The One-Stop Aortic Surveillance Clinic

Background

The principle of interval ultrasound surveillance of small abdominal aortic aneurysms (AAA) is well established. The fundamental principle of surveillance is that repair of AAA is a serious undertaking and the risk of the operation outweighs the risk of rupture in aneurysms less than 5.5 cm. Surveillance is well established but requires multiple visits to both the surgical clinic and the ultrasound department.

Report

This report presents a system whereby the vascular surgeon is trained in the process of aortic sonography with a view to one-stop clinic assessment. After training of the main investigators in aortic sonography, the surgeons performed scans on the aortas of 80 consecutive patients and compared the scan result with the subsequent formal scan.

Discussion

Surgical and radiographer scans correlate very closely. It is believed that the one-stop aortic surveillance model is safe, accurate, and improves both the patient journey and clinic throughput.

Biofouling control in a membrane filtration system by a newly isolated novel quorum quenching bacterium, Bacillus methylotrophicus sp. WY

A newly isolated QQ bacterium, Bacillus methylotrophicus strain WY substantially enhanced the membrane performance by reducing the rate of biofouling.

Spectacles in Stomach: A Case of Successful Endoscopic Removal

Ingestion of foreign bodies is a common reason for emergency visit. The ingested objects include batteries, needles, dentures, coins, sharps etc. Radiolucency and the length of the objects are important factors that affect their management. Long objects over 10 cm are less likely to pass through the duodenal curve. Sharp object that is not retrieved at the earliest may penetrate the wall and cause complications. We present here a challenging case of a middle aged psychiatric patient who swallowed long and sharp arms of her spectacles that were successfully retrieved endoscopically.

New digital technologies for the surveillance of infectious diseases at mass gathering events

Outbreaks of infectious diseases at mass gatherings can strain the health system of the host region and pose a threat to local and global health. In addition to strengthening existing surveillance systems, most host nations also use novel technologies to assess disease risk and augment traditional surveillance approaches. We review novel approaches to disease surveillance using the Internet, mobile phone applications, and wireless sensor networks. These novel approaches to disease surveillance can result in prompt detection.

Reliability of Carotid Doppler performed in a dedicated Stroke Prevention Clinic

Introduction:

Doppler ultrasound (DUS) is used as a screening tool to assess internal carotid artery (ICA) disease. Recent reports suggest that the DUS may be inaccurate in over 28% of patients. We sought to evaluate the accuracy of DUS, when performed in a dedicated stroke prevention clinic (SPC).

Methods:

We retrospectively reviewed the charts of patients who had a DUS performed in our SPC, followed by conventional cerebral angiography. Three groups of patients were defined. Group 1 had DUS measured ICA stenosis of >50%; Group II had a DUS measured ICA stenosis of <50%; Group III had complete ICA occlusion on DUS.

Results:

Sixty-seven patients (69 arteries) were included in the study. There were 45 patients in Group I and based on the findings of cerebral angiography, carotid endarterectomy was considered inappropriate in only one patient. - a misclassification rate of 2.2% (95%CI: 0 – 6.5%). Group II consisted of 19 patients and on cerebral angiography, none of these patients had a stenosis of >50% - a misclassification rate of 0%. Group III consisted of five patients in whom DUS showed complete ICA occlusion. The angiogram confirmed the occlusion in all five patients – a misclassification rate of 0%. Overall, misclassification rate was 1.45% (95% CI: 0 - 4.3%).

Conclusions:

Doppler ultrasound when performed in a stroke prevention clinic (SPC), has a high accuracy in measuring ICA stenosis of >50%. Doppler ultrasound is reliable in detecting complete ICA occlusion and finally DUS is a reliable screening tool to rule out clinically significant ICA stenosis.

A pilot study to assess oral health literacy by comparing a word recognition and comprehension tool

Background

Oral health literacy is important to oral health outcomes. Very little has been established on comparing word recognition to comprehension in oral health literacy especially in older adults. Our goal was to compare methods to measure oral health literacy in older adults by using the Rapid Estimate of Literacy in Dentistry (REALD-30) tool including word recognition and comprehension and by assessing comprehension of a brochure about dry mouth.

Methods

75 males and 75 females were recruited from the University of Connecticut Dental practice. Participants were English speakers and at least 50 years of age. They were asked to read the REALD-30 words out loud (word recognition) and then define them (comprehension). Each correctly-pronounced and defined word was scored 1 for total REALD-30 word recognition and REALD-30 comprehension scores of 0–30. Participants then read the National Institute of Dental and Craniofacial Research brochure “Dry Mouth” and answered three questions defining dry mouth, causes and treatment. Participants also completed a survey on dental behavior.

Results

Participants scored higher on REALD-30 word recognition with a mean of 22.98 (SD = 5.1) compared to REALD-30 comprehension with a mean of 16.1 (SD = 4.3). The mean score on the brochure comprehension was 5.1 of a possible total of 7 (SD = 1.6). Pearson correlations demonstrated significant associations among the three measures. Multivariate regression showed that females and those with higher education had significantly higher scores on REALD-30 word-recognition, and dry mouth brochure questions. Being white was significantly related to higher REALD-30 recognition and comprehension scores but not to the scores on the brochure.

Conclusions

This pilot study demonstrates the feasibility of using the REALD-30 and a brochure to assess literacy in a University setting among older adults. Participants had higher scores on the word recognition than on comprehension agreeing with other studies that recognition does not imply understanding.

Sentinel lymph node status in vulval cancer: systematic reviews of test accuracy and decision-analytic model-based economic evaluation

BACKGROUND

Vulval cancer causes 3-5% of all gynaecological malignancies and requires surgical removal and inguinofemoral lymphadenectomy (IFL). Complications affect > 50% of patients, including groin wound infection, lymphoedema and cellulitis. A sentinel lymph node (SLN) is the first groin node with the highest probability of malignancy. SLN biopsy would be useful if it could accurately identify patients in whom cancer has spread to the groin, without removing all groin nodes. SLNs can be identified by isosulfan blue dye and/or technetium-99 ((99m)Tc) radioactive tracer during lymphoscintigraphy. The blue dye/(99m)Tc procedure only detects SLN, not metastases - this requires histological examination, which can include ultrastaging and staining with conventional haematoxylin and eosin (H&E) or immunohistochemistry.

OBJECTIVES

To determine the test accuracy and cost-effectiveness of the SLN biopsy with (99m)Tc and/or blue dye compared with IFL or clinical follow-up for test negatives in vulval cancer, through systematic reviews and economic evaluation.

DATA SOURCES

Standard medical databases, including MEDLINE, EMBASE, Science Citation Index and The Cochrane Library, medical search gateways, reference lists of review articles and included studies were searched to January 2011.

METHODS

For accuracy and effectiveness, standard methods were used and reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Searches were to January 2011, with no language restrictions. Meta-analyses were carried out with Meta-Disc version 1.4 (Javier Zamora, Madrid, Spain) for accuracy; none was appropriate for effectiveness. The economic evaluation from a NHS perspective used a decision-tree model in DATA TreeAge Pro Healthcare 2001 (TreeAge Software, Inc., Williamstown, MA, USA). Six options (blue dye with H&E, blue dye with ultrastaging, (99m)Tc with H&E, (99m)Tc with ultrastaging, blue dye/(99m)Tc with H&E, blue dye/(99m)Tc with ultrastaging) were compared with IFL. Deterministic and probabilistic sensitivity analyses were conducted.

RESULTS

For accuracy, of the 26 included studies, most evaluated (99m)Tc/blue dye combined. Four studies had clinical follow-up only for test negatives and five had clinical follow-up for all and IFL for test negatives. Numbers with no SLN found were difficult to distinguish from those with negative SLN biopsies. The largest group of 11 studies using (99m)Tc/blue dye, ultrastaging and immunohistochemistry had a pooled sensitivity of 95.6% [95% confidence interval (CI) 91.5% to 98.1%] and a specificity of 100% (95% CI 99.0% to 100%). Mean SLN detection rates were 94.6% for (99m)Tc, 68.7% for blue dye and 97.7% for both. One study measured global health status quality of life (QoL) and found no difference between SLN biopsy and IFL. One patient preference evaluation showed that 66% preferred IFL rather than a 5% false-negative rate from SLN biopsy. For effectiveness, of 14,038 references, one randomised controlled trial, three case-control studies and 13 case series were found. Approximately 50% died from vulval cancer and 50% from other causes during follow-ups. Recurrences were in the ratio of approximately 4 : 2 : 1 vulval, groin and distant, with more recurrences in node-positive patients. No studies reported QoL. For cost per death averted, IFL was less costly and more effective than strategies using SLN biopsy. For morbidity-free survival and long-term morbidity-free survival, (99m)Tc with ultrastaging was most cost-effective. Strategies with blue dye only and H&E only were never cost-effective. The incremental cost-effectiveness ratio for (99m)Tc with ultrastaging compared with IFL was £4300 per case of morbidity-free survival and £7100 per long-term morbidity-free survival.

LIMITATIONS

The main limitations of this study include the lack of good-quality evidence on accuracy, effectiveness and QoL. A large project such as this takes time to publish, so the most recent studies are not included.

CONCLUSIONS

A sensitive and specific combined metastatic SLN detection test and information on generic QoL in vulval cancer is urgently required.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Sentinel lymph node biopsy in vulval cancer: systematic review and meta-analysis

BACKGROUND

The purpose of this study was to determine the accuracy of sentinel lymph node (SLN) biopsy with technetium 99 (99mTc) and/or blue dye-enhanced lymphoscintigraphy in vulval cancer.

METHODS

Sensitive searches of databases were performed upto October 2013. Studies with at least 75% of women with FIGO stage IB or II vulval cancer evaluating SLN biopsy with 99mTc, blue dye or both with reference standard of inguinofemoral lymphadenectomy (IFL) or clinical follow-up were included. Meta-analyses were performed using Meta-Disc version 1.4.

RESULTS

Of the 2950 references, 29 studies (1779 women) were included; most of them evaluated 99mTc combined with blue dye. Of these, 24 studies reported results for SLN followed by IFL, and 5 reported clinical follow-up only for SLN negatives. Pooling of all studies was inappropriate because of heterogeneity. Mean SLN detection rates were 94.0% for 99mTc, 68.7% for blue dye and 97.7% for both. SLN biopsy had pooled sensitivity of 95% (95% CI 92-98%) with negative predictive value (NPV) of 97.9% in studies using 99mTc/blue dye, ultrastaging and immunohistochemistry with IFL as reference. Pooled sensitivity for SLN with clinical follow-up for SLN-negatives was 91% (85-95%) with NPV 95.6%. Patients undergoing SLN biopsy experienced less morbidity than those undergoing IFL.

CONCLUSIONS

Sentinel lymph node biopsy using 99mTC, blue dye and ultrastaging with immunohistochemistry is highly accurate when restricted to carefully selected patients, within a rigorous protocol, with close follow-up and where sufficient numbers for learning curve optimisation exist. Patients must make an informed choice between the slightly higher groin recurrence rates of SLN biopsy vs the greater morbidity of IFL.

Rapid fetal fibronectin testing to predict preterm birth in women with symptoms of premature labour: a systematic review and cost analysis

BACKGROUND

Premature birth is defined as birth of before 37 completed weeks' gestation. Not all pregnant women showing symptoms of preterm labour will go on to deliver before 37 weeks' gestation. Hence, addition of fetal fibronectin (fFN) testing to the diagnostic workup of women with suspected preterm labour may help to identify those women who do not require active management, and thus avoid unnecessary interventions, hospitalisations and associated costs.

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of rapid fFN testing in predicting preterm birth (PTB) in symptomatic women.

DATA SOURCES

Bibliographic databases (including EMBASE, Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials) were searched from 2000 to September/November 2011. Trial registers were also searched.

REVIEW METHODS

Systematic review methods followed published guidance; we assessed clinical effectiveness and updated a previous systematic review of test accuracy. Risk of bias was assessed using the Cochrane tool (randomised controlled trials; RCTs) and a modification of QUADAS-2 (diagnostic test accuracy studies; DTAs). Summary risk ratios or weighted mean difference were calculated using random-effects models. Summary sensitivity and specificity used a bivariate summary receiver operating characteristic model. Heterogeneity was investigated using subgroup and sensitivity analyses. Health economic analysis focused on cost consequences. The time horizon was hospital admission for observation. A main structural assumption was that, compared with usual care, fFN testing doesn't increase adverse events or negative pregnancy outcomes.

RESULTS

Five RCTs and 15 new DTAs were identified. No RCT reported significant effects of fFN testing on maternal or neonatal outcomes. One study reported a subgroup analysis of women with negative fFN test observed > 6 hours, which showed a reduction in length of hospital stay where results were known to clinicians. Combining data from new studies and the previous systematic review, the pooled estimates of sensitivity and specificity were: 76.7% and 82.7% for delivery within 7-10 days of testing; 69.1% and 84.4% for delivery < 34 weeks' gestation; and 60.8% and 82.3% for delivery < 37 weeks' gestation. Estimates were similar across all subgroups sensitivity analyses. The base-case cost analysis resulted in a cost saving of £23.87 for fFN testing compared with usual care. The fFN testing was cost-neutral at an approximate cost of £45. Probabilistic sensitivity analysis gave an incremental cost (saving) of -£25.59 (97.5% confidence interval -£304.96 to £240.06), indicating substantial uncertainty. Sensitivity analyses indicated that admission rate had the largest impact on results.

CONCLUSIONS

Fetal fibronectin testing has moderate accuracy for predicting PTB. The main potential role is likely to be reducing health-care resource usage by identifying women not requiring intervention. Evidence from RCTs suggests that fFN does not increase adverse outcomes and may reduce resource use. The base-case analysis showed a modest cost difference in favour of fFN testing, which is largely dependent on whether or not fFN testing reduces hospital admission. Currently, there are no high-quality studies and the existing trials were generally underpowered. Hence, there is a need for high-quality adequately powered trials using appropriate study designs to confirm the findings presented.

STUDY REGISTRATION

PROSPERO 2011:CRD42011001468. Available from www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42011001468.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Birmingham and Lambeth Liver Evaluation Testing Strategies (BALLETS): a prospective cohort study

OBJECTIVE

To evaluate mildly abnormal liver function test (LFT) results in general practice among patients who do not have known liver disease.

DESIGN

Prospective cohort study of people with abnormal LFT results identified in primary care. Participants were intensively investigated using a common protocol and followed up for 2 years. Substudies investigated the psychological sequelae of abnormal test results, clinicians' reasons for testing, decision options when LFT results were abnormal and early detection of liver fibrosis.

SETTING

Eleven primary-care practices: eight in Birmingham and three in Lambeth.

PARTICIPANTS

Adults with abnormal LFT results who did not have pre-existing or obvious liver disease. Eight analytes were included in the panel of LFTs.

MAIN OUTCOME MEASURES

Statistical tests were used to identify the interactions between clinical features, the initial pattern of abnormal LFT results and (1) specific viral, genetic and autoimmune diseases, such as viral hepatitis, haemochromatosis and primary biliary cirrhosis; (2) a range of other serious diseases, such as metastatic cancer and hypothyroidism; (3) 'fatty liver' not associated with the above; and (4) the absence of detectable disease.

RESULTS

Fewer than 5% of people with abnormal LFT results had a specific disease of the liver, and many of these were unlikely to need treatment. The diagnostic potential of the LFT panel is largely subsumed into just two analytes: alanine aminotransferase (ALT) and alkaline phosphatase (ALP). Gamma-glutamyltransferase (GGT) offers a small increase in sensitivity at the margin at the cost of a large loss of specificity. Eighty-four per cent of abnormal LFT results remain abnormal on retesting 1 month later. In many cases, carrying out a definitive or specific test will be more efficient than repeating LFTs, with a view to specific testing only if the test remains abnormal. An ultrasound diagnosis of 'fatty liver' was present in nearly 40% of patients with abnormal LFTs and a small amount of weight loss over 2 years was associated with a reduced incidence of liver fat. There was a J-shaped relationship between alcohol intake and fatty liver in men. An abnormal LFT result causes temporary anxiety, which does not appear to promote sustained behaviour change.

CONCLUSIONS

Liver disease is rare among people with abnormal LFT results in primary care. Only two analytes (ALT and ALP) are helpful in identifying the majority of liver disease. GGT adds little information in return for a high false-positive rate but it is sensitive to alcohol intake. LFT results seldom revert from abnormal to normal over a 1-month period, and modelling shows that repeating an abnormal LFT panel, as recommended in the current guidelines, is inefficient. LFTs are often undertaken to meet perceived patient need for a blood test, but as they are neither specific nor indicative of any particular disease they are among the least suitable tests for this purpose. Obesity and raised ALT provide strong evidence for a presumptive diagnosis of 'fatty' liver. Abnormal LFTs and 'fatty' liver provoke only short-term anxiety and neither is associated with sustained weight loss. Even a small amount of weight loss reduces liver fat.

FUTURE WORK RECOMMENDATIONS

(1) the cases of 'fatty liver' and controls should be followed up in the long term to identify features that predict development of hepatosteatosis and then cirrhosis; (2) the acceptability of replacing the traditional six- to eight-analyte LFT panel with a drop down menu including the ALT/ALP combination should be evaluated.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

The 2012 dengue outbreak in Madeira: exploring the origins

In 2012, Madeira reported its first major outbreak of dengue. To identify the origin of the imported dengue virus, we investigated the interconnectivity via air travel between dengue-endemic countries and Madeira, and compared available sequences against GenBank. There were 22,948 air travellers to Madeira in 2012, originating from twenty-nine dengue-endemic countries; 89.6% of these international travellers originated from Venezuela and Brazil. We developed an importation index that takes into account both travel volume and the extent of dengue incidence in the country of origin. Venezuela and Brazil had by far the highest importation indices compared with all other dengue-endemic countries. The importation index for Venezuela was twice as high as that for Brazil. When taking into account seasonality in the months preceding the onset of the Madeira outbreak, this index was even seven times higher for Venezuela than for Brazil during this time. Dengue sequencing shows that the virus responsible for the Madeira outbreak was most closely related to viruses circulating in Venezuela, Brazil and Columbia. Applying the importation index, Venezuela was identified as the most likely origin of importation of dengue virus via travellers to Madeira. We propose that the importation index is a new additional tool that can help to identify and anticipate the most probable country of origin for importation of dengue into currently non-endemic countries.

Association between fetal position at onset of labor and mode of delivery: a prospective cohort study

OBJECTIVES

To determine the association between fetal position at onset of labor and mode of delivery, specifically left occipito-anterior (LOA) fetal position and spontaneous vaginal delivery (SVD).

METHODS

All nulliparous women who were booked at the Birmingham Women's NHS Foundation Trust over an 18-month period from April 2007 to September 2008 with a singleton live fetus without structural anomalies at term gestation were invited to take part in the study. Women recruited to the study underwent a transabdominal ultrasound scan to determine fetal occiput position at the onset of labor. They were then followed up until birth to determine outcome. The primary outcome measure was mode of delivery, categorized into SVD, instrumental delivery and Cesarean section.

RESULTS

Of 1647 eligible women, 1250 had valid scans at onset of labor; 155 of the 1250 (12.4%) had fetuses in the LOA position. Analysis showed no evidence of difference in odds ratio (OR) of SVD for fetuses in the LOA position compared with all other positions (OR 0.864 (95% CI, 0.617-1.209); P = 0.394). No difference remained with adjustment for confounding effects of variables known to influence mode of delivery (OR 0.837 (95% CI, 0.551-1.272); P = 0.405). No other occipital position showed significant association with SVD. There was no evidence of the LOA position being associated with Cesarean section, ventouse or forceps delivery.

CONCLUSION

There is no evidence of an association between the fetal LOA position at onset of labor and SVD. This finding challenges the conventional theory that LOA is the optimum fetal position at onset of labor, and suggests that antenatal practices encouraging adoption of the LOA position through maternal posturing are unnecessary.

Evaluating PET-CT in routine surveillance and follow-up after treatment for cervical cancer: a cost-effectiveness analysis

OBJECTIVE

To undertake a cost-effectiveness analysis that compares positron emission tomography - computed tomography (PET-CT) imaging plus standard practice with standard practice alone in the diagnosis of recurrent or persistent cervical cancer during routine surveillance and follow-up of women who have previously been diagnosed and treated.

DESIGN

Model-based economic evaluation using data from a systematic review, supplemented with data from other sources, and taking a UK National Health Service (NHS) perspective.

SETTING

Secondary Care in England.

POPULATION

Women at least 3 months after the completion of treatment, with either recurrent or persistent cervical cancer.

METHODS

A state transition (Markov) model was developed using TreeAge Pro 2011. The structure of the model was informed by the reviews of the trials and clinical input. In the model, two diagnostic strategies were examined. A one-way sensitivity analysis, probabilistic sensitivity analysis, and a value of information analysis were also carried out.

MAIN OUTCOME MEASURES

Cost-effectiveness based on incremental cost per quality-adjusted life year (QALY).

RESULTS

Adding PET-CT to the current treatment strategy of clinical examination and scanning [magnetic resonance imaging (MRI) and/or CT scan] during the routine surveillance and follow-up of women with recurrent or persistent cervical cancer is significantly more costly, with only a minimal increase in effectiveness. The incremental cost-effectiveness ratio (ICER) for the strategy of PET-CT as an adjunct to the standard treatment strategy that included clinical examination, MRI, and/or CT scan, compared with the usual treatment alone, was over £1 million per QALY.

CONCLUSION

The results of the current analysis suggest that use of PET-CT in the diagnosis of recurrent or persistent cervical cancer is not cost-effective. Current guidelines recommending imaging using PET-CT as a diagnostic or surveillance tool need to be reconsidered in light of these results. This study did not specifically investigate the use of PET-CT in women with symptoms and radiological suspicion of recurrence where exenteration was considered. More research in that specific area is required.

Evaluating PET-CT in the detection and management of recurrent cervical cancer: systematic reviews of diagnostic accuracy and subjective elicitation

BACKGROUND

Positron emission tomography-computed tomography (PET-CT) is recommended to triage women for exenterative surgery and surveillance after treatment for advanced cervical cancer.

OBJECTIVE

To evaluate diagnostic accuracy of additional whole body PET-CT compared with CT/magnetic resonance imaging (MRI) alone in women with suspected recurrent/persistent cervical cancer and in asymptomatic women as surveillance.

DESIGN

Systematic reviews. Subjective elicitation to supplement diagnostic information.

SEARCH STRATEGY/SELECTION CRITERIA/DATA COLLECTION AND ANALYSIS

Searches of electronic databases were performed to June 2013. Studies in women with suspected recurrent/persistent cervical cancer and in asymptomatic women undergoing follow up with sufficient numeric data were included. We calculated sensitivity, specificity and corresponding 95% confidence intervals. Meta-analyses employed a bivariate model that included a random-effects term for between-study variations (CT studies) and univariate random effects meta-analyses (PET-CT studies) for sensitivity and specificity separately.

SUBJECTIVE ELICITATION

Prevalence of recurrence and the accuracy of imaging elicited using the allocation of points technique. Coherence of elicited subjective probabilities with estimates in the literature examined.

RESULTS

We identified 15 relevant studies; none directly compared additional PET-CT with MRI or CT separately. Most CT and MRI studies used older protocols and the majority did not distinguish between asymptomatic and symptomatic women. Meta-analysis of nine PET-CT studies in mostly symptomatic women showed sensitivity of 94.8 (95% CI 91.2-96.9), and specificity of 86.9% (95% CI 82.2-90.5). The summary estimate of the sensitivity of CT for detection of recurrence was 89.64% (95% CI 81.59-94.41) and specificity was 76% (95% CI 43.68-92.82). Meta-analysis for MRI test accuracy studies was not possible because of clinical heterogeneity. The sensitivity and specificity of MRI in pelvic recurrence varied between 82 and 100% and between 78 and 100%, respectively. Formal statistical comparisons of the accuracy of index tests were not possible. Subjective elicitation provided estimates comparable to the literature. Subjective estimates of the increase in accuracy from the addition of PET-CT were less than elicited increases required to justify the use in PET-CT for surveillance.

CONCLUSION

Evidence to support additional PET-CT is scarce, of average quality and does not distinguish between application for surveillance and diagnosis. Guidelines recommending PET-CT in recurrent cervical cancer need to be reconsidered in the light of the existing evidence base.

Cost-effectiveness of sentinel lymph node biopsy vs inguinofemoral lymphadenectomy in women with vulval cancer

Background:

This study examines the cost-effectiveness of sentinel lymph node biopsy, a potentially less morbid procedure, compared with inguinofemoral lymphadenectomy (IFL) among women with stage I and stage II vulval squamous cell carcinoma.

Methods:

A model-based economic evaluation was undertaken based on clinical evidence from a systematic review of published sources. A decision tree model was developed with the structure being informed by clinical input, taking the perspective of the health-care provider.

Results:

For overall survival for 2 years, IFL was found to be the most cost-effective option and dominated all other strategies, being the least costly and most effective. For morbidity-free related outcomes for 2 years, sentinel lymph node (SLN) biopsy with 99mTc and blue dye and haematoxylin & eosin (H&E) histopathology, with ultrastaging and immunohistochemistry reserved for those that test negative following H&E is likely to be the most effective approach.

Conclusion:

SLN biopsy using 99mTc and blue dye with ultrastaging may be considered the most cost-effective strategy based on the outcome of survival free of morbidity for 2 years. The findings here also indicate that using blue dye and H&E for the identification of the SLN and the identification of metastasis, respectively, are not sensitive enough to be used on their own.

Positron emission tomography/computerised tomography imaging in detecting and managing recurrent cervical cancer: systematic review of evidence, elicitation of subjective probabilities and economic modelling

BACKGROUND

Cancer of the uterine cervix is a common cause of mortality in women. After initial treatment women may be symptom free, but the cancer may recur within a few years. It is uncertain whether it is more clinically effective to survey asymptomatic women for signs of recurrence or to await symptoms or signs before using imaging.

OBJECTIVES

This project compared the diagnostic accuracy of imaging using positron emission tomography/computerised tomography (PET-CT) with that of imaging using CT or magnetic resonance imaging (MRI) alone and evaluated the cost-effectiveness of adding PET-CT as an adjunct to standard practice.

DATA SOURCES

Standard systematic review methods were used to obtain and evaluate relevant test accuracy and effectiveness studies. Databases searched included MEDLINE, EMBASE, Science Citation Index and The Cochrane Library. All databases were searched from inception to May 2010.

REVIEW METHODS

Study quality was assessed using appropriately modified Quality Assessment of Diagnostic Accuracy Studies (QUADAS) criteria. Included were any studies of PET-CT, MRI or CT compared with the reference standard of histopathological findings or clinical follow-up in symptomatic women suspected of having recurrent or persistent cervical cancer and in asymptomatic women a minimum of 3 months after completion of primary treatment. Subjective elicitation of expert opinion was used to supplement diagnostic information needed for the economic evaluation. The effectiveness of treatment with chemotherapy, radiotherapy, chemoradiotherapy, radical hysterectomy and pelvic exenteration was systematically reviewed. Meta-analysis was carried out in RevMan 5.1 (The Cochrane Collaboration, The Nordic Cochrane Centre, Copenhagen, Denmark) and Stata version 11 (StataCorp LP, College Station, Texas, USA). A Markov model was developed to compare the relative cost-effectiveness using TreeAge Pro software version 2011 (TreeAge Software Inc., Evanston, IL, USA).

RESULTS

For the diagnostic review, a total of 7524 citations were identified, of which 12 test accuracy studies were included in the review: six studies evaluated PET-CT, two evaluated MRI, three evaluated CT and one evaluated both MRI and CT. All studies were small and the majority evaluated imaging in women in whom recurrence was suspected on the basis of symptoms. The PET-CT studies evaluated local and distant recurrence and most used methods similar to current practice, whereas five of the six CT and MRI studies evaluated local recurrence only and not all employed currently used methods. Meta-analysis of PET-CT studies gave a sensitivity of 92.2% [95% confidence interval (CI) 85.1% to 96.0%] and a specificity of 88.1% (95% CI 77.9% to 93.9%). MRI sensitivities and specificities varied between 82% and 100% and between 78% and 100%, respectively, and CT sensitivities and specificities varied between 78% and 93% and between 0% and 95%, respectively. One small study directly compared PET-CT with older imaging methods and showed more true-positives and fewer false-negatives with PET-CT. The subjective elicitation from 21 clinical experts gave test accuracy results for asymptomatic and symptomatic women and the results for symptomatic women were similar to those from the published literature. Their combined opinions also suggested that the mean elicited increase in accuracy from the addition of PET-CT to MRI and/or CT was less than the elicited minimum important difference in accuracy required to justify the routine addition of PET-CT for the investigation of women after completion of primary treatment. For the effectiveness review, a total of 24,943 citations were identified, of which 62 studies were included (chemotherapy, 19 randomised controlled trials; radiotherapy or chemoradiotherapy, 16 case series; radical hysterectomy and pelvic exenteration, 27 case series). None provided the effectiveness of cisplatin monotherapy, the most commonly used chemotherapeutic agent in the NHS, compared with supportive care in a background of other treatment such as radiotherapy in recurrent and persistent cervical cancer. The model results showed that adding PET-CT to the current treatment strategy of clinical examination, MRI and/or CT scan was significantly more costly with only a minimal increase in effectiveness, with incremental cost-effectiveness ratios for all models being > £1M per quality-adjusted life-year (QALY) and the additional cost per additional case of recurrence being in the region of £600,000.

LIMITATIONS

There was considerable uncertainty in many of the parameters used because of a lack of good-quality evidence in recurrent or persistent cervical cancer. The evidence on diagnostic and therapeutic impact incorporated in the economic model was poor and there was little information on surveillance of asymptomatic women.

CONCLUSIONS

Given the current evidence available, the addition of PET-CT to standard practice was not found to be cost-effective in the diagnosis of recurrent or persistent cervical cancer. However, although probabilistic sensitivity analysis showed that the main conclusion about cost-ineffectiveness of PET-CT was firm given the range of assumptions made, should more reliable information become available on accuracy, therapeutic impact and effectiveness, and the cost of PET-CT reduce, this conclusion may need revision. Current guidelines recommending imaging for diagnosis using expensive methods such as PET-CT need to be reconsidered in the light of the above.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Targeting the endothelin axis in scleroderma renal crisis: rationale and feasibility

BACKGROUND

We have studied endothelin-1 (ET-1) levels and ET-1 ligand and receptor tissue expression in scleroderma renal crisis (SRC) and undertaken a pilot open label safety study of bosentan, a non-selective ET-1 receptor antagonist, in SRC [Bosentan in Renal Disease-1 (BIRD-1)].

METHODS

Serum levels of ET-1 were measured in healthy controls (n = 20) or systemic sclerosis (SSc) (n = 80) with or without SRC, including cases of pulmonary arterial hypertension (PAH). Renal biopsies (n = 27) from patients with SRC were stained for endothelin ligand and receptors. Six cases of SRC received 6 months bosentan. Outcome measures were compared with SRC cases managed at our centre from 2000 to 2004 (n = 49).

RESULTS

Serum ET-1 was elevated in SRC but less than in PAH. ET-1 and both endothelin A and endothelin B receptor expression was increased in SRC biopsies in glomeruli, interstitium and hallmark vascular lesions of SRC. In the BIRD-1 cohort, serum ET-1 was elevated in all cases at SRC (median healthy controls 0.50 pg/ml; SRC 1.48 pg/ml; P < 0.0005), and increased further with bosentan therapy (1.46 vs. 3.05 pg/ml; t-test P < 0.05). Bosentan was well tolerated with no significant drug-related serious adverse events and long-term outcomes were favourable compared with historic cases. Three patients developed rebound hypertension on withdrawal of bosentan and one appeared to further benefit from maintenance therapy.

CONCLUSION

Upregulation of ET-1 ligand axis suggests that ET-1 receptor blockade is logical and treatment with bosentan appears to be safe in SRC. Future studies to assess therapeutic benefit and compare selective or non-selective receptor antagonists are justified.

Has the incidence of urolithiasis presenting to secondary care increased in the last 10 years?

Objective:

Urolithiasis presenting to secondary care has been proposed to be on the increase, in the United Kingdom, based on national Hospital Episode Statistics data. We aimed to assess whether there has been an increase in stone disease presenting to a district general hospital in the last 10 years.

Methods:

A prospective stone database has been kept for all patients attending the urology department of a district general hospital from 2002. We assessed five yearly intervals to identify changes in incidence, gender and age distribution, and stone composition rates.

Results:

A 26% increase in calculi presenting to the urology department was noted in the last 10 years. This was in relation to a 2% population increase. This also resulted in a 26% increase in operations for urinary calculi. The increases were equal for men and women, and the mean age of presentation remained the same. There were no significant differences in the findings of stone composition in the last 10 years or in the surgical method of stone extraction.

Conclusion:

Urolithiasis presenting to the urologist is on the increase, leading to a greater need for urological procedures. Stone services may need to be increased to deal with this increasing demand.

Isoformononetin, a methoxydaidzein present in medicinal plants, reverses bone loss in osteopenic rats and exerts bone anabolic action by preventing osteoblast apoptosis

PURPOSE

Daidzein (Daid) has been implicated in bone health for its estrogen-'like' effects but low bioavailability, unfavorable metabolism and uterine estrogenicity impede its clinical potential. This study was aimed at assessing isoformononetin (Isoformo), a naturally occurring methoxydaidzein, for bone anabolic effect by overcoming the pitfalls associated with Daid.

METHODS

Sprague-Dawley ovariectomized (OVx) rats with established osteopenia were administered Isoformo, 17β-oestradiol (E2) or human parathyroid hormone. Efficacy was evaluated by bone microarchitecture using microcomputed tomography and determination of new bone formation by fluorescent labeling of bone. Osteoblast apoptosis was measured by co-labeling of bone sections with Runx-2 and TUNEL. Biochemical markers of bone metabolism were measured by ELISA. Plasma and bone marrow levels of Isoformo and Daid were determined by LC-MS-MS. Rat bone marrow stromal cells were harvested to study osteoblastic differentiation by Isoformo and Daid. New born rat pups were injected with Isoformo and Daid to study the effect of the compounds on the expression of osteogenic genes in the calvaria by real time PCR.

RESULTS

In osteopenic rats, Isoformo treatment restored trabecular microarchitecture, increased new bone formation, increased the serum osteogenic marker (procollagen N-terminal propeptide), decreased resorptive marker (urinary C-terminal teleopeptide of type I collagen) and diminished osteoblast apoptosis in bone. At the most effective osteogenic dose of Isoformo, plasma and bone marrow levels were comprised of ~90% Isoformo and the rest, Daid. Isoformo at the concentration reaching the bone marrow achieved out of its most effective oral dosing induced stromal cell mineralization and osteogenic gene expression in the calvaria of neonatal rats. Isoformo exhibited uterine safety.

CONCLUSIONS

Our study demonstrates that Isoformo reverses established osteopenia in adult OVx rats likely via its pro-survival effect on osteoblasts. Given its bone anabolic and anti-catabolic effects accompanied with safety at uterine level we propose its potential in the management of postmenopausal osteoporosis.

Positive skeletal effects of cladrin, a naturally occurring dimethoxydaidzein, in osteopenic rats that were maintained after treatment discontinuation

Effects of cladrin treatment and withdrawal in osteopenic rats were studied. Cladrin improved trabecular microarchitecture, increased lumbar vertebral compressive strength, augmented coupled remodeling, and increased bone osteogenic genes. A significant skeletal gain was maintained 4 weeks after cladrin withdrawal. Findings suggest that cladrin has significant positive skeletal effects.

INTRODUCTION

We showed that a standardized extract of Butea monosperma preserved trabecular bone mass in ovariectomized (OVx) rats. Cladrin, the most abundant bioactive compound of the extract, promoted peak bone mass achievement in growing rats by stimulating osteoblast function. Here, we studied the effects of cladrin treatment and withdrawal on the osteopenic bones.

METHODS

Adult female Sprague-Dawley rats were OVx and left untreated for 12 weeks to allow for significant estrogen deficiency-induced bone loss, at which point cladrin (1 and 10 mg/kg/day) was administered orally for another 12 weeks. Half of the rats were killed at the end of the treatments and the other half at 4 weeks after treatment withdrawal. Sham-operated rats and OVx rats treated with PTH or 17β-estradiol (E2) served as various controls. Efficacy was evaluated by bone microarchitecture using microcomputed tomographic analysis and fluorescent labeling of bone. qPCR and western blotting measured mRNA and protein levels in bone and uterus. Specific ELISA was used for measuring levels of serum PINP and urinary CTx.

RESULTS

In osteopenic rats, cladrin treatment dose dependently improved trabecular microarchitecture, increased lumbar vertebral compression strength, bone formation rate (BFR), cortical thickness (Cs.Th), serum PINP levels, and expression of osteogenic genes in bones; and reduced expression of bone osteoclastogenic genes and urinary CTx levels. Cladrin had no uterine estrogenicity. Cladrin at 10 mg/kg maintained acquired skeletal gains 4 weeks after withdrawal.

CONCLUSION

Cladrin had positive skeletal effects in osteopenic rats that were maintained after treatment withdrawal.

Comparing diagnostic tests: trials in people with discordant test results

Diagnostic tests are traditionally compared for accuracy against a gold standard but can also be compared prospectively in a trial. A conventional trial comparing two tests would randomize each participant to a testing strategy, but a more efficient alternative is to give both tests to all participants and follow up those with discordant results. Participants could be randomized before or after testing. The statistical analysis of such a trial has not previously been described. We investigated two estimates of the risk difference for a binary outcome: one based on analysing outcomes as if from a conventional trial and one combining estimates of different parameters in the manner of a decision analysis. We show that the trial estimate and decision analysis estimate are both unbiased and derive approximate formulae for their standard errors. By using the decision analysis estimate (but not the trial estimate), the same precision can be achieved by randomizing before testing as by randomizing after. To avoid destroying equipoise, and to allow consenting and randomizing to be carried out at the same visit, we recommend randomizing before testing. Giving both tests to all participants means fewer need to be recruited: in one example from the literature, the proposed design was nearly four times more efficient in this sense than a conventional trial design.

Vitamin K supplementation for the primary prevention of osteoporotic fractures: is it cost-effective and is future research warranted?

Lifetime supplementation with vitamin K, vitamin D(3), and calcium is likely to reduce fractures and increase survival in postmenopausal women. It would be a cost-effective intervention at commonly used thresholds, but high uncertainty around the cost-effectiveness estimates persists. Further research on the effect of vitamin K on fractures is warranted.

INTRODUCTION

Vitamin K might have a role in the primary prevention of fractures, but uncertainties about its effectiveness and cost-effectiveness persist.

METHODS

We developed a state-transition probabilistic microsimulation model to quantify the cost-effectiveness of various interventions to prevent fractures in 50-year-old postmenopausal women without osteoporosis. We compared no supplementation, vitamin D(3) (800 IU/day) with calcium (1,200 mg/day), and vitamin K(2) (45 mg/day) with vitamin D(3) and calcium (at the same doses). An additional analysis explored replacing vitamin K(2) with vitamin K(1) (5 mg/day).

RESULTS

Adding vitamin K(2) to vitamin D(3) with calcium reduced the lifetime probability of at least one fracture by 25%, increased discounted survival by 0.7 quality-adjusted life-years (QALYs) (95% credible interval (CrI) 0.2; 1.3) and discounted costs by $8,956, yielding an incremental cost-effectiveness ratio (ICER) of $12,268/QALY. At a $50,000/QALY threshold, the probability of cost-effectiveness was 95% and the population expected value of perfect information (EVPI) was $28.9 billion. Adding vitamin K(1) to vitamin D and calcium reduced the lifetime probability of at least one fracture by 20%, increased discounted survival by 0.4 QALYs (95% CrI -1.9; 1.4) and discounted costs by $4,014, yielding an ICER of $9,557/QALY. At a $50,000/QALY threshold, the probability of cost-effectiveness was 80% while the EVPI was $414.9 billion. The efficacy of vitamin K was the most important parameter in sensitivity analyses.

CONCLUSIONS

Lifetime supplementation with vitamin K, vitamin D(3), and calcium is likely to reduce fractures and increase survival in postmenopausal women. Given high uncertainty around the cost-effectiveness estimates, further research on the efficacy of vitamin K on fractures is warranted.

Malaria burden in human population of Quetta, Pakistan

Malaria is a serious global health challenge, which is responsible for more than one million deaths a year. Malarial infection is more prevalent in developing countries including Pakistan. Significant efforts have been made to control malaria; however, due to socio-environmental factors, it remains a frequent problem in Quetta. The present study was undertaken to determine the malarial incidence, species prevalence, and its demographic evaluation in human population of Quetta, Pakistan. A total of 1831 subjects, comprising 1072 male and 759 female presenting symptoms of malaria, were included in this study. Blood samples from clinically suspected individuals were subjected to the standard immunochromatographic and malaria parasite smear analysis for malaria diagnosis. Out of 1831 subjects, 338 (18.45%) patients were positive for malarial parasite while the species prevalence was found as 276 (81.66%) and 62 (18.34%) for Plasmodium vivax, and Plasmodium falciparum, respectively. Furthermore, seasonal variations gradual increase in the prevalence rate. The age group of 21-30 years (30.47%) was found more prone to malaria. The suspected malaria cases were found more frequent in rural (72.1%) as compared to urban (27.9%). In addition, the malaria burden was high in urban area (22.89%) population as compared to the rural area (16.74%) population. It was observed that the highest disease occurrence was caused by P. vivax, which reflects a serious threat for public health. The current findings will be helpful to plan effective strategies to prevent and control malaria in this area.

Are all patients diagnosed with tuberculosis in Indian medical colleges referred to the RNTCP?

To assess the proportion of tuberculosis (TB) patients diagnosed in three medical colleges in the states of West Bengal and Meghalaya who benefited from the services provided under the Revised National Tuberculosis Control Programme (RNTCP), a line list of patients with reports of investigations suggesting probable or confirmed TB was prepared from the records of the pathology, radiology and microbiology departments. This was compared with another line list prepared using RNTCP records. Only 150 (36%) of 420 probable or confirmed TB patients were referred to the RNTCP services. This suggests a need for more intensive supervision and training of medical college faculty.