Epidemiology of Clostridium difficile infection in two tertiary-care hospitals in Perth, Western Australia: a cross-sectional study.

The epidemiology of Clostridium difficile infection (CDI) has changed over time and between countries. It is therefore essential to monitor the characteristics of patients at risk of infection and the circulating strains to recognize local and global trends, and improve patient management. From December 2011 to May 2012 we conducted a prospective, observational epidemiological study of patients with laboratory-confirmed CDI at two tertiary teaching hospitals in Perth, Western Australia to determine CDI incidence and risk factors in an Australian setting. The incidence of CDI varied from 5.2 to 8.1 cases/10 000 occupied bed days (OBDs) at one hospital and from 3.9 to 16.3/10 000 OBDs at the second hospital. In total, 80 patients with laboratory-confirmed CDI met eligibility criteria and consented to be in the study. More than half (53.8%) had hospital-onset disease, 28.8% had community-onset and healthcare facility-associated disease and 7.5% were community-associated infections according to the definitions used. Severe CDI was observed in 40.0% of these cases but the 30-day mortality rate for all cases was only 2.5%. Besides a shorter length of stay among cases of community-onset CDI, no characteristics were identified that were significantly associated with community-onset or severe CDI. From 70 isolates, 34 different ribotypes were identified. The predominant ribotypes were 014 (24.3%), 020 (5.7%), 056 (5.7%) and 070 (5.7%). Whereas this study suggests that the characteristics of CDI cases in Australia are not markedly different from those in other developed countries, the increase in CDI rate observed emphasizes the importance of surveillance.

Outbreak of invasive methicillin-resistant Staphylococcus aureus infection associated with acupuncture and joint injection.

OBJECTIVE: To describe an outbreak of invasive methicillin-resistant Staphylococcus aureus (MRSA) infection after percutaneous needle procedures (acupuncture and joint injection) performed by a single medical practitioner. SETTING: A medical practitioner's office and 4 hospitals in Perth, Western Australia. PATIENTS: Eight individuals who developed invasive MRSA infection after acupuncture or joint injection performed by the medical practitioner. METHODS: We performed a prospective and retrospective outbreak investigation, including MRSA colonization surveillance, environmental sampling for MRSA, and detailed molecular typing of MRSA isolates. We performed an infection control audit of the medical practitioner's premises and practices and administered MRSA decolonization therapy to the medical practitioner. RESULTS: Eight cases of invasive MRSA infection were identified. Seven cases occurred as a cluster in May 2004; another case (identified retrospectively) occurred approximately 15 months earlier in February 2003. The primary sites of infection were the neck, shoulder, lower back, and hip: 5 patients had septic arthritis and bursitis, and 3 had pyomyositis; 3 patients had bacteremia, including 1 patient with possible endocarditis. The medical practitioner was found to be colonized with the same MRSA clone [ST22-MRSA-IV (EMRSA-15)] at 2 time points: shortly after the first case of infection in March 2003 and again in May 2004. After the medical practitioner's premises and practices were audited and he himself received MRSA decolonization therapy, no further cases were identified. CONCLUSIONS: This outbreak most likely resulted from a breakdown in sterile technique during percutaneous needle procedures, resulting in the transmission of MRSA from the medical practitioner to the patients. This report demonstrates the importance of surveillance and molecular typing in the identification and control of outbreaks of MRSA infection.

Clostridium difficile-associated diarrhoea.

Clostridium difficile is an important nosocomial pathogen and the most frequently diagnosed cause of infectious hospital-acquired diarrhoea. Toxigenic strains usually produce toxin A and toxin B, which are the primary virulence factors of C. difficile. Some recently described strains produce an additional toxin, an adenosine-diphosphate ribosyltransferase known as binary toxin, the role of which in pathogenicity is unknown. There has been concern about the emergence of a hypervirulent fluoroquinolone-resistant strain of C. difficile in North America and Europe. The use of fluoroquinolone antimicrobials appears to be acting as a selective pressure in the emergence of this strain. In this review, we describe the current state of knowledge about C. difficile as a cause of diarrhoeal illness.

Case report: recovery from persistent septicemic melioidosis.

Septicemic melioidosis is often fatal despite treatment with antibiotics such as ceftazidime to which Burkholderia pseudomallei, the causal pathogen, is sensitive in vitro. We report a near-fatal case of septicemic melioidosis with persistent B. pseudomallei bacteremia despite intravenous ceftazidime in which combination therapy with meropenem and ciprofloxacin, splenectomy and correction of metabolic acidosis allowed for hospital discharge. The choice of antibiotic agents was supported by intracellular minimum inhibitory concentration analysis using B. pseudomallei co-culture in Acanthamoeba trophozoites. The patient's B. pseudomallei isolates were indistinguishable by pulsed-field gel electrophoresis from clinical and environmental isolates previously analyzed during investigation of a Western Australian melioidosis outbreak. A combination of antibiotics known to possess intracellular activity against B. pseudomallei, surgery and supportive critical care may provide a means of improving the probability of survival in persistent septicemic melioidosis.

Modification of general practitioner prescribing of antibiotics by use of a therapeutics adviser (academic detailer).

AIMS: This was a pilot study of the use of a clinical pharmacist as a therapeutics adviser (academic detailer) to modify antibiotic prescribing by general practitioners. METHODS: Following a visit by the adviser (March-May), 112 general practitioners were recruited and randomised to control or active groups. A panel of experts prepared a best practice chart of recommended drugs for upper and lower respiratory tract infections, otitis media and urinary tract infections. The adviser made a 10-15 min visit to each prescriber in the active group (June-July), gave them the chart and discussed its recommendations briefly. Doctors in the control group were not visited nor given the chart. Prescription numbers for all prescribers were obtained from the Commonwealth Health Insurance Commission for the pre(March-May) and postdetailing (August-September) periods using a three month lag time for data collection. Data for total numbers of prescriptions and for selected individual antibiotics used in these two periods were analysed using nonparametric statistics. RESULTS: Prescribing patterns were similar for the control and active groups in the predetailing period. For both groups, there were significant (P<0.03) increases (45% for control and 40% for active) in total number of antibiotic prescriptions in the post compared with the predetailing period. This trend was anticipated on the basis of the winter seasonal increase in respiratory infections. In line with the chart recommendations for first-line treatment, doctors in the active group prescribed significantly more amoxycillin (P<0.02) and doxycycline (P<0.001) in the post vs predetailing periods. By contrast, doctors in the control group prescribed significantly more cefaclor (P<0.03) and roxithromycin (P<0.03), drugs that were not recommended. The total cost of antibiotics prescribed by doctors in the control group increased by 48% ($37 150) from the preto postdetailing periods. In the same time period, the costs for the active group increased by only 35% ($21 020). CONCLUSIONS: We conclude that the academic detailing process was successful in modifying prescribing patterns and that it also decreased prescription numbers and costs. Application of the scheme on a nationwide basis could not only improve prescriber choice of the most appropriate antibiotic but also result in a significant saving of health care dollars.

Contamination of propofol infusions in the intensive care unit: incidence and clinical significance.

Epidemics of bacteraemia and wound infection have been associated with the infusion of bacterially contaminated propofol administered during anaesthesia. We conducted an observational study to determine the incidence and clinical significance of administration of potentially contaminated propofol to patients in an ICU setting. One hundred patients received a total of 302 infusions of propofol. Eighteen episodes of possible contamination of propofol syringes were identified, but in all cases contamination was by a low-grade virulence pathogen. There were no episodes of clinical infection or colonization which could be attributed to the administration of contaminated propofol. During the routine use of propofol to provide sedation in ICU patients the risk of nosocomial infection secondary to contamination of propofol is extremely low.

The management of common ocular infections.

Bacterial and viral infections involving the anterior segment of the eye and ocular adnexa present commonly in general practice, affecting patients of all ages. Careful assessment of the patient is necessary to distinguish between benign conditions and those with more serious complications. An understanding of the microbiology and pathogenesis of these conditions is helpful in rationalising current therapeutic approaches. This article focuses on the clinical presentation of common infections of the lids, conjunctiva and cornea, with a discussion of relevant therapeutic regimens for each condition.

Central venous catheters revisited--infection rates and an assessment of the new Fibrin Analysing System brush.

Sixty-one consecutive patients in the Intensive Care Unit requiring central venous lines (CVC) for five or more days were randomized to receive either a standard triple lumen CVC (STD/CVC) or a silver sulphadiazine and chlorhexidine impregnated CVC (SSD/CVC). Data from the 54 patients who completed the trial show a reduced infection rate (positive tip culture) in the SSD/CVC group (4 out of 28) compared to the STD/CVC group (10 out of 26) (P < 0.05). In addition, the new Fibrin Analysing System (FAS) brush was evaluated and used to determine the presence of infection in all the CVCs (STD/CVC and SSD/CVC combined, n = 54) at day 3 (i.e. early warning of CVC colonization/infection) and at the time of removal of the CVC. The FAS brush was able to detect an infected CVC on only one occasion on day 3 out of the 14 CVC tips which were later found to be colonized/infected at the time of removal. The sensitivity of the FAS brush in detecting colonized/infected CVCs at the time of CVC removal compared with CVC tip culture was 21% with a specificity of 100%. These findings would currently not support the routine use of the FAS brush in determining CVC infection/colonization.

Treatment of urinary tract infection. Clinical and economic considerations.

The epidemiology, clinical manifestations, natural history and management of urinary tract infection (UTI) are briefly reviewed as background to the economic considerations of diagnosis and treatment. Specific pharmacoeconomic analyses, such as cost-effectiveness and cost-benefit analyses, of UTI are not available. Analysis of the direct costs of diagnosis and treatment reveal that laboratory costs comprise the largest proportion, followed by physician consultation and pharmaceutical costs, respectively. Antimicrobial treatment has focused on acquisition cost without due regard to costs associated with method of delivery (especially with parenteral therapy), drug monitoring, complications, suboptimal therapy, drug wastage and waste disposal. These factors indicate a preference for ambulatory therapy using oral antimicrobials rather than institutional care using parenteral agents. Indirect costs, such as lost work time and quality-of-life factors, are not readily available. Evidence suggests that nosocomial UTIs add significantly to hospital costs. Studies citing the cost effectiveness of infection control programmes have often lacked detail and may have accrued benefits to the service without apportioning full costs. Future research directions include analysis of laboratory economics in relation to the clinical encounter, improved analysis of the utility and total costs of newer antimicrobials, quantifying home versus hospital treatment and improved costing of infection control programmes.

"Natural" therapy for infectious diseases.

Introduce the right kind of bacteria and several pathogens lose their niche in the human host--that's the rationale behind probiotic therapy. These and some other "natural" therapies are popular with patients and increasingly supported by research results.