clinical culture and skin and soft tissue infection (SSTI). Group 1 patients had a one-year risk of MRSA-positive clinical culture of 8.0% compared with 3.0% for Group 2 patients, and 0.6% for Group 3 patients (p<0.001). In a multivariable model, the hazard ratios for future MRSA-positive clinical culture were 6.52 (95% CI, 5.57 to 7.64) for Group 1 and 3.40 (95% CI, 2.70 to 4.27) for Group 2, compared with Group 3 (p<0.0001). History of MRSA and concurrent MRSA-positive clinical culture were significant risk factors for future MRSA-positive clinical culture. Group 1 patients colonized with PVL-positive MRSA had a one-year risk of MRSA-positive clinical culture of 10.1%, and a one-year risk of MRSA-positive clinical culture or SSTI diagnosis of 21.7%, compared with risks of 7.1% and 12.5%, respectively, for patients colonized with PVL-negative MRSA (p = 0.04, p = 0.005, respectively).
    MRSA nasal colonization is a significant risk factor for future MRSA infection; more so if detected by culture than PCR. Colonization with PVL-positive MRSA is associated with greater risk than PVL-negative MRSA.
    PMID: 24334807 [PubMed - as supplied by publisher]
  • Molecular epidemiology of Escherichia coli sequence type 131 and Its H30 and H30-Rx subclones among extended-spectrum-β-lactamase-positive and -negative E. coli clinical isolates from the Chicago Region, 2007 to 2010.

    Antimicrobial agents and chemotherapy 2013 Dec

    Authors: Banerjee R,
    Abstract
    We assessed Escherichia coli ST131 and its H30 and H30-Rx subclones for virulence genes, antimicrobial resistance, and extended-spectrum beta-lactamase (ESBL) type. Although both subclones were associated with ESBL production, H30-Rx isolates had higher resistance scores and were associated specifically with CTX-M-15. Three virulence genes (iha, sat, and iutA) were more prevalent among H30 than non-H30 ST131 isolates. Thus, the H30 and H30-Rx subclones are more antimicrobial resistant and have virulence profiles that are distinct from those of non-H30 ST131 isolates.
    PMID: 24080662 [PubMed - as supplied by publisher]
  • Utility of prior screening for methicillin-resistant Staphylococcus aureus in predicting resistance of S. aureus infections.

    CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne 2013 Oct 15

    Authors: MacFadden DR, Elligsen M, Robicsek A, Ricciuto DR, Daneman N,
    Abstract
    Screening for methicillin-resistant Staphylococcus aureus (MRSA) is intended to reduce nosocomial spread by identifying patients colonized by MRSA. Given the widespread use of this screening, we evaluated its potential clinical utility in predicting the resistance of clinical isolates of S. aureus.
    We conducted a 2-year retrospective cohort study that included patients with documented clinical infection with S. aureus and prior screening for MRSA. We determined test characteristics, including sensitivity and specificity, of screening for predicting the resistance of subsequent S. aureus isolates.
    Of 510 patients included in the study, 53 (10%) had positive results from MRSA screening, and 79 (15%) of infecting isolates were resistant to methicillin. Screening for MRSA predicted methicillin resistance of the infecting isolate with 99% (95% confidence interval [CI] 98%-100%) specificity and 63% (95% CI 52%-74%) sensitivity. When screening swabs were obtained within 48 hours before isolate collection, sensitivity increased to 91% (95% CI 71%-99%) and specificity was 100% (95% CI 97%-100%), yielding a negative likelihood ratio of 0.09 (95% CI 0.01-0.3) and a negative predictive value of 98% (95% CI 95%-100%). The time between swab and isolate collection was a significant predictor of concordance of methicillin resistance in swabs and isolates (odds ratio 6.6, 95% CI 1.6-28.2).
    A positive result from MRSA screening predicted methicillin resistance in a culture-positive clinical infection with S. aureus. Negative results on MRSA screening were most useful for excluding methicillin resistance of a subsequent infection with S. aureus when the screening swab was obtained within 48 hours before collection of the clinical isolate.
    PMID: 24016794 [PubMed - as supplied by publisher]
  • Predictors and molecular epidemiology of community-onset extended-spectrum β-lactamase-producing Escherichia coli infection in a Midwestern community.

    Infection control and hospital epidemiology : the official journal of the Society of Hospital Epidemiologists of America 2013 Sep

    Authors: Banerjee R,
    Abstract
    To identify predictors of community-onset extended-spectrum β-lactamase (ESBL)-producing Escherichia coli infection.
    Prospective case-control study.
    Acute care hospitals and ambulatory clinics in the Chicago, Illinois, region.
    Adults with E. coli clinical isolates cultured in ambulatory settings or within 48 hours of hospital admission.
    Cases were patients with ESBL-producing E. coli clinical isolates cultured in ambulatory settings or within 48 hours of admission, and controls were patients with non-ESBL-producing E. coli isolates, matched to cases by specimen, location, and date. Clinical variables were ascertained through interviews and medical record review. Molecular methods were used to identify ESBL types, sequence type ST131, and aac(6')-Ib-cr.
    We enrolled 94 cases and 158 controls. Multivariate risk factors for ESBL-producing E. coli infection included travel to India in the past year (odds ratio [OR], 14.40 [95% confidence interval (CI), 2.92-70.95]), ciprofloxacin use (OR, 3.92 [95% CI, 1.90-8.1]), and age (OR, 1.04 [95% CI, 1.02-1.06]). Case isolates exhibited high prevalence of CTX-M-15 (78%), ST131 (50%), and aac(6')-Ib-cr (66% of isolates with CTX-M-15).
    Providers should be aware of the increased risk of ESBL-producing E. coli infection among returned travelers, especially those from India.
    PMID: 23917909 [PubMed - as supplied by publisher]
  • Electronic health record-based detection of risk factors for Clostridium difficile infection relapse.

    Infection control and hospital epidemiology : the official journal of the Society of Hospital Epidemiologists of America 2013 Apr

    Authors: Hebert C,
    Abstract
    A major challenge in treating Clostridium difficile infection (CDI) is relapse. Many new therapies are being developed to help prevent this outcome. We sought to establish risk factors for relapse and determine whether fields available in an electronic health record (EHR) could be used to identify high-risk patients for targeted relapse prevention strategies.
    Retrospective cohort study.
    Large clinical data warehouse at a 4-hospital healthcare organization.
    Data were gathered from January 2006 through October 2010. Subjects were all inpatient episodes of a positive C. difficile test where patients were available for 56 days of follow-up.
    Relapse was defined as another positive test between 15 and 56 days after the initial test. Multivariable regression was performed to identify factors independently associated with CDI relapse.
    Eight hundred twenty-nine episodes met eligibility criteria, and 198 resulted in relapse (23.9%). In the final multivariable analysis, risk of relapse was associated with age (odds ratio [OR], 1.02 per year [95% confidence interval (CI), 1.01-1.03]), fluoroquinolone exposure in the 90 days before diagnosis (OR, 1.58 [95% CI, 1.11-2.26]), intensive care unit stay in the 30 days before diagnosis (OR, 0.47 [95% CI, 0.30-0.75]), cephalosporin (OR, 1.80 [95% CI, 1.19-2.71]), proton pump inhibitor (PPI; OR, 1.55 [95% CI, 1.05-2.29]), and metronidazole exposure after diagnosis (OR, 2.74 [95% CI, 1.64-4.60]). A prediction model tuned to ensure a 50% probability of relapse would flag 14.6% of CDI episodes.
    Data from a comprehensive EHR can be used to identify patients at high risk for CDI relapse. Major risk factors include antibiotic and PPI exposure.
    PMID: 23466915 [PubMed - as supplied by publisher]
  • Abrupt emergence of a single dominant multidrug-resistant strain of Escherichia coli.

    The Journal of infectious diseases 2013 Mar 15

    Authors: Johnson JR,
    Abstract
    Fluoroquinolone-resistant Escherichia coli are increasingly prevalent. Their clonal origins--potentially critical for control efforts--remain undefined.
    Antimicrobial resistance profiles and fine clonal structure were determined for 236 diverse-source historical (1967-2009) E. coli isolates representing sequence type ST131 and 853 recent (2010-2011) consecutive E. coli isolates from 5 clinical laboratories in Seattle, Washington, and Minneapolis, Minnesota. Clonal structure was resolved based on fimH sequence (fimbrial adhesin gene: H subclone assignments), multilocus sequence typing, gyrA and parC sequence (fluoroquinolone resistance-determining loci), and pulsed-field gel electrophoresis.
    Of the recent fluoroquinolone-resistant clinical isolates, 52% represented a single ST131 subclonal lineage, H30, which expanded abruptly after 2000. This subclone had a unique and conserved gyrA/parC allele combination, supporting its tight clonality. Unlike other ST131 subclones, H30 was significantly associated with fluoroquinolone resistance and was the most prevalent subclone among current E. coli clinical isolates, overall (10.4%) and within every resistance category (11%-52%).
    Most current fluoroquinolone-resistant E. coli clinical isolates, and the largest share of multidrug-resistant isolates, represent a highly clonal subgroup that likely originated from a single rapidly expanded and disseminated ST131 strain. Focused attention to this strain will be required to control the fluoroquinolone and multidrug-resistant E. coli epidemic.
    PMID: 23288927 [PubMed - as supplied by publisher]
  • Epidemiology of methicillin-resistant Staphylococcus aureus carriage and MRSA surgical site infections in patients undergoing colorectal surgery: a cohort study in two centers.

    Surgical infections 2012 Dec

    Authors: Huttner B,
    Abstract
    Surgical site infections (SSIs) after colorectal surgery usually are caused by commensal intestinal bacteria. Methicillin-resistant Staphylococcus aureus (MRSA) may be responsible for additional SSI-related morbidity. The aim of this retrospective cohort study was to describe the epidemiology of SSIs caused by MRSA after colorectal surgery in two tertiary-care centers, one in Geneva, Switzerland (G), and the other in Chicago, Illinois (C).
    Adult patients undergoing colorectal resections during periods of universal screening for MRSA on admission were identified retrospectively. Demographic characteristics, surgery-related factors, and occurrence of MRSA SSI were compared in patients with and without MRSA carriage before surgery.
    There were 1,069 patients (G=194, C=875) with a median age of 67 years fulfilling the inclusion criteria. Of these, 45 patients (4.2%) had a positive MRSA screening result within 30 days before surgery (G=18, C=27; p<0.001). Ten patients (0.9%; G=6, C=4) developed MRSA SSI, detected a median of 17.5 days after surgery, but only two of them were MRSA-positive before surgery. Nine of the 45 MRSA carriers identified by screening received pre-operative prophylaxis with vancomycin (G 6/18, C 3/27), and 17 of these patients (37.8%; G 7/18, C 10/27) were started on MRSA decolonization therapy before surgery. Pre-operative administration of either decolonization or vancomycin was not protective against MRSA SSI (p=0.49).
    Methicillin-resistant S. aureus seems to be an infrequent cause of SSI after colorectal resections, even in MRSA carriers. Systematic universal screening for MRSA carriage prior to colorectal surgery may not be beneficial for the individual patient. Post-operative factors seem to be important in MRSA infections, as the majority of MRSA SSIs occurred in patients negative for MRSA carriage.
    PMID: 23240722 [PubMed - as supplied by publisher]

In the News

Jan 2014

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Novel H1N1: Dr. Ari Robicsek (Infectious Diseases)

Novel H1N1: Dr. Ari Robicsek (Infectious Diseases)

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