Urine high-risk human papillomavirus testing as an alternative to routine cervical screening: A comparative diagnostic accuracy study of two urine collection devices using a randomised study design trial

OBJECTIVE

To evaluate the sensitivity of human papillomavirus (HPV) tested urine to detect high-grade cervical precancer (cervical intraepithelial neoplasia grade 2+ [CIN2+]) using two urine collection devices.

DESIGN

Randomised controlled trial.

SETTING

St Mary's Hospital, Manchester, UK.

POPULATION

Colposcopy attendees with abnormal cervical screening; a total of 480 participants were randomised. Matched urine and cervical samples were available for 235 and 230 participants using a first-void urine (FVU)-collection device and standard pot, respectively.

METHODS

Urine was self-collected and mixed with preservative - randomised 1:1 to FVU-collection device (Novosanis Colli-pee® 10 mL with urine conservation medium [UCM]) or standard pot. Matched clinician-collected cervical samples were taken before colposcopy. HPV testing used Roche cobas® 8800. A questionnaire evaluated urine self-sampling acceptability.

MAIN OUTCOME MEASURES

The primary outcome measured sensitivity of HPV-tested urine (FVU-collection device and standard pot) for CIN2+ detection. Secondary outcomes compared HPV-tested cervical and urine samples for CIN2+ and evaluated the acceptability of urine self-sampling.

RESULTS

Urine HPV test sensitivity for CIN2+ was higher with the FVU-collection device (90.3%, 95% CI 83.7%-94.9%, 112/124) than the standard pot (73.4%, 95% CI 64.7%-80.9%, 91/124, p = 0.0005). The relative sensitivity of FVU-device-collected urine was 0.92 (95% CI 0.87-0.97, pMcN = 0.004) compared with cervical, considering that all women were referred after a positive cervical HPV test. Urine-based sampling was acceptable to colposcopy attendees.

CONCLUSIONS

Testing of FVU-device-collected urine for HPV was superior to standard-pot-collected urine in colposcopy attendees and has promising sensitivity for CIN2+ detection. General population HPV testing of FVU-device-collected urine will establish its clinical performance and acceptability as an alternative to routine cervical screening.

A comparison of the carbon footprint of alternative sampling approaches for cervical screening in the UK: A descriptive study

OBJECTIVE

To understand whether self-sampling can reduce carbon emissions (CO2 e) from the NHS cervical screening programme (NHSCSP) by comparing the carbon footprint of three sampling strategies: routine cervical sampling, vaginal self-sampling and first-void (FV) urine collection.

DESIGN

Descriptive study.

SETTING

National Health Service (NHS), United Kingdom (UK).

POPULATION OR SAMPLE

Patients aged 25-64 years eligible for cervical screening in the UK.

METHODS

A carbon footprint analysis was undertaken for three cervical screening sampling approaches, from point of invitation to screening through to preparation for transport to the laboratory for HPV testing. A combination of primary and secondary data were used, with a bottom-up approach applied to collection of primary data.

MAIN OUTCOME MEASURES

We report CO2 e per sampling approach, which is the unit used to express carbon footprint and harmonise the contributions of greenhouse gases with different global warming potentials.

RESULTS

The total carbon footprint of routine cervical sampling is 3670 g CO2 e. By comparison, vaginal self-sampling had a total carbon footprint of 423 g CO2 e, and FV urine sampling 570 g CO2 e. The largest share of emissions for routine sampling was attributable to the carbon footprint associated with an appointment in a primary care setting, which totalled 2768 g CO2 e.

CONCLUSIONS

Routine cervical sampling is up to 8.7-fold more carbon-intensive than self-sampling approaches with equivalent effectiveness. We found negligible differences in the carbon footprint of alternative self-sampling methods, supporting the need for an informed choice of screening options for participants, which includes sharing information on their environmental impacts.

Factors associated with cervical screening coverage: a longitudinal analysis of English general practices from 2013 to 2022

BACKGROUND

Cervical cancer remains an important global public health concern. Understanding the factors contributing to a decline in screening uptake in high-income countries is fundamental to improving screening rates. We aimed to identify general practice and patient characteristics related to cervical screening coverage in England between 2013 and 2022.

METHODS

We analyzed a panel of 59 271 General Practice (GP)-years from 7881 GP practices. We applied correlated random effects regression to examine the association between cervical screening uptake and a rich set of GP practice workforce, size, quality and patient characteristics.

RESULTS

Our results show a decline in overall screening rates from 2013/14 to 2021/22 from 77% to 72%. We find GP workforce and list size characteristics are strongly related to screening rates. An increase in 1 FTE Nurse per 1000 patients is related to a 1.94 percentage point increase in cervical screening rates. GP practices located in more deprived areas have lower screening rates.

CONCLUSIONS

GP workforce and patient characteristics need to be considered by decision-makers to increase screening rates. The implementation of self-sampling screening methods could help address some of the current barriers to screening, including lack of healthcare staff and facilities.

Cystic fibrosis to CFSPID: Burden of care vs need and rational approach to weaning therapies

We present a case of a 10-year-old boy initially diagnosed with CF based on NBS guidelines. However, as CF genetics knowledge has advanced, he has been reclassified as CFSPID based on normal investigations and excellent general clinical status, in line with updated CFSPID guidelines. This case highlights the significance of reviewing CF diagnoses according to the latest understanding of CFTR mutation phenotypes, as well as the patient's clinical status. In order to identify opportunities to save patients from burdensome CF treatment and management, we review current CFSPID guidelines, emphasizing care tailored to each individual case.

Limited value of serum neurofilament light chain in diagnosing amyotrophic lateral sclerosis

A biomarker specific for the diagnosis of amyotrophic lateral sclerosis must be sensitive across a spectrum of clinical heterogeneity. Neurofilament light chain levels in amyotrophic lateral sclerosis correlate with the rate of disability progression. Previous attempts to establish a diagnostic role for neurofilament light chain have been limited to comparison with healthy individuals or controls with alternative diagnoses unlikely to be confused with amyotrophic lateral sclerosis in real-world clinical practice. In a tertiary amyotrophic lateral sclerosis referral clinic, at first visit, serum was taken for neurofilament light chain measurement after prospectively recording the clinical diagnosis as 'amyotrophic lateral sclerosis', 'primary lateral sclerosis', 'alternative' or 'currently uncertain'. Of 133 referrals, 93 patients were diagnosed with amyotrophic lateral sclerosis (median neurofilament light chain 218.1 pg/ml, interquartile range 130.7-311.9), three primary lateral sclerosis (65.6, 51.5-106.9) and 19 alternative diagnoses (45.2, 13.5-71.9) at first visit. Of 18 initially uncertain diagnoses, eight were subsequently diagnosed with amyotrophic lateral sclerosis (98.5, 45.3-300.1). Neurofilament light chain ≥110.9 pg/ml had a positive predictive value of 0.92 for amyotrophic lateral sclerosis; <110.9 pg/ml had a negative predictive value of 0.48. In a specialized clinic, neurofilament light chain is largely confirmatory to clinical judgement in diagnosing amyotrophic lateral sclerosis and has limited ability to exclude alternative diagnoses. The current, important, value of neurofilament light chain is its potential to stratify patients with amyotrophic lateral sclerosis by disease activity and as a biomarker in therapeutic trials.

Molnupiravir plus usual care versus usual care alone as early treatment for adults with COVID-19 at increased risk of adverse outcomes (PANORAMIC): an open-label, platform-adaptive randomised controlled trial

BACKGROUND

The safety, effectiveness, and cost-effectiveness of molnupiravir, an oral antiviral medication for SARS-CoV-2, has not been established in vaccinated patients in the community at increased risk of morbidity and mortality from COVID-19. We aimed to establish whether the addition of molnupiravir to usual care reduced hospital admissions and deaths associated with COVID-19 in this population.

METHODS

PANORAMIC was a UK-based, national, multicentre, open-label, multigroup, prospective, platform adaptive randomised controlled trial. Eligible participants were aged 50 years or older-or aged 18 years or older with relevant comorbidities-and had been unwell with confirmed COVID-19 for 5 days or fewer in the community. Participants were randomly assigned (1:1) to receive 800 mg molnupiravir twice daily for 5 days plus usual care or usual care only. A secure, web-based system (Spinnaker) was used for randomisation, which was stratified by age (<50 years vs ≥50 years) and vaccination status (yes vs no). COVID-19 outcomes were tracked via a self-completed online daily diary for 28 days after randomisation. The primary outcome was all-cause hospitalisation or death within 28 days of randomisation, which was analysed using Bayesian models in all eligible participants who were randomly assigned. This trial is registered with ISRCTN, number 30448031.

FINDINGS

Between Dec 8, 2021, and April 27, 2022, 26 411 participants were randomly assigned, 12 821 to molnupiravir plus usual care, 12 962 to usual care alone, and 628 to other treatment groups (which will be reported separately). 12 529 participants from the molnupiravir plus usual care group, and 12 525 from the usual care group were included in the primary analysis population. The mean age of the population was 56·6 years (SD 12·6), and 24 290 (94%) of 25 708 participants had had at least three doses of a SARS-CoV-2 vaccine. Hospitalisations or deaths were recorded in 105 (1%) of 12 529 participants in the molnupiravir plus usual care group versus 98 (1%) of 12 525 in the usual care group (adjusted odds ratio 1·06 [95% Bayesian credible interval 0·81-1·41]; probability of superiority 0·33). There was no evidence of treatment interaction between subgroups. Serious adverse events were recorded for 50 (0·4%) of 12 774 participants in the molnupiravir plus usual care group and for 45 (0·3%) of 12 934 in the usual care group. None of these events were judged to be related to molnupiravir.

INTERPRETATION

Molnupiravir did not reduce the frequency of COVID-19-associated hospitalisations or death among high-risk vaccinated adults in the community.

FUNDING

UK National Institute for Health and Care Research.

Revisiting a diagnosis of cystic fibrosis - Uncertainties and considerations

There is now increased knowledge and experience of newborn screening around the world. There is also a better understanding of CF gene analysis, informed by international databases. This has resulted in a small number of children and adults having their diagnosis of CF reversed. This article illustrates this issue with three cases. It considers how best to tell children and adults with their families, and the reactions that may be encountered. It also discusses practical issues of removing the diagnosis.

Longitudinal analysis of urinary proteins in lupus nephritis - A pilot study

Approximately 30% of adult-onset systemic lupus erythematosus (SLE) patients develop lupus nephritis (LN). The gold standard for LN detection involves renal biopsies, invasive procedures not suitable for routine disease monitoring. A urinary biomarker panel comprised of lipocalin-like prostaglandin D synthase (LPGDS), transferrin, alpha-1-acid glycoprotein (AGP-1), ceruloplasmin, monocyte chemoattractant protein 1 (MCP-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) has shown promise to predict LN and response to rituximab at baseline. Whether these proteins predict LN during longitudinal sampling, however, remained unknown. Here, we quantified aforementioned urinary proteins at baseline (N = 25), six and twelve months (N = 17 each) after rituximab treatment. Urine MCP-1 (at six and twelve months) and AGP-1 (at twelve months) levels varied between patients with active vs mildly active/inactive LN. Findings support the use of urinary proteins to detect active LN in ongoing disease monitoring in adult-onset SLE patients, but need to be validated in larger cohorts.

A panel of urinary proteins predicts active lupus nephritis and response to rituximab treatment

OBJECTIVES

∼30% of patients with SLE develop LN. Presence and/or severity of LN are currently assessed by renal biopsy, but biomarkers in serum or urine samples may provide an avenue for non-invasive routine testing. We aimed to validate a urinary protein panel for its ability to predict active renal involvement in SLE.

METHODS

A total of 197 SLE patients and 48 healthy controls were recruited, and urine samples collected. Seventy-five of the SLE patients had active LN and 104 had no or inactive renal disease. Concentrations of lipocalin-like prostaglandin D synthase (LPGDS), transferrin, alpha-1-acid glycoprotein (AGP-1), ceruloplasmin, monocyte chemoattractant protein 1 (MCP-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) were quantified by MILLIPLEX® Assays using the MAGPIX Luminex platform. Binary logistic regression was conducted to examine whether proteins levels associate with active renal involvement and/or response to rituximab treatment.

RESULTS

Urine levels of transferrin (P <0.005), AGP-1 (P <0.0001), MCP-1 (P <0.001) and sVCAM-1 (P <0.005) were significantly higher in SLE patients when compared with healthy controls. Furthermore, levels of transferrin, AGP-1, ceruloplasmin, MCP-1 and sVCAM-1 (all P <0.0001) were higher in SLE patients with active LN when compared with patients without active LN. A combination of five urine proteins, namely LPGDS, transferrin, ceruloplasmin, MCP-1 and sVCAM-1 was a good predictor of active LN (AUC 0.898). A combined model of LPGDS, transferrin, AGP-1, ceruloplasmin, MCP-1 and sVCAM-1 predicted response to rituximab treatment at 12 months (AUC 0.818).

CONCLUSIONS

Findings support the use of a urinary protein panel to identify active LN and potentially predict response to treatment with rituximab in adult SLE patients. Prospective studies are required to confirm findings.

Guiding the rational design of patient-centred drug trials in Cystic Fibrosis: A Delphi study

BACKGROUND

Making trials more patient-centred improves recruitment and retention, patient satisfaction and makes research accessible to a more representative population. We aimed to understand the factors that influence participation and engagement in clinical trials in cystic fibrosis (CF) trials to guide the rational design and delivery of patient-centred trials.

METHODS

We used a Delphi process, supported by extensive literature review and 3 workshops, to determine which factors stakeholders think exert significant influence in participation and engagement in CF trials. Panellists were recruited from across the UK and the study was administered online.

RESULTS

We had representation from 19 CF centres; 28 people with CF (pwCF), 26 parents and 30 healthcare professionals (HCPs). Panels were presented with a shortlist of 104 factors and asked which they thought influence participation and engagement in CF trials. After 3 iterations, 43 statements met consensus for pwCF, 48 for the parents and 69 for the HCPs.

CONCLUSIONS

We identified many targets to make trials more patient-centred. Whilst some require an overhaul of trial delivery, many are relatively easy to implement. We outline a list of 'dos and don'ts' for sponsors and research teams including: focus on good communication; recognise that lack of time is the greatest barrier to trial participation so minimise the frequency and length of visits; help participants fit trials around busy lives; remember trial participation can be a major life-event and support participants accordingly; and don't underestimate the impact of simple strategies e.g. on-site access to Wifi and cups of tea.

Optimising equity of access: how should we allocate slots to the most competitive trials in Cystic Fibrosis (CF)?

BACKGROUND

Trial participation can allow people with CF early access to CFTR modulator therapies, with high potential for clinical benefit. Therefore, the number of people wishing to participate can substantially exceed the number of slots available. We aimed to understand how the CF community thinks slots to competitive trials should be allocated across the UK and whether this should be driven by clinical need, patients' engagement/adherence or be random. For the latter, we explored site-level versus registry-based, national randomisation processes.

METHODS

We developed an online survey, recruiting UK-based stakeholders through social media, newsletters and personal contacts. Closed questions were analysed for frequencies and percentages of responses. Free-text questions were analysed using thematic analysis.

RESULTS

We received 203 eligible responses. Overall, 75% of stakeholders favoured allocation of slots to individual sites based on patient population size, although pharma favoured allocation based on previous metrics. Currently, few centres have defined strategies for allocating slots locally. At face-value, stakeholders believe all eligible participants should have an equal chance of getting a slot. However, further questioning reveals preference for prioritisation strategies, primarily perceived treatment adherence, although healthcare professionals were less likely to favour this strategy than other stakeholder groups. The majority of stakeholders would prefer to allocate slots and participate in trials locally but 80% said if necessary, they would engage in a system of national allocation.

CONCLUSIONS

Fair allocation to highly competitive trials does not appear to have a universally acceptable solution. Therefore, transparency and empathy remain critical to negotiate this uncertain territory.

Urine and serum S100A8/A9 and S100A12 associate with active lupus nephritis and may predict response to rituximab treatment

BACKGROUND

Approximately 30% of patients with the systemic autoimmune/inflammatory disorder systemic lupus erythematosus (SLE) develop lupus nephritis (LN) that affects treatment and prognosis. Easily accessible biomarkers do not exist to reliably predict renal disease. The Maximizing SLE Therapeutic Potential by Application of Novel and Systemic Approaches and the Engineering Consortium aims to identify indicators of treatment responses in SLE. This study tested the applicability of calcium-binding S100 proteins in serum and urine as biomarkers for disease activity and response to treatment with rituximab (RTX) in LN.

METHODS

S100A8/A9 and S100A12 proteins were quantified in the serum and urine of 243 patients with SLE from the British Isles Lupus Assessment Group Biologics Register (BILAG-BR) study and 48 controls matched for age using Meso Scale Discovery's technology to determine whether they perform as biomarkers for active LN and/or may be used to predict response to treatment with RTX. Renal disease activity and response to treatment was based on BILAG-BR scores and changes in response to treatment.

RESULTS

Serum S100A12 (p<0.001), and serum and urine S100A8/A9 (p<0.001) levels are elevated in patients with SLE. While serum and urine S100 levels do not correlate with global disease activity (SLE Disease Activity Index), levels in urine and urine/serum ratios are elevated in patients with active LN. S100 proteins perform better as biomarkers for active LN involvement in patients with SLE who tested positive for anti-double-stranded DNA antibodies. Binary logistic regression and area under the curve analyses suggest the combination of serum S100A8/A9 and S100A12 can predict response to RTX treatment in LN after 6 months.

CONCLUSIONS

Findings from this study show promise for clinical application of S100 proteins to predict active renal disease in SLE and response to treatment with RTX.

Building global development strategies for cf therapeutics during a transitional cftr modulator era

As CFTR modulator therapy transforms the landscape of cystic fibrosis (CF) care, its lack of uniform access across the globe combined with the shift towards a new standard of care creates unique challenges for the development of future CF therapies. The advancement of a full and promising CF therapeutics pipeline remains a necessary priority to ensure maximal clinical benefits for all people with CF. It is through collaboration across the global CF community that we can optimize the evaluation and approval process of new therapies. To this end, we must identify areas for which harmonization is lacking and for which efficiencies can be gained to promote ethical, feasible, and credible study designs amidst the changing CF care landscape. This article summarizes the counsel from core advisors across multiple international regions and clinical trial networks, developed during a one-day workshop in October 2019. The goal of the workshop was to identify, in consideration of the highly transitional era of CFTR modulator availability, the drug development areas for which global alignment is currently uncertain, and paths forward that will enable advancement of CF therapeutic development.

Differential analysis of serum and urine S100 proteins in juvenile-onset systemic lupus erythematosus (jSLE)

Up to 80% of juvenile-onset systemic lupus erythematosus (jSLE) patients develop lupus nephritis (LN) that affects treatment and prognosis. Easily accessible biomarkers do not exist to reliably diagnose LN, leaving kidney biopsies as the gold-standard. Calcium-binding S100 proteins are expressed by innate immune cells and epithelia and may act as biomarkers in systemic inflammatory conditions. We quantified S100 proteins in the serum and urine of jSLE patients, matched healthy and inflammatory (IgA vasculitis) controls. Serum S100A8/A9, and serum and urine S100A12 are increased in jSLE patients when compared to controls. Furthermore, serum S100A8/A9, and serum and urine S100A12 are increased in jSLE patients with active as compared to patients with inactive/no LN. No differences in S100A4 levels were seen between groups. This study demonstrates potential promise for S100A8/A9 and S100A12 as biomarkers for jSLE and active LN. Findings require to be confirmed and tested prospectively in independent and larger multi-ethnic cohorts.

Potentiators and Correctors in Paediatric Cystic Fibrosis Patients: A Narrative Review

Cystic fibrosis is the most common inherited condition in the Caucasian population and is associated with significantly reduced life expectancy. Recent advances in treatment have focussed on addressing the underlying cause of the condition, the defective production, expression and function of the cystic fibrosis transmembrane conductance regulator (CFTR) protein. Several drugs with different modes of action have produced promising results in clinical trials, and some have been incorporated into routine clinical care for specific patients in many countries worldwide. Further trials continue to explore the safety and efficacy of these drugs in the youngest age groups and to search for more effective therapies to treat the most common disease-causing gene mutations in an ever-expanding drug pipeline. As evidence mounts for the early onset of disease in young patients, the prospect of introducing disease-modifying therapy in early life becomes more pertinent, although the cost implications of these expensive drugs are significant. In this review, we summarise these new therapy advances and review those currently being explored in clinical trials.

Variability of sweat chloride concentration in subjects with cystic fibrosis and G551D mutations

INTRODUCTION

Sweat chloride concentration, a biomarker of CFTR function, is an appropriate outcome parameter in clinical trials aimed at correcting the basic CF defect. Although there is consensus on a cut-off value to diagnose CF, we have only limited information on the within subject variability of sweat chloride over time. Such information would be useful for sample size calculations in clinical trials. Therefore, we retrospectively analyzed repeated sweat chloride values obtained in patients with G551D mutation(s) assigned to placebo in an ivacaftor interventional trial.

METHODS

In subjects with G551D at least 12years of age, a pilocarpine sweat test using Macroduct collector was taken on both arms at 8 time points over 48weeks. We explored 1062 pilocarpine sweat test values obtained in 78 placebo patients of the VX08-770-102 trial.

RESULTS

Mean overall sweat chloride value (all patients, all tests, n=1062) was 100.8mmol/L (SD 12.7mmol/L). Using a multilevel mixed model, the between-subject standard deviation (SD) for sweat chloride was 8.9mmol/L (95% CI 7.4-10.6) and within-subject SD was 8.1mmol/L (95% CI 7.5-8.7). Limits of repeatability for repeat measurements were -19.7 to +21.6mmol/L using values from one arm, and -13.3 to 11.8mmol/L using mean of values obtained at 4 test occasions. Sample size calculations showed that the minimal treatment effect on sweat chloride concentration that can be demonstrated for a group of 5 patients is around 15mmol/L, using a cross-over design and combinations of 4 tests for each phase of the trial.

CONCLUSION

Although the sweat test is considered a robust measure, sweat chloride measurements in patients with CF and a G551D mutation had an inherent biological variability that is higher than commonly considered. Further analyses of placebo group data are crucial to learn more about the natural variability of this outcome parameter.

Lung clearance index: evidence for use in clinical trials in cystic fibrosis

The ECFS-CTN Standardisation Committee has undertaken this review of lung clearance index as part of the group's work on evaluation of clinical endpoints with regard to their use in multicentre clinical trials in CF. The aims were 1) to review the literature on reliability, validity and responsiveness of LCI in patients with CF, 2) to gain consensus of the group on feasibility of LCI and 3) to gain consensus on answers to key questions regarding the promotion of LCI to surrogate endpoint status. It was concluded that LCI has an attractive feasibility and clinimetric properties profile and is particularly indicated for multicentre trials in young children with CF and patients with early or mild CF lung disease. This is the first article to collate the literature in this manner and support the use of LCI in clinical trials in CF.

The particle size dependence of the oxygen reduction reaction for carbon-supported platinum and palladium

Model carbon supported Pt and Pd electrocatalysts have been prepared using a high-throughput physical vapor deposition method. For Pt, metal particle sizes are controlled between 1.5-5.5 nm over 100 electrodes of an electrochemical screening chip, allowing the oxygen reduction reaction (ORR) activity of the catalysts to be determined simultaneously. The ORR-specific current density is observed to increase with increasing particle diameter up to approximately 4 nm, at which point the activity begins to level off. The reduction in ORR activity for particles below 4 nm is accompanied by a concomitant increase in the overpotential for surface reduction. The resulting mass activity exhibits a maximum for particles with diameters of approximately 3.5 nm. These results are consistent with results published recently for high area carbon-supported Pt catalysts. For Pd particles, both the specific current density and the mass-specific activity for the ORR are observed to increase with increasing particle diameter, with no distinct optimum observed. The implications for the optimization of Pt- or Pd-based ORR catalysts for proton exchange membrane fuel cell (PEMFC) applications are discussed.

Mannose-binding lectin is present in the infected airway: a possible pulmonary defence mechanism

BACKGROUND

Mannose-binding lectin (MBL) deficiency has been associated with infections of the respiratory tract and with increased disease severity in cystic fibrosis (CF). The mechanism is uncertain, and could relate either to systemic or local effects. The aim of this study was to determine, in a large cohort of children, whether MBL is present on the airway surface in health or disease.

METHODS

Bronchoalveolar lavage (BAL) fluid from children with and without respiratory infection (some with underlying disease) was analysed for MBL and neutrophil elastase (NE). Levels were compared between groups, and correlations were examined with local and systemic inflammatory markers, infective organisms and load.

RESULTS

85 children were recruited to the study. MBL was absent in the lavage of all 7 children without lung infection but present in 62% (8/13) of those with acute pneumonia/pneumonitis, 23% (5/22) with recurrent respiratory tract infections, 17% (1/6) with primary ciliary dyskinesia and 8% (3/37) with CF (p<0.01). Children with acute pneumonia/pneumonitis had significantly higher levels than those in the other groups. There was no relationship with organisms cultured or systemic markers of inflammation, although in the group with detectable MBL in the BAL fluid, the levels correlated positively with levels of NE.

CONCLUSIONS

MBL is undetectable in the non-infected airway but is present in a significant number of samples from children with lung infection. The levels found in the BAL fluid could be physiologically active and the protein may therefore be playing a role in host defence.

Pseudomonas aeruginosa, cyanide accumulation and lung function in CF and non-CF bronchiectasis patients

In patients with cystic fibrosis (CF) and non-CF bronchiectasis, Pseudomonas aeruginosa is the most important respiratory pathogen. It is able to synthesise hydrogen cyanide, a potent inhibitor of cellular respiration. The present study investigated whether cyanide is present in the sputum of CF and non-CF bronchiectasis patients infected with P. aeruginosa, and whether the detection of cyanide affected lung function. Cyanide was measured in sputum using a cyanide ion selective electrode. Cyanide was detected in sputum from 15 out of 25 CF and non-CF bronchiectasis patients with current P. aeruginosa infection; however, it was not detected in any of the 10 patients without this organism. Maximum levels were 130 microM (mean+/-SE 72+/-6.6 microM). Concurrent lung function data were available on all 21 P. aeruginosa-infected CF patients; the group with measurable sputum cyanide (n = 11) was not different from those without (n = 10) on the basis of age or sex. However, those with detectable cyanide had significantly poorer lung function than those without (forced expiratory volume in one second (% predicted) 26.8+/-3.8 versus 46.0+/-6.7%; forced vital capacity (% pred) 44.4+/-4.9 versus 60.1+/-7.7%). Cyanide is detectable in sputum from cystic fibrosis and non-cystic fibrosis bronchiectasis patients infected with Pseudomonas aeruginosa, and is also associated with impaired lung function.

Lung clearance index is a sensitive, repeatable and practical measure of airways disease in adults with cystic fibrosis

BACKGROUND

Lung clearance index (LCI) is a sensitive marker of early lung disease in children but has not been assessed in adults. Measurement is hindered by the complexity of the equipment required. The aims of this study were to assess performance of a novel gas analyser (Innocor) and to use it as a clinical tool for the measurement of LCI in cystic fibrosis (CF).

METHODS

LCI was measured in 48 healthy adults, 12 healthy school-age children and 33 adults with CF by performing an inert gas washout from 0.2% sulfur hexafluoride (SF6). SF6 signal:noise ratio and 10-90% rise time of Innocor were compared with a mass spectrometer used in similar studies in children.

RESULTS

Compared with the mass spectrometer, Innocor had a superior signal:noise ratio but a slower rise time (150 ms vs 60 ms) which may limit its use in very young children. Mean (SD) LCI in healthy adults was significantly different from that in patients with CF: 6.7 (0.4) vs 13.1 (3.8), p<0.001. Ten of the patients with CF had forced expiratory volume in 1 s > or = 80% predicted but only one had a normal LCI. LCI repeats were reproducible in all three groups of subjects (mean intra-visit coefficient of variation ranged from 3.6% to 5.4%).

CONCLUSIONS

Innocor can be adapted to measure LCI and affords a simpler alternative to a mass spectrometer. LCI is raised in adults with CF with normal spirometry, and may prove to be a more sensitive marker of the effects of treatment in this group.

Elimination of arctic variant rabies in red foxes, metropolitan Toronto

To control the arctic variant of rabies virus in red foxes, 332,257 bait doses containing live, attenuated Evelyn-Rokitnicki-Abelseth rabies vaccine were distributed in greater metropolitan Toronto during 1989–1999. Human and pet contact with bait was minimal, and no adverse reactions to the vaccine were noted. Significantly fewer rabid foxes were found during the 17 years after fox baiting (5 cases during 1990–2006) than in the 17 years before (96 cases during 1973–1989). The last report of a rabid fox in metropolitan Toronto was in 1996 (reporting period through September 2006), which confirms that distributing oral rabies vaccine bait is a feasible tactic for the control of rabies in foxes in urban environments.

Computed tomography and cystic fibrosis: promises and problems

Computed tomography (CT) has two potential roles in the evaluation of patients with cystic fibrosis (CF) lung disease: as a diagnostic test primarily for the detection of supervening complications and as a monitoring tool in clinical research. Interest in the latter role has gained momentum in the last 5 years because of two factors: (1) therapeutic options for CF lung disease are developing rapidly, hence the need for an outcome measure that can be applied in clinical intervention trials; and (2) it has become clear that traditional outcome measures such as pulmonary function tests are relatively insensitive to the early structural damage that occurs in CF. Several recent studies have shown that CT can be used as a potential surrogate outcome measure, although its suitability for this specific role is controversial and still under investigation. This review summarises current concepts relating to the research applications of CT in CF, with particular emphasis on the evidence supporting the use of CT as a surrogate outcome measure in clinical trials.

Safety of endobronchial biopsy in children with cystic fibrosis

There is little found in the published literature regarding the use of endobronchial biopsy (EBB) in children with cystic fibrosis (CF). One concern over the use of the technique may relate to safety, in particular increased risk of bleeding from a hypertrophied bronchial circulation. The aim of this retrospective study was to compare the safety of EBB in children with CF and those with other conditions, the most frequent of which included primary ciliary dyskinesia and recurrent lower respiratory tract infections. Case notes of all children undergoing EBB in our institution between February 2003 and May 2004 were reviewed. EBB was performed during 45 bronchoscopies in 42 CF patients (19 males, group mean age 7.13 +/- 4.48 years) and in 39 controls (20 males, group mean age 6.59 +/- 4.48 years). There were no significant differences between disease groups in the number, type, or severity of complications occurring during or in the first 12 hr after the procedure. We conclude that EBB performed as part of fibreoptic bronchoscopy (FOB) under general anaesthesia can be performed safely in children with CF, when both bronchoscopist and anaesthetist are suitably experienced. Studies of such samples would allow us to determine the early pathological changes in the CF airway and possibly find new treatments to prevent the progression to bronchiectasis and end stage airway destruction.

Novel antipseudomonal treatment approaches

Preventing and treating adequately Pseudomonas aeruginosa infection in the context of cystic fibrosis remains one of the most challenging topics of basic and clinical research in 2005. This state of the art review of antipseudomonal treatments describes some of the novel therapeutic approaches under development: active and passive immunisation, prevention of Pseudomonas aeruginosa adherence to cell surfaces, antibiofilm strategies, novel antimicrobial agents and inhaled dry powder antibiotics.

Tumour necrosis factor gene polymorphisms and childhood wheezing

Tumour necrosis factor (TNF)-alpha is associated with childhood wheezing. A genetic predisposition to increased TNF-alpha production, influenced by single nucleotide gene polymorphisms, may be important. Frequencies of TNF-alpha-308G/A and lymphotoxin (LT)-alpha+252G/A polymorphisms were compared in 115 asthmatic children, 55 wheezy infants and 156 control school children from the UK. Genotype frequencies for the TNF-alpha-308 and LT-alpha+252 polymorphisms were significantly different from controls. Haplotype analysis showed that TNF-alpha-308G, LT-alpha+252A/TNF-alpha-308A, LT-alpha+252A was associated with a markedly increased risk for both asthma and infant wheezing. The TNF-alpha-308G, LT-alpha+252G/TNF-alpha-308G, LT-alpha+252A combination was protective for asthma and infant wheezing. These findings were confirmed by analysis of Caucasian data. Nasal TNF-alpha levels were measured in the infants during acute wheezing episodes and higher, but nonsignificant levels were produced in those with one or two LT-alpha+252A alleles. Unexpectedly, significantly lower nasal TNF-alpha levels were found in the presence of one or two TNF-alpha-308A alleles. TNF-alpha-308/LT-alpha+252 genotype combinations had a significant influence on nasal TNF-alpha levels. In conclusion, these findings may have implications for future early intervention studies by helping to identify infants at increased risk for wheezing and childhood asthma.

Modifier genes in cystic fibrosis

Although over 1,000 disease-causing mutations in the CFTR gene have been described, the highly variable disease phenotype in cystic fibrosis (CF) cannot be explained on the basis of this gene alone. Both the environment and other non-CFTR genes are likely to be important. The increased understanding of pathophysiological processes in the CF lung has led to several studies on genes in these pathways, including those involved in host defense, mucin production, and airway responsiveness. Additionally, candidate modifiers of the gastrointestinal manifestations of CF have been explored. One of the major aims of such studies is to produce targets for novel drug developments. This review will summarize the field to date and discuss some of the methodological issues important in the design and interpretation of such studies.

Impaired pulmonary status in cystic fibrosis adults with two mutated MBL-2 alleles

Mannose-binding lectin has recently been identified as a modifier of severity in cystic fibrosis, although studies have produced differing results and the mechanism of action remains unclear. The current authors have studied large cohorts of adults (n=298) and children (n=260) to explore this apparent relationship further. Adults with two structural mutations, but not heterozygotes, had significantly reduced lung function and oxygen saturations, more frequent hospital admissions and raised systemic inflammatory markers. This was not related to increased rates of infection with Pseudomonas aeruginosa, and there was no increased susceptibility to Burkholderia cepacia. None of these findings was mirrored in the paediatric cohort. In conclusion, severe mannose-binding lectin deficiency appears to be detrimental to cystic fibrosis adults, although heterozygotes are not affected. It is suggested that this is not related to impaired complement-mediated bacterial killing, and a link with the host inflammatory response is hypothesised. If mannose-binding lectin replacement is developed as a new approach to treatment for this disease, the present study would suggest that the small group of severely deficient patients with two structural mutations may be the group to benefit.

Normal nasal mucociliary clearance in CF children: evidence against a CFTR-related defect

Studies on mucociliary clearance (MCC) in cystic fibrosis (CF) have produced conflicting results. This study aimed to differentiate primary (ion transport-related) from secondary (inflammatory) causes of delayed MCC in CF. Nasal MCC was measured in 50 children (CF, primary ciliary dyskinesia (PCD) and no respiratory disease). Nasal lavage fluid was analysed for interleukin (IL)-8 and tumour necrosis factor-alpha. Similar measurements were obtained in adult CF patients with and without chronic sinusitis (CS). Children with CF had neither delayed MCC nor increased levels of cytokines. Conversely, children with PCD had prolonged MCC times (all >30 min) and significantly raised levels of IL-8. CS-positive CF adults had significantly slower MCC than CS-negative subjects, but IL-8 levels were low and similar in both groups. Decreased airway surface liquid and delayed mucociliary clearance are the postulated primary mechanisms in cystic fibrosis. However, the current study reports that cystic fibrosis children have normal nasal mucociliary clearance. Abnormalities appeared in cystic fibrosis adults with symptoms of chronic sinus disease, suggesting a secondary rather than primary phenomenon. Studies to explore this mechanism in the distal, more sparsely-ciliated airways could aid an understanding of pathogenesis and the development of new treatments.

Multiresistant Pseudomonas aeruginosa in a pediatric cystic fibrosis center: natural history and implications for segregation

It has been suggested that cystic fibrosis (CF) patients harboring multiresistant (MR) Pseudomonas aeruginosa (PA) should be seen in separate clinics. The aim of this study was to test the feasibility of this by longitudinally studying the consistency of isolates of MRPA in individuals. We analyzed all respiratory tract cultures undertaken in 1 year from a pediatric CF clinic population (n = 367). PA was classified as MR according to the definition of the American CF Foundation: resistance to all agents in at least two of the following groups of antibiotics: beta-lactams, aminoglycosides, and fluroquinolones. PA was cultured from 96 children during the year of study. Thirty-six were infected with at least one MR strain. Following initial identification of MRPA, MR in subsequent cultures was highly variable. Twenty-three of 36 patients had subsequent cultures in which PA was identified. However, 21 of 23 patients had at least one isolate that was not MR following detection of MRPA. The variability with time in isolation of MR strains from individuals demonstrates the potential difficulties in designing segregation policies based on antibiotic sensitivity patterns.

A single round PCR method for genotyping human surfactant protein (SP)-A1, SP-A2 and SP-D gene alleles

The genes coding for the human surfactant proteins (SP)-A and SP-D are located on chromosome 10q22-q23.1. SP-D is the product of a single gene whereas SP-A is the product of two highly homologous genes SP-A1 and SP-A2. Several single nucleotide polymorphisms (SNP) are present in the SP-A1, SP-A2 and SP-D genes. Because of this high degree of sequence homology between the SP-A1 and SP-A2 genes, current genetic analysis studies employ a nested PCR/radioactive hybridization or restriction fragment length polymorphism approach to initially isolate the genes and subsequently to detect the SNP in these isolates. In this manuscript, we report the primers and conditions of a sequence specific primer-PCR methodology that enables the identification of SP-A1, SP-A2 and SP-D gene allelic variants directly on genomic DNA material.

Airway surface pH in subjects with cystic fibrosis

The cystic fibrosis (CF) transmembrane conductance regulator protein can transport bicarbonate and may therefore regulate airway surface (AS) pH. Disturbances of AS pH could contribute to the pathophysiology of CF lung disease. Five studies were carried out including the following: study 1) nasal pH measurements were made in 25 CF and 10 non-CF adults using an antimony pH probe. Mean nasal pH was significantly lower in the CF group. Nasal potential difference may have been a confounding factor; study 2) in a fresh cohort of CF and non-CF subjects, no significant difference was found between the two groups using a gold pH probe; study 3) simultaneous nasal pH measurements were made in 15 CF and 15 non-CF adults using both probes. In the CF group, there was a trend for the antimony probe to read lower than the gold probe. In the non-CF group, the antimony probe read higher. The pH difference noted in study 1 related to technical factors; study 4) the effect of acute changes in serum acid/base balance on nasal pH was assessed in five non-CF adults. Nasal pH was not altered by either acute respiratory acidosis or alkalosis; study 5) nasal and lower airway pH was measured in five CF and six non-CF children. No difference was found between the groups. There was a correlation between nasal and lower airway pH. The authors conclude that airway surface pH does not differ between cystic fibrosis and noncystic fibrosis subjects and therefore, cystic fibrosis transmembrane conductance regulator may not play a major role in airway surface pH in vivo.