State transitions across the Strep A disease spectrum: scoping review and evidence gaps

The spectrum of diseases caused by Streptococcus pyogenes (Strep A) ranges from superficial to serious life-threatening invasive infections. We conducted a scoping review of published articles between 1980 and 2021 to synthesize evidence of state transitions across the Strep A disease spectrum. We identified 175 articles reporting 262 distinct observations of Strep A disease state transitions. Among the included articles, the transition from an invasive or toxin-mediated disease state to another disease state (i.e., to recurrent ARF, RHD or death) was described 115 times (43.9% of all included transition pairs) while the transition to and from locally invasive category was the lowest (n = 7; 0.02%). Transitions from well to any other state was most frequently reported (49%) whereas a relatively higher number of studies (n = 71) reported transition from invasive disease to death. Transitions from any disease state to locally invasive, Strep A pharyngitis to invasive disease, and chronic kidney disease to death were lacking. Transitions related to severe invasive diseases were more frequently reported than superficial ones. Most evidence originated from high-income countries and there is a critical need for new studies in low- and middle-income countries to infer the state transitions across the Strep A disease spectrum in these high-burden settings.

Trends in penicillin dispensing during an acute rheumatic fever prevention programme

AIM

Acute rheumatic fever (ARF), a serious inflammatory condition, often leads to rheumatic heart disease (RHD). Between 2011 and 2016, Aotearoa New Zealand implemented a rheumatic fever prevention programme (RFPP) to reduce high rates of ARF through improved community access to timely diagnosis and early treatment of group A streptococcal (GAS) pharyngitis, which has been shown to prevent subsequent ARF. This study aimed to quantify the change in penicillin antibiotic dispensing rates among children aged 18 years or younger during the RFPP.

METHOD

This retrospective analysis utilised administrative data from the National Pharmaceutical Collection. Using a controlled, interrupted time series analysis, the effect of the RFPP on antibiotic dispensing rates was explored. Poisson regression models were used to assess the change in dispensing rates during the RFPP among control regions (those not in the RFPP) and regions participating in the RFPP. The primary measure was rate ratio (RR) for the difference between the observed versus counterfactual rates of penicillin dispensing.

RESULT

A total of 12,154,872 dispensing records between 2005 and 2018 were included. Amoxicillin was the most frequently dispensed penicillin (57.7%), followed by amoxicillin-clavulanate (23.4%). Amoxicillin dispensing increased by 4.3% in regions operating the RFPP compared to the increase in control regions (p<0.001). The overall rate of penicillin dispensing decreased, driven by a rapid decline in amoxicillin-clavulanate dispensing.

CONCLUSION

During the RFPP an increase in amoxicillin dispensing was seen in regions participating in the programme and regions outside of the programme, indicating the programmatic approach led to improved adherence to recommended first-line antibiotics.

The potential global cost-effectiveness of prospective Strep A vaccines and associated implementation efforts

Group A Streptococcus causes a wide range of diseases from relatively mild infections including pharyngitis to more severe illnesses such as invasive diseases and rheumatic heart disease (RHD). Our aim is to estimate the cost-effectiveness of a hypothetical Strep A vaccine on multiple disease manifestations at the global-level. Cost-effectiveness analyses were carried out by building on the potential epidemiological impact of vaccines that align with the WHO's Preferred Product Characteristics for Strep A vaccines. Maximum vaccination costs for a cost-effective vaccination strategy were estimated at the thresholds of 1XGDP per capita and health opportunity costs. The maximum cost per fully vaccinated person for Strep A vaccination to be cost-effective was $385-$489 in high-income countries, $213-$312 in upper-income-income countries, $74-$132 in lower-middle-income countries, and $37-$69 in low-income countries for routine vaccination at birth and 5 years of age respectively. While the threshold costs are sensitive to vaccine characteristics such as efficacy, and waning immunity, a cost-effective Strep A vaccine will lower morbidity and mortality burden in all income settings.

Heat shock protein response during fixed intensity and self-paced exercise in the heat in young, healthy women on oral contraceptives compared with young healthy men

Background

Heat shock proteins respond to a variety of physiological and environmental stresses, including heat stress, ischemia and endotoxic shock. Hormonal changes during the female menstrual cycle can have a thermogenic effect on body temperature. The monophasic oral contraceptive (OC) pill provides low doses of progesterone and oestrogen over the course of the normal menstrual phase. There is little evidence regarding the combined effects of OC on exercise performance and heat stress with respect to heat shock protein response.

Objectives

This study aimed to determine the response of heat shock proteins (Hsp72) during fixed-intensity and self-paced exercise in the heat in young, healthy women on oral contraceptives compared with young healthy men.

Methods

Sixteen physically active men and women performed 30 min fixed-intensity cycling at 50% of maximum workload, followed by 30 min of a self-paced time trial (TT) interspersed by 30 s maximal sprint at 9, 19 and 29 min respectively. Trials were undertaken in cool (20°C; 48±3% relative humidity (RH)) and warm (32°C; 66±2% RH) ambient conditions. Core (T _c) and skin temperature, heart rate (HR) and subjective responses were measured before, during and post exercise.

Results

The distance, mean and peak power output, mean and peak speed during the self-paced time trial showed no difference between the ambient temperatures for men and women. Hsp72 in females was higher than males at all sample points at both 20°C and 32°C, except for pre-exercise at 20°C (p< 0.04). Women also attained a higher T _c than men at the end of the TT in the heat (38.5°C v 37.9°C for women and men, respectively; p<0.03), higher mean HR and perceived exertion.

Conclusion

This study indicates that females who use oral contraceptives (OC) had higher levels of Hsp72 than males when tested under the same environmental conditions.

Standardization of Epidemiological Surveillance of Group A Streptococcal Pharyngitis

Pharyngitis, more commonly known as sore throat, is caused by viral and/or bacterial infections. Group A Streptococcus (Strep A) is the most common bacterial cause of pharyngitis. Strep A pharyngitis is an acute, self-limiting disease but if undertreated can lead to suppurative complications, nonsuppurative poststreptococcal immune-mediated diseases, and toxigenic presentations. We present a standardized surveillance protocol, including case definitions for pharyngitis and Strep A pharyngitis, as well as case classifications that can be used to differentiate between suspected, probable, and confirmed cases. We discuss the current tests used to detect Strep A among persons with pharyngitis, including throat culture and point-of-care tests. The type of surveillance methodology depends on the resources available and the objectives of surveillance. Active surveillance and laboratory confirmation is the preferred method for case detection. Participant eligibility, the surveillance population and additional considerations for surveillance of pharyngitis are addressed, including baseline sampling, community engagement, frequency of screening and season. Finally, we discuss the core elements of case report forms for pharyngitis and provide guidance for the recording of severity and pain associated with the course of an episode.

Standardization of Epidemiological Surveillance of Group A Streptococcal Impetigo

Impetigo is a highly contagious bacterial infection of the superficial layer of skin. Impetigo is caused by group A Streptococcus (Strep A) and Staphylococcus aureus, alone or in combination, with the former predominating in many tropical climates. Strep A impetigo occurs mainly in early childhood, and the burden varies worldwide. It is an acute, self-limited disease, but many children experience frequent recurrences that make it a chronic illness in some endemic settings. We present a standardized surveillance protocol including case definitions for impetigo including both active (purulent, crusted) and resolving (flat, dry) phases and discuss the current tests used to detect Strep A among persons with impetigo. Case classifications that can be applied are detailed, including differentiating between incident (new) and prevalent (existing) cases of Strep A impetigo. The type of surveillance methodology depends on the burden of impetigo in the community. Active surveillance and laboratory confirmation is the preferred method for case detection, particularly in endemic settings. Participant eligibility, surveillance population and additional considerations for surveillance of impetigo, including examination of lesions, use of photographs to document lesions, and staff training requirements (including cultural awareness), are addressed. Finally, the core elements of case report forms for impetigo are presented and guidance for recording the course and severity of impetigo provided.

Assessment and outcomes of firefighter applicants with possible asthma

BACKGROUND

Firefighter applicants (FFAs) with a history of asthma may be refused entry to the fire service because of potentially putting themselves and others at risk.

AIMS

We undertook a service evaluation to identify respiratory and employment outcomes of FFAs with a history of asthma who had undergone additional respiratory assessment at our specialist occupational lung disease clinic during 2005-19.

METHODS

We reviewed FFA medical records and categorized them as having either no current asthma or definite/probable asthma at the time of clinic assessment. 'No current asthma' was defined as negative non-specific bronchial hyper-responsiveness (BHR) to histamine/methacholine, and no symptoms or treatment within the 2 years before clinic. 'Definite/probable current asthma' was defined as either positive BHR, or negative BHR with symptoms and/or treatment within the previous 2 years. Around 1 year later, we contacted FFAs to enquire about their application outcome and current respiratory symptoms.

RESULTS

Data were available on 116 applicants; of whom, 45% (n = 52) had definite/probable current asthma and were significantly more likely to be older, atopic to common aeroallergens, report atopic disease and have a lower forced expiratory volume in one second/forced vital capacity ratio compared with applicants with no current asthma. Only two individuals' applications were rejected due to asthma. At follow-up, just 2 (2%) of the 90 operational firefighters reported any recent trouble with asthma.

CONCLUSIONS

A history of asthma alone is not sufficient to determine current asthma in FFAs. Even with a diagnosis of current asthma, FFAs are mostly successful in their application to join the fire service.

Prevalence and clinical impact of atrioventricular conduction disease in patients with idiopathic pulmonary arterial hypertension

Background

Although bradycardia-related sudden death is common in patients with idiopathic pulmonary arterial hypertension (IPAH), the prevalence and prognostic significance of atrioventricular (AV) conduction disease in this patient group is not well-established.

Objectives

– Determine the prevalence of AV conduction disorders in patients with IPAH

– Investigate the relationship between AV block and functional outcomes and mortality.

Method

12-lead electrocardiograms (ECGs) of patients with IPAH were analysed. Patients were categorised according to the presence or absence of AV block. Demographic, pulmonary haemodynamic, cardiac structural characteristics and expression of genes associated with cardiac conduction were compared and functional and mortality outcomes analysed between groups.

Student's t-tests and χ2 tests were used to compare data. Survival was estimated using Kaplan-Meier analyses. Initial exploratory covariates were included in a univariate analysis and those terms with P-value of &lt;0.1 were then used to generate a Cox proportional-hazards multivariate model.

Results

135 IPAH patients (mean age 55±16 years, 28.1% male) were eligible for analysis. Median follow up was 9 years (interquartile range 4–14 years).

AV block was seen in 34.8% of patients with IPAH compared to 10.8% of matched comparators (p&lt;0.001), drawn from patients attending hospital for non-PAH related reasons.

IPAH patients with conduction disease were more likely to be older (59±16 vs 53±17 years, p=0.038). AV block was associated with more severe right ventricular (RV) basal dilatation (5.1±1.0 vs 4.3±0.7cm, p=0.013) and worse RV function (fractional area change 26±9% vs 31±9%, p=0.14). Pulmonary haemodynamics, right atrial size and resting and exertional oxygen saturations were not significantly different. Expression of HCN1, HCN2, SCN1B, SCN5A, CAV1, and KCN2 genes in peripheral blood from a subcohort was similar between those with and without AV block.

Lower 6 minute walk distances (344±153 vs 408±140m, p=0.035) and worse CAMPHOR scores across all 3 domains were seen in those with AV block (figure 1), and mortality was significantly higher (36.2 vs 13.6%, p=0.002) (figure 2). On multivariate analysis the presence of bundle branch block (BBB) was independently associated with a 2.1-fold increased risk of death (95% CI 1.89–4.85, p=0.045).

Conclusions

AV conduction disorders are more prevalent in IPAH than the general population, and are associated with worse prognosis and functional status. Prospective study is required to validate this finding.

In our cohort AV block could not be explained by hypoxia, differences in pulmonary haemodynamics nor, in a small subgroup, by differential expression of specific transmembrane ion channels implicated in cardiac conduction. More detailed investigation into causal mechanisms of AV block in IPAH could establish whether improved prognosis could be achieved by treatment of AV block.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Cellulitis in children: a retrospective single centre study from Australia

AIM

To characterise the epidemiology, clinical features and treatment of paediatric cellulitis.

METHODS

A retrospective study of children presenting to a paediatric tertiary hospital in Western Australia, Australia in 2018. All inpatient records from 1 January to 31 December 2018 and emergency department presentations from 1 July to 31 December 2018 were screened for inclusion.

RESULTS

302 episodes of cellulitis were included comprising 206 (68.2%) admitted children and 96 (31.8%) non-admitted children. The median age was 5 years (IQR 2-9), 40 (13.2%) were Aboriginal and 180 (59.6%) boys. The extremities were the most commonly affected body site among admitted and non-admitted patients. There was a greater proportion of facial cellulitis in admitted patients (27.2%) compared with non-admitted patients (5.2%, p<0.01). Wound swab was the most frequent microbiological investigation (133/302, 44.0%), yielding positive cultures in the majority of those tested (109/133, 82.0%). The most frequent organisms identified were Staphylococcus aureus (94/109, 86.2%) (methicillin-susceptible S. aureus (60/94, 63.8%), methicillin-resistant S. aureus) and Streptococcus pyogenes (22/109, 20.2%) with 14 identifying both S. aureus and S. pyogenes. Intravenous flucloxacillin was the preferred antibiotic (154/199, 77.4%), with median intravenous duration 2 days (IQR 2-3), oral 6 days (IQR 5-7) and total 8 days (IQR 7-10).

CONCLUSIONS

Cellulitis is a common reason for presentation to a tertiary paediatric hospital. We confirm a high prevalence of extremity cellulitis and demonstrate that children with facial cellulitis often require admission. Cellulitis disproportionately affected Aboriginal children and children below 5 years. Prevention of cellulitis involves early recognition and treatment of skin infections such as impetigo and scabies.

Ending rheumatic heart disease in Australia: the evidence for a new approach

■The RHD Endgame Strategy: the blueprint to eliminate rheumatic heart disease in Australia by 2031 (the Endgame Strategy) is the blueprint to eliminate rheumatic heart disease (RHD) in Australia by 2031. Aboriginal and Torres Strait Islander people live with one of the highest per capita burdens of RHD in the world. ■The Endgame Strategy synthesises information compiled across the 5-year lifespan of the End Rheumatic Heart Disease Centre of Research Excellence (END RHD CRE). Data and results from priority research projects across several disciplines of research complemented literature reviews, systematic reviews and narrative reviews. Further, the experiences of those working in acute rheumatic fever (ARF) and RHD control and those living with RHD to provide the technical evidence for eliminating RHD in Australia were included. ■The lived experience of RHD is a critical factor in health outcomes. All future strategies to address ARF and RHD must prioritise Aboriginal and Torres Strait Islander people's knowledge, perspectives and experiences and develop co-designed approaches to RHD elimination. The environmental, economic, social and political context of RHD in Australia is inexorably linked to ending the disease. ■Statistical modelling undertaken in 2019 looked at the economic and health impacts of implementing an indicative strategy to eliminate RHD by 2031. Beginning in 2019, the strategy would include: reducing household crowding, improving hygiene infrastructure, strengthening primary health care and improving secondary prophylaxis. It was estimated that the strategy would prevent 663 deaths and save the health care system $188 million. ■The Endgame Strategy provides the evidence for a new approach to RHD elimination. It proposes an implementation framework of five priority action areas. These focus on strategies to prevent new cases of ARF and RHD early in the causal pathway from Streptococcus pyogenes exposure to ARF, and strategies that address the critical systems and structural changes needed to support a comprehensive RHD elimination strategy.

Follow-up survey of patients with occupational asthma

BACKGROUND

Occupational asthma (OA) is often associated with a poor prognosis and the impact of a diagnosis on an individual's career and income can be significant.

AIMS

We sought to understand the consequences of a diagnosis of OA to patients attending our clinic.

METHODS

Using a postal questionnaire, we surveyed all patients attending our specialist occupational lung disease clinic 1 year after having received a diagnosis of OA due to a sensitizer (n = 125). We enquired about their current health and employment status and impact of their diagnosis on various aspects of their life. Additional information was collected by review of clinical records.

RESULTS

We received responses from 71 (57%) patients; 77% were referred by an occupational health (OH) provider. The median duration of symptoms prior to referral was 18 months (interquartile range (IQR) 8-48). At 1 year, 79% respondents were no longer exposed to the causal agent. Whilst the unexposed patients reported an improvement in symptoms compared with those still exposed (82% versus 53%; P = 0.023), they had poorer outcomes in terms of career, income and how they felt treated by their employer; particularly those not currently employed. Almost all (>90%) of those still employed had been referred by an OH provider compared with 56% of those currently unemployed (P = 0.002)x.

CONCLUSIONS

The negative impact of OA on people's careers, livelihood and quality of life should not be underestimated. However, with early detection and specialist care, the prognosis is often good and particularly so for those with access to occupational health.

Contemporary Incidence and Prevalence of Rheumatic Fever and Rheumatic Heart Disease in Australia Using Linked Data: The Case for Policy Change

Background In 2018, the World Health Organization prioritized control of acute rheumatic fever (ARF) and rheumatic heart disease (RHD), including disease surveillance. We developed strategies for estimating contemporary ARF/RHD incidence and prevalence in Australia (2015-2017) by age group, sex, and region for Indigenous and non-Indigenous Australians based on innovative, direct methods. Methods and Results This population-based study used linked administrative data from 5 Australian jurisdictions. A cohort of ARF (age <45 years) and RHD cases (<55 years) were sourced from jurisdictional ARF/RHD registers, surgical registries, and inpatient data. We developed robust methods for epidemiologic case ascertainment for ARF/RHD. We calculated age-specific and age-standardized incidence and prevalence. Age-standardized rate and prevalence ratios compared disease burden between demographic subgroups. Of 1425 ARF episodes, 72.1% were first-ever, 88.8% in Indigenous people and 78.6% were aged <25 years. The age-standardized ARF first-ever rates were 71.9 and 0.60/100 000 for Indigenous and non-Indigenous populations, respectively (age-standardized rate ratio=124.1; 95% CI, 105.2-146.3). The 2017 Global Burden of Disease RHD prevalent counts for Australia (<55 years) underestimate the burden (1518 versus 6156 Australia-wide extrapolated from our study). The Indigenous age-standardized RHD prevalence (666.3/100 000) was 61.4 times higher (95% CI, 59.3-63.5) than non-Indigenous (10.9/100 000). Female RHD prevalence was double that in males. Regions in northern Australia had the highest rates. Conclusions This study provides the most accurate estimates to date of Australian ARF and RHD rates. The high Indigenous burden necessitates urgent government action. Findings suggest RHD may be underestimated in many high-resource settings. The linked data methods outlined here have potential for global applicability.

Development and Evaluation of a Prediction Model for Ascertaining Rheumatic Heart Disease Status in Administrative Data

Background

Previous research has raised substantial concerns regarding the validity of the International Statistical Classification of Diseases and Related Health Problems (ICD) codes (ICD-10 I05-I09) for rheumatic heart disease (RHD) due to likely misclassification of non-rheumatic valvular disease (non-rheumatic VHD) as RHD. There is currently no validated, quantitative approach for reliable case ascertainment of RHD in administrative hospital data.

Methods

A comprehensive dataset of validated Australian RHD cases was compiled and linked to inpatient hospital records with an RHD ICD code (2000-2018, n=7555). A prediction model was developed based on a generalized linear mixed model structure considering an extensive range of demographic and clinical variables. It was validated internally using randomly selected cross-validation samples and externally. Conditional optimal probability cutpoints were calculated, maximising discrimination separately for high-risk versus low-risk populations.

Results

The proposed model reduced the false-positive rate (FPR) from acute rheumatic fever (ARF) cases misclassified as RHD from 0.59 to 0.27; similarly for non-rheumatic VHD from 0.77 to 0.22. Overall, the model achieved strong discriminant capacity (AUC: 0.93) and maintained a similar robust performance during external validation (AUC: 0.88). It can also be used when only basic demographic and diagnosis data are available.

Conclusion

This paper is the first to show that not only misclassification of non-rheumatic VHD but also of ARF as RHD yields substantial FPRs. Both sources of bias can be successfully addressed with the proposed model which provides an effective solution for reliable RHD case ascertainment from hospital data for epidemiological disease monitoring and policy evaluation.

Seasonal and regional patterns of lower leg cellulitis in Western Australia

BACKGROUND

Lower leg cellulitis (LLC) is a common infection that is usually caused by Streptococcus pyogenes or other beta-haemolytic streptococci. We hypothesised that in Western Australia (WA), LLC is a summer disease and would be more common in the northern, tropical regions.

METHODS

We conducted a statewide data linkage of adult patients presenting to WA hospitals with a first ever diagnosis of LLC, from January 2002 through December 2013 according to the region and season.

RESULTS

A total of 36 276 cases presented with a primary episode of LLC. The northern regions of the Kimberley (2.26 (2.13-2.39), P < 0.001) and midwest (1.13 (1.06-1.20), P < 0.001) had higher incidence rates than the Perth metropolitan region, while the southern regions of Southwest, Great Southern and Goldfields had lower incidence rates (0.89 (0.85-0.93), P < 0.001; 0.81 (0.75-0.88), P < 0.001; and 0.77 (0.71-0.83), P < 0.001, respectively). The total number of primary cases was higher in summer (10 570 (29.1%, 95% confidence interval 28.7-29.6), P < 0.0001) and autumn (9306 (25.7%, 95% confidence interval 25.2-26.1), P = 0.004). Seasonality of LLC was observed in all WA regions except those in the Kimberley, Pilbara and Great Southern regions.

CONCLUSION

In most non-tropical regions of WA, LLC is a summer disease, while in the warmer tropical regions of WA where year-round temperatures are higher, no seasonality was observed, but overall incidence of LLC presentations were higher. These findings may have important implications for public health messaging and research around prevention of LLC.

Low positive predictive value of International Classification of Diseases, 10th Revision codes in relation to rheumatic heart disease: a challenge for global surveillance

International Classification of Diseases, 10th Revision codes for rheumatic heart disease (RHD) include valvular heart disease of unspecified origin, limiting their usefulness for estimating RHD burden. A cross-disciplinary national consultation developed an algorithm to improve RHD identification in hospital data. The algorithm has been operationalised and piloted. The algorithm developed categorised 32% of RHD-coded patients as probable/possible RHD. We outline a series of research initiatives to improve identification of RHD in administrative data thereby contributing to monitoring the RHD burden globally.

The End Rheumatic Heart Disease in Australia Study of Epidemiology (ERASE) Project: data sources, case ascertainment and cohort profile

PURPOSE

Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) persist as public health issues in developing countries and among disadvantaged communities in high-income countries, with rates in Aboriginal and Torres Strait Islander peoples in Australia among the highest recorded globally. A robust evidence base is critical to support policy recommendations for eliminating RHD, but available data are fragmented and incomplete. The End RHD in Australia: Study of Epidemiology (ERASE) Project aims to provide a comprehensive database of ARF and RHD cases in Australia as a basis for improved monitoring and to assess prevention and treatment strategies. The objective of this paper is to describe the process for case ascertainment and profile of the study cohort.

PATIENTS AND METHODS

The ERASE database has been built using linked administrative data from RHD registers, inpatient hospitalizations, and death registry data from 2001 to 2017 (mid-year). Additional linked datasets are available. The longitudinal nature of the data is harnessed to estimate onset and assess the progression of the disease. To accommodate systematic limitations in diagnostic coding for RHD, hospital-only identified RHD has been determined using a purposefully developed prediction model.

RESULTS

Of 132,053 patients for whom data were received, 42,064 are considered true cases of ARF or RHD in the study period. The patient population under 60 years in the compiled dataset is more than double the number of patients identified in ARF/RHD registers (12,907 versus 5049). Non-registered patients were more likely to be older, non-Indigenous, and at a later disease stage.

CONCLUSION

The ERASE Project has created an unprecedented linked administrative database on ARF and RHD in Australia. These data provide a critical baseline for efforts to end ARF/RHD in Australia. The methodological work conducted to compile this database resulted in significant improvements in the robustness of epidemiological estimates and entails valuable lessons for ARF/RHD research globally.

How does carrier status for recessive disorders influence reproductive decisions? A systematic review of the literature

Introduction: Carrier screening for recessive disorders is undertaken by prospective parents to inform their reproductive decisions. With the growing availability of affordable and comprehensive expanded carrier screening (ECS), it is expected that carrier screening will become a standard practice in the future. However, the impact of positive carrier screening results on the reproductive decisions of at-risk couples (ARCs) remains underexplored.Areas covered: We performed a systematic literature review to identify peer-reviewed publications describing the reproductive decisions of ARCs. Our search identified 19 relevant publications spanning the period 1994-2018. By synthesizing available evidence, we found that most ARCs chose to prevent the birth of an affected child and the decision to utilize preventive reproductive options was strongly influenced by the clinical nature of a disorder. However, there was also some heterogeneity in reproductive decisions within the same recessive disorders, suggesting that choices of ARCs can be influenced by factors other than the clinical nature of a disorder.Expert opinion: ECS is becoming increasingly common, which will result in the routine identification of many ARCs. Reproductive decision-making by ARCs is a complex and emotionally challenging process, highlighting the critical role of genetic counseling in the care for these potentially vulnerable patients.

Early removal of catheters in an Enhanced Recovery Pathway (ERP) with intrathecal opioid injection does not affect postoperative urinary outcomes

BACKGROUND

Postoperative urinary retention (POUR) and catheter-associated urinary tract infections (CAUTI) are associated with significantly longer hospital length-of-stay and increased costs.¹ This study investigates the effect of early removal of urinary catheters on POUR and CAUTI in patients undergoing an ERP with a preoperative intrathecal injection.

METHODS

Retrospective cohort study of a prospectively maintained database of patients who underwent elective colorectal surgery in an Enhanced Recovery pathway was compared to historical National Surgical Quality Improvement Program cohort of patients. Primary outcomes measured are 30-day POUR and postoperative CAUTI rates.

RESULTS

The overall POUR rate of ERP patients compared to non-ERP patients was significantly less (8% vs. 13%, p < 0.05). CAUTI rates were not significantly different between pre-ERP and ERP patients (1.2 vs 2.3%, p = 0.19).

CONCLUSIONS

For patients undergoing ERP with a preoperative intrathecal opioid injection, early removal of urinary catheter significantly decreased POUR and did not significantly affect CAUTI rates.

SUMMARY

The effect of early removal of urinary catheters on postoperative urinary retention and catheter-associated UTI rates in patients undergoing an ERP with a single preoperative intrathecal opioid injection was studied. Early urinary catheter removal after intrathecal injection was associated with decreased rates of POUR and equivalent CAUTI rates.

Prospective cohort study of childhood behaviour problems and adolescent sexual risk-taking: gender matters

Background Externalising (delinquent, aggressive) and internalising (anxious/depressed, withdrawn) behaviour problems are prevalent in childhood. Few studies have prospectively measured relationships between childhood behaviour problems and adolescent health risk behaviour, a major predictor of morbidity and mortality. This study sought to determine relationships, by gender, between childhood behaviour problems and adolescent risky sexual behaviours and substance use.

METHODS

In a population-based birth cohort [The Western Australian Pregnancy Cohort (Raine) Study], total, externalising and internalising behaviour problems (domain-specific T≥60) were calculated from parent-reported Child Behavior Checklist at ages 2, 5, 8, 10 and 14 years. At age 17 years, 1200 (49% male) participants reported sexual and substance use activity Results: For both genders, those with earlier externalising behaviour problems were more likely to be sexually active (oral sex or sexual intercourse) by age 17 years. Males with childhood externalising behaviour problems were more likely to have multiple sexual partners by age 17 years than those without such problems [adjusted odds ratio (aOR) 2.96, 95% confidence interval (CI) 1.49-5.86]. Females with childhood externalising behaviour problems were more likely to have had unwanted sex (aOR 1.91, 95% CI 1.04-3.53). Externalising behaviour problems were associated with substance use for both genders. No association was found between internalising behaviour problems and risky behaviour.

CONCLUSIONS

Externalising behaviour problems from as early as 5 years old in boys and 8 years old in girls predict a range of risky sexual behaviour in adolescence, which has important implications for targeting interventions in adolescence.

Comparing adolescent and parent reports of externalizing problems: A longitudinal population-based study

Adolescent and parent reports of adolescent mental health problems often correlate poorly, and understanding this discrepancy has clinical importance. Yet contextual factors have only been inconsistently explained. At the 14- and 17-year follow-ups of the Western Australian Pregnancy Cohort (Raine) Study, 1,596 parent-child dyads completed the parent-reported Child Behaviour Checklist (CBCL) and the adolescent-rated Youth Self-Report (YSR). Maternal, family, adolescent, and parent factors were examined as potential predictors of discrepancies. When adolescent YSR scores were in the clinical range but parents' CBCL ratings were not, adolescents were more likely to report alcohol intoxication in the last 6 months, illicit drug use, low school motivation, and depression. When parents reported externalizing behaviour in the clinical range but adolescents did not, the characteristics associated with this were a younger maternal age, receiving social security benefit, stress related to parenting, depression, and poor family functioning. These new results will inform clinical management and research with adolescents who present with behavioural disorders. Statement of contribution What is already known on this subject? We know that adolescent and parent reports of adolescent mental health problems often correlate poorly, but little is known about which contextual factors lead to disagreement. Understanding the factors that influence agreement is clinically relevant for predicting and identifying externalizing behavioural disorders. This is a large-scale study with the ability to assess the impact of numerous psychosocial factors on instrument disagreement. What the present study adds We found that substance use, depression and low school motivation impacted on discrepancy in externalizing behaviour scores for 14-year-old male adolescents and their parents. Parental depression, stress, low family income, and family dysfunction also led to a higher likelihood of discrepancy in scores.

Severe lower limb cellulitis: defining the epidemiology and risk factors for primary episodes in a population-based case-control study

OBJECTIVE

To describe the epidemiology and risk factors for primary episodes of severe lower leg cellulitis (LLC).

METHODS

This was a longitudinal cohort study using state-wide data linkage of adults presenting to Western Australian (WA) hospitals with a first ever LLC from January 2002 to December 2013. The study aimed at determining risk factors, medical records from the index patient, together with comparable data from controls matched by age, sex, postcode, and month of admission.

RESULTS

During the period, 36 276 patients presented with their first episode of LLC. The incidence increased by 4.7% per annum, reaching 204.8 (95% CI 198.6-211.1) per 100 000 population by December 2013. Analysis of 29 062 case-control pairs showed several conditions with lower limb pathology were independently associated with LLC, including varicose veins (AOR 2.95, 95% CI 2.50-3.48, p < 0.001), lymphoedema (AOR 2.65, 95% CI 1.71-4.10, p < 0.001), tinea pedis (AOR 3.05, 95% CI 1.45-6.42, p 0.003), and saphenous vein harvest during coronary artery bypass grafting (AOR 1.74, 95% CI 1.32-2.30, p < 0.001). Also associated with LLC was obesity (AOR 2.05, 95% CI 1.82-2.31, p < 0.001), renal disease (AOR 1.28, 95% CI 1.14-1.44, p < 0.001), rheumatologic conditions (AOR 2.12, 95% CI 1.72-2.60, p < 0.001), hemiplegia/paraplegia (AOR 1.31, 95% CI 1.13-1.52, p < 0.001), and liver disease (AOR 1.77, 95% CI 1.51-2.06, p < 0.001).

CONCLUSIONS

LLC presents a major burden to the health sector and is increasing with an ageing population. Given the high rates of recurrence, long-term morbidity, and economic impact, efforts to reduce primary episodes should be incorporated into the infectious diseases and healthy ageing research agenda.

Epidemiology and risk factors for recurrent severe lower limb cellulitis: a longitudinal cohort study

OBJECTIVE

To describe the epidemiology and risk factors for recurrence of severe lower leg cellulitis (LLC).

METHODS

A longitudinal cohort study using state-wide data of adults presenting with recurrent LLC following a primary episode occurring between January 2002 and December 2013. The incidence of recurrent LLC was estimated using the cumulative incidence function, accounting for mortality. Independent risk factors for recurrence were identified using Fine-Gray sub-distribution and Cox proportional hazards models.

RESULTS

Of 36 276 patients presenting with their first episode of LLC, 4598 had at least one recurrence during the follow-up period. The cumulative incidence of first, second, and third recurrences at 12 months since previous infection was 6.3% (95% CI 6.0-6.5), 17.2% (95% CI 16.1-18.4), and 29.4% (95% CI 26.8-31.9), respectively, and at 5 years was 13.9% (95% CI 13.5-14.3), 35.9% (95% CI 34.2-37.5), and 52.9% (95% CI 49.5-56.2), respectively. The length of hospitalization increased from 3 days for the primary episode to 4 and 5 days for first and all subsequent recurrences, respectively. Independent risk factors for recurrent LLC included age, ethnicity (Indigenous Australian), local factors relating to lower leg pathology, conditions that commonly result in peripheral oedema, and systemic conditions that may be associated with increased leg size.

CONCLUSIONS

LLC recurrences are frequent, and each episode increases the likelihood of subsequent recurrence and length of hospitalization. These data provide context and scope to develop workable and effective strategies to prevent secondary episodes for all cases of primary LLC.

International validation of the European Organisation for Research and Treatment of Cancer QLQ-BRECON23 quality-of-life questionnaire for women undergoing breast reconstruction

Background

The aim was to carry out phase 4 international field-testing of the European Organisation for Research and Treatment of Cancer (EORTC) breast reconstruction (BRECON) module. The primary objective was finalization of its scale structure. Secondary objectives were evaluation of its reliability, validity, responsiveness, acceptability and interpretability in patients with breast cancer undergoing mastectomy and reconstruction.

Methods

The EORTC module development guidelines were followed. Patients were recruited from 28 centres in seven countries. A prospective cohort completed the QLQ-BRECON15 before mastectomy and the QLQ-BRECON24 at 4–8 months after reconstruction. The cross-sectional cohort completed the QLQ-BRECON24 at 1–5 years after reconstruction, and repeated this 2–8 weeks later (test–retest reliability). All participants completed debriefing questionnaires.

Results

A total of 438 patients were recruited, 234 in the prospective cohort and 204 in the cross-sectional cohort. A total of 414 reconstructions were immediate, with a comparable number of implants (176) and donor-site flaps (166). Control groups comprised patients who underwent two-stage implant procedures (72, 75 per cent) or delayed reconstruction (24, 25 per cent). Psychometric scale validity was supported by moderate to high item-own scale and item-total correlations (over 0·5). Questionnaire validity was confirmed by good scale-to-sample targeting, and computable scale scores exceeding 50 per cent, except nipple cosmesis (over 40 per cent). In known-group comparisons, QLQ-BRECON24 scales and items differentiated between patient groups defined by clinical criteria, such as type and timing of reconstruction, postmastectomy radiotherapy and surgical complications, with moderate effect sizes. Prospectively, sexuality and surgical side-effects scales showed significant responsiveness over time (P &lt; 0·001). Scale reliability was supported by high Cronbach's α coefficients (over 0·7) and test–retest (intraclass correlation more than 0·8). One item (finding a well fitting bra) was excluded based on high floor/ceiling effects, poor test–retest and weak correlations in factor analysis (below 0·3), thus generating the QLQ-BRECON23 questionnaire.

Conclusion

The QLQ-BRECON23 is an internationally validated tool to be used alongside the EORTC QLQ-C30 (cancer) and QLQ-BR23 (breast cancer) questionnaires for evaluating quality of life and satisfaction after breast reconstruction.

Rheumatic Heart Disease Severity, Progression and Outcomes: A Multi-State Model

Background

Rheumatic heart disease (RHD) remains a disease of international importance, yet little has been published about disease progression in a contemporary patient cohort. Multi‐state models provide a well‐established method of estimating rates of transition between disease states, and can be used to evaluate the cost‐effectiveness of potential interventions. We aimed to create a multi‐state model for RHD progression using serial clinical data from a cohort of Australian patients.

Methods and Results

The Northern Territory RHD register was used to identify all Indigenous residents diagnosed with RHD between the ages of 5 and 24 years in the time period 1999–2012. Disease severity over time, surgeries, and deaths were evaluated for 591 patients. Of 96 (16.2%) patients with severe RHD at diagnosis, 50% had proceeded to valve surgery by 2 years, and 10% were dead within 6 years. Of those diagnosed with moderate RHD, there was a similar chance of disease regression or progression over time. Patients with mild RHD at diagnosis were the most stable, with 64% remaining mild after 10 years; however, 11.4% progressed to severe RHD and half of these required surgery.

Conclusions

The prognosis of young Indigenous Australians diagnosed with severe RHD is bleak; interventions must focus on earlier detection and treatment if the observed natural history is to be improved. This multi‐state model can be used to predict the effect of different interventions on disease progression and the associated costs.

Echocardiographic Screening for Rheumatic Heart Disease in Indigenous Australian Children: A Cost-Utility Analysis

BACKGROUND

Rheumatic heart disease (RHD) remains a leading cause of cardiovascular morbidity and mortality in children and young adults in disadvantaged populations. The emergence of echocardiographic screening provides the opportunity for early disease detection and intervention. Using our own multistate model of RHD progression derived from Australian RHD register data, we performed a cost-utility analysis of echocardiographic screening in indigenous Australian children, with the dual aims of informing policy decisions in Australia and providing a model that could be adapted in other countries.

METHODS AND RESULTS

We simulated the outcomes of 2 screening strategies, assuming that RHD could be detected 1, 2, or 3 years earlier by screening. Outcomes included reductions in heart failure, surgery, mortality, disability-adjusted life-years, and corresponding costs. Only a strategy of screening all indigenous 5- to 12-year-olds in half of their communities in alternate years was found to be cost-effective (incremental cost-effectiveness ratio less than AU$50 000 per disability-adjusted life-year averted), assuming that RHD can be detected at least 2 years earlier by screening; however, this result was sensitive to a number of assumptions. Additional modeling of improved adherence to secondary prophylaxis alone resulted in dramatic reductions in heart failure, surgery, and death; these outcomes improved even further when combined with screening.

CONCLUSIONS

Echocardiographic screening for RHD is cost-effective in our context, assuming that RHD can be detected ≥2 years earlier by screening. Our model can be adapted to any other setting but will require local data or acceptable assumptions for model parameters.

Prevalence of sensitization to 'improver' enzymes in UK supermarket bakers

BACKGROUND

Supermarket bakers are exposed not only to flour and alpha-amylase but also to other 'improver' enzymes, the nature of which is usually shrouded by commercial sensitivity. We aimed to determine the prevalence of sensitization to 'improver' enzymes in UK supermarket bakers.

METHODS

We examined the prevalence of sensitization to enzymes in 300 bakers, employed by one of two large supermarket bakeries, who had declared work-related respiratory symptoms during routine health surveillance. Sensitization was determined using radioallergosorbent assay to eight individual enzymes contained in the specific 'improver' mix used by each supermarket.

RESULTS

The prevalence of sensitization to 'improver' enzymes ranged from 5% to 15%. Sensitization was far more likely if the baker was sensitized also to either flour or alpha-amylase. The prevalence of sensitization to an 'improver' enzyme did not appear to be related to the concentration of that enzyme in the mix.

CONCLUSIONS

We report substantial rates of sensitization to enzymes other than alpha-amylase in UK supermarket bakers; in only a small proportion of bakers was there evidence of sensitization to 'improver mix' enzymes without sensitization to either alpha-amylase or flour. The clinical significance of these findings needs further investigation, but our findings indicate that specific sensitization in symptomatic bakers may not be identified without consideration of a wide range of workplace antigens.

Perceptual and cerebro-spinal responses to graded innocuous and noxious stimuli following aerobic exercise

AIM

The aim of this study was to evaluate the effect of aerobic exercise on perceptual and cerebro-spinal responses to graded electrocutaneous stimuli.

METHODS

The design comprised 2 x 30 min of cycling exercise at 30% and 70% of peak oxygen consumption (VO2 peak) on separate occasions in a counter-balanced order in 10 healthy participants. Assessment of nociceptive withdrawal reflex threshold (NWR-T), pain threshold (PT), and somatosensory evoked potentials (SEPs) to graded electrocutaneous stimuli were performed before and after exercise. Perceptual magnitude ratings and SEPs were compared at 30%PT, 60%PT, 100%PT before (Pre), 5 min after (Post1), and 15 min after (Post2) aerobic exercise.

RESULTS

There was no difference in the NWR-T and the PT following exercise at 30% and 70% of VO2 peak. ANOVA for the perceptual response within pooled electrocutaneous stimuli show a significant main effect for time (F2,18=5.41, P=0.01) but no difference for exercise intensity (F1,9=0.02, P=0.88). Within-subject contrasts reveal trend differences between 30%PT and 100%PT for Pre-Post1 (P=0.09) and Pre-Post2 (P=0.02). ANOVA for the SEPs peak-to-peak signal amplitude (N1-P1) show significant main effect for time (F2,18=4.04, P=0.04) but no difference for exercise intensity (F1,9=1.83, P=0.21). Pairwise comparisons for time reveal differences between Pre-Post1 (P=0.06) and Pre-Post2 (P=0.01). There was a significant interaction for SEPs N1-P1 between exercise intensity and stimulus intensity (F2,18=3.56, P=0.05).

CONCLUSION

These results indicate that aerobic exercise did not increase the electrocutaneous threshold for pain and the NWR-T. Aerobic exercise attenuated perceptual responses to innocuous stimuli and SEPs N1-P1 response to noxious stimuli.

Occupational asthma from tafenoquine in the pharmaceutical industry: implications for QSAR

We report occupational asthma and rhinitis in a formulation pharmacist, employed in the development of tafenoquine. Tafenoquine is a new anti-malarial drug in development; the pure drug substance has an asthma hazard index of zero and previously was not known to be a respiratory sensitizing agent. The implications of this finding for the refinement of quantitative structural analysis of asthmagenic chemicals are discussed.

Childhood behavior problems and age at first sexual intercourse: a prospective birth cohort study

BACKGROUND AND OBJECTIVES

Early first sexual intercourse (FSI) is a risk factor for unplanned teenage pregnancy, sexually transmitted infection, and adverse social, emotional, and physical health outcomes in adolescence and into adulthood. The aim of this study was to examine relationships between internalizing (eg, anxious/depressed, withdrawn) and externalizing (eg, delinquent, aggressive) behavior problems in childhood and age at FSI.

METHODS

We used a large, population-based birth cohort (The Western Australian Pregnancy Cohort [Raine] Study) to address this question. Child behavior was measured by using the Child Behavior Checklist collected from parents at ages 2, 5, 8, 10, and 14 and scores calculated for total, internalizing, and externalizing behavior problems. At age 17, 1200 participants reported sexual behavior.

RESULTS

Participants with clinically significant Child Behavior Checklist scores (T ≥ 60) were at increased risk for earlier first sexual intercourse (FSI) (<16 years). Adjusted odds ratios revealed that total and externalizing behavior problems from age 5 years onward significantly increased the risk of earlier FSI for boys. In girls, externalizing problems from age 10 years increased the risk for earlier FSI. Internalizing problems at ages 8 and 10 were significantly associated with early FSI for boys but not girls.

CONCLUSIONS

Externalizing behavior from as early as 5 in boys and 10 in girls is a significant risk factor for earlier age at FSI. Adolescent sexual health promotion should consider early intervention in children with behavior problems, particularly boys.

Age at menarche and age at first sexual intercourse: a prospective cohort study

OBJECTIVE

Younger age at menarche (AAM) may put girls at risk for earlier first sexual intercourse (FSI). Young age at FSI has far-reaching negative outcomes. We describe the longitudinal relationship between AAM and FSI in a large prospective birth cohort.

METHODS

AAM was collected from 554 girls from the Western Australia (Raine) Pregnancy Cohort Study, prospectively from age 10 or retrospectively at age 14. Age at FSI was collected at ages 17 and 20. Cox regression models describe likelihood of FSI by age and years since menarche for younger (<12 years) and older (≥14 years) AAM relative to average AAM (12-13 years).

RESULTS

Girls with younger AAM and average AAM were equally likely to have FSI by age 16 (adjusted hazard ratio [aHR]: 0.90 [95% confidence interval (CI): 0.60-1.35]). FSI by age 16 was less likely among girls with older AAM than those with average AAM (aHR: 0.35 [95% CI: 0.17-0.72]). Girls with younger AAM had a longer median interval between menarche and FSI than girls with average AAM (5.0 years [interquartile range: 4.4-8.5 years] vs 3.7 years [interquartile range: 2.4-5.3 years]). Those with younger AAM were less likely to report FSI within 4 years of menarche than those with average AAM (0-2 years aHR: 0.04 [95% CI: 0.01-0.31]; 2-4 years aHR: 0.36 [95% CI: 0.23-0.55]). By age 20, 429 girls (77.4%) reported FSI.

CONCLUSIONS

Younger AAM was not a risk factor for younger age at FSI in this cohort.

Cold-water immersion decreases cerebral oxygenation but improves recovery after intermittent-sprint exercise in the heat

This study examined the effects of post-exercise cooling on recovery of neuromuscular, physiological, and cerebral hemodynamic responses after intermittent-sprint exercise in the heat. Nine participants underwent three post-exercise recovery trials, including a control (CONT), mixed-method cooling (MIX), and cold-water immersion (10 °C; CWI). Voluntary force and activation were assessed simultaneously with cerebral oxygenation (near-infrared spectroscopy) pre- and post-exercise, post-intervention, and 1-h and 24-h post-exercise. Measures of heart rate, core temperature, skin temperature, muscle damage, and inflammation were also collected. Both cooling interventions reduced heart rate, core, and skin temperature post-intervention (P < 0.05). CWI hastened the recovery of voluntary force by 12.7 ± 11.7% (mean ± SD) and 16.3 ± 10.5% 1-h post-exercise compared to MIX and CONT, respectively (P < 0.01). Voluntary force remained elevated by 16.1 ± 20.5% 24-h post-exercise after CWI compared to CONT (P < 0.05). Central activation was increased post-intervention and 1-h post-exercise with CWI compared to CONT (P < 0.05), without differences between conditions 24-h post-exercise (P > 0.05). CWI reduced cerebral oxygenation compared to MIX and CONT post-intervention (P < 0.01). Furthermore, cooling interventions reduced cortisol 1-h post-exercise (P < 0.01), although only CWI blunted creatine kinase 24-h post-exercise compared to CONT (P < 0.05). Accordingly, improvements in neuromuscular recovery after post-exercise cooling appear to be disassociated with cerebral oxygenation, rather reflecting reductions in thermoregulatory demands to sustain force production.