[show abstract][hide abstract] ABSTRACT: Management of prosthetic joint infections remain a clinical challenge, particularly infections due to methicillin resistant Staphylococci. Previously this infection has been considered a contraindication to debridement and retention strategies.
Antimicrobial Agents and Chemotherapy 10/2012; · 4.57 Impact Factor
[show abstract][hide abstract] ABSTRACT: Please cite this paper as: Mahony et al. Diagnosing swine flu: the inaccuracy of case definitions during the 2009 pandemic, an attempt at refinement, and the implications for future planning. Influenza and Other Respiratory Viruses DOI: 10.1111/j.1750-2659.2012.00398.x. Background At the onset of the pandemic H1N1/09 influenza A outbreak in Australia, health authorities devised official clinical case definitions to guide testing and access to antiviral therapy. Objectives To assess the diagnostic accuracy of these case definitions and to attempt to improve on them using a scoring system based on clinical findings at presentation. Patients/Methods This study is a retrospective case-control study across three metropolitan Melbourne hospitals and one associated community-based clinic during the influenza season, 2009. Patients presenting with influenza-like illness who were tested for H1N1/09 influenza A were administered a standard questionnaire of symptomatology, comorbidities, and risk factors. Patients with a positive test were compared to those with a negative test. Logistic regression was performed to examine for correlation of clinical features with disease. A scoring system was devised and compared with case definitions used during the pandemic. The main outcome measures were the positive and negative predictive values of our scoring system, based on real-life data, versus the mandated case definitions'. Results Both the devised scoring system and the case definitions gave similar positive predictive values (38-58% using ascending score groups, against 39-44% using the various case definitions). Negative predictive values were also closely matched (ranging from 94% to 73% in the respective score groups against 83-84% for the case definitions). Conclusions Accurate clinical diagnosis of H1N1/09 influenza A was difficult and not improved significantly by a structured scoring system. Investment in more widespread availability of rapid and sensitive diagnostic tests should be considered in future pandemic planning.
Influenza and Other Respiratory Viruses 06/2012; · 1.47 Impact Factor
[show abstract][hide abstract] ABSTRACT: Murray Valley encephalitis virus (MVEV) is a mosquito-borne virus that is found across Australia, Papua New Guinea and Irian Jaya. MVEV is endemic to northern Australia and causes occasional outbreaks across south-eastern Australia. 2011 saw a dramatic increase in MVEV activity in endemic regions and the re-emergence of MVEV in south-eastern Australia. This followed significant regional flooding and increased numbers of the main mosquito vector, Culex annulirostris, and was evident from the widespread seroconversion of sentinel chickens, fatalities among horses and several cases in humans, resulting in at least three deaths. The last major outbreak in Australia was in 1974, during which 58 cases were identified and the mortality rate was about 20%. With the potential for a further outbreak of MVEV in the 2011-2012 summer and following autumn, we highlight the importance of this disease, its clinical characteristics and radiological and laboratory features. We present a suspected but unproven case of MVEV infection to illustrate some of the challenges in clinical management. It remains difficult to establish an early diagnosis of MVEV infection, and there is a lack of proven therapeutic options.
The Medical journal of Australia 03/2012; 196(5):322-6. · 2.85 Impact Factor
[show abstract][hide abstract] ABSTRACT: To assess the secondary attack rates (SAR) and impact of the 2009 H1N1 epidemic in Melbourne, Victoria, Australia, and the measures implemented to control household transmission.
Patients with polymerase chain reaction-confirmed influenza A and pandemic H1N1 (pH1N1) were identified from hospital and microbiology laboratory records and asked to take part in a retrospective survey. Information obtained included: the constellation of symptoms, contact history, secondary infection, and household information, including adherence and attitudes towards quarantine measures.
The overall SAR of pH1N1 index patients was 30.6%, but a significantly lower SAR was noted with oseltamivir treatment (36.6% vs 22.8%, p < 0.05). The greatest reduction in SAR was observed when index patients aged 0-4 y received oseltamivir (83.3% vs 22.2%, p < 0.01). Quarantine was requested of 65.8% of patients and 92.8% self-reported adhering to recommendations. pH1N1 index patients, the number of median days bed-bound is 2.5 days, being unable or too sick to work for a median of 5.0 days, and lost a median of 7.0 days of work for reasons related to an influenza-like illness.
The pH1N1 influenza pandemic had a significant clinical impact on households. Public health interventions such as oseltamivir treatment of index cases were beneficial in reducing secondary attack rates, whilst quarantine measures were found to have high rates of self-reported compliance, understanding, and acceptability.
[show abstract][hide abstract] ABSTRACT: Information is required about treatment outcomes of Gram-negative prosthetic joint infections treated with prosthesis retention and surgical debridement, especially where biofilm-active antibiotics such as fluoroquinolones are used. The outcome of 17 consecutive patients with an early Gram-negative prosthetic joint infection who had been treated with prosthesis retention and surgical debridement was analysed. Enterobacteriaceae were isolated in 16 patients and infections were mixed with other organisms in 13 (76%) patients. The median joint age was 17 days and the median duration of symptoms before debridement was 7 days. All patients initially received intravenous β-lactam antibiotic therapy and 14 patients were then treated with oral ciprofloxacin. Treatment failure occurred in two patients over a median period of follow-up of 28 months. In only one patient was a relapsed Gram-negative infection responsible for the failure and this patient had not been treated with ciprofloxacin. The 2-year survival rate free of treatment failure was 94% (95% CI, 63-99%). Prosthesis retention with surgical debridement, in combination with antibiotic regimens including ciprofloxacin, was effective and should be considered for patients with early Gram-negative prosthetic joint infection.
Clinical Microbiology and Infection 06/2011; 17(6):862-7. · 4.58 Impact Factor
[show abstract][hide abstract] ABSTRACT: An Eritrean-born man observed over an extended period had upper gastrointestinal symptoms, fever, hepatosplenomegaly and pancytopenia in the setting of advanced HIV infection and poor adherence to antiretroviral therapy. Despite thorough investigation, it was not until a repeat gastroscopic examination and gastric biopsy were performed 18 months after initial presentation that Leishmania infection was diagnosed. The species was identified by polymerase chain reaction assay as L. donovani. Physicians managing HIV-infected patients from regions where Leishmania is endemic should consider visceral leishmaniasis, even in patients who have not lived in a Leishmania-endemic region for many years.
The Medical journal of Australia 04/2010; 192(8):474-5. · 2.85 Impact Factor
[show abstract][hide abstract] ABSTRACT: To describe the case characteristics and outcomes of patients hospitalised with pandemic (H1N1) 2009 influenza infection during the first 2 months of the epidemic.
Prospective case series of 112 patients admitted to seven hospitals in Melbourne with laboratory-confirmed pandemic (H1N1) 2009 influenza between 1 May and 17 July 2009.
Details of case characteristics, risk factors for severe disease, treatment and clinical course.
Of 112 hospitalised patients, most presented with cough (88%) and/or fever (82%), but several (4%) had neither symptom. A quarter of female patients (15) were pregnant or in the post-partum period. Patients presenting with multifocal changes on chest x-ray had significantly longer hospital lengths of stay, and were more likely to require intensive care unit admission. Thirty patients required admission to an intensive care unit, and three died during their acute illness. The median length of intensive care admission was 10.5 days (interquartile range, 5-16 days).
This study highlights risk factors for severe disease, particularly pregnancy. Clinical and public health planning for upcoming influenza seasons should take into account the spectrum and severity of clinical infection demonstrated in this report, and the need to concentrate resources effectively in high-risk patient groups.
The Medical journal of Australia 01/2010; 192(2):84-6. · 2.85 Impact Factor
[show abstract][hide abstract] ABSTRACT: We present the first six cases of H1N1 influenza 09 (confirmed by a polymerase chain reaction test from nasopharyngeal swabs) in patients requiring admission to intensive care in Australia (in three hospitals in the north-western suburbs of Melbourne). These cases highlight the small but significant risk of life-threatening respiratory failure associated with H1N1 influenza 09 infection.
The Medical journal of Australia 09/2009; 191(3):154-6. · 2.85 Impact Factor
[show abstract][hide abstract] ABSTRACT: For pandemic influenza planning, realistic estimates of personal protective equipment (PPE) and antiviral medication required for hospital healthcare workers (HCWs) are vital. In this simulation study, a patient with suspected avian or pandemic influenza (API) sought treatment at 9 Australian hospital emergency departments where patient-staff interactions during the first 6 hours of hospitalization were observed. Based on World Health Organization definitions and guidelines, the mean number of "close contacts" of the API patient was 12.3 (range 6-17; 85% HCWs); mean "exposures" were 19.3 (range 15-26). Overall, 20-25 PPE sets were required per patient, with variable HCW compliance for wearing these items (93% N95 masks, 77% gowns, 83% gloves, and 73% eye protection). Up to 41% of HCW close contacts would have qualified for postexposure antiviral prophylaxis. These data indicate that many current national stockpiles of PPE and antiviral medication are likely inadequate for a pandemic.
[show abstract][hide abstract] ABSTRACT: There is growing evidence of the efficacy of treating early staphylococcal infections of prosthetic joints with surgical debridement and prosthesis retention, combined with oral antibiotic regimens that include rifampicin in combination with a fluoroquinolone. With rising rates of fluoroquinolone-resistant staphylococci, evidence concerning the efficacy of alternative combinations of antibiotics is required. Twenty patients with staphylococcal prosthetic joint infections who had been treated with surgical debridement and prosthesis retention, and a combination of rifampicin and fusidic acid were analysed. The mean duration of symptoms before initial debridement was 16 (range 2-75) days. The median time of follow-up was 32 (range 6-76) months. Treatment failure occurred in two patients. The cumulative risk of treatment failure after 1 year was 11.76% (95% CI 3.08-39.40%). Two patients had their treatment changed because of nausea. Ten of 11 patients with infections involving methicillin-resistant Staphylococcus aureus had successful outcomes. Debridement without prosthesis removal, in combination with rifampicin and fusidic acid treatment, was effective and should be considered for patients with early staphylococcal prosthetic joint infections, including those with infections involving fluoroquinolone-resistant organisms.
Clinical Microbiology and Infection 07/2007; 13(6):586-91. · 4.58 Impact Factor