Adjunctive intravenous then oral vitamin C for moderate and severe community-acquired pneumonia in hospitalized adults: feasibility of randomized controlled trial.

Patients hospitalised with community acquired pneumonia (CAP) have low peripheral blood vitamin C concentrations and limited antioxidant capacity. The feasibility of a trial of vitamin C supplementation to improve patient outcomes was assessed. Participants with moderate and severe CAP (CURB-65 ≥ 2) on intravenous antimicrobial treatment were randomised to either intravenous vitamin C (2.5 g 8 hourly) or placebo before switching to oral intervention (1 g tds) for 7 days when they were prescribed oral antimicrobial therapy. Of 344 patients screened 75 (22%) were randomised and analysed. The median age was 76 years, and 43 (57%) were male. In each group, one serious adverse event that was potentially intervention related occurred, and one subject discontinued treatment. Vitamin C concentrations were 226 µmol/L in the vitamin C group and 19 µmol/L in the placebo group (p < 0.001) after 3 intravneous doses. There were no signficant differences between the vitamin C and placebo groups for death within 28 days (0 vs. 2; p = 0.49), median length of stay (69 vs. 121 h; p = 0.07), time to clinical stability (22 vs. 49 h; p = 0.08), or readmission within 30 days (1 vs. 4; p = 0.22). The vitamin C doses given were safe, well tolerated and saturating. A randomised controlled trial to assess the efficacy of vitamin C in patients with CAP would require 932 participants (CURB-65 ≥ 2) to observe a difference in mortality and 200 participants to observe a difference with a composite endpoint such as mortality plus discharge after 7 days in hospital. These studies are feasible in a multicentre setting.

Safety and clinical outcomes of outpatient parenteral antibiotic therapy for infective endocarditis in Christchurch, New Zealand: A retrospective cohort study.

OBJECTIVES: We examined the safety and clinical outcomes of outpatient parenteral antibiotic therapy (OPAT) for patients with infective endocarditis (IE) in Christchurch, New Zealand. METHODS: Demographic and clinical data were collected from all adult patients treated for IE over 5 years. Outcomes were stratified by receipt of at least partial OPAT vs entirely hospital-based parenteral therapy. RESULTS: There were 172 episodes of IE between 2014 and 2018. OPAT was administered in 115 cases (67%) for a median of 27 days after a median of 12 days of inpatient treatment. In the OPAT cohort, viridans group streptococci were the commonest causative pathogens (35%) followed by Staphylococcus aureus (25%) and Enterococcus faecalis (11%). There were six (5%) antibiotic-related adverse events and 26 (23%) readmissions in the OPAT treatment group. Mortality in OPAT patients was 6% (7/115) at 6 months and 10% (11/114) at 1 year and for patients receiving wholly inpatient parenteral therapy was 56% (31/56) and 58% (33/56), respectively. Three patients (3%) in the OPAT group had a relapse of IE during the 1-year follow-up period. CONCLUSION: OPAT can be used safely in patients with IE, even in selected cases with complicated or difficult-to-treat infections.

Success of Debridement, Antibiotics, and Implant Retention in Prosthetic Joint Infection Following Primary Total Knee Arthroplasty: Results From a Prospective Multicenter Study of 189 Cases.

BACKGROUND: This study aimed to identify the success rate of debridement, antibiotics, and implant retention (DAIR) for prosthetic joint infection (PJI) in a large prospective cohort of patients undergoing total knee arthroplasty (TKA). The ability for different PJI classification systems to predict success was assessed. METHODS: Prospective data recorded in the Prosthetic Joint Infection in Australia and New Zealand Observational study were analyzed. One hundred eighty-nine newly diagnosed knee PJIs were managed with DAIR between July 2014 and December 2017. Patients were prospectively followed up for 2 years. A strict definition of success was used, requiring the patient being alive with documented absence of infection, no ongoing antibiotics and the index prosthesis in place. Success was compared against the Coventry (early PJI ≤1 month), International Consensus Meeting (early ≤90 days), Auckland (early <1 year), and Tsukayama (early ≤1 month, hematogenous >1 month with <7 days symptoms, chronic >1 month with >7 days symptoms) classifications. RESULTS: DAIR success was 45% (85/189) and was highest in early PJIs defined according to the Coventry (adjusted odds ratio [aOR] = 3.9, P = .01), the International Consensus Meeting (aOR = 3.1, P = .01), and the Auckland classifications (aOR = 2.6, P = .01). Success was lower in both hematogenous (aOR = 0.4, P = .03) and chronic infections (aOR = 0.1, P = .003). CONCLUSION: Time since primary TKA is an important predictor of DAIR success. Success was highest in infections occurring <1 month of the primary TKA and progressively decreased as time since the primary TKA increased.

Frequency of pharmacological target attainment with flucloxacillin and cefazolin in invasive methicillin-susceptible Staphylococcus aureus infection: a prospective cohort study in hospitalized patients.

BACKGROUND: The proportion of patients with invasive methicillin-susceptible Staphylococcus aureus (MSSA) infection who achieve target concentrations of flucloxacillin or cefazolin with standard dosing regimens is uncertain. This study measured drug concentrations in a prospective cohort of patients with invasive S. aureus infections to determine the frequency of target concentration attainment, and risk factors for failure to achieve target concentrations. PATIENTS AND METHODS: Unbound flucloxacillin and cefazolin plasma concentrations were measured at the midpoint between intravenous doses. Adequate and optimal targets were defined as an unbound plasma concentration of ≥1 and ≥2 times the minimum inhibitory concentration (MIC) (flucloxacillin 0.5 mg/L, cefazolin 2 mg/L), respectively (50%fT≥1MIC, 50%fT≥2MIC). RESULTS: There were 50 patients in each of the flucloxacillin and cefazolin groups. Eighty-five (85%) patients met the target of 50%fT≥2MIC and 95 (95%) patients met the target of 50%fT≥1MIC. The median unbound flucloxacillin concentration was 2.6 mg/L [interquartile range (IQR) 1.0-8.1]. The median unbound cefazolin concentration was 15.4 mg/L (IQR 8.8-28.2). A higher proportion of patients in the flucloxacillin group failed to achieve the optimal target compared with the cefazolin group [13 (26%) vs 2 (4%); P=0.002]. Younger age and higher creatinine clearance were associated with lower plasma concentrations. CONCLUSIONS: Standard dosing of flucloxacillin and cefazolin in the treatment of invasive MSSA infections may not achieve target plasma concentrations for a subgroup of patients. Measuring drug concentrations identifies this subgroup and facilitates dose individualization.

Characteristics and outcomes of culture-negative prosthetic joint infections from the Prosthetic Joint Infection in Australia and New Zealand Observational (PIANO) cohort study.

Introduction: Culture-negative (CN) prosthetic joint infections (PJIs) account for approximately 10 % of all PJIs and present significant challenges for clinicians. We aimed to explore the significance of CN PJIs within a large prospective cohort study, comparing their characteristics and outcomes with culture-positive (CP) cases. Methods: The Prosthetic joint Infection in Australia and New Zealand Observational (PIANO) study is a prospective, multicentre observational cohort study that was conducted at 27 hospitals between 2014 and 2017. We compared baseline characteristics and outcomes of all patients with CN PJI from the PIANO cohort with those of CP cases. We report on PJI diagnostic criteria in the CN cohort and apply internationally recognized PJI diagnostic guidelines to determine optimal CN PJI detection methods. Results: Of the 650 patients with 24-month outcome data available, 55 (8.5 %) were CN and 595 were CP. Compared with the CP cohort, CN patients were more likely to be female (32 (58.2 %) vs. 245 (41.2 %); p   =  0.016), involve the shoulder joint (5 (9.1 %) vs. 16 (2.7 %); p   =  0.026), and have a lower mean C-reactive protein (142 mg L - 1 vs. 187 mg L - 1 ; p   =  0.016). Overall, outcomes were superior in CN patients, with culture negativity an independent predictor of treatment success at 24 months (adjusted odds ratio, aOR, of 3.78 and 95 %CI of 1.65-8.67). Suboptimal diagnostic sampling was common in both cohorts, with CN PJI case detection enhanced using the Infectious Diseases Society of America PJI diagnostic guidelines. Conclusions: Current PJI diagnostic guidelines vary substantially in their ability to detect CN PJI, with comprehensive diagnostic sampling necessary to achieve diagnostic certainty. Definitive surgical management strategies should be determined by careful assessment of infection type, rather than by culture status alone.

Short- versus standard-course intravenous antibiotics for peri-prosthetic joint infections managed with debridement and implant retention: a randomised pilot trial using a desirability of outcome ranking (DOOR) endpoint.

BACKGROUND: Peri-prosthetic joint infection (PJI) is a devastating complication of joint replacement surgery. Determining the optimal duration of intravenous (IV) antibiotics for PJI managed with debridement and implant retention (DAIR) is a research priority. METHODS: Patients undergoing DAIR for early and late-acute PJI of the hip or knee were randomised to receive 2 (short-course) or 6 (standard-course) weeks of IV antibiotics, with both groups completing 12 weeks of antibiotics in total. The primary endpoint of this pilot, open-label, randomised trial was a 7-point ordinal desirability of outcome ranking (DOOR) score, which accounted for mortality, clinical cure and treatment adverse events at 12 months. Duration of IV treatment was used as a tiebreaker, with shorter courses ranked higher. Outcome adjudication was performed by expert clinicians blinded to the allocated intervention (Australia and New Zealand Clinical Trials Registry ACTRN12617000127303). RESULTS: 60 patients were recruited; 31 and 29 were allocated to short- and standard-course treatment, respectively. All had an evaluable outcome at 12 months and were analysed by intention-to-treat. Clinical cure was demonstrated in 44 (73%) overall; 22 (71%) in the short-course group and 22 (76%) in the standard-care group (P=0.77). Using the DOOR approach, the probability that short- was better than standard-course treatment was 59.7% (95% confidence interval 45.1-74.3). CONCLUSIONS: In selected patients with early and late-acute PJI managed with DAIR, shorter courses of IV antibiotics may be appropriate. Due to small sample size, these data accord with, but do not confirm, results from other international trials of early transition to oral antibiotics.

Predictors of Treatment Success After Periprosthetic Joint Infection: 24-Month Follow up From a Multicenter Prospective Observational Cohort Study of 653 Patients.

BACKGROUND: Periprosthetic joint infection (PJI) is a devastating condition and there is a lack of evidence to guide its management. We hypothesized that treatment success is independently associated with modifiable variables in surgical and antibiotic management. METHODS: The is a prospective, observational study at 27 hospitals across Australia and New Zealand. Newly diagnosed large joint PJIs were eligible. Data were collected at baseline and at 3, 12, and 24 months. The main outcome measures at 24 months were clinical cure (defined as all of the following: alive, absence of clinical or microbiological evidence of infection, and not requiring ongoing antibiotic therapy) and treatment success (clinical cure plus index prosthesis still in place). RESULTS: Twenty-four-month outcome data were available for 653 patients. Overall, 449 patients (69%) experienced clinical cure and 350 (54%) had treatment success. The most common treatment strategy was debridement and implant retention (DAIR), with success rates highest in early postimplant infections (119 of 160, 74%) and lower in late acute (132 of 267, 49%) and chronic (63 of 142, 44%) infections. Selected comorbidities, knee joint, and Staphylococcus aureus infections were independently associated with treatment failure, but antibiotic choice and duration (including rifampicin use) and extent of debridement were not. CONCLUSIONS: Treatment success in PJI is associated with (1) selecting the appropriate treatment strategy and (2) nonmodifiable patient and infection factors. Interdisciplinary decision making that matches an individual patient to an appropriate management strategy is a critical step for PJI management. Randomized controlled trials are needed to determine the role of rifampicin in patients managed with DAIR and the optimal surgical strategy for late-acute PJI.

Proposed empiric antibiotic therapy for prosthetic joint infections: an analysis of the Prosthetic Joint Infection in Australia and New Zealand, Observational (PIANO) cohort.

Empiric antibiotic therapy in suspected prosthetic joint infection should cover likely pathogens while avoiding overly broad-spectrum antibiotics. We analysed individual patient data from a large prospective cohort study (Prosthetic Joint Infection in Australia and New Zealand, Observational (PIANO)) and found that causative organisms vary with the presentation type, with early post-operative infections more likely to be polymicrobial (41%) compared with late acute infections (10%). We thus propose empirical regimens tailored to the presentation type and presence or absence of sepsis.

Population pharmacokinetics of free flucloxacillin in patients treated with oral flucloxacillin plus probenecid.

Oral flucloxacillin may be coadministered with probenecid to reduce flucloxacillin clearance and increase attainment of pharmacokinetic-pharmacodynamic (PK/PD) targets. The aims of this study were to develop a population PK model of free flucloxacillin when administered orally with probenecid, and to identify optimal dosing regimens for this combination. METHODS: We performed a prospective observational study of adults (45 participants) treated with oral flucloxacillin 1000 mg and probenecid 500 mg 8-hourly for proven or probable staphylococcal infections. Steady-state mid-dose-interval flucloxacillin measurements (45 concentrations) were combined with existing data from a crossover study of healthy participants receiving flucloxacillin with and without probenecid (11 participants, 363 concentrations). We developed a population pharmacokinetic model of free flucloxacillin concentrations within Monolix, and used Monte Carlo simulation to explore optimal dosing regimens to attain PK/PD targets proposed in the literature (free drug time above minimum inhibitory concentration). RESULTS: Flucloxacillin disposition was best described by a 1-compartment model with a lag time and first-order absorption. Free flucloxacillin clearance depended on probenecid, allometrically-scaled fat free mass (FFM) and estimated glomerular filtration rate (eGFR). Predicted PK/PD target attainment was suboptimal with standard dosing regimens with flucloxacillin alone, but substantially improved in the presence of probenecid. CONCLUSION: The simulation results reported can be used to identify dose regimens that optimise flucloxacillin exposure according to eGFR and FFM. Patients with higher FFM and eGFR may require the addition of probenecid and 6-hourly dosing to achieve PK/PD targets. The regimen was well-tolerated, suggesting a potential for further evaluation in controlled clinical trials to establish efficacy.

Point prevalence surveys of antimicrobial use in adult inpatients at Canterbury District Health Board Hospitals.

AIMS: To determine the nature and appropriateness of antimicrobial prescribing in adult inpatients at Canterbury District Health Board (CDHB). METHODS: Multidisciplinary teams collected clinical details for all adult inpatients on antimicrobial therapy at three CDHB facilities (~1,100 beds) and made standardised assessments based on the Australian National Antimicrobial Prescribing Survey (http://naps.org.au) against local guidelines and national funding criteria. RESULTS: Antimicrobial therapy was prescribed to 42% of inpatients (322/760), usually to treat infections [377/480 prescriptions (79%)], with amoxicillin+clavulanic acid the agent most commonly prescribed [72/480 prescriptions (15%)]. Of assessable prescriptions, 74% (205/278) were guideline compliant, 98% (469/480) were funding criteria compliant, and 83% (375/451) were appropriate clinically. Prescriptions for the most common indications-surgical prophylaxis [66/480 (14%)] and community-acquired pneumonia [56/480 (12%)]-were often non-compliant with guidelines (32% and 41%, respectively) and inappropriate (18% and 21%, respectively). Overall, the indication was documented in 353/480 (74%) prescriptions, the review/stop date documented in 145/480 (30%) prescriptions, and surgical prophylaxis stopped within 24 hours in 53/66 (80%) prescriptions. CONCLUSIONS: Most antimicrobial prescriptions were appropriate and complied with guidelines. Compliance with key quality indicators (indication documented, review/stop date documented, and surgical prophylaxis ceased within 24 hours) were well below target (>95%) and needs improvement.

Clinical Characteristics, Etiology, and Initial Management Strategy of Newly Diagnosed Periprosthetic Joint Infection: A Multicenter, Prospective Observational Cohort Study of 783 Patients.

BACKGROUND: Periprosthetic joint infection (PJI) is a devastating complication of joint replacement surgery. Most observational studies of PJI are retrospective or single-center, and reported management approaches and outcomes vary widely. We hypothesized that there would be substantial heterogeneity in PJI management and that most PJIs would present as late acute infections occurring as a consequence of bloodstream infections. METHODS: The Prosthetic joint Infection in Australia and New Zealand, Observational (PIANO) study is a prospective study at 27 hospitals. From July 2014 through December 2017, we enrolled all adults with a newly diagnosed PJI of a large joint. We collected data on demographics, microbiology, and surgical and antibiotic management over the first 3 months postpresentation. RESULTS: We enrolled 783 patients (427 knee, 323 hip, 25 shoulder, 6 elbow, and 2 ankle). The mode of presentation was late acute (>30 days postimplantation and <7 days of symptoms; 351, 45%), followed by early (≤30 days postimplantation; 196, 25%) and chronic (>30 days postimplantation with ≥30 days of symptoms; 148, 19%). Debridement, antibiotics, irrigation, and implant retention constituted the commonest initial management approach (565, 72%), but debridement was moderate or less in 142 (25%) and the polyethylene liner was not exchanged in 104 (23%). CONCLUSIONS: In contrast to most studies, late acute infection was the most common mode of presentation, likely reflecting hematogenous seeding. Management was heterogeneous, reflecting the poor evidence base and the need for randomized controlled trials.

A persuasive approach to antimicrobial stewardship in Christchurch hospitals produced a sustained decrease in intravenous clarithromycin dosing and expenditure via a switch to azithromycin orally.

AIMS: To assess a persuasive multimodel approach to decreasing unnecessary intravenous (IV) clarithromycin use for community-acquired pneumonia (CAP) in Canterbury District Health Board (CDHB) hospitals. METHODS: In December 2013, CDHB guidelines for empiric treatment of CAP changed to prioritise oral azithromycin over IV clarithromycin. The multimodel approach we used to implement this change included obtaining stakeholder agreement, improved guidelines access, education and pharmacist support. The impact of the intervention was evaluated by comparing macrolide usage and expenditure for the four years pre- and post-intervention. RESULTS: Mean annual clarithromycin IV use decreased by 72% from 6.4 to 1.8 defined daily doses (DDDs) per 1,000 occupied bed days (OBDs) post-intervention, while oral azithromycin increased by 833% (4.2 to 39.2 DDDs per 1,000 OBDs). Concurrently, oral clarithromycin use decreased by 91% (32.9 to 2.9 DDDs per 1,000 OBDs), and roxithromycin by 71% (17.0 to 5.0 DDDs per 1,000 OBDs). Mean annual total macrolide use decreased by 21% (68.2 to 53.9 DDDs per 1,000 OBDs), while expenditure decreased by 69% mainly through avoided IV administration. CONCLUSIONS: A persuasive multimodel approach to support adoption of CAP guidelines produced a sustained decrease in IV clarithromycin use, which may have clinical benefits such as reduced occurrence of catheter-related complications.

Determinants of vancomycin nephrotoxicity when administered to outpatients as a continuous 24-hour infusion.

Vancomycin continuous infusion (VCI) is used to treat serious Gram-positive infections in outpatients. This study was conducted to retrospectively investigate the rate of nephrotoxicity and associated risk factors in out-patients on VCI between May 2013 and November 2018. Vancomycin concentration was monitored twice-weekly to ensure adequate concentrations while avoiding high concentrations linked to nephrotoxicity (a rise in serum creatinine of ≥50% or 44 µmol/L from baseline). The likelihood of developing nephrotoxicity was evaluated using multivariable logistic regression. The 223 patients treated had a mean (standard deviation) age of 61 (16.7) years, baseline serum creatinine of 83.9 (21.2) µmol/L and estimated glomerular filtration rate (eGFR) of 80.6 (20.1) mL/min/1.73m2. Most patients (66%) were treated for bone and joint infections. Eight patients (3.6%) developed nephrotoxicity. In the most parsimonious model, nephrotoxicity was independently associated with an increased median (interquartile range) weighted-average serum vancomycin concentration (28.0 [24.3-32.6] vs. 22.4 [20.2-24.5] mg/L; odds ratio [OR] 1.25; 95% confidence interval [95% CI] 1.09-1.46; P<0.002) and Charlson co-morbidity index (OR 1.62; 95% CI 1.07-2.47; P=0.02). Post-hoc analysis identified 26 patients with a lower nephrotoxicity threshold (rise in serum creatinine of ≥30% or 27 µmol/L). Independent predictors of nephrotoxicity in this group were an increased weighted-average vancomycin concentration, diabetes, con-gestive heart failure and exposure to non-loop diuretics. The nephrotoxicity rate during VCI in this study was lower than previously reported (3.6% vs 15.0-17.0%).  Reducing the weighted-average serum vancomycin concentration may reduce nephrotoxicity while maintaining efficacy.

Assessing the impact of a 'bundle of care' approach to Staphylococcus aureus bacteraemia in a tertiary hospital.

BACKGROUND: Staphylococcus aureus bacteraemia is associated with significant morbidity and mortality. There is evidence that standardised care bundle implementation may improve the rates of appropriate investigations and improve overall management. A S. aureus bacteraemia care bundle was introduced at Christchurch Hospital, New Zealand in early 2014. We assessed the impact of the intervention on the management and outcome of S. aureus bacteraemia. METHODS: A cohort study of cases of S. aureus bacteraemia was conducted following standardised care bundle introduction. Prospective enrolment of post-intervention patients occurred from 1st January 2014 to 30th June 2015, with retrospective review of pre-intervention cases from 1st January 2009 to 31st December 2013. RESULTS: In the pre-intervention period 447 patients had at least one episode of S. aureus bacteraemia compared to 151 patients in the post-intervention period. The two groups were similar by gender, ethnicity, and age. Significant increases in Infectious Diseases consultation rate (86.6% vs 94.8%; p=0.009), echocardiography (76.3% vs 96.3%; p<0.001), urine culture (74.0% vs 91.9%; p<0.001), follow up blood cultures (44.2% vs 83.0%; p<0.001), and at least 2 weeks of parenteral therapy (83.5% vs 92.9%; p=0.014) were observed after introduction of the bundle. There were no significant differences in rates 30-day mortality (18.6% vs. 20.5%; p=0.596), but there was a reduction in episodes of relapsed infection in the post-intervention cohort (7.4% vs 1.3%; p=0.004). CONCLUSION: An integrated care bundle for the management of S. aureus bacteraemia resulted in increased use of quality of care indicators and infectious diseases review and improved patient outcome.

Urinalysis orders and yield among General Medicine patients: a single-centre's experience in New Zealand.

BACKGROUND: Urinalysis performed by dipstick testing is an aid to diagnosing urinary tract infections (UTI), and a tool in selecting patients who require urine culture and antibiotic treatment. Previous studies have demonstrated that UTI, especially in the elderly, are over-diagnosed and over-treated. We sought to study the pattern and yield of urinalysis and urine culture at our service in a tertiary institution. METHODS: A convenience sampling method was utilised to prospectively collect clinical data, through a pre-designed pro forma, from patients admitted to the General Medicine service at Christchurch Hospital between March and June 2016. RESULTS: The study included 395 patients, with a median age of 76 (range 15-100 years). The presence of urinary tract symptoms was documented in 94 patients (24%) and a non-specific syndrome of elevated temperature, confusion or subjective feverishness in 69 (17%). In symptomatic patients, 121 (74%) had a dipstick performed and 104 (86%) urine samples cultured. In the remaining patients, 181 (78%) had a dipstick performed and 81 (35%) had a urine sample sent for culture. CONCLUSIONS: We found a large number of urine dipsticks is being ordered unnecessarily in asymptomatic patients. A more useful test is urine microscopy and culture that is done on symptomatic patients only following careful clinical evaluation. Performing 'routine' urinalysis in patients presenting a wide variety of symptoms may lead to unnecessary urine cultures and treatment of asymptomatic bacteriuria. Efforts to reduce unnecessary tests and antibiotic treatment are a vital component of diagnostic stewardship programmes.

Outpatient parenteral antimicrobial therapy (OPAT) in Christchurch: 18 years on.

AIM: Outpatient parenteral antimicrobial therapy (OPAT) has become an established option for management infections requiring intravenous therapy. As the uptake of OPAT has increased, the clinical governance has changed and is now managed via virtual clinics and increased use of district nurses in addition to specialist outpatient review. The aim of this study was to report the characteristics, diagnoses, treatment and outcomes of patients managed by the service over 12 months in 2015/6 and compared these features with those of patients treated with OPAT in 1999. METHODS: Cases for 2015/6 were identified from the OPAT service database which records prospectively all information on diagnosis, antibiotic choice and duration of treatment, complications and requirement for review by the ID physicians and OPAT nurses prospectively. The outcomes, complications and readmissions were found by reviewing computerised records of Christchurch Hospital. All results were entered into a Microsoft® Excel database for analysis. Statistical analyses were performed using OpenEpi software. Data for 1999 was taken from an earlier publication. RESULTS: OPAT treatment in 12 months from 1 July 2015 was administered 407 times to 385 patients, which represented a 2.7 times increase in treatment courses than in 1999. The median age was 55 years in 1999 and 61 in 2015/6. There was a substantial increase in the proportion of bone and joint, abdominal and urinary tract infections but a fall in cellulitis and soft tissue infection. The number and proportion of patients treated with broad spectrum agents including piperacillin + tazobactam, ceftriaxone and carbapenems increased from 1% in 1999 to 20% in 2015/6. Unplanned readmission to hospital increased from 15 (10%) in 1999 to 62 patients (15%) in 2015/6. The most common reason for readmission in 2015/6 was for ongoing symptoms or progression of the infection requiring OPAT. Eight patients (2%) required readmission from adverse reactions to antimicrobial therapy. Two patients on palliative care died while on OPAT and 35 (9%) within 12 months of the index admission. CONCLUSION: OPAT use has increased and is used to treat patients with comorbidities, who are older, and with a different case-mix than 1999. Safety has not been compromised but the risk of treatment failure has increased. A better understanding of the reasons for treatment failure would improve patient selection and management with OPAT.

Soft Tissue Infection with Diaporthe phaseolorum in Heart Transplant Recipient with End-Stage Renal Failure.

Diaporthe phaseolorum is a fungal plant parasite that has rarely been described as causing invasive human disease. We report a case of human soft tissue infection with Diaporthe phaseolorum in a heart transplant patient with end-stage renal failure in New Zealand.

Antimicrobial stewardship practice in New Zealand's rural hospitals.

AIMS: We aimed to describe how antimicrobial stewardship (AMS) is practised in New Zealand's diverse rural hospital network. METHODS: Rural hospital medical practitioners were surveyed to estimate the utilisation of prescribing resources and specialist support for AMS, and attitudes towards AMS. Questions reflected recommended strategies for AMS programmes. RESULTS: The response rate was 80.8% (122/151) from 29 rural hospitals (3-114 beds). While 78.7% reported access to local antimicrobial prescribing guidelines, discordant answers from practitioners at the same institution were common. The practice of approval for access to broad-spectrum antimicrobial agents was uncommon. Most respondents had cared for a patient with a multi-drug resistant organism in the preceding 12 months. Only 34.8% of respondents reported receiving formal education on AMS principles, with at least 90% believing it was relevant irrespective of the clinical context considered. Respondents were more likely to believe that antimicrobial overuse and resistance were more relevant at sites distant from the context of rural hospital practice. CONCLUSION: While AMS is perceived as relevant for rural hospital medicine, many of the building blocks of AMS systems are absent in this environment. This presents an opportunity for development as AMS strategies evolve in New Zealand.