Susceptibility to reinfection with SARS-CoV-2 virus relative to existing antibody concentrations and T cell response.

OBJECTIVES: We investigated the reinfection rate of vaccinated or convalescent immunized SARS-CoV-2 in 952 expatriate workers with SARS-CoV-2 serological antibody (Ab) patterns and surrogate T cell memory at recruitment and follow-up. METHODS: Trimeric spike, nucleocapsid, and neutralizing Abs were measured, along with a T cell stimulation assay, targeting SARS-CoV-2 memory in clusters of differentiation (CD) 4+ and CD8+ T cells. The subjects were then followed up for reinfection for up to 6 months. RESULTS: The seroprevalence positivity at enrollment was greater than 99%. The T cell reactivity in this population was 38.2%. Of the 149 (15.9%) participants that were reinfected during the follow-up period (74.3%) had nonreactive T cells at enrollment. Those who had greater than 100 binding Ab units/ml increase from the median concentration of antispike immunoglobulin G Abs had a 6% reduction in the risk of infection. Those who were below the median concentration had a 78% greater risk of infection. CONCLUSION: Significant immune protection from reinfection was observed in those who retained T cell activation memory. Additional protection was observed when the antispike was greater than the median value.

Emergence of highly resistant Candida auris in the United Arab Emirates: a retrospective analysis of evolving national trends.

Introduction: The Centers for Disease Prevention and Control lists Candida auris, given its global emergence, multidrug resistance, high mortality, and persistent transmissions in health care settings as one of five urgent threats. As a new threat, the need for surveillance of C. auris is critical. This is particularly important for a cosmopolitan setting and global hub such as the United Arab Emirates (UAE) where continued introduction and emergence of resistant variant strains is a major concern. Methods: The United Arab Emirates has carried out a 12 years of antimicrobial resistance surveillance (2010-2021) across the country, spanning all seven Emirates. A retrospective analysis of C. auris emergence from 2018-2021 was undertaken, utilising the demographic and microbiological data collected via a unified WHONET platform for AMR surveillance. Results: Nine hundred eight non-duplicate C. auris isolates were reported from 2018-2021. An exponential upward trend of cases was found. Most isolates were isolated from urine, blood, skin and soft tissue, and the respiratory tract. UAE nationals nationals comprised 29% (n = 186 of 632) of all patients; the remainder were from 34 other nations. Almost all isolates were from inpatient settings (89.0%, n = 809). The cases show widespread distribution across all reporting sites in the country. C. auris resistance levels remained consistently high across all classes of antifungals used. C. auris in this population remains highly resistant to azoles (fluconazole, 72.6% in 2021) and amphotericin. Echinocandin resistance has now emerged and is increasing annually. There was no statistically significant difference in mortality between Candida auris and Candida spp. (non-auris) patients (p-value: 0.8179), however Candida auris patients had a higher intensive care unit (ICU) admission rate (p-value <0.0001) and longer hospital stay (p < 0.0001) compared to Candida spp. (non-auris) patients. Conclusion: The increasing trend of C. auris detection and associated multidrug resistant phenotypes in the UAE is alarming. Continued C. auris circulation in hospitals requires enhanced infection control measures to prevent continued dissemination.

Outcomes of caspofungin use in the treatment of Candida-related urinary tract infections, a case series.

Echinocandins are generally excluded in the treatment of Candida-related urinary tract infections due to their poor urinary concentration. In the presence of fluconazole resistant Candida species, such as C. Glabrata and C. auris, alternative therapies are needed. We herein report the use of caspofungin for the treatment of 10 patients with candiduria, including C. auris. Mycological cure was achieved in 6 of 7 patients and clinical cure was achieved in 8 of 10 patients. Larger studies are needed to confirm our findings.

Subconjunctival dirofilariasis: a case report from the United Arab Emirates and review of literature from the Arabian Gulf region.

We report the second case of ocular dirofilariasis from the United Arab Emirates in a 53-year-old Indian male. In this case, the patient had no travel history and presented with severe ocular pain and redness. Clinical examination raised the suspicion of a parasitic infection, and a microscopic examination confirmed the diagnosis of Dirofilaria repens. Surgical intervention was performed, and the patient had good postoperative outcomes. To our knowledge, this was the fifth case of human dirofilariasis and the third of ocular dirofilariasis to be reported from an area where the parasite is not known to be endemic - the Arabian Gulf region.

Evaluation of post-vaccination immunoglobulin G antibodies and T-cell immune response after inoculation with different types and doses of SARS-CoV-2 vaccines: A retrospective cohort study.

Introduction: The induction and speed of production of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) immune biomarkers may vary by type and number of inoculated vaccine doses. This study aimed to explore variations in SARS-CoV-2 anti-spike (anti-S), anti-nucleocapsid (anti-N), and neutralizing immunoglobulin G (IgG) antibodies, and T-cell response by type and number of SARS-CoV-2 vaccine doses received. Methods: In a naturally exposed and SARS-CoV-2-vaccinated population, we quantified the anti-S, anti-N, and neutralizing IgG antibody concentration and assessed T-cell response. Data on socio-demographics, medical history, and history of SARS-CoV-2 infection and vaccination were collected. Furthermore, nasal swabs were collected to test for SARS-CoV-2 infection. Confounder-adjusted association between having equal or more than a median concentration of the three IgG antibodies and T-cell response by number and type of the inoculated vaccines was quantified. Results: We surveyed 952 male participants with a mean age of 35.5 years ± 8.4 standard deviations. Of them, 52.6% were overweight/obese, and 11.7% had at least one chronic comorbidity. Of the participants, 1.4, 0.9, 20.2, 75.2, and 2.2% were never vaccinated, primed with only one dose, primed with two doses, boosted with only one dose, and boosted with two doses, respectively. All were polymerase chain reaction-negative to SARS-CoV-2. BBIBP-CorV (Sinopharm) was the most commonly used vaccine (92.1%), followed by rAd26-S + rAd5-S (Sputnik V Gam-COVID-Vac) (1.5%) and BNT162b2 (Pfizer-BioNTech) (0.3%). Seropositivity to anti-S, anti-N, and neutralizing IgG antibodies was detected in 99.7, 99.9, and 99.3% of the study participants, respectively. The T-cell response was detected in 38.2% of 925 study participants. Every additional vaccine dose was significantly associated with increased odds of having ≥median concentration of anti-S [adjusted odds ratio (aOR), 1.34; 95% confidence interval (CI): 1.02-1.76], anti-N (aOR, 1.35; 95% CI: 1.03-1.75), neutralizing IgG antibodies (aOR, 1.29; 95% CI: 1.00-1.66), and a T-cell response (aOR, 1.48; 95% CI: 1.12-1.95). Compared with boosting with only one dose, boosting with two doses was significantly associated with increased odds of having ≥median concentration of anti-S (aOR, 13.8; 95% CI: 1.78-106.5), neutralizing IgG antibodies (aOR, 13.2; 95% CI: 1.71-101.9), and T-cell response (aOR, 7.22; 95% CI: 1.99-26.5) although not with anti-N (aOR, 0.41; 95% CI: 0.16-1.08). Compared with priming and subsequently boosting with BBIBP-CorV, all participants who were primed with BBIBP-CorV and subsequently boosted with BNT162b2 had ≥median concentration of anti-S and neutralizing IgG antibodies and 14.6-time increased odds of having a T-cell response (aOR, 14.63; 95% CI: 1.78-120.5). Compared with priming with two doses, boosting with the third dose was not associated, whereas boosting with two doses was significantly associated with having ≥median concentration of anti-S (aOR, 14.20; 95% CI: 1.85-109.4), neutralizing IgG (aOR, 13.6; 95% CI: 1.77-104.3), and T-cell response (aOR, 7.62; 95% CI: 2.09-27.8). Conclusion: Achieving and maintaining a high blood concentration of protective immune biomarkers that predict vaccine effectiveness is very critical to limit transmission and contain outbreaks. In this study, boosting with only one dose or with only BBIBP-CorV after priming with BBIBP-CorV was insufficient, whereas boosting with two doses, particularly boosting with the mRNA-based vaccine, was shown to be associated with having a high concentration of anti-S, anti-N, and neutralizing IgG antibodies and producing an efficient T-cell response.

Evaluation of three commercial SARS-CoV-2 serology assays in a tertiary care hospital in the United Arab Emirates.

BACKGROUND: Serology assays have the potential to support RT-PCR in the diagnosis of SARS-CoV-2 infection. We studied three commercially available immunoassays for their diagnostic accuracy from blood specimens collected from 93 patients. METHODS: Blood samples from patients with confirmed COVID-19 infection were analysed using three different Immunoassays (Roche total antibody assay, Abbott IgG assay and Euroimmun IgG assay). Sensitivity, specificity, precision and time of seroconversion were evaluated. RESULTS: The sensitivity of Roche, Abbott and Euroimmun assays was 38.7%, 35.5% and 25.0% respectively for specimens collected <10 days and 84.4%, 84.4% and 70.0% respectively for specimens collected ≥10 days after the first positive RT-PCR. The specificity of all the three assays in this study was 100%. The timing of seroconversion occurred at day 1, 7 or 14. CONCLUSIONS: The assays evaluated in this study have different sensitivities for detecting antibodies in SARS-CoV-2 infection. Sensitivity for detecting antibodies for all three assays was higher for specimens collected ≥10 days after first positive PCR compared with specimens collected <10 days. Time of seroconversion is variable and assay-dependent.

Comprehensive Approach to Reduce Surgical Site Infections in Patients Undergoing Neurosurgical Procedures.

Background: Surgical site infections (SSIs) are recognized complications of surgical procedures. Methicillin-resistant Staphylococcus aureus (MRSA) colonization increases the likelihood of developing SSIs. Decolonization of MRSA has been shown to reduce post-operative SSIs, therefore, the aim of this project was to identify and decolonize MRSA carriers and to tailor perioperative antibiotic prophylaxis to protect those at high risk for SSIs better. Methods: In September 2013, a quality improvement process initiative was implemented for pre-operative screening of MRSA nasal carriage for patients undergoing elective neurosurgical procedures. Those identified as colonized received a 10-day decolonization protocol that consisted of: oral doxycycline 100 mg twice daily or oral trimethoprim-sulfamethoxazole (TMP-SMX) DS twice daily; oral rifampin 600 mg daily; daily bathing with chlorhexidine; and twice daily use of mupirocin ointment in each nostril and under the fingernails. In addition to cefazolin (weight-based dosing), vancomycin (weight-based dosing) was recommended for perioperative prophylaxis in known MRSA carriers and patients undergoing surgical procedures involving hardware implantation irrespective of colonization status. We compared the results with our previously documented neurosurgical site infection rates (2012 and 2013 were 3.0 and 2.2%, respectively) Results: From 2014 to 2015, MRSA screening was done for 1,197 patients, of whom 52 (4.3%) were found to be colonized. Surgical site infections occurred in 14 procedures (1.4%) in 2014 and eight (0.8%) procedures in 2015, respectively. Methicillin-resistant Staphylococcus aureus remained responsible for most of these infections. None of the patients who underwent decolonization developed an infection (MRSA or otherwise). Conclusions: The overall rate of neurosurgical site infections can be reduced through a bundled approach of MRSA decolonization and change in perioperative antibiotic prophylaxis to include vancomycin for procedures involving hardware implantation irrespective of MRSA carriage state.

Assessment of the performance of CHROMagar KPC and Xpert Carba-R assay for the detection of carbapenem-resistant bacteria in rectal swabs: First comparative study from Abu Dhabi, United Arab Emirates.

OBJECTIVES: The objective of this study was to evaluate the performance of CHROMagar™ KPC compared with Xpert® Carba-R assay for the detection of carbapenem-resistant bacterial isolates from rectal swabs. METHODS: Rectal swabs were obtained from patients admitted to Cleveland Clinic Abu Dhabi (United Arab Emirates) over a period of 7 months and were screened for carbapenem resistance by either culture on CHROMagar KPC or carbapenemase production using the Xpert Carba-R molecular method. Further testing for carbapenem susceptibility of isolates recovered from CHROMagar KPC was performed using VITEK®2. RESULTS: A total of 1813 rectal swabs were screened, of which 61 (3.4%) were positive for carbapenem resistance by either one or both methods. Both methods were equally efficient in detecting carbapenem resistance in 37/61 swabs (60.7%), mostly positive for Klebsiella pneumoniae (22 isolates), of which 40.9% (9/22) carried blaOXA-48-like and blaNDM. Xpert Carba-R assay detected 12 additional swabs with negative CHROMagar KPC culture and revealed additional carbapenemase-producing organisms carrying blaOXA-48-like and/or blaNDM. CHROMagar KPC recovered organisms in nine swabs not detected by the genotypic method, 44.4% of which were K. pneumoniae. Three swabs yielded false-positive results (carbapenem-susceptible organisms) by both methods. Sensitivity and specificity were, respectively, 75.4% and 99.8% for CHROMagar KPC and 80% and 99.8% for Xpert Carba-R. CONCLUSION: This comparative study of CHROMagar KPC versus Xpert Carba-R in rectal swabs showed a slightly higher sensitivity for the PCR-based method. Whilst CHROMagar KPC provides a less expensive screening method, Xpert Carba-R may be more accurate and faster.

The Impact of Integrating Rapid PCR-Based Blood Culture Identification Panel to an Established Antimicrobial Stewardship Program in the United Arab of Emirates.

BACKGROUND: Studies have shown improvement in the outcome of blood stream infections (BSI) due to the use of Rapid PCR-Based Blood Culture Identification Panel (BCID) in Antimicrobial stewardship programs (ASP). There is currently no data on the use of BCID with ASP in the United Arab Emirates (UAE). METHOD: Pre-post quasiexperimental study included hospitalized patients with BSI, their positive blood cultures on BCID were studied in 2 groups: conventional culture with ASP (AS), and BCID with ASP (BCID). The primary outcomes were time to first appropriate antimicrobial therapy, infection related length of stay (LOS), ICU admission, 14 days bacteremia recurrence and in-hospital mortality. Secondary outcomes were 30 days reinfection rate, hospital cost and ASP interventions. RESULTS: Out of total 477 positive blood cultures, 206 (AS and BCID) with real BSI were included. The time needed for organism identification was shorter in the BCID group than in the AS group (1.3 h vs. 51 h; P = 0.0002). BCID had a shorter time to appropriate antimicrobial therapy than AS (17.8 h vs.45 h; P = 0.0004). No statistical difference was observed in mortality rate, 14 days bacteremia recurrence, ICU admission, hospital cost, LOS or ASP interventions. CONCLUSION: Implementing BCID to ASP significantly decreased the time needed to identify the organism and time to appropriate antimicrobial therapy. Similarly, LOS and hospital cost were reduced, however, the reduction was not statistically significant.

Persistent candidemia despite appropriate fungal therapy: First case of Candida auris from the United Arab Emirates.

In this case, we report an elderly patient with multiple chronic conditions and prolonged intensive care unit (ICU) stays who had recurrent Candida auris (C. auris) in blood despite antifungal therapy. C. auris was misidentified using conventional automated identification system as Candida haemulonii resulting in delayed diagnosis. The isolate showed increasing minimum inhibitory concentrations (MICs) to different antifungal drugs and persisted in the patient's blood before the patient deceased. This is the first case of C. auris reported from the United Arab Emirates (UAE); laboratories should be aware of this Candida species and should confirm suspected cases since it is an emerging multi-drug resistant and health-care associated Candida.

Fast Track to Accreditation: An Implementation Review of College of American Pathologists and International Organization for Standardization 15189 Accreditation.

CONTEXT: - This review examines challenges and opportunities in preparing laboratories in a startup phase for accreditation by both the College of American Pathologists (CAP) and International Organization for Standardization (ISO) 15189 in an international setting as it relates to our experience at Cleveland Clinic Abu Dhabi Laboratory. It also discusses some of the strategies used in executing those projects and the added advantages in pursuing both types of accreditations. OBJECTIVES: - To share our experience with CAP and ISO 15189 accreditations in a startup international operation in relation to the challenges encountered and implementation strategy success factors. DATA SOURCES: - MEDLINE (PubMed) database was used to review this topic as well as peer-reviewed articles and World Health Organization publications on the topic. CONCLUSIONS: - Accreditation is a perfect means toward building quality medical laboratories in a diverse workforce environment and improving patient safety. Further, it establishes a strong foundation on which any new operation can build a sustainable quality improvement culture. Accreditations by CAP and/or ISO are among the most reputable and well-established accreditation systems that clinical laboratories could aim for. As a result of both accreditations offering synergistic and complementing features, we recommend that any laboratory seeking excellence in quality and performance should consider exploring both. Key elements to success include having dedicated project management and change management support while preparing for accreditation. Laboratories seeking accreditation in early operational stages may face a number of challenges; however, significant opportunities will also be present to optimize various operational components from the beginning.

Comparison of antimicrobial activity between ceftolozane-tazobactam and ceftazidime-avibactam against multidrug-resistant isolates of Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa.

OBJECTIVE: This study compared the activity of ceftolozane-tazobactam and ceftazidime-avibactam against 120 bacterial strains, including extended-spectrum beta-lactamase (ESBL) producers, carbapenem-resistant Enterobacteriaceae (CRE), and Pseudomonas aeruginosa, isolated from patients admitted to Cleveland Clinic Abu Dhabi, United Arab Emirates. METHODS: In vitro susceptibility was tested using the Etest strip minimum inhibitory concentration (MIC) method, and PCR was used to characterize the carbapenemase enzymes produced by CRE strains. RESULTS: All 29 ESBL isolates were susceptible to ceftazidime-avibactam (MIC50 0.125µg/ml), whereas all but one were susceptible to ceftolozane-tazobactam (MIC50 0.38µg/ml). Twenty-seven (45%) CRE isolates were susceptible to ceftazidime-avibactam (MIC50 ≥256µg/ml), whereas only six (10%) isolates were susceptible to ceftolozane-tazobactam (MIC50 ≥256µg/ml). Very few NDM-1 isolates were susceptible to ceftazidime-avibactam, whereas the majority of OXA-48 isolates were susceptible. Twenty-nine (94%) P. aeruginosa isolates were susceptible to ceftazidime-avibactam (MIC50 1.5µg/ml), whereas 30 (97%) isolates were susceptible to ceftolozane-tazobactam (MIC50 0.75µg/ml). CONCLUSIONS: Ceftolozane-tazobactam and ceftazidime-avibactam showed comparable activity against ESBL and P. aeruginosa, with ceftazidime-avibactam having lower MICs against ESBL isolates and ceftolozane-tazobactam having lower MICs against P. aeruginosa. Ceftazidime-avibactam showed better activity against all CRE isolates except for those carrying the NDM-1 enzyme.

Comparison of 4th-Generation HIV Antigen/Antibody Combination Assay With 3rd-Generation HIV Antibody Assays for the Occurrence of False-Positive and False-Negative Results.

OBJECTIVE: To assess the false-positive and false-negative rates of a 4th-generation human immunodeficiency virus (HIV) assay, the Abbott ARCHITECT, vs 2 HIV 3rd-generation assays, the Siemens Centaur and the Ortho-Clinical Diagnostics Vitros. METHODS: We examined 123 patient specimens. In the first phase of the study, we compared 99 specimens that had a positive screening result via the 3rd-generation Vitros assay (10 positive, 82 negative, and 7 indeterminate via confirmatory immunofluorescent assay [IFA]/Western blot [WB] testing). In the second phase, we assessed 24 HIV-1 RNA-positive (positive result via the nuclear acid amplification test [NAAT] and negative/indeterminate results via the WB test) specimens harboring acute HIV infection. RESULTS: The 4th-generation ARCHITECT assay yielded fewer false-positive results (n = 2) than the 3rd-generation Centaur (n = 9; P = .02) and Vitros (n = 82; P <.001) assays. One confirmed positive case had a false-negative result via the Centaur assay. When specimens from the 24 patients with acute HIV-1 infection were tested, the ARCHITECT assay yielded fewer false-negative results (n = 5) than the Centaur (n = 10) (P = .13) and the other 3rd-generation tests (n = 16) (P = .002). CONCLUSIONS: This study indicates that the 4th-generation ARCHITECT HIV assay yields fewer false-positive and false-negative results than the 3rd-generation HIV assays we tested.

Implications of false positive serology of Toxoplasma gondii in a pre-transplant patient.

PATIENT: A 21-year-old white male with cystic fibrosis. CHIEF COMPLAINT: Pre-transplant workup in preparation for bilateral lung transplant. PAST MEDICAL HISTORY: Cystic fibrosis diagnosed at age 3, onset of insulin-dependent diabetes around age 20, and multiple hospitalizations for pulmonary and gastrointestinal complications. FAMILY AND SOCIAL HISTORY: The patient lives with his father and stepmother, has a pet bearded dragon, and has multiple tattoos and piercings. His stepmother has a cat, but he does not clean the litter box. PRINCIPAL LABORATORY FINDINGS: The pre-transplant workup included several tests for infectious diseases, tests of organ function, radiology studies, and markers of malignancy. The only significant finding was a positive Toxoplasma gondii (T. gondii) IgM titer (> or = 1:40) (reference values for IgM: negative; < 1:40, positive; > or = 1:40) and IgG (1:2048) (reference values for IgG: negative; < 1:16, equivocal; > or = 1:16 - < 1:256, positive; > or = 1:256). Testing was done by indirect immunofluorescence assay (IFA) in April 2012 in our hospital laboratory. The patient was treated with sulfadiazine, leucovorin, and pyrimethamine. Three months later (July), he returned for follow-up testing. Real-time polymerase chain reaction (PCR) for T. gondii DNA performed by a reference laboratory was negative. One month later (August), Toxoplasma serology was performed by enzyme-linked immunosorbent assay (ELISA) by a different reference laboratory and showed an elevated IgM of 0.95 IU/mL (reference values: negative; < 0.55 IU/mL, equivocal; > or = 0.55- < 0.65 IU/mL, positive; > or = 0.65 IU/mL) and a normal level of IgG (< 4 IU/mL). At this time, PCR was repeated and was negative. An additional month later (September), the patient's serology studies were performed at a third reference laboratory and showed an elevated IgM of 1.32 IU/mL (reference values: negative; 0.89, equivocal; 0.90 - 1.09, positive; > 1.10) and a normal IgG.

Clinical features of West Nile virus epidemic in Dallas, Texas, 2012.

In 2012, Texas has reported the highest number of West Nile virus (WNV) cases in the United States to the Centers for Disease Control and Prevention. In this report, we conducted a retrospective chart review of 57 patients with WNV disease and analyzed the clinical features of these patients. Our results revealed that 25 (44%) patients were diagnosed with West Nile fever and 32 (56%) with West Nile neuroinvasive disease (WNND). The median age for patients with WNND was 54.5 years, and those with encephalitis were more likely to be >60 years old. Pre-existing conditions such as hypertension and diabetes were more frequent in patients with WNND. Testing both serum and cerebrospinal fluid (CSF) for antibodies diagnosed more cases of WNND than just testing serum or CSF alone. The increasing number of WNV cases during this epidemic highlights the need to increase efforts to control mosquito populations and educate the general public.

Interpretation of positive molecular tests of common viruses in the cerebrospinal fluid.

Many central nervous system infections are historically difficult to diagnose. Polymerase chain reaction (PCR) has revolutionized the diagnosis of these infections because of their high sensitivity despite the lack of data on clinical usefulness. We conducted a retrospective study that included patients with positive cerebrospinal fluid (CSF) PCR for herpes simplex virus, varicella-zoster virus, JC virus, cytomegalovirus (CMV), and Epstein-Barr virus (EBV) between January 2009 and December 2011. The positive results were grouped into definite, likely, and possible true positives and likely false-positive categories based on pre-specified definitions specific to each virus. Of 1663 CSF viral PCR tests, 88 were positive (5%). The combined positive predictive value (PPV) was 58%. The PPVs were least for CMV and EBV at 29 and 37%, respectively. A positive CSF viral PCR result has to be interpreted with caution due to several false-positive results.

Multiple factors contribute to positive results for hepatitis A virus immunoglobulin M antibody.

CONTEXT: In the United States, a successful vaccination program for hepatitis A virus (HAV) infection has decreased both its incidence and the true positive rate for diagnostic immunoglobulin M (IgM) antibody to HAV in acute hepatitis. OBJECTIVE: To survey positive results of HAV IgM tests and determine the effect of changing ordering options. DESIGN: We reviewed all positive results for IgM antibody to HAV between January 2007 and December 2010. Patient demographics, clinical history, and laboratory data were recorded and the encounter, order, and reason for test reviewed. Each result was categorized as indicating acute, recent, resolved, or indeterminate HAV infection. RESULTS: A total of 10,735 tests were performed; 35 patients had 49 positive results. Most positive test results were associated with outpatient visits and were ordered in the assessment of patients with liver disease, but not clinical acute hepatitis. In the final analysis, 4 patients had acute hepatitis A and 20 individual patients had recent and/or resolved hepatitis. All but 1 of the remaining 11 patients had another established cause of liver disease with a positive IgM HAV antibody test result; data to determine causality were insufficient. The total number of tests requested annually decreased more than 35% with the introduction of computerized physician order entry. CONCLUSIONS: Current assays for IgM HAV antibodies are overused in the absence of clinical acute hepatitis; future clinical decision support may improve patterns of order entry. Most patients have findings consistent with HAV exposure but not acute hepatitis; dormant viral infection may be a continuing source of antigen.

Pseudo-outbreak of vancomycin-resistant-enterococcus (VRE) Colonization in a neonatal intensive care unit using spectra VRE surveillance medium.

From November 2011 through March 2012, we surveyed 272 babies in our neonatal intensive care unit for rectal colonization with vancomycin-resistant enterococci (VRE). Using Spectra VRE medium (Remel Diagnostics, Lenexa, KS), we identified one neonate colonized with vancomycin-resistant Enterococcus faecium. In addition, 55 (13%) of the surveillance cultures yielded false-positive results with vancomycin-susceptible Enterococcus faecalis. During the same time period, 580 rectal swabs were collected from adult patients resulting in 20 (3%) false-positive cultures. The difference in false-positive rates between cultures from babies and adults was statistically significant (P < 0.001), prompting an investigation of factors that might influence the elevated false-positive rate in the neonates including patient demographics, nutrition, and topical ointments applied at the time of testing. Older neonates, with a median age of 6 weeks, were more likely to have false-positive cultures than younger neonates with a median age of 3 weeks (P < 0.001). The younger neonates receiving Similac Expert Care products were less likely to have false-positive surveillance cultures than those receiving other formulas (P < 0.001). Application of topical products was not associated with false-positive cultures. The false-positive E. faecalis strains were typed by Diversilab Rep-PCR (bioMérieux, Marcy l'Etoile, France) and found to represent eight different groups of isolates. The utility of the Spectra VRE media appeared to be significantly impacted by the age of the patients screened.

Identification of non-diphtheriae corynebacterium by use of matrix-assisted laser desorption ionization-time of flight mass spectrometry.

We evaluated the Bruker Biotyper matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry for identification of 92 clinical isolates of Corynebacterium species in comparison to identification using rpoB or 16S rRNA gene sequencing. Eighty isolates (87%) yielded a score of ≥1.700, and all of these were correctly identified to the species level with the exception of Corynebacterium aurimucosum being misidentified as the closely related Corynebacterium minutissimum.