Sorafenib for the treatment of advanced hepatocellular carcinoma

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of sorafenib according to its licensed indication for advanced hepatocellular carcinoma (HCC). The ERG report was based on the manufacturer's submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal process. The licensed indication for sorafenib specifies advanced HCC patients for whom locoregional intervention and surgery are unsuitable or had been unsuccessful. The clinical evidence came from a multicentre randomised controlled trial (Sorafenib HCC Assessment Randomized Protocol; SHARP) of sorafenib plus best supportive care versus placebo plus best supportive care, with 602 participants of a predominantly European ethnicity broadly comparable to the UK population. The submitted evidence indicated that for advanced HCC patients with Child-Pugh grade A liver function and relatively good Eastern Cooperative Oncology Group performance status, sorafenib on average improves overall survival by 83 days relative to placebo, and also increases time-to-radiological disease progression. Sorafenib therapy had little or no effect on time-to-symptom progression or on quality of life as measured using a disease-specific questionnaire. Sorafenib treatment was associated with increased incidence of hypertension and of gastrointestinal and dermatological problems. However, the therapy was reasonably well tolerated and, in SHARP, withdrawals from treatment due to adverse events were similar in the sorafenib and placebo arms, although more temporary reductions in dose were required in the sorafenib than in the placebo group. In the base case, the manufacturer's submitted economic analysis generated a deterministic incremental cost-effectiveness ratio (ICER) of 64,754 pounds per quality-adjusted life-year (QALY). The ERG extracted individual patient data for overall survival and disease progression, reran the economic model to check the submitted cost-effectiveness results, and performed new analyses which the ERG considered relevant to the decision problem; these analyses delivered ICERs between 76,000 pounds/QALY and 86,000 pounds/QALY. The guidance issued by NICE (7 May 2009) stated that sorafenib, within its licensed indication, is not recommended for the treatment of advanced (Barcelona-Clínic Liver Cancer stage C) HCC patients for whom surgical or locoregional therapies have failed or are not suitable, and people currently receiving sorafenib for the treatment of HCC should have the option to continue treatment until they and their clinician consider it appropriate to stop. Subsequently the manufacturer submitted a patient access scheme to the Department of Health. The base-case ICER submitted by the manufacturer for this scheme was 51,899 pounds/QALY. When the ERG reran the model with inputs considered relevant to the decision problem the ICER estimates ranged between 53,000 pounds to 58,000 pounds/QALY and substantially higher values depending on the nature of the sensitivity analyses. NICE considered the impact of the patient access scheme and determined that it was not sufficient to alter the guidance.

Imatinib as adjuvant treatment following resection of KIT-positive gastrointestinal stromal tumours

This is a summary of the evidence review group (ERG) report on the clinical effectiveness and cost-effectiveness of adjuvant imatinib post resection of KIT-positive gastrointestinal stromal tumours (GISTs) compared with resection only in patients at significant risk of relapse. The ERG report is based on the manufacturer’s submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal (STA) process. The bulk of the clinical evidence submitted was in the form of one randomised controlled trial (RCT), the Z9001 trial, funded by the manufacturer, which compared resection + adjuvant imatinib for 1 year to resection only. Results were immature, with median recurrence-free survival (RFS) not yet having been reached at the time of analysis. The trial did provide evidence of a delay in disease recurrence [1-year RFS rate of 98% in the imatinib arm vs 83% in the placebo arm [hazard ratio (HR) 0.35, 95% confidence interval (CI) 0.22 to 0.53, p < 0.0001)] but no evidence of an overall survival benefit. There was no long-term evidence around the rate of imatinib resistance over time with different treatment strategies (± adjuvant treatment). The relevant patient group for this appraisal is those at significant risk of relapse. These form a subgroup of the Z9001 trial, and all information regarding this group was designated ‘Commercial-in-Confidence’ (CIC). Median observation time for RFS was also CIC. The manufacturer constructed a Markov model comprising 10 health states designed to estimate costs and effects of treatment over a lifetime time horizon. The manufacturer’s estimate of the base-case incremental cost-effectiveness ratio (ICER) was £22,937/quality-adjusted life-year (subsequently amended by the manufacturer to £23,601). While the structure of the model reasonably reflected the natural history of the disease, the ERG had numerous concerns regarding the selection of, and assumptions around, input parameters (utilities, monthly probabilities of recurrence and death). Furthermore, the model was set up in such a way that any delay in recurrence translated directly into a survival benefit, an assumption that has no evidence base. A further assumption not supported by evidence was that any treatment benefit gained in the first year is carried on for a further 2 years at the same rate. Appropriate probabilistic sensitivity analysis was undertaken on the base case only, but not on scenario analyses, or choice of model used to estimate long-term survival data. The model was not amenable to changes in input values, thus limiting any additional analyses by the ERG to test assumptions. Due to the large number of uncertainties and assumptions, the estimated ICERs should be regarded as highly uncertain. The guidance issued by NICE in June 2010 as a result of the STA does not recommend imatinib as adjuvant treatment after resection of gastrointestinal stromal tumours, although individuals currently receiving adjuvant imatinib should have the option to continue treatment until they and their clinician consider it appropriate to stop.

Certolizumab pegol (CIMZIA®) for the treatment of rheumatoid arthritis

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of certolizumab pegol (CZP) for adults with active rheumatoid arthritis (RA) that have not responded adequately to treatment with conventional disease modifying anti-rheumatic drugs (DMARDs) including methotrexate (MTX), in accordance with the licensed indication, based upon the evidence submission from the manufacturer to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal (STA) process. The outcome measures included American College of Rheumatology (ACR) 20, 50 and 70 response rates and quality of life measures after 3 months and 6 months of treatment. The ERG examined the submission’s search strategies and considered they appeared comprehensive and that it was unlikely that relevant studies would have been missed. Only English language studies were considered in the submission and non-English language studies relevant to the decision problem may possibly have been ignored. The ERG analysed the first submitted economic model so as to itemise in detail clarification points that were brought to the attention of the manufacturer. In response the manufacturer submitted a modified cost-effectiveness analysis. The ERG undertook further analysis of this second model and other additional submitted evidence. The clinical evidence was derived from two multicentre blinded randomised controlled trials (RCTs) comparing CZP + MTX to placebo + MTX (the RAPID 1 and RAPID 2 trials). RAPID 1 lasted 52 weeks with 982 patients and RAPID 2 24 weeks with 619 patients. Evidence for clinical effectiveness of CZP in mono-therapy came from the 24-week FAST4WARD trial with 220 patients that compared CZP (400 mg every 4 weeks) versus placebo. The three key RCTs demonstrated statistically significant superiority of CZP + MTX versus placebo + MTX and of CZP versus placebo with respect to a variety of outcomes including ACR 20, ACR 50 and ACR 70 measures and quality of life measures at 3 and 6 months. On the basis of results from the indirect comparison meta-analyses, the manufacturer suggested that CZP may be at least as effective as other ‘biological’ DMARD (bDMARD) comparators and, in a few ACR measures at 3 and 6 months, more effective. CZP is an effective therapy for adult RA patients whose disease has failed to respond adequately to cDMARDs including MTX or who are intolerant of MTX. The cost-effectiveness of CZP relative to other bDMARDs is unclear because the economic modelling undertaken may have ignored relevant effectiveness data and potential differences between trial populations, and so may have included effectiveness results that were biased in favour of CZP; underestimated uncertainty in the relative effectiveness of compared DMARDs; and ignored the potential influence of differences between bDMARDs with regard to adverse events and their related costs and health impacts. The NICE guidance issued in October 2009 states that: the Committee is minded not to recommend certolizumab pegol as a treatment option for people with RA; and the Committee recommends that NICE asks the manufacturer of CZP for more information on the clinical effectiveness and cost-effectiveness of CZP for the treatment of people with RA. On receipt of this information and details of a patient access scheme NICE issued final guidance recommending CZP, under certain criteria, as a treatment option for people with RA.

Cetuximab for the first-line treatment of metastatic colorectal cancer

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of cetuximab for the first-line treatment of metastatic colorectal cancer (mCRC), in accordance with the licensed indication, based upon the manufacturer’s submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal process. The ERG project ran between 22 January 2008 and 4 November 2008. The clinical evidence came from two unpublished randomised controlled trials (RCTs) of cetuximab plus chemotherapy versus chemotherapy alone in the first-line treatment of mCRC. A third RCT submitted later compared cetuximab with irinotecan in combination with 5-fluorouracil (5-FU) and folinic acid (FA) and cetuximab with oxaliplatin in combination with 5-FU and FA in patients with mCRC with liver metastases only. No published economic evaluations of cetuximab for first-line chemotherapy in mCRC were identified in the submission. A de novo model examined the cost-effectiveness of cetuximab in patients with mCRC that was epidermal growth factor receptor positive, k-ras wild type and with liver metastases. The main source of clinical effectiveness evidence came from the first two RCTs which provided follow up information for 1–2 years. Secondary information was used to estimate survival for a further 22 years. The model focused on the patients for whom the treatment had been licensed. This limited the applicability of the model to the NHS setting in which patients would be a mixture of k-ras wild type and mutations and also a mixture of patients with liver metastases and other metastases. The difference in progress-free survival for the two trials was between 0.5 to 1.2 months over a 7–10 month period. Eight months’ treatment with cetuximab, given as an initial loading dose and then weekly until progression, would cost around £22,932 for an average man and £18,427 for an average woman. It is uncertain whether this constitutes good value for money. The guidance issued by NICE on 25 September 2008 stated that cetuximab was not recommended for the first-line treatment of mCRC and people currently receiving cetuximab for the first-line treatment of mCRC should have the option to continue treatment until they and their clinicians consider it appropriate to stop.

Sorafenib for the treatment of advanced hepatocellular carcinoma

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of sorafenib according to its licensed indication for advanced hepatocellular carcinoma (HCC). The ERG report was based on the manufacturer’s submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal process. The licensed indication for sorafenib specifies advanced HCC patients for whom locoregional intervention and surgery are unsuitable or had been unsuccessful. The clinical evidence came from a multicentre randomised controlled trial (Study of Heart and Renal Protection; SHARP) of sorafenib plus best supportive care versus placebo plus best supportive care, with 602 participants of a predominantly European ethnicity broadly comparable to the UK population. The submitted evidence indicated that for advanced HCC patients with Child–Pugh grade A liver function and relatively good Eastern Cooperative Oncology Group performance status, sorafenib on average improves overall survival by 83 days relative to placebo, and also increases time-to-radiological disease progression. Sorafenib therapy had little or no effect on time-to-symptom progression or on quality of life as measured using a disease-specific questionnaire. Sorafenib treatment was associated with increased incidence of hypertension and of gastrointestinal and dermatological problems. However, the therapy was reasonably well tolerated and, in SHARP, withdrawals from treatment due to adverse events were similar in the sorafenib and placebo arms, although more temporary reductions in dose were required in the sorafenib than in the placebo group. In the base case, the manufacturer’s submitted economic analysis generated a deterministic incremental cost-effectiveness ratio (ICER) of £64,754 per quality-adjusted life-year (QALY). The ERG extracted individual patient data for overall survival and disease progression, reran the economic model to check the submitted cost-effectiveness results, and performed new analyses which the ERG considered relevant to the decision problem; these analyses delivered ICERs between £76,000/QALY and £86,000/QALY. The guidance issued by NICE (7 May 2009) stated that sorafenib, within its licensed indication, is not recommended for the treatment of advanced (Barcelona-Clínic Liver Cancer stage C) HCC patients for whom surgical or locoregional therapies have failed or are not suitable, and people currently receiving sorafenib for the treatment of HCC should have the option to continue treatment until they and their clinician consider it appropriate to stop. Subsequently the manufacturer submitted a patient access scheme to the Department of Health. The base-case ICER submitted by the manufacturer for this scheme was £51,899/QALY. When the ERG reran the model with inputs considered relevant to the decision problem the ICER estimates ranged between £53,000 to £58,000/QALY and substantially higher values depending on the nature of the sensitivity analyses. NICE considered the impact of the patient access scheme and determined that it was not sufficient to alter the guidance.

Azacitidine for the treatment of myelodysplastic syndrome, chronic myelomonocytic leukaemia and acute myeloid leukaemia

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of azacitidine (aza) compared with conventional care regimes (CCR) for higher risk patients with myelodysplastic syndrome (MDS), chronic myelomonocytic leukaemia (CMML) and acute myeloid leukaemia (AML), based on the evidence submission from the manufacturer to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal process. The patient outcomes governing relative effectiveness and cost-effectiveness were defined as overall survival, time to progression (TTP) to AML, adverse events and health-related quality of life (HRQoL). The clinical evidence was derived from open label randomised controlled trial referred to as study AZA-001. It compared aza with CCR in 358 patients with higher risk MDS, CMML and AML 20–30% blasts. The outcomes reported in AZA-001 included overall survival, TTP to AML and adverse events. No HRQoL results were reported; however, outcomes likely to impact on HRQoL were provided. The results showed that: the median overall survival was 24.5 months on aza, compared with 15.0 months in the CCR group (p = 0.0001); the response rates were low (complete remission 17% aza versus 8% CCR); the median time to transformation to AML was greater in the aza group (17.8 versus 11.5 months; p < 0.0001); and of patients who were red blood cell (RBC) transfusion-dependent at baseline, 45% of those on aza became RBC transfusion-independent during the treatment period, compared with 11.8% in the CCR group (p < 0.0001). The ERG reran the submission’s search strategies after some modifications incorporating minor improvements. The ERG analysed the submitted economic model (model 1) and identified a number of inconsistencies and errors within the model. The manufacturer submitted a revised model for analysis by the ERG. Using the issues identified in the earlier analysis, the ERG conducted those repairs to the revised model that were feasible within time constraints. The ERG ran this version in probabilistic sensitivity analyses to generate cost-effectiveness acceptability frontiers. The results of these exploratory analyses indicated that: for standard-dose chemotherapy (SDC)-treated patients, of six treatment options available, best supportive care (BSC) was likely the most cost-effective option up to a threshold of £51,000/quality-adjusted life-year (QALY) [beyond £51,000/QALY, aza + low-dose chemotherapy (LDC) became cost-effective]; for LDC-treated patients, of four options available, BSC was again the most cost-effective option up to a willingness-to-pay threshold of £51,000/QALY (aza + LDC became cost-effective after £51,000/QALY); for BSC-treated patients, aza + BSC became cost-effective relative to BSC at a threshold of about £52,000/QALY. The ERG considers these results exploratory and considers that they should be viewed with caution. The AZA-001 study showed that, compared with CCR, those MDS patients receiving aza had prolonged median survival, had delayed progression to AML, had reduced dependence on transfusions and had a small improvement in response rate. Given the general paucity of economic modelling work in MDS and the limitations of the submitted industry model there is an evident need for an independent cost-effectiveness analysis of aza in MDS. At the time of writing, the guidance appraisal consultation document issued by NICE on 4 March 2010 states that azacitidine is not recommended as a treatment option for people not eligible for haemopoietic stem cell transplantation with the the following conditions: intermediate-2 and high-risk MDS according to the International Prognostic Scoring System, CMML with 10-29% marrow blasts without myeloproliferative disorder, or with AML with 20-30% blasts and multilineage dysplasia, according to World Health Organization classification.

Evaluating venepuncture practice on a general children's ward

AIM

To assess the training for, practice of, and effects of venepuncture in children on a general children's ward. To identify approaches that might reduce the adverse physical and psychological effects related to venepuncture.

METHODS

Questionnaire survey of 51 parents, 39 children and 72 junior doctors following venepuncture in the children. Telephone survey of 25 paediatric senior house officers on venous access training.

RESULTS

Parents and children assessed venepuncture as extremely distressing. Parents' assessments of the mean number of venepuncture attempts were markedly higher than those of the doctors surveyed. When carrying out venepuncture, doctors used therapeutic measures much less frequently than expected. Only seven of the 25 departments surveyed offered any training in venepuncture.

CONCLUSION

Venepuncture is consistently one of the most distressing aspects of hospital admission for children. Much could be done to alleviate this, but trainir patchy and interventions shown to reduce distress are not uniformly used.

Bacterial tracheitis: a multi-centre perspective

The published literature on bacterial tracheitis is limited. We report the first multi-centre study of bacterial tracheitis together with a concise review of the literature. We conducted a retrospective study of cases admitted during the period 1993-2007 to 3 tertiary paediatric centres in the United Kingdom and 1 in Australia. A total of 34 cases were identified. 31 patients (91%) required intubation. Complications included cardiorespiratory arrest in 1, ARDS in 1, hypotension in 10, toxic shock syndrome in 1 and renal failure in 1 patient(s). Staphylococcus aureus was the most commonly implicated bacterial organism, isolated from the respiratory tract in 55.8% of the cases overall. Other pathogens commonly isolated from the respiratory tract included Streptococcus pyogenes (5.9%), Streptococcus pneumoniae (11.8%) and Haemophilus influenzae (11.8%). Viral coinfection was identified in 9 (31%) of the 29 cases in whom immunofluorescence testing was performed (influenza A in 4 cases; parainfluenza 1 in 2 cases; parainfluenza 3 in 2 cases; adenovirus in 1 case). The combined experience from 4 major paediatric intensive care units suggests that bacterial tracheitis remains a rare condition with an estimated incidence of approximately 0.1/100,000 children per year. Short-term complications were common but long-term sequelae were rare. There were no fatal outcomes, which contrasts with the high historical mortality rates and likely reflects improvements in intensive care management.

Improving assessment with virtual patients

Assessments should accurately predict future performance in a wide variety of settings yet be feasible to conduct. In medical education a robust and comprehensive system of assessment is essential to protect the public from inadequate professionals. The parameters for devising such an assessment are well-defined, and good practice for writing examinations well-established. However even excellent written assessments are limited in their predictive validity, and limited in sampling, face and construct validity. The increasing availability and power of computing has led to growing interest in computer simulations for use in examinations, creating assessment virtual patients (AVPs). They can potentially test knowledge and data interpretation, incorporate images, sound or video and test decision making. Such AVPs could represent the most comprehensive, integrated assessment possible that is both objective and feasible. This article focuses on AVP design, distinguishing between linear and branched models, choice and consequence driven designs. It reviews the use of AVPs in the context of assessment theory. It presents different AVP designs discussing their benefits and problems. AVPs can become valuable components in high stakes medical exams, particularly in later years of courses. However this requires application of established assessment principles to AVP design.

The replacement of 'paper' cases by interactive online virtual patients in problem-based learning

St George's University of London (SGUL) has a Problem-Based Learning (PBL) curriculum for its undergraduate medicine course, using traditional paper-based patient cases. To counter the limitation that paper cases are linear and do not allow students to explore the consequences of decisions, interactive online virtual patients (VPs) were developed which allowed students to consider options as the cases unfold, and allow students to explore the consequences of their actions. A PBL module was converted to VPs, and delivered to 72 students in 10 tutorial groups, with 5 groups each week receiving VPs with options and consequences, and 5 groups receiving online VPs but without options. A comprehensive evaluation was carried out, using questionnaires, and interviews.Both tutors and students believed that the ability to explore options and consequences created a more engaging experience and encouraged students to explore their learning. They regretted the loss of paper and neither group could see any value in putting cases online without the options. SGUL is now adapting its transitional year between the early campus years and the clinical attachment years. This will include the integration of all technology-based resources with face-to-face learning and create a more adaptive, personalised, competency-based style of learning.

Early N-terminal pro-brain natriuretic peptide measurements predict clinically significant ductus arteriosus in preterm infants

We report a blinded, prospective study of the diagnostic utility of N-terminal pro-brain natriuretic peptide (NTproBNP) measurements for predicting clinically significant patent ductus arteriosus (PDA) and assessing closure.

METHODS

Plasma NTproBNP was measured during the first week in 100 preterm babies (mean gestation 28.8 +/- 2.9 weeks; mean birth weight 1224 +/- 512 g). Echocardiography was performed between days 5 and 7 by operators, blinded to NTproBNP concentration.

RESULTS

NTproBNP peaked on days 2 and 3, declined by day 7. Twenty babies, later treated for PDA, had significantly higher NTproBNP levels throughout. Areas under receiver operating characteristic (ROC) curves were 0.896, 0.897 and 0.931 on days 2, 3 and 7, respectively (p < 0.0001). A concentration > 2850 pmol/L had diagnostic sensitivity of 90% and specificity of 89% (95% CI: 68, 99; likelihood ratio 8.10). Ductal closure was associated with a fall in mean NTproBNP from 3003 to 839 pmol/L (p < 0.001).

CONCLUSION

N-terminal pro B-type brain natriuretic peptide (NTproBNP) concentrations peaked and then declined in the first week but remained higher in preterm babies whose PDA required treatment. NTproBNP on day 3 predicted whether a neonatal physician blinded to results would treat a PDA. Fall in plasma NTproBNP indicated closure.

Training staff to create simple interactive virtual patients: the impact on a medical and healthcare institution

BACKGROUND

Virtual patients (VPs) are excellent teaching tools for developing clinical decision-making skills and improving clinical competency, but are believed to be very expensive and time consuming to make.

AIM

The aim of this study was to establish whether it was possible to design a workshop for VP creation, which would enable teaching staff to create interactive, immersive VPs quickly, and with limited technical support.

METHODS

The Centre for Medical and Healthcare Education at St George's University of London's (SGUL) medical school developed an ergonomic and generic 'model' for VP creation, simple enough for clinicians and educators to use, yet flexible enough to simulate real decisions through non-linear pathways. One-day workshops were set up to support the development of VPs by medical and healthcare educators.

RESULTS

VP creation workshops have been successfully trialled, attracting a large number of clinicians and educators from a range of medicine and healthcare courses. Feedback from participants was very positive. Educators, organised into small groups, were unable to complete VPs within the workshop, but many groups completed a VP after the workshop. Interest was highest in mental health.

DISCUSSION

The workshops catalysed a change in the awareness of the value of VPs, with staff directly integrating VPs into the curriculum.

Choanal atresia: the result of maternal thyrotoxicosis or fetal carbimazole?

We present the fourth published case of a child affected with choanal atresia following maternal treatment with carbimazole. The mother was receiving her highest dose of carbimazole at the crucial period for development of the choanae, between days 35 and 38.

The natural history of developmental dysplasia of the hip after early supervised treatment in the Pavlik harness. A prospective, longitudinal follow-up

Between June 1988 and December 1997, we treated 332 babies with 546 dysplastic hips in a Pavlik harness for primary developmental dysplasia of the hip as detected by the selective screening programme in Southampton. Each was managed by a strict protocol including ultrasonic monitoring of treatment in the harness. The group was prospectively studied during a mean period of 6.5 +/- 2.7 years with follow-up of 89.9%. The acetabular index (AI) and centre-edge angle of Wiberg (CEA) were measured on annual radiographs to determine the development of the hip after treatment and were compared with published normal values. The harness failed to reduce 18 hips in 16 patients (15.2% of dislocations, 3.3% of DDH). These required surgical treatment. The development of those hips which were successfully treated in the harness showed no significant difference from the normal values of the AI for the left hips of girls after 18 months of age. Of those dysplastic hips which were successfully reduced in the harness, 2.4% showed persistent significant late dysplasia (CEA <20 degrees) and 0.2% persistent severe late dysplasia (CEA <15 degrees). All could be identified by an abnormal CEA (<20 degrees) at five years of age, and many from the progression of the AI by 18 months. Dysplasia was considered to be sufficient to require innominate osteotomy in five (0.9%). Avascular necrosis was noted in 1% of hips treated in the harness. We conclude that, using our protocol, successful initial treatment of DDH with the Pavlik harness appears to restore the natural development of the hip to normal. We suggest that regular radiological surveillance up to five years of age is a safe and effective practice.

The natural history of developmental dysplasia of the hip after early supervised treatment in the Pavlik harness

Between June 1988 and December 1997, we treated 332 babies with 546 dysplastic hips in a Pavlik harness for primary developmental dysplasia of the hip as detected by the selective screening programme in Southampton. Each was managed by a strict protocol including ultrasonic monitoring of treatment in the harness. The group was prospectively studied during a mean period of 6.5 ± 2.7 years with follow-up of 89.9%. The acetabular index (AI) and centre-edge angle of Wiberg (CEA) were measured on annual radiographs to determine the development of the hip after treatment and were compared with published normal values.

The harness failed to reduce 18 hips in 16 patients (15.2% of dislocations, 3.3% of DDH). These required surgical treatment. The development of those hips which were successfully treated in the harness showed no significant difference from the normal values of the AI for the left hips of girls after 18 months of age. Of those dysplastic hips which were successfully reduced in the harness, 2.4% showed persistent significant late dysplasia (CEA < 20°) and 0.2% persistent severe late dysplasia (CEA < 15°). All could be identified by an abnormal CEA (< 20°) at five years of age, and many from the progression of the AI by 18 months. Dysplasia was considered to be sufficient to require innominate osteotomy in five (0.9%). Avascular necrosis was noted in 1% of hips treated in the harness.

We conclude that, using our protocol, successful initial treatment of DDH with the Pavlik harness appears to restore the natural development of the hip to normal. We suggest that regular radiological surveillance up to five years of age is a safe and effective practice.

Isolation and characterization of the activated B-cell factor 1 homolog in Caenorhabditis elegans

Members of the basic helix-loop-helix (bHLH) family of transcription factors regulate a wide array of developmental processes in many cell types, including cell fate specification, differentiation and morphogenesis. Our studies describe the cloning of a gene from the nematode Caenorhabditis elegans that is closely related to the vertebrate-activated B-cell factor (ABF) gene. The nematode gene product CeABF-1 was detected by northern blot analysis from RNA isolated from pooled nematodes representing different developmental stages. The developmental expression profile of CeABF-1 was shown by RT-PCR analysis to be predominantly expressed in the larval stages L3 and L4, with lower levels observed in the L2 larval stage and adult. We also show that CeABF-1 is capable of forming heterodimers with E2A proteins and binding E-box target sites. Mammalian cells transfected with CeABF-1 expression plasmids were capable of blocking E2A-mediated gene transcription, but full repression activity required the presence of two conserved amino acid residues found within the first helix of the CeABF-1 bHLH domain. These results suggest a conserved mechanism of gene repression between certain class II bHLH and class I bHLH proteins found in vertebrates and invertebrates.

Characterization of a basic helix-loop-helix protein, ABF-1: nuclear localization, transcriptional properties, and interaction with Id-2

The activated B-cell factor (ABF)-1 cDNA was initially isolated from Epstein-Barr virus (EBV)-infected B cells and codes for a DNA-binding protein belonging to the basic helix-loop-helix (bHLH) family of transcription factors. In this study, we characterized the nuclear localization signal of ABF-1, mapped two distinct transcriptional repression domains, and identified one ABF-1-interacting protein, Id-2. By examining the subcellular location of deletion mutants of ABF-1 fused to green fluorescent protein (GFP), critical regions involved in nuclear localization were determined. Analysis of GFP-tagged ABF-1 deletion mutants revealed two separate regions capable of directing nuclear localization. One region mapped to the N-terminal amino acids 71 to 103, whereas the second region localized to the C-terminal bHLH domain. Transient transfection of ABF-1 deletion mutants demonstrated that the N-terminal amino acids 1 to 40 and the bHLH domain function together to achieve maximum repression of E2A activity. Taken together, these results indicate that ABF-1 is a nuclear transcriptional repressor with two distinct regions that function in a synergistic fashion to attenuate E2A-mediated gene activation.

A clinical evaluation of a direct radioimmunoassay of testosterone

We report the evaluation of a commercial coated tube kit (Medgenix) to the measurement of testosterone in plasma/serum samples. The accuracy, precision, specificity and recovery of the assay and the affinity of antibody for ligand were established. The range of concentrations of testosterone providing satisfactory analyses was 0.48-48 nmol/l, which is appropriate for general clinical use. Results of analysis of male and female samples obtained from the routine hospital laboratory in endocrinologically-defined groups were also reviewed. In all groups of male subjects and in normal females, the kit provided results in close agreement to those of an extraction method. With samples from women with various reproductive disorders, as well as with some samples obtained from external quality controls, the kit showed a small but significant negative bias relative to the results of the extraction method. There was, however, no evidence of bias with samples from a separate group of volunteer women with the polycystic ovary syndrome. No interference due to SHBG was detected. Clinical sensitivities using the kit were equivalent to those obtained using the extraction RIA. There was no evidence of spuriously high results in samples from females which has been a common problem with direct radioimmunoassay of testosterone.

Studies to confirm the source of 11 beta-hydroxyandrostenedione

In a longitudinal study of 82 children we found a gradual rise in median plasma concentrations of 11 beta-hydroxyandrostenedione (11 beta-OH-A4) from 2.5 to 6.4 nmol/l during childhood which was similar in both sexes. This could reflect changes in adrenal function during the adrenarche and sexual maturation. Plasma concentrations of 11 beta-OH-A4 in adults follow the patterns of cortisol secretion. In patients with diseases of the adrenal cortex, the plasma concentrations of 11 beta-OH-A4 were consistent with the pathology of each condition. In women with polycystic ovaries (PCO) undergoing gonadotrophic stimulation for in vitro fertilization and embryo transfer, 11 beta-OH-A4 (median = 3.8 nmol/l), testosterone and androstenedione, were raised when compared to women with normal ovaries (11 beta-OH-A4 median = 2.6 nmol/l). Follicular fluid has concentrations of 11 beta-OH-A4 six to twelve times greater than plasma levels and in women with PCO, 11 beta-OH-A4 concentrations were lower than in women with normal ovaries, which is consistent with an inhibition of ovarian 11 beta-hydroxylase. Granulosa cells in vitro demonstrated the production of 11 beta-OH-A4 by side chain cleavage of cortisol. These data support an adrenal source for 11 beta-OH-A4 but the raised plasma concentrations in women with polycystic ovary syndrome (PCOS) may reflect the excess androgen output from the ovary. 11 beta-OH-A4 may therefore be an additional marker for ovarian dysfunction.