Jessica P. Ridgway

Demonstration of the Weighted-Incidence Syndromic Combination Antibiogram: An Empiric Prescribing Decision Aid

OBJECTIVE Healthcare providers need a better empiric antibiotic prescribing aid than the traditional antibiogram, which supplies no information on the relative frequency of organisms recovered in a given infection and which is uninformative in situations where multiple antimicrobials are used or multiple organisms are anticipated. We aimed to develop and demonstrate a novel empiric prescribing decision aid. DESIGN/SETTING This is a demonstration involving more than 9,000 unique encounters for abdominal-biliary infection (ABI) and urinary tract infection (UTI) to a large healthcare system with a fully integrated electronic health record (EHR). METHODS We developed a novel method of displaying microbiology data called the weighted-incidence syndromic combination antibiogram (WISCA) for 2 clinical syndromes, ABI and UTI. The WISCA combines simple diagnosis and microbiology data from the EHR to (1) classify patients by syndrome and (2) determine, for each patient with a given syndrome, whether a given regimen (1 or more agents) would have covered all the organisms recovered for their infection. This allows data to be presented such that clinicians can see the probability that a particular regimen will cover a particular infection rather than the probability that a single drug will cover a single organism. RESULTS There were 997 encounters for ABI and 8,232 for UTI. A WISCA was created for each syndrome and compared with a traditional antibiogram for the same period. CONCLUSIONS Novel approaches to data compilation and display can overcome limitations to the utility of the traditional antibiogram in helping providers choose empiric antibiotics.

Influenza Among Afebrile and Vaccinated Healthcare Workers

Among healthcare workers with influenza, half were afebrile. There was no significant difference in the rate of fever among individuals with influenza who had been previously vaccinated compared with those who had not been vaccinated (55% vs 39%; P = .33).

Documenting Penicillin Allergy: The Impact of Inconsistency.

Background Allergy documentation is frequently inconsistent and incomplete. The impact of this variability on subsequent treatment is not well described. Objective To determine how allergy documentation affects subsequent antibiotic choice. Design Retrospective, cohort study. Participants 232,616 adult patients seen by 199 primary care providers (PCPs) between January 1, 2009 and January 1, 2014 at an academic medical system. Main Measures Inter-physician variation in beta-lactam allergy documentation; antibiotic treatment following beta-lactam allergy documentation. Key Results 15.6% of patients had a reported beta-lactam allergy. Of those patients, 39.8% had a specific allergen identified and 22.7% had allergic reaction characteristics documented. Variation between PCPs was greater than would be expected by chance (all p<0.001) in the percentage of their patients with a documented beta-lactam allergy (7.9% to 24.8%), identification of a specific allergen (e.g. amoxicillin as opposed to “penicillins”) (24.0% to 58.2%) and documentation of the reaction characteristics (5.4% to 51.9%). After beta-lactam allergy documentation, patients were less likely to receive penicillins (Relative Risk [RR] 0.16 [95% Confidence Interval: 0.15–0.17]) and cephalosporins (RR 0.28 [95% CI 0.27–0.30]) and more likely to receive fluoroquinolones (RR 1.5 [95% CI 1.5–1.6]), clindamycin (RR 3.8 [95% CI 3.6–4.0]) and vancomycin (RR 5.0 [95% CI 4.3–5.8]). Among patients with beta-lactam allergy, rechallenge was more likely when a specific allergen was identified (RR 1.6 [95% CI 1.5–1.8]) and when reaction characteristics were documented (RR 2.0 [95% CI 1.8–2.2]). Conclusions Provider documentation of beta-lactam allergy is highly variable, and details of the allergy are infrequently documented. Classification of a patient as beta-lactam allergic and incomplete documentation regarding the details of the allergy lead to beta-lactam avoidance and use of other antimicrobial agents, behaviors that may adversely impact care quality and cost.

Clinical Significance of Methicillin-Resistant Staphylococcus aureus Colonization on Hospital Admission: One-Year Infection Risk

Background 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). Methodology/Principal Findings 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). Conclusions/Significance 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.

Predictive Utility of Prior Positive Urine Cultures

BACKGROUND A patients prior urine cultures are often considered when choosing empiric antibiotic therapy for a suspected urinary tract infection. We sought to evaluate how well previous urine cultures predict the identity and susceptibility of organisms in a patients subsequent urine cultures. METHODS We conducted a multinational, multicenter, retrospective cohort study, including 22 019 pairs of positive urine cultures from 4351 patients across 2 healthcare systems in Toronto, Ontario, and Chicago, Illinois. We examined the probability of the same organism being identified from the same patients 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. RESULTS At 4-8 weeks between cultures, the correspondence in isolate identity was 57% (95% confidence interval [CI], 55%-59%), and at >32 weeks it was 49% (95% CI, 48%-50%), still greater than expected by chance (P < .001). The susceptibility profile was the same or better in 83% (95% CI, 81%-85%) of isolate pairs at 4-8 weeks, and 75% (95% CI, 73%-77%) at >32 weeks, still greater than expected by chance (P < .001). Despite high local rates of ciprofloxacin resistance in urine isolates across all patients (40%; 95% CI, 39.5%-40.5%), ciprofloxacin resistance was <20% among patients with a prior ciprofloxacin sensitive organism and no subsequent fluoroquinolone exposure. CONCLUSIONS A patients 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 there has been no history of intervening fluoroquinolone use.

Performance characteristics and associated outcomes for an automated surveillance tool for bloodstream infection

BACKGROUND The objective of this study was to evaluate performance metrics and associated patient outcomes of an automated surveillance system, the blood Nosocomial Infection Marker (NIM). METHODS We reviewed records of 237 patients with and 36,927 patients without blood NIM using the National Healthcare Safety Network (NHSN) definition for laboratory-confirmed bloodstream infection (BSI) as the gold standard. We matched cases with noncases by propensity score and estimated attributable mortality and cost of NHSN-reportable central line-associated bloodstream infections (CLABSIs) and non-NHSN-reportable BSIs. RESULTS For patients with central lines (CL), the blood NIM had 73.2% positive predictive value (PPV), 99.9% negative predictive value (NPV), 89.2% sensitivity, and 99.7% specificity. For all patients regardless of CL status, the blood NIM had 53.6% PPV, 99.9% NPV, 84.0% sensitivity, and 99.9% specificity. For CLABSI cases compared with noncases, mortality was 17.5% versus 9.4% (P = .098), and median charge was

Candida dubliniensis Pneumonia: A Case Report and Review of Literature

143,935 (interquartile range [IQR],

Hepatic Failure in a Patient Receiving Itraconazole for Pulmonary Histoplasmosis-Case Report and Literature Review.

89,794-

Sensitivity of Surveillance Testing for Multidrug-Resistant Gram-Negative Bacteria in the Intensive Care Unit

257,447) versus

Which Patients in the Emergency Department Should Receive Preexposure Prophylaxis? Implementation of a Predictive Analytics Approach

115,267 (IQR,