High burden of complicated skin and soft tissue infections in the Indigenous population of Central Australia due to dominant Panton Valentine leucocidin clones ST93-MRSA and CC121-MSSA.

BACKGROUND: Superficial skin and soft tissue infections (SSTIs) are common among the Indigenous population of the desert regions of Central Australia. However, the overall burden of disease and molecular epidemiology of Staphylococcus aureus complicated SSTIs has yet to be described in this unique population. METHODS: Alice Springs Hospital (ASH) admission data was interrogated to establish the population incidence of SSTIs. A prospective observational study was conducted on a subset of S. aureus complicated SSTIs (carbuncles and furuncles requiring surgical intervention) presenting during a one month period to further characterize the clinical and molecular epidemiology. High resolution melting analysis was used for clonal complex discrimination. Real-time polymerase chain reaction identifying the lukF component of the Panton Valentine leucocidin (pvl) gene determined pvl status. Clinical and outcome data was obtained from the ASH medical and Northern Territory shared electronic health records. RESULTS: SSTIs represented 2.1% of ASH admissions during 2014. 82.6% occurred in Indigenous patients (n = 382) with an estimated incidence of 18.9 per 1, 000 people years compared to the non-Indigenous population of 2.9 per 1000, with an incident rate ratio of 6.6 (95% confidence interval 5.1-8.5). Clinical and molecular analysis was performed on 50 isolates from 47 patients. Community-associated methicillin-resistant S. aureus (CA-MRSA) predominated (57% of isolates). The high burden of SSTIs is partly explained by the prevalence of pvl positive strains of S. aureus (90% isolates) for both CA-MRSA and methicillin-susceptible S. aureus (MSSA). ST93-MRSA and CC121-MSSA were the most prevalent clones. SSTIs due to ST93-MRSA were more likely to require further debridement (p = 0.039), however they also more frequently received inactive antimicrobial therapy (p < 0.001). CONCLUSIONS: ST93-MRSA and CC121-MSSA are the dominant causes of carbuncles and furuncles in Central Australia. Both of these virulent clones harbor pvl but the impact on clinical outcomes remains uncertain. The high prevalence of CA-MRSA supports empiric vancomycin use in this population when antimicrobial therapy is indicated. Prompt surgical intervention remains the cornerstone of treatment.

Management of type 2 diabetes - a community partnership approach.

BACKGROUND: The impact of type 2 diabetes is severe in Aboriginal and Torres Strait Islander people. The Fitzroy Valley, a remote region of the Kimberley in Western Australia, has a high population of Indigenous Australians. An effective community partnership has been formed between the local hospital, the population health service and local health services. OBJECTIVE: This article describes the evaluation of a new model of partnership care using an audit cycle. Results Statistically significant improvements in foot examination, body mass index, urine albumin creatinine ratio, total cholesterol, triglycerides and visual acuity measurements were observed. Significant increases in the proportion of patients achieving cholesterol and triglycerides therapeutic targets occurred. Most other outcome indicators demonstrated a nonsignificant improvement, which may be due to the short time interval in the audit for potential change. CONCLUSION: A dedicated chronic disease team and a clinical information system to coordinate culturally appropriate, multidisciplinary chronic disease care enables effective management of chronic diseases such as type 2 diabetes.

Failure of medical therapy in pulmonary arterial hypertension. Is there an alternative diagnosis?

BACKGROUND: Despite the development of targeted therapies for pulmonary arterial hypertension (PAH), some patients fail to respond to medical therapy. There are a number of types of PAH, one of which is pulmonary venoocclusive disease (PVOD). Unlike other PAH types, the hallmark pathology of PVOD is fibrous occlusion of the small venules, potentially with arterial involvement. It was hypothesized that a lack of response to medical therapy in clinically diagnosed PAH can be explained by misdiagnosed PVOD. METHODS: This study reviewed cases of 14 patients with clinically diagnosed PAH who had failed to respond to medical therapy and had lung tissue available from autopsy or explant. Control samples (n = 6) were obtained from lungs explanted for other causes, and a previous transthoracic echocardiogram excluded pulmonary hypertension. Comprehensive vessel morphometry was performed, and the clinical data reviewed. RESULTS: Vessel analysis confirmed 86% of case patients had PVOD and 14% had arterial-only PAH (artPAH). In the PVOD case patients, significant pathology was present in all vessel types with similar obstructive, intimal fibrosis in the venules (p < 0.0001) and arterioles (p < 0.0001). This was considerably different from the intimal concentric laminar smooth muscle proliferation in the artPAH cases. There were no significant differences in clinical presentation between PVOD and artPAH case patients. Pulmonary edema was not observed in the PVOD cases. CONCLUSIONS: PVOD is an underdiagnosed and commonly misdiagnosed cause of pulmonary hypertension, which may present with a failure to respond to medical therapy. Further studies on PVOD may help confirm whether a change in its classification as a type of PAH is necessary.