Central line-associated blood stream infection (CLABSI) due to Candida sojae in an infant with short bowel syndrome: The first human case report.

Central line associated blood stream infections (CLABSIs) in infants and children with intestinal failure due to short bowel syndrome may be caused by different organisms due to intestinal translocation and skin contamination. We report what we believe the first case of candidemia in an infant with short bowel syndrome caused by the environmental yeast Candida sojae that was initially misidentified as Candida tropicalis. We discuss its possible sources including a central venous catheter (CVC) and gut translocation and the differences between the two Candida species.

Staphylococcus pettenkoferi-positive Blood cultures in Hospitalized Patients in a Multi-site Tertiary Center.

Staphylococcus pettenkoferi (S.pettenkoferi), originally described in Germany in 2002 by Trülzsch et al, is a coagulase negative staphylococcus whose clinical relevance is yet to be determined. With about 10 case reports in the literature from several parts of the world, there is no data on S. pettenkoferi infection from the United States. This is a retrospective cohort study of 80 patients ≥ 18 years of age who had at least 1 S. pettenkoferi-positive blood culture, identified by matrix-assisted laser desorption/ionization time-of-flight at a tertiary academic center in Detroit, Michigan. We describe the features of S. pettenkoferi-positive blood cultures in order to identify cases of true bacteremia. The mean age of the cohort was 66 ± 16 years and 1 out of 3 had immunosuppressing conditions. No case of true S.pettenkoferi bacteremia was identified. More studies are needed to determine its role as a pathogen in the United States.

A laboratory model demonstrating the protective effects of surgical masks, face shields, and a combination of both in a speaking simulation.

BACKGROUND: The protection against aerosol transmission provided by masks vs face shields or in combination when speaking indoors is not well understood. METHODS: To simulate a human source, an aerosol generating system was made using a bacterial suspension in a nebulizer attached to an oxygen cylinder. A fan connected to the nebulizer created aerosols. Transmitted aerosols were detected using blood agar plates at 0.1524 and 1.8288 meters from source, simulating exposed person. The study was performed under controlled conditions at room temperature in a biohazard hood with high-efficiency particulate air (HEPA) filter and UV light. RESULTS: When face shields were used alone, significant numbers of bacterial colonies grew on blood agar plates. When a mask used alone for both the subjects (source and exposed), the blood agar yielded minimal colony forming units at both distances. When face shields were used in combination with masks, no significant improvement was observed as compared to masks alone. DISCUSSION: Our results were similar to what have been observed in related studies. CONCLUSIONS: Surgical masks alone provided good protection, surpassing the protection provided by face shields alone. Both used together provided the best protection, although the combined protection was similar to surgical masks use alone.

Pooling samples: a testing option for SARS-CoV-2 during a supply shortage.

Pooling of 1 positive sample with up to 5 negative samples prior to testing with the Cepheid GenXpert SARS-CoV-2 assay did not adversely impact detection of positive samples. At our current prevalence of 2%, it could save up to 70% of the test kits.

Non-O1, non-O139 Vibrio cholerae bacteremia in an urban academic medical center in the United States.

Non-O1, non-O139 Vibrio cholerae (NOVC) are genetically diverse strains that are generally non-pathogenic in healthy hosts. In immunocompromised patients or those with liver disease, NOVC have been shown to cause gastroenteritis, wound infections or sepsis and are often associated with high mortality rates. We report a case of a patient with liver cirrhosis and chronic venous insufficiency who was found to have NOVC bacteremia. The patient had recently visited Florida, USA but had no seafood consumption or exposure to aquatic environments. The patient was managed with antimicrobials, with a favorable outcome.

Diagnostic Molecular Microbiology: A 2018 Snapshot.

Molecular biological techniques have evolved expeditiously and in turn have been applied to the detection of infectious disease. Maturation of these technologies and their coupling with related technological advancement in fluorescence, electronics, digitization, nanodynamics, and sensors among others have afforded clinical medicine additional tools toward expedient identification of infectious organisms at concentrations and sensitivities previously unattainable. These advancements have been adapted in select settings toward addressing clinical demands for more timely and effective patient management.

Effects of maternal medication use on NGF and IL-6 levels in human breast milk.

BACKGROUND: The objective of this study was to evaluate the effect of maternal medications on nerve growth factor (NGF) and interleukin-6 (IL-6) levels in human breast milk (HBM). METHODS: A total of 30 samples of HBM were collected after consent from consecutively born term newborns. NGF and IL-6 concentrations were analyzed using ELISA assays from R&D Systems. The HBM samples were centrifuged, and the clear portion of the HBM after discarding the fat was analyzed and cytokine data were expressed as NGFC or IL-6C. Ten samples of HBM, which were not centrifuged, were also used in ELISA assays and cytokine data were expressed as NGFF or IL-6F. RESULTS: After exposure to NSAIDs (7636 ± 9610, mean ± SD, pg/mL), the NGFC levels in HBM were significantly higher as compared to those who were exposed to narcotics (522 ± 1000) (p = 0.008). NGFC and IL-6C levels positively correlated with each other in HBM (R = 0.194 p < 0.0001). NGFC levels (360 ± 237) were significantly lower than NGFF levels (888 ± 751) (p < 0.0001). IL-6F was higher than IL-6C levels without statistical significance. CONCLUSION: Further studies are warranted to elucidate effect of maternal medications on cytokine changes in HBM and effect of these cytokine changes on newborn gastrointestinal milieu.

Rotavirus infections in Detroit, USA, a region of low vaccine prevalence.

After a sharp drop of rotavirus (RV) infections at Children's Hospital of Michigan, Detroit, USA in 2010 season, we noted an increase in the number of cases during the 2011 season including some RV vaccine (RVV) recipients. This study was conducted to determine the circulating genotypes during 2011 season and whether the increase in RV diarrhea was caused by replacement genotypes. G and P genotypes were determined by RT PCR and nucleotide sequencing of selected strains was performed. The vaccination rate among study patients was 24 %. RV strains from 68 stool samples were genotyped including 18 from vaccinated children and 50 from unvaccinated children. The predominant G genotype was G1 (58.8 %) followed by G9 (17.7 %) and G4 (15.5 %). P[8] was the predominant P genotype (68 %) followed by P[6] (17.6 %) and P[4] (3 %). All G9 strains were associated with P[6]. The most prevalent G-P combination was G1P[8] (56 %), followed by G9P[6] (17.6 %). Similar proportions of RV genotypes were found among vaccinated and unvaccinated children. Our local data suggest that 5 years after the introduction of RVV there has been no genotype replacement. Although a small increase in G9P[6] frequency was noted, G1P[8] remained the predominant strain of RV in our inner city community in the Midwestern USA.

Evaluation of the FilmArray Blood Culture Identification Panel: Results of a Multicenter Controlled Trial.

Sepsis is a major cause of morbidity, mortality, and increased medical expense. Rapid diagnosis improves outcomes and reduces costs. The FilmArray blood culture identification panel (BioFire Diagnostics LLC, Salt Lake City, UT), a highly multiplexed PCR assay, can identify 24 etiologic agents of sepsis (8 Gram-positive, 11 Gram-negative, and 5 yeast species) and three antimicrobial resistance genes (mecA, vanA/B, and blaKPC) from positive blood culture bottles. It provides results in about 1 h with 2 min for assay setup. We present the results of an eight-center trial comparing the sensitivity and specificity of the panel with those of the laboratories' standard phenotypic identification techniques, as well as with molecular methods used to distinguish Acinetobacter baumannii from other members of the A. calcoaceticus-A. baumannii complex and to detect antimicrobial resistance genes. Testing included 2,207 positive aerobic blood culture samples, 1,568 clinical and 639 seeded. Samples were tested fresh or were frozen for later testing within 8 h after the bottles were flagged as positive by an automated blood culture system. At least one organism was detected by the panel in 1,382 (88.1%) of the positive clinical specimens. The others contained primarily off-panel organisms. The panel reported multiple organisms in 81 (5.86%) positive clinical specimens. The unresolved blood culture identification sensitivity for all target detections exceeded 96%, except for Klebsiella oxytoca (92.2%), which achieved 98.3% sensitivity after resolution of an unavoidable phenotypic error. The sensitivity and specificity for vanA/B and blaKPC were 100%; those for mecA were 98.4 and 98.3%, respectively.

Multicenter evaluation of Candida QuickFISH BC for identification of Candida species directly from blood culture bottles.

Candida species are common causes of bloodstream infections (BSI), with high mortality. Four species cause >90% of Candida BSI: C. albicans, C. glabrata, C. parapsilosis, and C. tropicalis. Differentiation of Candida spp. is important because of differences in virulence and antimicrobial susceptibility. Candida QuickFISH BC, a multicolor, qualitative nucleic acid hybridization assay for the identification of C. albicans (green fluorescence), C. glabrata (red fluorescence), and C. parapsilosis (yellow fluorescence), was tested on Bactec and BacT/Alert blood culture bottles which signaled positive on automated blood culture devices and were positive for yeast by Gram stain at seven study sites. The results were compared to conventional identification. A total of 419 yeast-positive blood culture bottles were studied, consisting of 258 clinical samples (89 C. glabrata, 79 C. albicans, 23 C. parapsilosis, 18 C. tropicalis, and 49 other species) and 161 contrived samples inoculated with clinical isolates (40 C. glabrata, 46 C. albicans, 36 C. parapsilosis, 19 C. tropicalis, and 20 other species). A total of 415 samples contained a single fungal species, with C. glabrata (n = 129; 30.8%) being the most common isolate, followed by C. albicans (n = 125; 29.8%), C. parapsilosis (n = 59; 14.1%), C. tropicalis (n = 37; 8.8%), and C. krusei (n = 17; 4.1%). The overall agreement (with range for the three major Candida species) between the two methods was 99.3% (98.3 to 100%), with a sensitivity of 99.7% (98.3 to 100%) and a specificity of 98.0% (99.4 to 100%). This study showed that Candida QuickFISH BC is a rapid and accurate method for identifying C. albicans, C. glabrata, and C. parapsilosis, the three most common Candida species causing BSI, directly from blood culture bottles.

Weissella confusa: problems with identification of an opportunistic pathogen that has been found in fermented foods and proposed as a probiotic.

Weissella confusa is found in fermented foods and has been suggested as a probiotic, but also causes sepsis and other serious infections in humans and animals. The incidence of human infections is underestimated partly due to confusion with viridans streptococci and partly due to difficulty making a definitive identification, even if the organism is recognized to belong to another genus, owing to the inability of commercial organism systems to identify it. We report our experiences identifying W. confusa isolated from two immune-compromised patients, both of whom developed sepsis with this organism. Two MicroScan gram positive combination panels, could not identify the organism because they did not have W. confusa in their data bases, but did not provide a false identification. Other laboratorians have reported failure to identify or false identifications of W. confusa with other commercial systems. W. confusa is in the data base of the RapID™ Str panel (Remel), which gave three incorrect, high probability results (≥95%). 16S rDNA sequencing identified the isolates as W. confusa. Maldi-Tof, performed by two of our reference laboratories, also correctly identified both isolates. Use of W. confusa as a probiotic should be approached with caution because its true incidence as an opportunisitic pathogen is unknown.

Diagnostic molecular microbiology: a 2013 snapshot.

Molecular testing has a large and increasing role in the diagnosis of infectious diseases. It has evolved significantly since the first probe tests were FDA approved in the early 1990s. This article highlights the uses of molecular techniques in diagnostic microbiology, including "older," as well as innovative, probe techniques, qualitative and quantitative RT-PCR, highly multiplexed PCR panels, some of which use sealed microfluidic test cartridges, MALDI TOF, and nuclear magnetic resonance. Tests are grouped together by technique and target. Tests with similar roles for similar analytes are compared with respect to benefits, drawbacks, and possible problems.

Aerosolized vaccine as an unexpected source of false-positive Bordetella pertussis PCR results.

When 13 of 13 nasal wash specimens from a single pediatrician's office tested positive for low quantities of Bordetella pertussis DNA, we suspected prelaboratory contamination. Investigation revealed that Pentacel and Adacel vaccines contain high copy numbers of B. pertussis DNA, which can be aerosolized, causing false-positive B. pertussis PCR results.

Investigating the impact of the definition of previous antibiotic exposure related to isolation of extended spectrum ß-lactamase-producing Klebsiella pneumoniae.

BACKGROUND: Previous antibiotic exposure is a risk factor for extended spectrum ß-lactamase (ESBL)-producing Klebsiella pneumoniae isolation, but the optimal definition of previous antibiotic exposure remains unclear. METHODS: This was a retrospective, case-control study comparing 88 patients with ESBL-producing K pneumoniae (cases) and 88 patients with non-ESBL-producing K pneumoniae (controls). Three previous antibiotic exposure definitions were analyzed, including durations of 30, 60, and 90 days prior to organism isolation. RESULTS: The mean cohort age was 63.6 ± 16.9 years, 43% were male, and 86% were black. In bivariate analysis, third-generation cephalosporins and cefepime were associated with ESBL-producing K pneumoniae isolation, and the odds ratios (OR) were significant regardless of previous antibiotic exposure definition. However, for fluoroquinolones and ampicillin/sulbactam, the ORs varied as a function of previous antibiotic exposure definition. In multivariate analysis, third-generation cephalosporin usage was a risk factor for ESBL-producing K pneumoniae isolation, whereas ampicillin/sulbactam usage was protective against these organisms, regardless of the time frame analyzed. Other independent predictors of ESBL-producing K pneumoniae included nursing home residence (OR, 9.30 [95% confidence interval: 3.69-23.43]) and hemodialysis (OR, 13.60 [95% confidence interval: 4.29-43.17]). CONCLUSION: Prior use of third-generation cephalosporins, nursing home residence, and hemodialysis were independent risk factors for isolation of an ESBL-producing K pneumoniae regardless of the time frame analyzed.

Sepsis associated with a new Atopobium species, provisionally named Atopobium detroiti: case report and review of the current status of the species Atopobium.

This paper reports a case of sepsis associated with a previously unknown Atopobium species and highlights the role of 16S ribosomal subunit sequencing in the rapid identification of slow-growing or atypical organisms in the clinical laboratory.

Methicillin-resistant Staphylococcus aureus infection with intermediate sensitivity to vancomycin: a case report and literature review.

Staphylococcus aureus is a major cause of bacteremia and endocarditis in adults. Vancomycin is the standard therapy for methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. Although clinical failure associated with the development of reduced susceptibility to vancomycin during the course of treatment for MRSA bacteremia has been reported infrequently, such an occurrence is very serious. We report a case of 43-year-old woman with of MRSA bacteremia, who relapsed after initial, apparently successful vancomycin treatment and developed left-sided endocarditis and vertebral osteomyelitis. Two weeks into her second admission, the vancomycin minimal inhibitory concentration rose from

Antibiotic pretreatment of hydrogel ureteral stent.

PURPOSE: To compare bacterial adhesion to hydrogel-coated and uncoated ureteral stents. The antimicrobial activity of coated and uncoated stents treated with commonly used antibiotic solutions also was evaluated. MATERIALS AND METHODS: Hydrogel coated and uncoated stent segments were dipped in different antibiotic solutions (ciprofloxacin, gentamicin, and cefazolin). Normal saline was used as the control. The segments were incubated in separate broths of Escherichia coli and Enterococcus faecalis to reach the log phase. They were sonicated to free the bacteria, and colony-forming units were determined after 48 hours. To evaluate antibacterial activity, hydrogel-coated and uncoated stent segments were dipped in the above-mentioned antibiotic solutions. Normal saline was used as the control. Segments were incubated in separate Mueller-Hinton agar plates inoculated with E. coli or Enterococcus faecalis, and the zones of inhibition were determined at 24 hours. The duration of antibacterial activity for each bacterium-antibiotic combination also was studied. RESULTS: Hydrogel coating did not significantly reduce bacterial adhesion. Zones of inhibition around stent pieces dipped in antibiotic solutions differed with the organism and the antibiotic. Cefazolin produced a significantly larger zone of inhibition with hydrogel-coated stent, but the duration of antibacterial activity was similar to that of uncoated stent. Hydrophilic coating significantly increased the duration of antibacterial activity of ciprofloxacin and gentamicin. CONCLUSION: Hydrogel coating on the surface of ureteral stents does not prevent or reduce bacterial adhesion. However, after antibiotic treatment, stents exhibit antibacterial activity in the local environment at greater intensity and for a longer time, depending on the bacterium-antibiotic combination.