Implementation of a diagnostic stewardship intervention to improve blood-culture utilization in 2 surgical ICUs: Time for a blood-culture change.

OBJECTIVE: We compared the number of blood-culture events before and after the introduction of a blood-culture algorithm and provider feedback. Secondary objectives were the comparison of blood-culture positivity and negative safety signals before and after the intervention. DESIGN: Prospective cohort design. SETTING: Two surgical intensive care units (ICUs): general and trauma surgery and cardiothoracic surgery. PATIENTS: Patients aged ≥18 years and admitted to the ICU at the time of the blood-culture event. METHODS: We used an interrupted time series to compare rates of blood-culture events (ie, blood-culture events per 1,000 patient days) before and after the algorithm implementation with weekly provider feedback. RESULTS: The blood-culture event rate decreased from 100 to 55 blood-culture events per 1,000 patient days in the general surgery and trauma ICU (72% reduction; incidence rate ratio [IRR], 0.38; 95% confidence interval [CI], 0.32-0.46; P < .01) and from 102 to 77 blood-culture events per 1,000 patient days in the cardiothoracic surgery ICU (55% reduction; IRR, 0.45; 95% CI, 0.39-0.52; P < .01). We did not observe any differences in average monthly antibiotic days of therapy, mortality, or readmissions between the pre- and postintervention periods. CONCLUSIONS: We implemented a blood-culture algorithm with data feedback in 2 surgical ICUs, and we observed significant decreases in the rates of blood-culture events without an increase in negative safety signals, including ICU length of stay, mortality, antibiotic use, or readmissions.

SARS-CoV-2 reinfection across a spectrum of immunological states.

Purpose: Several cases of symptomatic reinfection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after full recovery from a prior episode have been reported. As reinfection has become an increasingly common phenomenon, an improved understanding of the risk factors for reinfection and the character and duration of the serological responses to infection and vaccination is critical for managing the coronavirus disease 2019 (COVID-19) pandemic. Methods: We described four cases of SARS-CoV-2 reinfection in individuals representing a spectrum of healthy and immunocompromised states, including (1) a healthy 41-year-old pediatrician, (2) an immunocompromised 31-year-old with granulomatosis with polyangiitis, (3) a healthy 26-year-old pregnant woman, and (4) a 50-year-old with hypertension and hyperlipidemia. We performed confirmatory quantitative reverse transcription-polymerase chain reaction and qualitative immunoglobulin M and quantitative IgG testing on all available patient samples to confirm the presence of infection and serological response to infection. Results: Our analysis showed that patients 1 and 2, a healthy and an immunocompromised patient, both failed to mount a robust serologic response to the initial infection. In contrast, patients 3 and 4, with minimal comorbid disease, both mounted a strong serological response to their initial infection, but were still susceptible to reinfection. Conclusion: Repeat episodes of COVID-19 are capable of occurring in patients regardless of the presence of known risk factors for infection or level of serological response to infection, although this did not trigger critical illness in any instance.

Low utilisation of bronchoscopy to assess COVID-19 respiratory infection: a multicenter experience.

OBJECTIVE: For the diagnosis of COVID-19, the yield of nasopharyngeal (NP) swabs is unclear, and bronchoalveolar lavage (BAL) is obtained to confirm the diagnosis. We assessed the utilisation of bronchoscopy for COVID-19 diagnosis in a multicenter study and compared the diagnostic yield of BAL versus NP swabs. METHODS: This retrospective study included all patients who were admitted with clinical presentation concerning for COVID-19 and underwent BAL from 1 March to 31 July 2020 at four tertiary care centres in North America. We also compared concordance of BAL with NP swabs for diagnosis of COVID-19 infection. RESULTS: Fifty-three patients, with clinical suspicion for COVID-19 and admitted for respiratory failure, underwent bronchoscopy to collect BAL for SARS-CoV-2 testing. During the same period, 2039 bronchoscopies were performed on patients not infected with COVID-19. Of 42 patients with NP swabs and BAL collected within ≤7 days, 1 was NP swab negative but positive by BAL for SARS-CoV-2 (n=1/42 (2.4%)). Across a wide array of testing platforms, the overall agreement between NP swabs and BAL results was 97.6% (95% CI: 93.0% to 100%) with Cohen's k of 0.90 (95% CI: 0.69 to 1.00). The sensitivity, specificity, positive and negative predictive values of NP swabs compared with BAL were 83.3% (95% CI: 53.5% to 100%), 100%, 100% and 97.3% (95% CI: 92.1% to 100%), respectively. CONCLUSIONS: BAL was used infrequently to assess COVID-19 in busy institutions. NP swabs have a high concordance with BAL for COVID-19 testing, but negative NP swabs should be confirmed with BAL when clinical suspicion is high.

Early experience with universal preprocedural testing for SARS-CoV-2 in a relatively low-prevalence area.

We implemented universal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing of patients undergoing surgical procedures as a means to conserve personal protective equipment (PPE). The rate of asymptomatic coronavirus disease 2019 (COVID-19) was <0.5%, which suggests that early local public health interventions were successful. Although our protocol was resource intensive, it prevented exposures to healthcare team members.

Evaluation of the National Healthcare Safety Network standardized infection ratio risk adjustment for healthcare-facility-onset Clostridioides difficile infection in intensive care, oncology, and hematopoietic cell transplant units in general acute-care hospitals.

OBJECTIVE: To evaluate the National Health Safety Network (NHSN) hospital-onset Clostridioides difficile infection (HO-CDI) standardized infection ratio (SIR) risk adjustment for general acute-care hospitals with large numbers of intensive care unit (ICU), oncology unit, and hematopoietic cell transplant (HCT) patients. DESIGN: Retrospective cohort study. SETTING: Eight tertiary-care referral general hospitals in California. METHODS: We used FY 2016 data and the published 2015 rebaseline NHSN HO-CDI SIR. We compared facility-wide inpatient HO-CDI events and SIRs, with and without ICU data, oncology and/or HCT unit data, and ICU bed adjustment. RESULTS: For these hospitals, the median unmodified HO-CDI SIR was 1.24 (interquartile range [IQR], 1.15-1.34); 7 hospitals qualified for the highest ICU bed adjustment; 1 hospital received the second highest ICU bed adjustment; and all had oncology-HCT units with no additional adjustment per the NHSN. Removal of ICU data and the ICU bed adjustment decreased HO-CDI events (median, -25%; IQR, -20% to -29%) but increased the SIR at all hospitals (median, 104%; IQR, 90%-105%). Removal of oncology-HCT unit data decreased HO-CDI events (median, -15%; IQR, -14% to -21%) and decreased the SIR at all hospitals (median, -8%; IQR, -4% to -11%). CONCLUSIONS: For tertiary-care referral hospitals with specialized ICUs and a large number of ICU beds, the ICU bed adjustor functions as a global adjustment in the SIR calculation, accounting for the increased complexity of patients in ICUs and non-ICUs at these facilities. However, the SIR decrease with removal of oncology and HCT unit data, even with the ICU bed adjustment, suggests that an additional adjustment should be considered for oncology and HCT units within general hospitals, perhaps similar to what is done for ICU beds in the current SIR.

Vitreous and Aqueous Penetration of Orally Administered Trimethoprim-Sulfamethoxazole Combination in Humans.

PURPOSE: To determine the penetration of orally administered trimethoprim (TMP)-sulfamethoxazole (SMX) into the aqueous and vitreous cavity of noninflamed human eyes. METHODS: Nine adult patients undergoing cataract surgery and 10 adult patients undergoing pars plana vitrectomy were given 3 doses of oral TMP-SMX every 12 hours before the surgery. Aqueous and blood samples were collected from patients undergoing cataract surgery; vitreous and blood samples were collected from patients undergoing vitrectomy. The levels of TMP and SMX were analyzed using high-performance liquid chromatography and were compared with the mean minimum inhibitory concentrations (MIC) of potential ocular pathogens. RESULTS: TMP-SMX was present in all samples. Among eyes undergoing cataract surgery, the mean concentrations of TMP in aqueous and blood were 0.341 ± 0.141 µg/mL (mean ± SD) and 1.501 ± 0.433 µg/mL and of SMX were 5.259 ± 0.929 µg/mL and 11.835 ± 2.100 µg/mL, respectively. Among eyes undergoing vitrectomy, the mean concentrations of TMP in vitreous and blood were 1.864 ± 0.807 µg/mL and 4.591 ± 2.979 µg/mL and of SMX were 5.910 ± 2.705 µg/mL and 39.289 ± 15.469 µg/mL, respectively. MIC levels were achieved against many bacterial pathogens, including methicillin-resistant Staphylococcus aureus. CONCLUSIONS: TMP-SMX penetrates both the aqueous and vitreous cavities when given orally. The components reach therapeutic inhibitory concentrations in the ocular cavity against many potential pathogens.

Physician use of parasite tests in the United States from 1997 to 2006 and in a Utah Cryptosporidium outbreak in 2007.

Parasitic infection is uncommon in the United States, but surveys suggest that physicians test when the presence of parasites is unlikely and fail to order appropriate testing when suspicion is high. Numerous studies confirm that immunoassays are more sensitive for Giardia and Cryptosporidium detection, but our experience was that physicians preferentially used ovum and parasite examination (O&P). We conducted a retrospective study of fecal parasite testing at a referral laboratory nationally (1997 to 2006) and during a Cryptosporidium outbreak (Utah, 2007) to correlate physician use of O&P and enzyme immunoassays (EIAs) with the yield of parasites detected. Nationally, of 170,671 episodes, 76.0% (n = 129,732) included O&P, 27.9% (n = 47,666) included Giardia EIA, and 5.7% (n = 9,754) included Cryptosporidium EIA. Most pathogens were Giardia or Cryptosporidium. More episodes were positive when EIA was performed (n = 1,860/54,483 [3.4%]) than when O&P only was performed (n = 1,667/116,188 [1.4%]; P < 0.001), and EIA was more sensitive than O&P. However, more O&P results were positive among patients with both O&P and EIA performed (2.5%) than among those with O&P only performed (1.4%; P < 0.001), suggesting that patients tested by O&P only may have been at lower risk. During the first 10 weeks of the outbreak, physicians also preferentially used O&P over EIA, but no Cryptosporidium cases were detected by O&P. We conclude that clinicians frequently use O&P testing when test performance and epidemiology support the use of immunoassays or no testing. We recommend that stool O&P be limited to patients with negative immunoassay results and persistent symptoms or individuals at increased risk for non-Giardia, non-Cryptosporidium infection. An evidence-based algorithm for the evaluation of patients with suspected intestinal parasitic infection is proposed.