What information can the lay public find about osteoporosis treatment? A descriptive study coding the content and quality of bisphosphonate information on the internet

Despite its effectiveness, bisphosphonate use for osteoporosis is low. We assessed bisphosphonate information on the internet and found the most commonly listed benefits/risks were bone density loss, gastrointestinal issues, and jaw necrosis, that risk quantification was rare, and information quality varied. Findings underscore the importance of clinical communication about bisphosphonates.

INTRODUCTION

The US Preventative Services Task Force recommends osteoporosis screening and treatment with bisphosphonates in high-risk populations. However, bisphosphonate use among individuals with osteoporosis remains low. The content and quality of information from outside sources may influence individuals' bisphosphonate decisions. Therefore, we sought to assess the content and quality of osteoporosis treatment information available to the public by conducting an internet search and coding available bisphosphonate information.

METHODS

Eleven search terms about osteoporosis and bisphosphonates were entered into four search engines. Two raters assessed websites for information about bisphosphonates, whether and how benefits and side effects were described and quantified, contraindications, and dosing instructions. Coders also assessed website interface and slant/balance of information.

RESULTS

One thousand four hundred seventy-three websites were identified. Two hundred twenty-seven websites met inclusion criteria and were coded. The most common bisphosphonate benefit described was prevention of bone density loss (77.1% of websites). The most common side effects described were gastrointestinal problems (66.1%) and jaw osteonecrosis (58.6%). Most websites did not quantify bisphosphonate benefits (78.0%) or side effects (82.4%). Complementary/integrative health websites (p < .001) and pharmaceutical litigation websites (p < .001) were more often slanted against taking bisphosphonates, compared to all websites coded. General medical knowledge websites were more balanced than other websites (p = .023).

CONCLUSIONS

The quality of bisphosphonate information on the internet varies substantially. Providers counseling patients about osteoporosis treatment should inquire about patients' baseline bisphosphonate knowledge. Providers can complement accurate information and address potential bisphosphonate misconceptions.

Central and peripheral line-associated bloodstream infections in Australian neonatal and paediatric intensive care units: findings from a comprehensive Victorian surveillance network, 2008-2016

BACKGROUND

Healthcare-associated infections in neonatal and paediatric populations are associated with poorer outcomes and healthcare costs, and surveillance is a necessary component of prevention programmes.

AIM

To evaluate burden of illness, aetiology, and time-trends for central and peripheral line-associated bloodstream infection (CLABSI and PLABSI) in Australian neonatal and paediatric intensive care units (ICUs) between July 1^st, 2008 and December 31^st, 2016.

METHODS

Using National Healthcare Safety Network methods, surveillance in neonatal and paediatric units was performed by hospitals participating in the Victorian Healthcare Associated Infection Surveillance System. Mixed effects Poisson regression was used to model infections over time.

FINDINGS

Overall, 82 paediatric CLABSI events were reported during 37,125 CVC-days (2.21 per 1000 CVC-days), 203 neonatal CLABSI events were reported during 92,169 CVC-days (2.20 per 1000 CVC-days), and 95 neonatal PLABSI events were reported during 142,240 peripheral line-days (0.67 per 1000 peripheral line-days). Over time, a significant decrease in quarterly risk for neonatal CLABSI events was observed (risk ratio (RR): 0.98; 95% confidence interval: 0.97-0.99; P = 0.023) and this reduction was significant for the 751-1000 g birth weight cohort (RR: 0.97; P = 0.015). Most frequently, coagulase-negative Staphylococcus spp. (24.2%) and Staphylococcus aureus (16.1%) were responsible for CLABSI events. A significant reduction in Gram-negative neonatal infections was observed (annual RR: 0.85; P < 0.001).

CONCLUSION

CLABSI rates in neonatal and paediatric ICUs in our region are low, and neonatal infections have significantly diminished over time. Evaluation of infection prevention programmes is required to determine whether specific strategies can be implemented to further reduce infection risk.

Validation of healthcare-associated infection surveillance in smaller Australian hospitals

A validation study was conducted in smaller (<100 acute beds) Victorian hospitals to evaluate case detection for Staphylococcus aureus bloodstream (SAB), meticillin-resistant S. aureus (MRSA) and vancomycin-resistant enterococci (VRE) infections. Overall, 142 infections were identified in 20 hospitals. For routine surveillance of SAB events, sensitivity was 74.4% and specificity was 100.0%. For MRSA infections, sensitivity was 47.5% and specificity was 90.9%. All confirmed VRE infections were reported correctly. Of unreported SAB and MRSA infections, 80% (N = 16) and 83.9% (N = 26) were community-associated infections, respectively. Future programme refinements include targeted education to ensure appropriate application of case definitions, particularly those including community onset.

A DNA vaccine for Crimean-Congo hemorrhagic fever protects against disease and death in two lethal mouse models

Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus capable of causing a severe hemorrhagic fever disease in humans. There are currently no licensed vaccines to prevent CCHFV-associated disease. We developed a DNA vaccine expressing the M-segment glycoprotein precursor gene of CCHFV and assessed its immunogenicity and protective efficacy in two lethal mouse models of disease: type I interferon receptor knockout (IFNAR^-/-) mice; and a novel transiently immune suppressed (IS) mouse model. Vaccination of mice by muscle electroporation of the M-segment DNA vaccine elicited strong antigen-specific humoral immune responses with neutralizing titers after three vaccinations in both IFNAR^-/- and IS mouse models. To compare the protective efficacy of the vaccine in the two models, groups of vaccinated mice (7–10 per group) were intraperitoneally (IP) challenged with a lethal dose of CCHFV strain IbAr 10200. Weight loss was markedly reduced in CCHFV DNA-vaccinated mice as compared to controls. Furthermore, whereas all vector-control vaccinated mice succumbed to disease by day 5, the DNA vaccine protected >60% of the animals from lethal disease. Mice from both models developed comparable levels of antibodies, but the IS mice had a more balanced Th1/Th2 response to vaccination. There were no statistical differences in the protective efficacies of the vaccine in the two models. Our results provide the first comparison of these two mouse models for assessing a vaccine against CCHFV and offer supportive data indicating that a DNA vaccine expressing the glycoprotein genes of CCHFV elicits protective immunity against CCHFV.

Crimean-Congo hemorrhagic Fever Virus (CCHFV) is a tick-borne virus capable of causing lethal human disease against which there are currently no approved vaccines. In this study, we compared the immunogenicity and protective efficacy of a candidate DNA vaccine expressing the glycoprotein precursor gene of CCHFV in two mouse models. In addition to the recently established IFNAR^-/- mouse pathogenesis model, we also tested the vaccine in a novel murine system in which the interferon (IFN) α/β signaling response of immunocompetent mice is transiently suppressed. We found that the DNA vaccine elicited high humoral immune responses and provided significant protection against challenge with CCHFV in both mouse models. These findings further our understanding of the requirements for a CCHFV vaccine and provide a new mouse model for the development of CCHFV countermeasures.

Epidemiology of Clostridium difficile infections in Australia: enhanced surveillance to evaluate time trends and severity of illness in Victoria, 2010-2014

BACKGROUND

With epidemic strains of Clostridium difficile posing a substantial healthcare burden internationally, there is a need for longitudinal evaluation of Clostridium difficile infection (CDI) events in Australia.

AIM

To evaluate time trends and severity of illness for CDI events in Australian healthcare facilities.

METHODS

All CDI events in patients admitted to Victorian public hospitals between 1(st) October 2010 and 31(st) December 2014 were reported to the Victorian Healthcare Associated Infection Surveillance System. CDI was defined as the isolation of a toxin-producing C. difficile organism in a diarrhoeal specimen, and classified as community-associated (CA-CDI) or healthcare-associated (HA-CDI). Severe disease was defined as admission to an intensive care unit, requirement for surgery and/or death due to infection. Time trends were examined using a mixed-effects Poisson regression model, and the Walter and Edward test of seasonality was applied to evaluate potential cyclical patterns.

FINDINGS

In total, 6736 CDI events were reported across 89 healthcare facilities. Of these, 4826 (71.6%) were HA-CDI, corresponding to a rate of 2.49/10,000 occupied bed days (OBDs). The incidence of HA-CDI was highest in the fifth quarter of surveillance (3.6/10,000 OBDs), followed by a reduction. Severe disease was reported in 1.66% of events, with the proportion being significantly higher for CA-CDI compared with HA-CDI (2.21 vs 1.45%, P = 0.03). The highest and lowest incidence of HA-CDI occurred in March and October, respectively.

CONCLUSIONS

A low incidence of HA-CDI was reported in Victoria compared with US/European surveillance reports. Seasonality was evident, together with diminishing HA-CDI rates in 2012-2014. Severe infections were more common in CA-CDI, supporting future enhanced surveillance in community settings.

Reporting Surgical Site Infections Following Primary and Revision Hip Arthroplasty— One Size Does Not Fit All

The risk of surgical site infection (SSI) is greater after revision hip arthroplasty than after primary procedures. While this is accepted as a clinical phenomenon, standardized surveillance strategies for healthcare-associated infections, including SSIs, do not currently take this into consideration. Most notably, the National Nosocomial Infections Surveillance (NNIS) risk index for stratification does not differentiate between primary and revision surgeries. Using data from a single US center, Leekha et al. recently demonstrated that the risk for SSI was almost twice as high after revision total hip arthroplasty when compared to primary total hip arthroplasty and that risk was even greater when deep incisional or organ/space infections were analyzed. The objective of this study was to compare SSI rates following primary and revision hip arthroplasty in a much larger Australian population to determine whether differences are accounted for by current risk indexing.

Interhospital Comparisons of Coronary Artery Bypass Graft Surgical Site Infection Rates Differ if Donor Sites Are Excluded

The advent of public reporting of hospital-acquired infection rates has sparked ongoing discussion about the most appropriate surveillance data to present. When we used different numerators to calculate rates of surgical site infection following coronary artery bypass graft surgery, we found that some hospitals' rates and their rankings were notably affected.

Implementation of standardised surveillance for Clostridium difficile infections in Australia: initial report from the Victorian Healthcare Associated Infection Surveillance System

Detection of a hypervirulent strain of Clostridium difficile in Victoria led to commencement of targeted surveillance for C. difficile infection in 2010. Cases were reported through the Victorian Healthcare Associated Infection Surveillance System. Between 1 October 2010 and 31 March 2011, 477 cases of C. difficile infection were identified; 11 (2.3%) secondary to a hypervirulent strain. Three hundred and seventy (1.7 per 10,000 occupied bed days) were healthcare associated. Data reflect successful implementation of continuous surveillance for C. difficile infection. With hypervirulent C. difficile infection now reported in other Australian states, development of a national data repository for C. difficile infection is necessary.

Novel plant-derived recombinant human interferons with broad spectrum antiviral activity

Type I interferons (IFNs) are potent mediators of the innate immune response to viral infection. IFNs released from infected cells bind to a receptor (IFNAR) on neighboring cells, triggering signaling cascades that limit further infection. Subtle variations in amino acids can alter IFNAR binding and signaling outcomes. We used a new gene crossbreeding method to generate hybrid, type I human IFNs with enhanced antiviral activity against four dissimilar, highly pathogenic viruses. Approximately 1400 novel IFN genes were expressed in plants, and the resultant IFN proteins were screened for antiviral activity. Comparing the gene sequences of a final set of 12 potent IFNs to those of parent genes revealed strong selection pressures at numerous amino acids. Using three-dimensional models based on a recently solved experimental structure of IFN bound to IFNAR, we show that many but not all of the amino acids that were highly selected for are predicted to improve receptor binding.

Immunogenicity and protective efficacy of a DNA vaccine against Venezuelan equine encephalitis virus aerosol challenge in nonhuman primates

A study to evaluate the immunogenicity and protective efficacy of a Venezuelan equine encephalitis virus (VEEV) DNA vaccine in an aerosol model of nonhuman primate infection was performed. Cynomolgus macaques vaccinated with a plasmid expressing the 26S structural genes of VEEV subtype IAB by particle-mediated epidermal delivery (PMED) developed virus-neutralizing antibodies. No serum viremia was detected in two out of three macaques vaccinated with the VEEV DNA after aerosol challenge with homologous virus, while one displayed a low viremia on a single day postchallenge. In contrast, all three macaques vaccinated with empty vector DNA developed a high viremia that persisted for at least 3 days after challenge. In addition, macaques vaccinated with the VEEV DNA had reduced febrile reactions, lymphopenia, and clinical signs of disease postchallenge as compared to negative control macaques. Therefore, although the sample size was small in this pilot study, these results indicate that a VEEV DNA vaccine administered by PMED can at least partially protect nonhuman primates against an aerosol VEEV challenge.

Directed molecular evolution improves the immunogenicity and protective efficacy of a Venezuelan equine encephalitis virus DNA vaccine

We employed directed molecular evolution to improve the cross-reactivity and immunogenicity of the Venezuelan equine encephalitis virus (VEEV) envelope glycoproteins. The DNA encoding the E1 and E2 proteins from VEEV subtypes IA/B and IE, Mucambo virus (MUCV), and eastern and western equine encephalitis viruses (EEEV and WEEV) were recombined in vitro to create libraries of chimeric genes expressing variant envelope proteins. ELISAs specific for all five parent viruses were used in high-throughput screening to identify those recombinant DNAs that demonstrated cross-reactivity to VEEV, MUCV, EEEV, and WEEV after administration as plasmid vaccines in mice. Selected variants were then used to vaccinate larger cohorts of mice and their sera were assayed by both ELISA and by plaque reduction neutralization test (PRNT). Representative variants from a library in which the E1 gene from VEEV IA/B was held constant and only the E2 genes of the five parent viruses were recombined elicited significantly increased neutralizing antibody titers to VEEV IA/B compared to the parent DNA vaccine and provided improved protection against aerosol VEEV IA/B challenge. Our results indicate that it is possible to improve the immunogenicity and protective efficacy of alphavirus DNA vaccines using directed molecular evolution.

Electronic antibiotic stewardship--reduced consumption of broad-spectrum antibiotics using a computerized antimicrobial approval system in a hospital setting

OBJECTIVES

Antibiotic stewardship is important, but the ideal strategy for providing stewardship in a hospital setting is unknown. A practical, sustainable and transferable strategy is needed. This study evaluates the impact of a novel computerized antimicrobial approval system on antibiotic-prescribing behaviour in a hospital. Effects on drug consumption, antibiotic resistance patterns of local bacteria and patient outcomes were monitored.

METHODS

The study was conducted at a tertiary referral teaching hospital in Melbourne, Australia. The system was deployed in January 2005 and guided the use of 28 restricted antimicrobials. Data were collected over 7 years: 5 years before and 2 years after deployment. Uptake of the system was evaluated using an in-built audit trail. Drug utilization was prospectively monitored using pharmacy data (as defined daily doses per 1000 bed-days) and analysed via time-series analysis with segmental linear regression. Antibiograms of local bacteria were prospectively evaluated. In-hospital mortality and length of stay for patients with Gram-negative bacteraemia were also reported.

RESULTS

Between 250 and 300 approvals were registered per month during 2006. The gradients in the use of third- and fourth-generation cephalosporins (+0.52, -0.05, -0.39; P < 0.01), glycopeptides (+0.27, -0.53; P = 0.09), carbapenems (+0.12, -0.24; P = 0.21), aminoglycosides (+0.15, -0.27; P < 0.01) and quinolones (+0.76, +0.11; P = 0.08) all fell after deployment, while extended-spectrum penicillin use increased. Trends in increased susceptibility of Staphylococcus aureus to methicillin and improved susceptibility of Pseudomonas spp. to many antibiotics were observed. No increase in adverse outcomes for patients with Gram-negative bacteraemia was observed.

CONCLUSIONS

The system was successfully adopted and significant changes in antimicrobial usage were demonstrated.

Compliance with surgical antibiotic prophylaxis--reporting from a statewide surveillance programme in Victoria, Australia

A statewide assessment of the compliance of surgical antibiotic prophylaxis (SAP) with guidelines was undertaken for large public hospitals in Victoria, Australia. This was carried out using data collected as part of a surveillance system for hospital-acquired infections. The study population comprised patients in Victorian public hospitals with >100 beds (N=27) undergoing cardiac surgical procedures, hip or knee arthroplasty, cholecystectomy, appendectomy, colon surgery or hysterectomy over a 21-month period. Australian guidelines recommend SAP for all 10 643 surgical procedures included in this study. Combining all procedures, 87% received SAP, the choice of antibiotic was concordant with guidelines for 53.3% of procedures, and the choice of antibiotic was considered to be 'adequate but not concordant' for 23.9% of procedures. SAP was considered to be inadequate for 18.9% of procedures. A large number of antibiotic regimens were utilized for cardiac and orthopaedic surgery. Documentation of timing of administration was not submitted for more than half of all procedures. Timing was concordant with guidelines for 76.4% of procedures when documented. Prophylactic antibiotic choice was generally more concordant with guidelines for cardiac and orthopaedic procedures than for other types of surgery. However, even for these procedures, where infections carry high morbidity, SAP was sometimes inadequate. Regular reporting on SAP compliance from data collected during surveillance for hospital-acquired infections is achievable. This should lead to improvements in both compliance and documentation.

Detection of biological threat agents by real-time PCR: comparison of assay performance on the R.A.P.I.D., the LightCycler, and the Smart Cycler platforms

BACKGROUND

Rapid detection of biological threat agents is critical for timely therapeutic administration. Fluorogenic PCR provides a rapid, sensitive, and specific tool for molecular identification of these agents. We compared the performance of assays for 7 biological threat agents on the Idaho Technology, Inc. R.A.P.I.D., the Roche LightCycler, and the Cepheid Smart Cycler.

METHODS

Real-time PCR primers and dual-labeled fluorogenic probes were designed to detect Bacillus anthracis, Brucella species, Clostridium botulinum, Coxiella burnetii, Francisella tularensis, Staphylococcus aureus, and Yersinia pestis. DNA amplification assays were optimized by use of Idaho Technology buffers and deoxynucleotide triphosphates supplemented with Invitrogen Platinum Taq DNA polymerase, and were subsequently tested for sensitivity and specificity on the R.A.P.I.D., the LightCycler, and the Smart Cycler.

RESULTS

Limit of detection experiments indicated that assay performance was comparable among the platforms tested. Exclusivity and inclusivity testing with a general bacterial nucleic acid cross-reactivity panel containing 60 DNAs and agent-specific panels containing nearest neighbors for the organisms of interest indicated that all assays were specific for their intended targets.

CONCLUSION

With minor supplementation, such as the addition of Smart Cycler Additive Reagent to the Idaho Technology buffers, assays for DNA templates from biological threat agents demonstrated similar performance, sensitivity, and specificity on all 3 platforms.

The efficacy of continuous infusion flucloxacillin in home therapy for serious staphylococcal infections and cellulitis

The efficacy and safety of continuous infusion flucloxacillin as home-based treatment was assessed in 62 consecutive patients with proven serious methicillin-susceptible Staphylococcus aureus (MSSA) infections (n = 36) and cellulitis (n = 26). The treatment was well tolerated and resulted in cure or adequate suppression of infection in 27 of 28 (96%) patients in the serious MSSA infection group, and in 24 of 26 (92%) patients in the cellulitis group.

Nosocomial infections in combined medical-surgical intensive care units in the United States

OBJECTIVE

To describe the epidemiology of nosocomial infections in combined medical-surgical (MS) intensive care units (ICUs) participating in the National Nosocomial Infection Surveillance (NNIS) System.

DESIGN

Analysis of surveillance data on 498,998 patients with 1,554,070 patient-days, collected between 1992 and 1998 from 205 MS ICUs following the NNIS Intensive Care Unit protocol, representing 152 participating NNIS hospitals in the United States.

RESULTS

Infections at three major sites represented 68% of all reported infections (nosocomial pneumonia, 31%; urinary tract infections (UTIs), 23%; and primary bloodstream infections (BSIs), 14%: 83% of episodes of nosocomial pneumonia were associated with mechanical ventilation, 97% of UTIs occurred in catheterized patients, and 87% of primary BSIs in patients with a central line. In patients with primary BSIs, coagulase-negative staphylococci (39%) were the most common pathogens reported; Staphylococcus aureus (12%) was as frequently reported as enterococci (11%). Coagulase-negative staphylococcal BSIs were increasingly reported over the 6 years, but no increase was seen in candidemia or enterococcal bacteremia. In patients with pneumonia, S. aureus (17%) was the most frequently reported isolate. Of reported isolates, 59% were gram-negative bacilli. In patients with UTIs, Escherichia coli (19%) was the most frequently reported isolate. Of reported isolates, 31% were fungi. In patients with surgical-site infections, Enterococcus (17%) was the single most frequently reported pathogen. Device-associated nosocomial infection rates for BSIs, pneumonia, and UTIs did not correlate with length of ICU stay, hospital bed size, number of beds in the ICU, or season. Combined MS ICUs in major teaching hospitals had higher device-associated infection rates compared to all other hospitals with combined medical-surgical units.

CONCLUSIONS

Nosocomial infections in MS ICUs at the most frequent infection sites (bloodstream, urinary, and respiratory tract) almost always were associated with use of an invasive device. Device-associated infection rates were the best available comparative rates between combined MS ICUs, but the distribution of device-associated rates should be stratified by a hospital's major teaching affiliation status.

Retinal structure and function in an animal model that replicates the biochemical hallmarks of desmosterolosis

Desmosterolosis is a rare, autosomal recessive, human disease characterized by multiple congenital anomalies in conjunction with grossly elevated levels of desmosterol and markedly reduced levels of cholesterol in all bodily tissues. Herein, we evaluated retinal sterol composition, histology, and electrophysiological function in an animal model that exhibited the biochemical features of desmosterolosis, produced by treating pregnant rats and their progeny with U18666A, an inhibitor of desmosterol reductase. Treated rats had cataracts, were substantially smaller, and had markedly high levels of desmosterol and profoundly low levels of cholesterol in their retinas and other tissues compared to age-matched controls. However, their retinas were histologically normal and electrophysiologically functional. These results suggest that desmosterol may be able to replace cholesterol in the retina, both structurally and functionally. These findings are discussed in the context of "sterol synergism".

Cholesterol synthesis in the vertebrate retina: effects of U18666A on rat retinal structure, photoreceptor membrane assembly, and sterol metabolism and composition

Treatment of neonatal rats with U18666A, an inhibitor of desmosterol delta24-reductase, results in accumulation of desmosterol (delta5,24) and depletion of cholesterol (delta5) in various bodily tissues and also causes cataracts. We evaluated the effects of U18666A on the sterol composition, de novo sterol synthesis, and histological structure of the retina. Neonatal Sprague-Dawley rats were injected subcutaneously with U18666A (15 mg/kg, in olive oil ) every other day from birth through 3 wk of age; in parallel, control rats received olive oil alone. At 21 d, treated and control groups each were subdivided into two groups: one group of each was injected intravitreally with [3H]acetate; retinas were removed 20 h later and nonsaponifiable lipids (NSL) were analyzed by radio-high-performance liquid chromatography. The other group was injected intravitreally with [3H]leucine; 4 d later, one eye of each animal was evaluated by light and electron microscopy and light microscopic autoradiography, while contralateral retinas and rod outer segment (ROS) membranes prepared therefrom were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis/fluorography. In the treated group, the delta5/delta5,24 mole ratio of retinas was ca. 1.0, and >88% of the NSL radioactivity was in delta5,24; in contrast, control retinas had delta5/delta5,24 >170, with >80% of the NSL radioactivity in delta5. Retinal histology, ultrastructure, ROS renewal rates, and rhodopsin synthesis and intracellular trafficking were comparable in both treated and control animals. These results suggest that desmosterol can either substitute functionally for cholesterol in the retina or it can complement subthreshold levels of cholesterol by sterol synergism.

Marked alteration of sterol metabolism and composition without compromising retinal development or function

PURPOSE

To evaluate the consequences of altering retinal sterol metabolism and composition on the development, histologic organization, and electrophysiological function of the retina, under conditions that mimic the biochemical hallmarks of the Smith-Lemli-Opitz (SLO) syndrome.

METHODS

Pregnant Sprague-Dawley rats were fed cholesterol-free chow containing AY9944 (treated group), an inhibitor of 3beta-hydroxysterol delta7-reductase, from gestational day 6 through postnatal day (P)28. Control animals were fed the same chow, but without AY9944. In addition, progeny in the treated group were injected subcutaneously every other day from birth to P28 with an olive oil emulsion containing AY9944; control animals received olive oil emulsion alone. At various postnatal times, tissues from treated and control animals were harvested, and their sterol profiles were analyzed by reversed-phase high-performance liquid chromatography. Companion eyes from animals of both groups were examined histologically at P1. At P28, animals were evaluated by electroretinography; tissues were then harvested for biochemical analysis and companion eyes were subjected to histologic and ultrastructural analyses.

RESULTS

Treatment of developing rats with AY9944 caused markedly abnormal accumulation of 7-dehydrosterols and severely reduced cholesterol levels in all tissues examined, relative to control animals. Despite this, treated animals exhibited normal retinal development and had no overt ocular defects or decrease in electroretinographic function, up to P28.

CONCLUSIONS

These results were unexpected, given the known biophysical effects of such sterol alterations on membrane properties and the profound dysmorphic and cognitive abnormalities associated with genetic defects in 3beta-hydroxysterol delta7-reductase that have been linked to the SLO syndrome. The results suggest that 7-dehydrosterols can substitute functionally for cholesterol in the retina or perhaps can act synergistically with subthreshold levels of residual cholesterol to allow normal cellular structure and function to be achieved.

Nosocomial infections in medical intensive care units in the United States. National Nosocomial Infections Surveillance System

OBJECTIVE

To describe the epidemiology of nosocomial infections in medical intensive care units (ICUs) in the United States.

DESIGN

Analysis of ICU surveillance data collected through the National Nosocomial Infections Surveillance (NNIS) System between 1992 and 1997.

SETTING

Medical ICUs in the United States.

PATIENTS

A total of 181,993 patients.

MEASUREMENTS AND MAIN RESULTS

Nosocomial infections were analyzed by infection site and pathogen distribution. Urinary tract infections were most frequent (31%), followed by pneumonia (27%) and primary bloodstream infections (19%). Eighty-seven percent of primary bloodstream infections were associated with central lines, 86% of nosocomial pneumonia was associated with mechanical ventilation, and 95% of urinary tract infections were associated with urinary catheters. Coagulase-negative staphylococci (36%) were the most common bloodstream infection isolates, followed by enterococci (16%) and Staphylococcus aureus (13%). Twelve percent of bloodstream isolates were fungi. The most frequent isolates from pneumonia were Gram-negative aerobic organisms (64%). Pseudomonas aeruginosa (21%) was the most frequently isolated of these. S. aureus (20%) was isolated with similar frequency. Candida albicans was the most common single pathogen isolated from urine and made up just over half of the fungal isolates. Fungal urinary infections were associated with asymptomatic funguria rather than symptomatic urinary tract infections (p < .0001). Certain pathogens were associated with device use: coagulase-negative staphylococci with central lines, P. aeruginosa and Acinetobacter species with ventilators, and fungal infections with urinary catheters. Patient nosocomial infection rates for the major sites correlated strongly with device use. Device exposure was controlled for by calculating device-associated infection rates for bloodstream infections, pneumonia, and urinary tract infections by dividing the number of device-associated infections by the number of days of device use. There was no association between these device-associated infection rates and number of hospital beds, number of ICU beds, or length of stay. There is a considerable variation within the distribution of each of these infection rates.

CONCLUSIONS

The distribution of sites of infection in medical ICUs differed from that previously reported in NNIS ICU surveillance studies, largely as a result of anticipated low rates of surgical site infections. Primary bloodstream infections, pneumonia, and urinary tract infections associated with invasive devices made up the great majority of nosocomial infections. Coagulase-negative staphylococci were more frequently associated with primary bloodstream infections than reported from NNIS ICUs of all types in the 1980s, and enterococci were a more frequent isolate from bloodstream infections than S. aureus. Fungal urinary tract infections, often asymptomatic and associated with catheter use, were considerably more frequent than previously reported. Invasive device-associated infections were associated with specific pathogens. Although device-associated site-specific infection rates are currently our most useful rates for performing comparisons between ICUs, the considerable variation in these rates between ICUs indicates the need for further risk adjustment.

Nosocomial infections in pediatric intensive care units in the United States. National Nosocomial Infections Surveillance System

OBJECTIVES

To describe the epidemiology of nosocomial infections in pediatric intensive care units (ICUs) in the United States.

BACKGROUND

Patient and ICU characteristics in pediatric ICUs suggest the pattern of nosocomial infections experienced may differ from that seen in adult ICUs.

METHODS

Data were collected between January 1992 and December 1997 from 61 pediatric ICUs in the United States using the standard surveillance protocols and nosocomial infection site definitions of the National Nosocomial Infections Surveillance System's ICU surveillance component.

RESULTS

Data on 110 709 patients with 6290 nosocomial infections were analyzed. Primary bloodstream infections (28%), pneumonia (21%), and urinary tract infections (15%) were most frequent and were almost always associated with use of an invasive device. Primary bloodstream infections and surgical site infections were reported more frequently in infants aged 2 months or less as compared with older children. Urinary tract infections were reported more frequently in children >5 years old compared with younger children. Coagulase-negative staphylococci (38%) were the most common bloodstream isolates, and aerobic Gram-negative bacilli were reported in 25% of primary bloodstream infections. Pseudomonas aeruginosa (22%) was the most common species reported from pneumonia and Escherichia coli (19%), from urinary tract infections. Enterobacter spp. were isolated with increasing frequency from pneumonia and were the most common Gram-negative isolates from bloodstream infections. Device-associated infection rates for bloodstream infections, pneumonia, and urinary tract infections did not correlate with length of stay, the number of hospital beds, or season.

CONCLUSIONS

In pediatric ICUs, bloodstream infections were the most common nosocomial infection. The distribution of infection sites and pathogens differed with age and from that reported from adult ICUs. Device-associated infection rates were the best rates currently available for comparisons between units, because they were not associated with length of stay, the number of beds in the hospital, or season.

Nosocomial infections in coronary care units in the United States. National Nosocomial Infections Surveillance System

To describe the epidemiology of nosocomial infections in Coronary Care Units (CCUs) in the United States, we analyzed data collected between 1992 and 1997 using the standard protocols of the National Nosocomial Infections Surveillance (NNIS) Intensive Care Unit (ICU) surveillance component. Data on 227,451 patients with 6,698 nosocomial infections were analyzed. Urinary tract infections (35%), pneumonia (24%), and primary bloodstream infections (17%) were almost always associated with use of an invasive device (93% with a urinary catheter, 82% with a ventilator, 82% with a central line, respectively). The distribution of pathogens differed from that reported from other types of ICUs. Staphylococcus aureus (21%) was the most common species reported from pneumonia and Escherichia coli (27%) from urine. Only 10% of reported urine isolates were Candida albicans. S. aureus (24%) was the more common bloodstream isolate than enterococci (10%). The mean overall patient infection rate was 2.7 infections per 100 patients. Device-associated infection rates for bloodstream infections, pneumonia, and urinary tract infections did not correlate with length of stay, number of hospital beds, number of CCU beds, or the hospital teaching affiliation, and were the best rates for comparisons between units. Use of invasive devices was lower than in other types of ICUs. Overall patient infection rates were lower than in other types of ICUs, which is largely explained by lower rates of invasive device usage.

In vitro metabolic competence of the frog retina: effects of glucose and oxygen deprivation

The metabolic competence and histological integrity of the frog retina in vitro were evaluated as a function of the presence/absence of exogenous glucose and of oxygen tension. Dark- and light-adapted frog neural retinas were incubated for 1-8 hr at 23 degrees C in a modified Ringer's-bicarbonate medium under aerobic and anaerobic conditions, in the presence and absence of 10 mM glucose. Control retinas (+glucose, aerobic conditions) maintained ATP levels comparable to those of freshly excised tissue (ave. 17 nmol mg protein-1), produced minimal lactate (ave. 0.12 mumol mg protein-1 hr-1), and exhibited normal histology. In the absence of any exogenous carbon source, retinas incubated aerobically maintained ATP levels, produced lactate, incorporated [3H]acetate into nonsaponifiable lipids, and exhibited histology comparable to controls. In the presence of 1 mM iodoacetate, aerobic ATP levels declined markedly, with or without exogenous glucose. Under anaerobic conditions with glucose present, lactate production increased ca. 8.5-fold, while ATP levels were maintained at control levels, demonstrating a marked Pasteur effect; under these conditions, retinas exhibited only moderate histopathological changes. However, in the absence of both glucose and oxygen, ATP levels declined precipitously, with concomitant massive cytological deterioration. No major differences in the biochemical measurements or histological appearance were observed as a function of light adaptation. These results demonstrate the remarkable resilience of the frog retina to anoxia and hypoglycemic stress. Aerobically, with or without exogenous glucose, ATP production and de novo lipid synthesis are maintained, apparently by recruitment of an endogenous carbohydrate substrate (e.g., glycogen).

Universal precautions: attitudes of Australian and New Zealand anaesthetists

OBJECTIVE

To survey the attitudes of a group of Australasian anaesthetists to the risks of bloodborne infections, and their understanding of Universal Precautions.

DESIGN

A questionnaire survey.

SETTING

A conference on health risks to anaesthetists in August 1995.

PARTICIPANTS

162 Australian and New Zealand anaesthetists.

RESULTS

Two-thirds of anaesthetists favoured preoperative HIV and hepatitis B and C testing; they rarely took "risk" histories from patients preoperatively. Only 37% always wore gloves while administering anaesthetics, and 67% reported they resheathed needles. Thirty-nine per cent had had needlestick injuries in the preceding 12 months; 43% did not always report them. The perceived needlestick accident rate was 1 in 1300 anaesthetics. Most (90%) were immunised against hepatitis B, but 20% of these had never had their serological response checked. Twelve per cent of anaesthetists had had occupational exposure to HIV. A high proportion of the anaesthetists understood the principles of Universal Precautions, but only half of them believed these to be practical.

CONCLUSIONS

The current situation of Australasian anaesthetists not complying with Universal Precautions and not taking a risk history for bloodborne pathogens may carry the greatest risk of accidental infection.

Radiation therapy for squamous cell carcinoma in dystrophic epidermolysis bullosa: case reports and literature review

Dystrophic epidermolysis bullosa (DEB) is a debilitating systemic disease frequently associated with biologically aggressive secondary squamous cell carcinomas arising from affected skin or mucosal surfaces. Treatment of these carcinomas with surgery, chemotherapy, or radiation is complicated by inherently poor wound healing. We report on two DEB patients treated with radiation therapy for locally advanced squamous cell carcinoma, and retrospectively analyze 10 DEB patients treated with radiation, reported in the literature. Of the 11 fully available and described case results from radiation therapy, six (54%) patients demonstrated a partial tumor response. All patients receiving > 4,500 cGy developed moist skin desquamation and delayed skin healing. Radiation therapy may be of benefit in palliating DEB patients who have locally advanced carcinoma, but has been associated with enhanced normal tissue toxicity, suggesting a narrow or absent therapeutic index between irradiated carcinoma and skin.

Skull osteomyelitis due to Salmonella species: two case reports and review

Osteomyelitis of the skull is a rare disease. We describe two cases due to Salmonella typhimurium and review 10 previously reported cases of salmonella osteomyelitis of the skull. This infection is frequently complicated by extradural abscess, which may be asymptomatic. Diagnostic imaging by means of computed tomographic scanning with contrast or gadolinium-enhanced magnetic resonance imaging should be performed to detect this complication. A good outcome can be expected with a combination of surgery and antibiotic therapy.

A comparison of quality and utilization problems in large and small group practices

Physicians practicing in large, multispecialty medical groups share an organizational culture that differs from that of physicians in small or independent practices. Since 1980, there has been a sharp increase in the size of multispecialty group practice organizations, in part because of increased efficiencies of large group practices. The greater number of physicians and support personnel in a large group practice also requires a relatively more sophisticated management structure. The efficiencies, conveniences, and management structure of a large group practice provide an optimal environment to practice medicine. However, a search of the literature found no data linking a large group practice environment to practice outcomes. The purpose of the study reported in this article was to determine if physicians in large practices have fewer quality and utilization problems than physicians in small or independent practices.

Cryptococcal disease of the CNS in immunocompetent hosts: influence of cryptococcal variety on clinical manifestations and outcome

We performed a retrospective review of cases of cerebral cryptococcosis among patients admitted to 12 Australian teaching hospitals between 1985 and 1992. Of 118 cases identified, 35 occurred in immunocompetent hosts. When cases due to Cryptococcus neoformans variety neoformans were compared with those due to Cryptococcus neoformans variety gattii, we found that the latter tended to occur in healthy hosts whose residence or job was located in a rural area, and cerebral mass lesions and/or hydrocephalus and pulmonary mass lesions were more common. For a subgroup of patients with infection due to C. neoformans variety gattii, multiple enhancing lesions were observed on cerebral computed tomograms, and papilledema, high CSF and serum cryptococcal antigen titers, and a worse prognosis (despite prolonged amphotericin B therapy and intraventricular shunt insertion) were also noted. No significant difference in clinical course or outcome in terms of variety of C. neoformans was noted for patients with cryptococcal meningitis whose computed tomographic scans appeared normal on presentation.

High-dose oral acyclovir reduces the incidence of cytomegalovirus infection in liver transplant recipients

To determine the impact of high-dose oral acyclovir on cytomegalovirus (CMV) infection or disease after liver transplantation, CMV cultures were prospectively collected for 6 months after transplantation. The incidence and timing of infection and disease in patients receiving high-dose oral acyclovir (3200 mg/day) from day 7 until 3 months after transplantation were compared with an historical control group who received no acyclovir. All patients who did not receive acyclovir (group 1, n = 12) but only 57% of those who did (group 2, n = 22) had CMV infection (P = .008). Nine (75%) group 1 but only 3 (14%) group 2 patients had positive leucocyte cultures (P = .0007). Three group 1 patients developed CMV disease; 1 group 2 patient developed CMV hepatitis. Each of these 4 patients had CMV viremia (P = .01). The frequency of CMV infection after liver transplantation appears to be reduced by high-dose oral acyclovir.

Autologous predonation, haemodilution and intraoperative blood salvage in elective abdominal aortic aneurysm repair

The feasibility of predonated autologous blood transfusion and intraoperative blood salvage in elective abdominal aortic aneurysm repair was studied. Twenty consecutive patients were evaluated, of whom five were excluded according to protocol criteria. Patients each donated 1 unit blood 14 and 7 days before operation. A third unit was withdrawn in the anaesthetic room and replaced with Hartmann's solution, producing a haemodiluted state. Intraoperative losses were minimized using the Haemonetics Cell Saver III Plus autotransfusion system. Predonated blood from two patients passed its expiry date owing to repeated operation postponements, leaving 13 patients for study. The mean(s.d.) intraoperative blood loss was 700(300) ml with a mean(s.d.) intraoperative salvage of 420(300) ml. Two patients were transfused intraoperative salvage of 420(300) ml. Two patients were transfused according to clinical need. Thus nine patients safely avoided homologous transfusion. With autologous predonation, haemodilution and intraoperative blood salvage, elective aortic aneurysm repair can be performed safely with minimal need for homologous blood.

Diphtheria: another risk of travel

A 19-year-old woman presented with cellulitis of her foot 10 days after returning from Bali. Swabs of a central necrotic area grew toxigenic Corynebacterium diphtheriae biotype gravis. The patient was treated with parenteral penicillin and made a complete recovery. Diphtheria immunisation should be regularly updated for travellers to the tropics. Clinical and laboratory recognition of this infection is essential for appropriate public health measures to be undertaken.