A study of the microbiological profile of filler-induced skin necrosis.

Skin necrosis is one of the most severe complications following filler injections, and can result in permanent aesthetic defects. Although an increasing number of studies have addressed the management of dermal filler complications, no study has described the spectrum of microbial pathogens. The aim of this study was to delineate the bacterial profile and prognostic factors of filler-related skin necrosis by reviewing the clinical and microbiological features of these patients. A retrospective medical record review of patients undergoing treatment for skin necrosis induced by fillers was conducted. In total, 10 cases were identified, with injection sites being the nasolabial fold (70%; n = 7), nasal dorsum (20%; n = 2) and nasal tip (10%; n = 1). Reviewing the culture results, the true culture-positive rate was found to be 50% after cases of contamination were excluded. To avoid permanent sequelae, all physicians should be aware of possible secondary infections when treating filler-induced skin necrosis.

Use of cefovecin in dogs and cats attending first-opinion veterinary practices in Australia.

BACKGROUND: Cefovecin is a long-acting third-generation cephalosporin commonly used in veterinary medicine. Third-generation cephalosporins are critically important antimicrobials that should only be used after culture and susceptibility testing. The authors describe the common indications for cefovecin use in dogs and cats, and the frequency of culture and susceptibility testing. MATERIALS AND METHODS: A cross-sectional study was performed using clinical records extracted from VetCompass Australia. A previously described method was used to identify records containing cefovecin. The reason for cefovecin use was annotated in situ in each consultation text. RESULTS: Over a six-month period (February and September 2018), 5180 (0.4 per cent) consultations involved cefovecin administration, of which 151 were excluded. Cats were administered cefovecin more frequently than dogs (1.9 per cent of cat consultations and 0.1 per cent of dog consultations). The most common reasons for cefovecin administration to cats were cat fight injuries and abscesses (28 per cent) and dermatitis (13 per cent). For dogs, the most common reasons for cefovecin administration were surgical prophylaxis (24 per cent) and dermatitis (19 per cent). Culture and susceptibility testing were reported in 16 cases (0.3 per cent). CONCLUSION: Cefovecin is used in many scenarios in dogs and cats where antimicrobials may be either not indicated or where an antimicrobial of lower importance to human health is recommended.

Incidence and Trends of Infections with Pathogens Transmitted Commonly Through Food and the Effect of Increasing Use of Culture-Independent Diagnostic Tests on Surveillance - Foodborne Diseases Active Surveillance Network, 10 U.S. Sites, 2013-2016.

Foodborne diseases represent a substantial public health concern in the United States. CDC's Foodborne Diseases Active Surveillance Network (FoodNet) monitors cases reported from 10 U.S. sites* of laboratory-diagnosed infections caused by nine enteric pathogens commonly transmitted through food. This report describes preliminary surveillance data for 2016 on the nine pathogens and changes in incidences compared with 2013-2015. In 2016, FoodNet identified 24,029 infections, 5,512 hospitalizations, and 98 deaths caused by these pathogens. The use of culture-independent diagnostic tests (CIDTs) by clinical laboratories to detect enteric pathogens has been steadily increasing since FoodNet began surveying clinical laboratories in 2010 (1). CIDTs complicate the interpretation of FoodNet surveillance data because pathogen detection could be affected by changes in health care provider behaviors or laboratory testing practices (2). Health care providers might be more likely to order CIDTs because these tests are quicker and easier to use than traditional culture methods, a circumstance that could increase pathogen detection (3). Similarly, pathogen detection could also be increasing as clinical laboratories adopt DNA-based syndromic panels, which include pathogens not often included in routine stool culture (4,5). In addition, CIDTs do not yield isolates, which public health officials rely on to distinguish pathogen subtypes, determine antimicrobial resistance, monitor trends, and detect outbreaks. To obtain isolates for infections identified by CIDTs, laboratories must perform reflex culture†; if clinical laboratories do not, the burden of culturing falls to state public health laboratories, which might not be able to absorb that burden as the adoption of these tests increases (2). Strategies are needed to preserve access to bacterial isolates for further characterization and to determine the effect of changing trends in testing practices on surveillance.

Estimating Ten-Year Trends in Septic Shock Incidence and Mortality in United States Academic Medical Centers Using Clinical Data.

BACKGROUND: Reports that septic shock incidence is rising and mortality rates declining may be confounded by improving recognition of sepsis and changing coding practices. We compared trends in septic shock incidence and mortality in academic hospitals using clinical vs claims data. METHODS: We identified all patients with concurrent blood cultures, antibiotics, and vasopressors for ≥ two consecutive days, and all patients with International Classification of Diseases, 9th edition (ICD-9) codes for septic shock, at 27 academic hospitals from 2005 to 2014. We compared annual incidence and mortality trends. We reviewed 967 records from three hospitals to estimate the accuracy of each method. RESULTS: Of 6.5 million adult hospitalizations, 99,312 (1.5%) were flagged by clinical criteria, 82,350 (1.3%) by ICD-9 codes, and 44,651 (0.7%) by both. Sensitivity for clinical criteria was higher than claims (74.8% vs 48.3%; P < .01), whereas positive predictive value was comparable (83% vs 89%; P = .23). Septic shock incidence, based on clinical criteria, rose from 12.8 to 18.6 cases per 1,000 hospitalizations (average, 4.9% increase/y; 95% CI, 4.0%-5.9%), while mortality declined from 54.9% to 50.7% (average, 0.6% decline/y; 95% CI, 0.4%-0.8%). In contrast, septic shock incidence, based on ICD-9 codes, increased from 6.7 to 19.3 per 1,000 hospitalizations (19.8% increase/y; 95% CI, 16.6%-20.9%), while mortality decreased from 48.3% to 39.3% (1.2% decline/y; 95% CI, 0.9%-1.6%). CONCLUSIONS: A clinical surveillance definition based on concurrent vasopressors, blood cultures, and antibiotics accurately identifies septic shock hospitalizations and suggests that the incidence of patients receiving treatment for septic shock has risen and mortality rates have fallen, but less dramatically than estimated on the basis of ICD-9 codes.

Sending repeat cultures: is there a role in the management of bacteremic episodes? (SCRIBE study).

BACKGROUND: In the management of bacteremia, positive repeat blood cultures (persistent bacteremia) are associated with increased mortality. However, blood cultures are costly and it is likely unnecessary to repeat them for many patients. We assessed predictors of persistent bacteremia that should prompt repeat blood cultures. METHODS: We conducted a retrospective cohort study of bacteremias at an academic hospital from April 2010 to June 2014. We examined variables associated with patients undergoing repeat blood cultures, and with repeat cultures being positive. A nested case control analysis was performed on a subset of patients with repeat cultures. RESULTS: Among 1801 index bacteremias, repeat cultures were drawn for 701 patients (38.9 %), and 118 persistent bacteremias (6.6 %) were detected. Endovascular source (adjusted odds ratio [aOR], 7.66; 95 % confidence interval [CI], 2.30-25.48), epidural source (aOR, 26.99; 95 % CI, 1.91-391.08), and Staphylococcus aureus bacteremia (aOR, 4.49; 95 % CI, 1.88-10.73) were independently associated with persistent bacteremia. Escherichia coli (5.1 %, P = 0.006), viridans group (1.7 %, P = 0.035) and ß-hemolytic streptococci (0 %, P = 0.028) were associated with a lower likelihood of persistent bacteremia. Patients with persistent bacteremia were less likely to have achieved source control within 48 h of the index event (29.7 % vs 52.5 %, P < .001), but after variable reduction, source control was not retained in the final multivariable model. CONCLUSIONS: Patients with S. aureus bacteremia or endovascular infection are at risk of persistent bacteremia. Achieving source control within 48 h of the index bacteremia may help clear the infection. Repeat cultures after 48 h are low yield for most Gram-negative and streptococcal bacteremias.

Infection with Pathogens Transmitted Commonly Through Food and the Effect of Increasing Use of Culture-Independent Diagnostic Tests on Surveillance--Foodborne Diseases Active Surveillance Network, 10 U.S. Sites, 2012-2015.

To evaluate progress toward prevention of enteric and foodborne illnesses in the United States, the Foodborne Diseases Active Surveillance Network (FoodNet) monitors the incidence of laboratory-confirmed infections caused by nine pathogens transmitted commonly through food in 10 U.S. sites. This report summarizes preliminary 2015 data and describes trends since 2012. In 2015, FoodNet reported 20,107 confirmed cases (defined as culture-confirmed bacterial infections and laboratory-confirmed parasitic infections), 4,531 hospitalizations, and 77 deaths. FoodNet also received reports of 3,112 positive culture-independent diagnostic tests (CIDTs) without culture-confirmation, a number that has markedly increased since 2012. Diagnostic testing practices for enteric pathogens are rapidly moving away from culture-based methods. The continued shift from culture-based methods to CIDTs that do not produce the isolates needed to distinguish between strains and subtypes affects the interpretation of public health surveillance data and ability to monitor progress toward prevention efforts. Expanded case definitions and strategies for obtaining bacterial isolates are crucial during this transition period.

Descriptive, Longitudinal Study Results Applied to Statistical Models to Assess the Impact of Early Microbiological Cultures on the Economic Burden of Treatment for Infected Diabetic Foot Ulcers at a Mexican Public Health Facility.

Infection plays a critical role in health care and impacts the cost of the treatment of diabetic foot ulcers (DFU). To examine the cost reduction associated with the multidisciplinary treatment of infected DFU (IDFU) by obtaining early (ie, within 48 hours of admission) microbiological culture results, a descriptive, longitudinal study was conducted. Data were collected prospectively from patient medical charts of a cohort of 67 patients (mean age, 56.14 ± 12.3 years; mean duration of diabetes, 14.95 ± 8 years) with IDFU treated at a Mexican public health facility from January 1 to April 30, 2010. Information included demographic data (age, gender, marital status, time elapsed since first diagnosis of diabetes mellitus type 2 [DM2]), and the following clinical records: Wagner classification, bacterium type, antimicrobial resistance, length of hospital stay, and the antibiotic schedule utilized, as well as number and type of laboratory tests, medications, intravenous therapy, surgical and supportive treatment, type and number of specialists, and clinical outcome. Microcosting was used to calculate the unit cost of each medical treatment element. Using the Monte Carlo and Markov predictive simulation economical models, cost reduction associated with early identification of the specific microorganism through bacterial culture in IDFU was estimated. Based on the statistical results, differences between real and estimated costs when including early microbiological culture were identified and the number and type of most common species of infectious bacteria were detected. The total cost observed in the patient cohort was $502 438.04 USD, mean cost per patient was $7177.69 ± $5043.51 USD, and 72.75% of the total cost was associated with the hospital stay length. The cost of the entire treatment including antibiotics was $359 196.16 USD; based on the simulation of early microbiological culture, the model results showed cost could be reduced by 10% to 25% (in this study, the cost could be as low as $304 624.63 USD). The use of early microbiological cultures on IDFU to determine the appropriate antibiotic can reduce treatment costs by >30% if hospital stay is part of the consideration.

Assessing the Utility of Urine Testing in Febrile Infants Aged 2 to 12 Months With Bronchiolitis.

OBJECTIVES: The aims of the study were to investigate whether the prevalence of urinary tract infections (UTIs) in febrile infants aged 2 to 12 months with bronchiolitis is higher than the presumed prevalence of asymptomatic bacteriuria (1%) in similarly aged patients and thus to determine whether UTI testing is necessary for these patients. METHODS: This was a prospective cohort study in which we enrolled a convenience sample of febrile infants aged 2 to 12 months with a clinical diagnosis of bronchiolitis. All patients were seen in the emergency department at a large children's hospital between November 1, 2011 and April 15, 2012, had reported or documented fever higher than 38°C, and had urine collected for determination of the presence of UTI. After the conclusion of enrollment, a chart review was conducted to assess missed cases. RESULTS: Positive urine cultures were found in 6/90 (6.7%) patients (confidence interval, 2.5%-13.9%). The positive urine cultures and urinalysis results were found in 4/90 (4.5%) patients (confidence interval, 1.2%-11%). CONCLUSIONS: In our patient population, a significant proportion of infants aged 2 to 12 months who present with bronchiolitis and fever have a concurrent UTI. Obtaining a urine specimen for UTI testing should be considered in infants aged 2 to 12 months with bronchiolitis and fever. A larger multicenter study is needed to further assess the risk factors for UTIs in this patient population.

Bacterial enteric infections detected by culture-independent diagnostic tests--FoodNet, United States, 2012-2014.

The increased availability and rapid adoption of culture-independent diagnostic tests (CIDTs) is moving clinical detection of bacterial enteric infections away from culture-based methods. These new tests do not yield isolates that are currently needed for further tests to distinguish among strains or subtypes of Salmonella, Campylobacter, Shiga toxin-producing Escherichia coli, and other organisms. Public health surveillance relies on this detailed characterization of isolates to monitor trends and rapidly detect outbreaks; consequently, the increased use of CIDTs makes prevention and control of these infections more difficult. During 2012-2013, the Foodborne Diseases Active Surveillance Network (FoodNet*) identified a total of 38,666 culture-confirmed cases and positive CIDT reports of Campylobacter, Salmonella, Shigella, Shiga toxin-producing E. coli, Vibrio, and Yersinia. Among the 5,614 positive CIDT reports, 2,595 (46%) were not confirmed by culture. In addition, a 2014 survey of clinical laboratories serving the FoodNet surveillance area indicated that use of CIDTs by the laboratories varied by pathogen; only CIDT methods were used most often for detection of Campylobacter (10%) and STEC (19%). Maintaining surveillance of bacterial enteric infections in this period of transition will require enhanced surveillance methods and strategies for obtaining bacterial isolates.

Implementing a urinary tract infection clinical practice guideline in an ambulatory urgent care practice.

A clinical practice guideline for uncomplicated urinary tract infections in an ambulatory urgent care practice was implemented. Aims were to increase the number of first-line antibiotics prescribed to treat uncomplicated urinary tract infections, increase the use of second-line antibiotics prescribed when appropriate, and decrease the number of unnecessary urine cultures.

Independent influence of negative blood cultures and bloodstream infections on in-hospital mortality.

BACKGROUND: The independent influence of blood culture testing and bloodstream infection (BSI) on hospital mortality is unclear. METHODS: We included all adults treated in non-psychiatric services at our hospital between 2004 and 2011. We identified all blood cultures and their results to determine the independent association of blood culture testing and BSI on death in hospital using proportional hazards modeling that adjusted for important covariates. RESULTS: Of 297 070 hospitalizations, 48 423 had negative blood cultures and 5274 had BSI. 12 529 (4.2%) died in hospital. Compared to those without blood cultures, culture-negative patients and those with BSI were sicker. Culture-negative patients had a significantly increased risk of death in hospital (adjusted hazard ratio [HR] ranging between 3.1 and 4.4 depending on admission urgency, extent of comorbidities, and whether the blood culture was taken in the intensive care unit). Patients with BSI had a significantly increased risk of death (adj-HR ranging between 3.8 and 24.3] that was significantly higher when BSI was: diagnosed within the first hospital day; polymicrobial; in patients who were exposed to immunosuppressants or were neutropenic; or due to Clostridial and Candidal organisms. Death risk in culture negative and bloodstream infection patients decreased significantly with time. CONCLUSIONS: Risk of death in hospital is independently increased both in patients with negative blood cultures and further in those with bloodstream infection. Death risk associated with bloodstream infections varied by the patient's immune status and the causative microorganism.

Response surface optimization of medium components for naringinase production from Staphylococcus xylosus MAK2.

Response surface methodology was used to optimize the fermentation medium for enhancing naringinase production by Staphylococcus xylosus. The first step of this process involved the individual adjustment and optimization of various medium components at shake flask level. Sources of carbon (sucrose) and nitrogen (sodium nitrate), as well as an inducer (naringin) and pH levels were all found to be the important factors significantly affecting naringinase production. In the second step, a 22 full factorial central composite design was applied to determine the optimal levels of each of the significant variables. A second-order polynomial was derived by multiple regression analysis on the experimental data. Using this methodology, the optimum values for the critical components were obtained as follows: sucrose, 10.0%; sodium nitrate, 10.0%; pH 5.6; biomass concentration, 1.58%; and naringin, 0.50% (w/v), respectively. Under optimal conditions, the experimental naringinase production was 8.45 U/mL. The determination coefficients (R(2)) were 0.9908 and 0.9950 for naringinase activity and biomass production, respectively, indicating an adequate degree of reliability in the model.

The application of Poisson units to the determination of median lethal cell culture dose.

The median lethal cell culture dose (CCLD(50)) and its 95% confidence interval were determined using the Behrens and Kärber area method with subsequent regression analysis by the action of methylmercury iodide (CH(3)HgI; MMI) on monolayer cultures of HeLa cells. The concentrations of MMI were 0.45, 0.9, 1.8, 3.65, 7.3 and 14.6 microM/l. The duration of MMI action was 24 h. All the calculations were performed with means of sample cell numbers derived from Poisson units. The basis for deriving the Poisson units is the Poisson distribution property on the equality mean to variance or, which is the same, on the equality standard deviation to the root square of mean. Because the size of Poisson unit is predetermined, it is a simple task to find the mean. The outcome of any single count of discrete random objects in the definite area or time interval is divided by the number of Poisson units. The Poisson unit for counting cultured cells was derived by us in relation to Gorjaev's net. In this case it is appropriate to count the cells on the square equal to two Gorjaev's nets. The corresponding Poisson unit is equal to 1/5 of Gorjaev's net (45 big squares). Near-coincidence of CCLD(50) as well as its 95% confidence intervals by use of logarithmic and linear models was observed. However, the former approach was better than the second. CCLD(50) and its 95% confidence interval values, obtained with the aid of the logarithmic model in three series of experiments, were 2.56+/-0.33, 2.09+/-0.37 and 2.31+/-0.37 microM/l.

Relevance and utility of peritoneal cultures in patients with peritonitis.

BACKGROUND: The pathogenic organisms responsible for the manifestations of secondary peritonitis have been well characterized through almost 30 years of experimental and clinical studies. Enteric gram-negative organisms and anaerobes predominate, with Escherichia coli and Bacteroides fragilis, respectively, being the most frequent isolates. This flora is remarkably consistent across patients and institutions. As a result of this consistency and the availability of well-established effective empiric antimicrobial regimens, many surgeons believe that cultures of peritoneal exudates in patients with peritonitis offer no useful information and no clinical benefit. METHODS: Review of pertinent antibiotic and management trials in the management of intraabdominal infection. RESULTS: There is increasing evidence that identification of organisms resistant to the chosen empiric antibiotic regimen portends a higher likelihood of failure. What is not clear is whether postoperative changes in the regimen in accordance with sensitivity patterns of the isolates offers any clinical advantage. In most circumstances, the data provided allow for simplification of the antibiotic regimen. CONCLUSION: The potential for reducing antibiotic exposure and the value of information derived from surveillance of microbial sensitivity patterns support the routine performance of peritoneal cultures.

Rapid antigen detection assay for identification of Chlamydia trachomatis infection.

A rapid antigen detection test was compared with direct fluorescent-antibody staining and with tissue culture isolation for the detection of Chlamydia trachomatis infections in 507 women. The sensitivities observed were 75, 76, and 84%, respectively, with specificities of > 99%.

Spatial distribution of neurons in tissue culture wells: implications for sampling methods to estimate population size.

Many laboratory procedures require the counting of cells in culture. While many cultured cells may be counted by automated methods, neuronal cultures often require manual cell counting methods that are prohibitively time-consuming. This paper examines methods of sampling from tissue culture wells for estimating total cell counts. Performance of sampling and estimation schemes will depend in part on how the cells distribute themselves within a well. Spatial statistical analysis techniques are applied to the known total number and distribution of neurons in two wells counted in a grid scheme to demonstrate some important features of the neuron distributional patterns. Based on these two wells and simulated realizations from other point processes, a new sampling and estimation technique using open wedge-shaped sampling regions radiating from the centre of the well is proposed. This method is shown to result in more accurate estimates of the total number of neurons in the well than standard methods.