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.

The spotted traveller.

A 23 year old university student comes to see you with a febrile illness and a rash. She has just returned from a 6 week holiday in South East Asia having visited Thailand, Vietnam, Hong Kong and the Philippines. Prior to going away she went to a travel clinic, was appropriately immunised and given malaria prophylaxis which she has taken assiduously. Her symptoms have been present for about 3 days and consist of severe retro-orbital headache, diffuse myalgias, fevers and chills, and anorexia. The rash appeared the day before on her trunk and is now beginning to involve her arms with a slight papular element. She also has conjunctival haemorrhages and is febrile with a temperature of 38.9 degrees C. A full blood count done urgently does not show any malaria parasites but does reveal a low platelet count of 85,000 x 10(6)/L.

Fusidic acid in other infections.

Fusidic acid, both systemic and topical, has been used for a wide variety of less common infections. Efficacy for oral fusidic acid has been demonstrated in the treatment of Clostridium difficile colitis and in staphylococcal infections in patients with cystic fibrosis. Topical fusidic acid gel is also effective in bacterial conjunctivitis and other minor external eye infections, and may be effective in reducing bacterial flora in the conjunctival sac prior to eye surgery. Studies suggest a potential role for fusidic acid in neurosurgical prophylaxis, as adjunctive therapy in bacterial endophthalmitis and Legionella pneumonia, and in leprosy. Topical fusidic acid has no effect in the treatment of chlamydial conjunctivitis or the prevention of staphylococcal infections in patients on continuous ambulatory peritoneal dialysis.

Non-toxigenic Corynebacterium diphtheriae: two cases and review of the literature.

Non-toxigenic Corynebacterium diphtheriae infections are being reported with increasing frequency. We present two cases of C. diphtheriae endocarditis requiring early valve replacement. Both cases were complicated by cerebral embolic phenomena and pseudoaneurysm formation in lower limb arterial vessels. Non-toxigenic C. diphtheriae septicaemia must be excluded when 'diphtheroids' are isolated from blood cultures.