Risk-based lung cancer screening performance in a universal healthcare setting

Globally, lung cancer is the leading cause of cancer death. Previous trials demonstrated that low-dose computed tomography lung cancer screening of high-risk individuals can reduce lung cancer mortality by 20% or more. Lung cancer screening has been approved by major guidelines in the United States, and over 4,000 sites offer screening. Adoption of lung screening outside the United States has, until recently, been slow. Between June 2017 and May 2019, the Ontario Lung Cancer Screening Pilot successfully recruited 7,768 individuals at high risk identified by using the PLCOm2012noRace lung cancer risk prediction model. In total, 4,451 participants were successfully screened, retained and provided with high-quality follow-up, including appropriate treatment. In the Ontario Lung Cancer Screening Pilot, the lung cancer detection rate and the proportion of early-stage cancers were 2.4% and 79.2%, respectively; serious harms were infrequent; and sensitivity to detect lung cancers was 95.3% or more. With abnormal scans defined as ones leading to diagnostic investigation, specificity was 95.5% (positive predictive value, 35.1%), and adherence to annual recall and early surveillance scans and clinical investigations were high (>85%). The Ontario Lung Cancer Screening Pilot provides insights into how a risk-based organized lung screening program can be implemented in a large, diverse, populous geographic area within a universal healthcare system.

Integrating Smoking Cessation Into Low-Dose Computed Tomography Lung Cancer Screening: Results of the Ontario, Canada Pilot

INTRODUCTION

Low-dose computed tomography screening in high-risk individuals reduces lung cancer mortality. To inform the implementation of a provincial lung cancer screening program, Ontario Health undertook a Pilot study, which integrated smoking cessation (SC).

METHODS

The impact of integrating SC into the Pilot was assessed by the following: rate of acceptance of a SC referral; proportion of individuals who were currently smoking cigarettes and attended a SC session; the quit rate at 1 year; change in the number of quit attempts; change in Heaviness of Smoking Index; and relapse rate in those who previously smoked.

RESULTS

A total of 7768 individuals were recruited predominantly through primary care physician referral. Of these, 4463 were currently smoking and were risk assessed and referred to SC services, irrespective of screening eligibility: 3114 (69.8%) accepted referral to an in-hospital SC program, 431 (9.7%) to telephone quit lines, and 50 (1.1%) to other programs. In addition, 4.4% reported no intention to quit and 8.5% were not interested in participating in a SC program. Of the 3063 screen-eligible individuals who were smoking at baseline low-dose computed tomography scan, 2736 (89.3%) attended in-hospital SC counseling. The quit rate at 1 year was 15.5% (95% confidence interval: 13.4%-17.7%; range: 10.5%-20.0%). Improvements were also observed in Heaviness of Smoking Index (p < 0.0001), number of cigarettes smoked per day (p < 0.0001), time to first cigarette (p < 0.0001), and number of quit attempts (p < 0.001). Of those who reported having quit within the previous 6 months, 6.3% had resumed smoking at 1 year. Furthermore, 92.7% of the respondents reported satisfaction with the hospital-based SC program.

CONCLUSIONS

On the basis of these observations, the Ontario Lung Screening Program continues to recruit through primary care providers, to assess risk for eligibility using trained navigators, and to use an opt-out approach to referral for cessation services. In addition, initial in-hospital SC support and intensive follow-on cessation interventions will be provided to the extent possible.

Reporting of tobacco use and tobacco-related analyses in cancer cooperative group clinical trials: a systematic scoping review

BACKGROUND

Continued smoking after a diagnosis of cancer negatively impacts cancer outcomes, but the impact of tobacco on newer treatments options is not well established. Collecting and evaluating tobacco use in clinical trials may advance understanding of the consequences of tobacco use on treatment modalities, but little is known about the frequency of reporting and analysis of tobacco use in cancer cooperative clinical trial groups.

PATIENTS AND METHODS

A comprehensive literature search was conducted to identify cancer cooperative group clinical trials published from January 2017-October 2019. Eligible studies evaluated either systemic and/or radiation therapies, included ≥100 adult patients, and reported on at least one of: overall survival, disease/progression-free survival, response rates, toxicities/adverse events, or quality-of-life.

RESULTS

A total of 91 studies representing 90 trials met inclusion criteria with trial start dates ranging from 1995 to 2015 with 14% involving lung and 5% head and neck cancer patients. A total of 19 studies reported baseline tobacco use; 2 reported collecting follow-up tobacco use. Seven studies reported analysis of the impact of baseline tobacco use on clinical outcomes. There was significant heterogeneity in the reporting of baseline tobacco use: 7 reported never/ever status, 10 reported never/ex-smoker/current smoker status, and 4 reported measuring smoking intensity. None reported verifying smoking status or second-hand smoke exposure. Trials of lung and head and neck cancers were more likely to report baseline tobacco use than other disease sites (83% versus 6%, P < 0.001).

CONCLUSIONS

Few cancer cooperative group clinical trials report and analyze trial participants' tobacco use. Significant heterogeneity exists in reporting tobacco use. Routine standardized collection and reporting of tobacco use at baseline and follow-up in clinical trials should be implemented to enable investigators to evaluate the impact of tobacco use on new cancer therapies.

Reporting of tobacco use and impact on outcomes in cancer cooperative group clinical trials: A systematic scoping review

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Background: Continued smoking after a diagnosis of cancer negatively impacts cancer outcomes but the impact of tobacco on many innovative treatments has not yet been well established. Collecting and evaluating tobacco use in cancer clinical trials may advance understanding of the consequences of tobacco use on specific treatment modalities. We performed a systematic scoping review of the frequency of reporting and analysis of tobacco use in clinical trials run by cancer cooperative clinical trial groups. Methods: A comprehensive literature search was conducted to identify cancer cooperative group clinical trials published from January 2017 to October 2019 using Medline, Epub Ahead of Print and In-Process & Other Non-Indexed Citations, Embase, Cochrane Central Register of Controlled Trials using OvidSP. Eligible studies evaluated either systemic and/or radiation therapies, involved at least one cancer cooperative group, included > 100 adult patients and reported on at least one primary or secondary endpoint, which included overall survival (OS), disease/progression-free survival (DFS/PFS), response rates, toxicities/adverse events, or quality of life (QoL). Secondary analyses of previously published trials were excluded. Results: Among 14843 identified studies, 91 studies representing 90 trials met inclusion criteria. 24% were phase II trials, 2% phase II/III and 74% phase III. Trial start dates ranged from 1995-2015 with most (29%) between 2007-2008; median trial sample size was 406 (range: 100-4994); 86% involved systematic therapy, 35% involved radiation; 14% were lung and 5% were head and neck trials. 51% of trials had a curative intent, 33% were palliative and 16% involved hematologic cancers. 74 studies reported on OS, 73 DFS/PFS, and 88 toxicity/QoL. 19 studies reported baseline tobacco use information, while two reported collecting follow-up tobacco use. Of those collecting baseline tobacco use, only 7 reported any analysis of the impact of tobacco on clinical outcomes. There was significant heterogeneity in the reporting of baseline tobacco use: 5 reported never/ever status, 10 reported never/ex-smoker/current smoker status; 4 reported some measure of smoking intensity; none reported on verifying smoking status or second hand smoke exposure. Trials of tobacco related (lung and head and neck) cancers were more likely to report baseline tobacco use compared to non-tobacco related cancers (83% vs 6% p < 0.001). Conclusions: Few cancer cooperative group clinical trials report and analyze trial participants’ baseline tobacco use, and even fewer collect follow up information. Significant heterogeneity exists in reporting tobacco use. Routine standardized collection and reporting of tobacco use, both at baseline and follow up in clinical trials, should be implemented to enable investigators to evaluate the clinical impact of tobacco use on new cancer therapies.

Socio-demographic factors related to binge drinking in Ontario

BACKGROUND

Alcohol consumption has been linked to harmful health short and long-term outcomes. An analysis of socio-demographic factors related to binge drinking may help to identify groups at risk and provide primary health care providers an opportunity to assist members of those groups. In this study, we examined socio-demographic factors associated with binge drinking in Ontario, Canada.

METHODS

This analysis used data from a cross-sectional survey of Ontario adults (ages 19 and older) for the 2015-2017 period. Bivariate and multivariate adjusted analyses examined the association between binge drinking and socio-demographic factors. These analyses were also stratified by sex.

RESULTS

Increased alcohol binge drinking was associated with several socio-demographic factors including younger age groups, lower educational attainment, lower household income quintile, having immigrated to Canada within past 10 years, being male, reporting poorer mental health, being single, living in rural areas, and being unemployed. No differences were noted by households with or without children or by sexual orientation. Many of the factors associated with binge drinking remained significant when stratified by sex.

DISCUSSION

These findings suggest that several socio-demographic factors are associated with binge drinking. These can be helpful indicators for decision makers responsible for programs and policies aimed at reducing alcohol binge drinking, and for primary care providers, who in a brief intervention can screen for binge drinking and support those individuals by connecting them with local resources to reduce their harmful alcohol consumption habits.

Association between Cancer Risk and Behaviors Adherent to Cancer Prevention Recommendations in Ontario, Canada

PURPOSE

In 2007, the World Cancer Research Fund (WCRF) and American Institute for Cancer Research (AICR) published several diet and physical activity recommendations to reduce cancer risk. Our objective was to examine the association between self-reported behaviors consistent with the WCRF/AICR recommendations and the risk of developing any cancer and colorectal cancer in Ontario.

METHOD

111,139 Ontarians who completed the Canadian Community Health Survey (2000-2008) were linked to the Ontario Cancer Registry to determine whether they were diagnosed with cancer. Their responses were used to assess behaviors consistent with 4 WCRF/AICR recommendations (body fatness, physical activity, vegetable and fruit consumption, and alcoholic drinks). Multivariate Cox proportional hazard regression models were used to assess the association between adherence to the 4 WCRF/AICR recommendations and subsequent cancer risk.

RESULTS

Among the 111,139 participants, 8,942 (8%) were diagnosed with cancer with a mean follow-up of 9.6 years. Compared to not meeting any of the selected WCRF/AICR recommendations (composite score, 0), participants who were most adherent to the selected WCRF/AICR recommendations (composite score, 4) were 31% less likely to develop any cancer (HR, 0.69; 95% CI, 0.51-0.92) and were 61% less likely to develop colorectal cancer (HR, 0.39; 95% CI, 0.20-0.77) after adjusting for some potential confounding factors. When stratified by sex, the associations remained statistically significant for men, but not for women. In addition, increasing vegetable and fruit consumption, having lower body fatness, and decreasing alcohol consumption were each associated with reduced risk of both any cancer and colorectal cancer.

CONCLUSION

Healthy behaviors consistent with select WCRF/AICR recommendations were associated with a decreased risk of developing any cancer and colorectal cancer among this Ontario cohort.

Comprehensive Cancer Survival by Neighborhood-Level Income in Ontario, Canada, 2006-2011

BACKGROUND

Cancer survival statistics can provide a means to assess the effectiveness of the cancer care system, including early detection strategies, the quality of clinical care, and disease management. Disparities in cancer survival (for instance, by neighborhood-level income) persist in Ontario, Canada despite the existence of a universal health care system. Lower income has been associated with an increased incidence of cancer and worsened survival.

PURPOSE

This project aims to analyze and report on relative survival to provide a mechanism for understanding the level of equity within Ontario's cancer care system.

METHODS

Age-standardized relative survival ratios (ARSRs) by cancer type and age group were estimated for 229,934 Ontario adults aged 15-99 years diagnosed between 2006 and 2011 with 1 of 9 cancer types (stomach, colorectal, liver, lung, breast, cervical, ovarian, prostate, and leukemia) using a complete survival analysis. Using the Pohar-Perme estimator, the 1-, 3- and 5-year ARSRs with 95% confidence intervals were calculated by patients' neighborhood-level income quintile. Estimates were age-standardized using the International Cancer Survival Standard weights.

RESULTS

Fifty-four relative survival trend curves were developed covering 9 cancers by neighborhood-level income for Ontarians in 5 different age groups and all age groups combined. Disparities in cancer survival were observed between income groups and across age groups and different cancer types in Ontario. For most cancer types and age groups, survival was higher in higher income groups, but this trend was not consistently observed in adolescents and young adults aged 15-44 years.

CONCLUSIONS

Disparities in cancer survival persist in Ontario across income groups. Relative survival was significantly higher for higher (Q4 or Q5) compared to lower (Q1 or Q2) neighborhood-level income populations for most cancer types and age groups. Adolescents and young adults with cancer are a small and unique group of patients in terms of the biology of their cancers and their cancer journey, thereby making the patterns of survival disparities observed in this age group more complicated to interpret. Further examination of factors contributing to these disparities is crucial to eliminate survival disparities, reduce premature deaths, and improve cancer survival in Ontario.

Impact of smoking on health system costs among cancer patients in a retrospective cohort study in Ontario, Canada

OBJECTIVE

Smoking is the main modifiable cancer risk factor. The objective of this study was to examine the impact of smoking on health system costs among newly diagnosed adult patients with cancer. Specifically, costs of patients with cancer who were current smokers were compared with those of non-smokers from a publicly funded health system perspective.

METHODS

This population-based cohort study of patients with cancer used administrative databases to identify smokers and non-smokers (1 April 2014-31 March 2016) and their healthcare costs in the 12-24 months following a cancer diagnosis. The health services included were hospitalisations, emergency room visits, drugs, home care services and physician services (from the time of diagnosis onwards). The difference in cost (ie, incremental cost) between patients with cancer who were smokers and those who were non-smokers was estimated using a generalised linear model (with log link and gamma distribution), and adjusted for age, sex, neighbourhood income, rurality, cancer site, cancer stage, geographical region and comorbidities.

RESULTS

This study identified 3606 smokers and 14 911 non-smokers. Smokers were significantly younger (61 vs 65 years), more likely to be male (53%), lived in poorer neighbourhoods, had more advanced cancer stage,and were more likely to die within 1 year of diagnosis, compared with non-smokers. The regression model revealed that, on average, smokers had significantly higher monthly healthcare costs ($5091) than non-smokers ($4847), p<0.05.

CONCLUSIONS

Smoking status has a significant impact on healthcare costs among patients with cancer. On average, smokers incurred higher healthcare costs than non-smokers. These findings provide a further rationale for efforts to introduce evidence-based smoking cessation programmes as a standard of care for patients with cancer as they have the potential not only to improve patients' outcomes but also to reduce the economic burden of smoking on the healthcare system.

Implementing smoking cessation within cancer treatment centres and potential economic impacts

Background

Although the health benefits of smoking cessation in newly diagnosed cancer patients are well established, systematic efforts to help cancer patients stop smoking have rarely been implemented in cancer centres.

Methods

Starting in 2012, the 14 regional cancer centres overseen by Cancer Care Ontario in the province of Ontario, Canada began to screen ambulatory cancer patients for their smoking status, to provide smokers with advice on the health benefits of quitting and to offer referral to smoking cessation services. Multiple initiatives were undertaken to educate healthcare providers and patients on the health benefits of cessation. Critical to the success of the initiative was strong leadership from Cancer Care Ontario executives and regional vice presidents, advice from an advisory committee of smoking cessation experts, engagement of regional champions and support from a provincial secretariat. The quarterly review of performance metrics was an important driver of change.

Results

Most cancer centres now screen in excess of 75% of ambulatory patients but rates for the acceptance of a referral to smoking cessation services remain low (less than 25%). Introduction of an opt-out referral process appears to increase referral acceptance. Economic analyses suggest that smoking cessation is cost-effective in a cancer centre environment.

Conclusions

Although there are barriers to the implementation of smoking cessation in cancer centres, it is possible to change the culture to one in which smoking cessation is considered part of high-quality treatment.

Economic evaluation of smoking cessation in Ontario's regional cancer programs

Quitting smoking after a diagnosis of cancer results in greater response to treatment and decreased risk of disease recurrence and second primary cancers. The objective of this study was to evaluate the potential cost-effectiveness of two smoking cessation approaches: the current basic smoking cessation program consisting of screening for tobacco use, advice, and referral; and a best practice smoking cessation program that includes the current basic program with the addition of pharmacological therapy, counseling, and follow-up. A Markov model was constructed that followed 65-year-old smokers with cancer over a lifetime horizon. Transition probabilities and mortality estimates were obtained from the published literature. Costs were obtained from standard costing sources in Ontario and reports. Probabilistic and deterministic sensitivity analyses were conducted to address parameter uncertainties. For smokers with cancer, the best practice smoking cessation program was more effective and more costly than the basic smoking cessation program. The incremental cost-effectiveness ratio of the best practice smoking cessation program compared to the basic smoking cessation program was $3367 per QALY gained and $5050 per LY gained for males, and $2050 per QALY gained and $4100 per LY gained for females. Results were most sensitive to the hazard ratio of mortality for former and current smokers, the probability of quitting smoking through participation in the program and smoking-attributable costs. The study results suggested that a best practice smoking cessation program could be a cost-effective option. These findings can support and guide implementation of smoking cessation programs.

The Ontario Food and Nutrition Strategy: identifying indicators of food access and food literacy for early monitoring of the food environment

INTRODUCTION

To address challenges Canadians face within their food environments, a comprehensive, multistakeholder, intergovernmental approach to policy development is essential. Food environment indicators are needed to assess population status and change. The Ontario Food and Nutrition Strategy (OFNS) integrates the food, agriculture and nutrition sectors, and aims to improve the health of Ontarians through actions that promote healthy food systems and environments. This report describes the process of identifying indicators for 11 OFNS action areas in two strategic directions (SDs): Healthy Food Access, and Food Literacy and Skills.

METHODS

The OFNS Indicators Advisory Group used a five-step process to select indicators: (1) potential indicators from national and provincial data sources were identified; (2) indicators were organized by SD, action area and data type; (3) selection criteria were identified, pilot tested and finalized; (4) final criteria were applied to refine the indicator list; and (5) indicators were prioritized after reapplication of selection criteria.

RESULTS

Sixty-nine potential indicators were initially identified; however, many were individual-level rather than system-level measures. After final application of the selection criteria, one individual-level indicator and six system-level indicators were prioritized in five action areas; for six of the action areas, no indicators were available.

CONCLUSION

Data limitations suggest that available data may not measure important aspects of the food environment, highlighting the need for action and resources to improve system-level indicators and support monitoring of the food environment and health in Ontario and across Canada.

The Development of a Provincial Food and Nutrition Strategy through Cross-Sector Collaboration

A whole-system perspective is critical in efforts to create a healthy population and a productive, equitable, and sustainable food system. In 2009, the Ontario Collaborative Group on Healthy Eating and Physical Activity undertook a bold initiative to develop a comprehensive provincial strategy encompassing the entire food system. The Ontario Food and Nutrition Strategy was shaped through extensive consultation with diverse stakeholders. This strategy identified strategic directions and priority actions for productive, equitable, and sustainable food systems intended to promote the health and well-being of all Ontarians. Paramount to the strategy is a collaborative governance mechanism allowing for a cross-government, multistakeholder coordinated approach to food policy development. Key actors participated in a collective impact process to develop a theory of change and potential governance model. Different models for collaborative work were examined and a governance model for a multistakeholder coordinated provincial mechanism was proposed. Lessons learned from this process will inform others involved in food systems work at the provincial, regional, or local level and may pave the way towards successful inter-sectoral action on priority recommendations geared towards improved nutrition-related and food systems outcomes.

Lessons learned implementing a province-wide smoking cessation initiative in Ontario’s cancer centres

Purpose A large body of evidence clearly shows that cancer patients experience significant health benefits with smoking cessation. Cancer Care Ontario, the provincial agency responsible for the quality of cancer services in Ontario, has undertaken a province-wide smoking cessation initiative. The strategies used, the results achieved, and the lessons learned are the subject of the present article.Methods Evidence related to the health benefits of smoking cessation in cancer patients was reviewed. A steering committee developed a vision statement for the initiative, created a framework for implementation, and made recommendations for the key elements of the initiative and for smoking cessation best practices.Results New ambulatory cancer patients are being screened for their smoking status in each of Ontario’s 14 regional cancer centres. Current or recent smokers are advised of the benefits of cessation and are directed to smoking cessation resources as appropriate. Performance metrics are captured and used to drive improvement through quarterly performance reviews and provincial rankings of the regional cancer centres.Conclusions Regional smoking cessation champions, commitment from Cancer Care Ontario senior leadership, a provincial secretariat, and guidance from smoking cessation experts have been important enablers of early success. Data capture has been difficult because of the variety of information systems in use and non-standardized administrative and clinical processes. Numerous challenges remain, including increasing physician engagement; obtaining funding for key program elements, including in-house resources to support smoking cessation; and overcoming financial barriers to access nicotine replacement therapy. Future efforts will focus on standardizing processes to the extent possible, while tailoring the approaches to the populations served and the resources available within the individual regional cancer programs.

Lessons learned implementing a province-wide smoking cessation initiative in Ontario's cancer centres

PURPOSE

A large body of evidence clearly shows that cancer patients experience significant health benefits with smoking cessation. Cancer Care Ontario, the provincial agency responsible for the quality of cancer services in Ontario, has undertaken a province-wide smoking cessation initiative. The strategies used, the results achieved, and the lessons learned are the subject of the present article.

METHODS

Evidence related to the health benefits of smoking cessation in cancer patients was reviewed. A steering committee developed a vision statement for the initiative, created a framework for implementation, and made recommendations for the key elements of the initiative and for smoking cessation best practices.

RESULTS

New ambulatory cancer patients are being screened for their smoking status in each of Ontario's 14 regional cancer centres. Current or recent smokers are advised of the benefits of cessation and are directed to smoking cessation resources as appropriate. Performance metrics are captured and used to drive improvement through quarterly performance reviews and provincial rankings of the regional cancer centres.

CONCLUSIONS

Regional smoking cessation champions, commitment from Cancer Care Ontario senior leadership, a provincial secretariat, and guidance from smoking cessation experts have been important enablers of early success. Data capture has been difficult because of the variety of information systems in use and non-standardized administrative and clinical processes. Numerous challenges remain, including increasing physician engagement; obtaining funding for key program elements, including in-house resources to support smoking cessation; and overcoming financial barriers to access nicotine replacement therapy. Future efforts will focus on standardizing processes to the extent possible, while tailoring the approaches to the populations served and the resources available within the individual regional cancer programs.

Meeting patient and provider eTechnology needs: A provincial approach

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Background: Cancer Care Ontario is the government agency responsible for improving cancer services across Ontario, and for implementing standards such as quality care, benchmarking and system navigation. In this role, a provincial information management and information technology (IM/IT) strategy across the patient continuum of care is essential to achieve the goal of improving the performance of the healthcare system and enhancing quality of care. Methods: Cancer Care Ontario developed a standardized approach for an IM/IT strategy through clinical engagement, needs assessment, gap analysis, clinical standardization influencing product build, usability testing, change management and post-implementation evaluation. Results: See table below. Conclusions: Ontario’s strategy for IM/IT initiatives includes a repertoire of eTools for system, patient and clinician level end user needs. An ongoing evaluation strategy including real-time patient experience measures will further strengthen the approach. [Table: see text]

The hydroxyl radical in lens nuclear cataractogenesis

Cataract is the major cause of blindness; the most common form is age-related, or senile, cataract. The reasons for the development of cataract are unknown. Here we demonstrate that nuclear cataract is associated with the extensive hydroxylation of protein-bound amino acid residues, which increases with the development of cataract by up to 15-fold in the case of DOPA. The relative abundance of the oxidized amino acids in lens protein (assessed per parent amino acid) is DOPA > o- and m-tyrosine > 3-hydroxyvaline, 5-hydroxyleucine > dityrosine. Nigrescent cataracts, in which the normally transparent lens becomes black and opaque, contain the highest level of hydroxylated amino acids yet observed in a biological tissue: for example, per 1000 parent amino acid residues, DOPA, 15; 3-hydroxyvaline, 0.3; compared with dityrosine, 0.05. The products include representatives of the hydroperoxide and DOPA pathways of protein oxidation, which can give rise to secondary reactive species, radical and otherwise. The observed relative abundance corresponds closely with that of products of hydroxyl radical or metal-dependent oxidation of isolated proteins, and not with the patterns resulting from hypochlorite or tyrosyl-radical oxidation. Although very little light in the 300-400-nm range passes the cornea and the filter compounds of the eye, we nevertheless also demonstrate that photoxidation of lens proteins with light of 310 nm, the part of the spectrum in which protein aromatic residues have residual absorbance, does not give rise to the hydroxylated aliphatic amino acids. Thus the post-translational modification of crystallins by hydroxyl radicals/Fenton systems seems to dominate their in vivo oxidation, and it could explain the known features of such nuclear cataractogenesis.

gamma-Glutamylglutamine identified in plasma and cerebrospinal fluid from hyperammonaemic patients

gamma-Glutamylglutamine has been identified in plasma and cerebrospinal fluid. Preparative high voltage electrophoresis was used to isolate the compound from two to three ml of sample. Analysis of archival material from eight patients with urea cycle disorders showed that plasma gamma-glutamylglutamine was 20-214 mumol/l when the plasma glutamine was greater than 1,000 mumol/l and that the relationship was strongly positive (P less than 0.0005). Plasma gamma-glutamylglutamine concentration was also raised in one patient with secondary hyperammonaemia, but not in three other cases, one of whom had a plasma glutamine of 10,000 mumol/l. Cerebrospinal fluid from the last patient contained 97 mumol/l of gamma-glutamylglutamine. Samples of cerebrospinal fluid from two patients with urea cycle disorders were available and the gamma-glutamylglutamine levels were 203 and 313 mumol/l. gamma-Glutamylglutamine and 5-oxoproline concentrations were not significantly increased in urine from any of these patients.

Exercise-induced purpura

A 11-year-old boy developed purpura on the back and chest on more than 5 occasions following vigorous exercise. This eruption should be added to the list of differential diagnosis of the dermatosis experienced by athletes.

Improved procedure for the anion-exchange isolation of urinary organic acids

DEAE-Sephadex equilibrated in 0.5 M triethylammonium acetate is suitable for the quantitative isolation of lactonisable organic acids. Mono-, di- and tricarboxylic acids can be eluted sequentially from DEAE-Sephadex by the use of 0.5 M triethylamine, 0.5 M triethylamine--0.1 M acetic acid, and 1.5 M pyridinium acetate.