Multicenter evaluation of the BIOFIRE Joint Infection Panel for the detection of bacteria, yeast, and AMR genes in synovial fluid samples

The bioMérieux BIOFIRE Joint Infection (JI) Panel is a multiplex in vitro diagnostic test for the simultaneous and rapid (~1 h) detection of 39 potential pathogens and antimicrobial resistance (AMR) genes directly from synovial fluid (SF) samples. Thirty-one species or groups of microorganisms are included in the kit, as well as several AMR genes. This study, performed to evaluate the BIOFIRE JI Panel for regulatory clearance, provides data from a multicenter evaluation of 1,544 prospectively collected residual SF samples with performance compared to standard-of-care (SOC) culture for organisms or polymerase chain reaction (PCR) and sequencing for AMR genes. The BIOFIRE JI Panel demonstrated a sensitivity of 90.9% or greater for all but six organisms and a positive percent agreement (PPA) of 100% for all AMR genes. The BIOFIRE JI Panel demonstrated a specificity of 98.5% or greater for detection of all organisms and a negative percent agreement (NPA) of 95.7% or greater for all AMR genes. The BIOFIRE JI Panel provides an improvement over SOC culture, with a substantially shorter time to result for both organisms and AMR genes with excellent sensitivity/PPA and specificity/NPA, and is anticipated to provide timely and actionable diagnostic information for joint infections in a variety of clinical scenarios.

Multicenter Evaluation of the BIOFIRE Blood Culture Identification 2 Panel for Detection of Bacteria, Yeasts, and Antimicrobial Resistance Genes in Positive Blood Culture Samples

Diagnostic tools that can rapidly identify and characterize microbes growing in blood cultures are important components of clinical microbiology practice because they help to provide timely information that can be used to optimize patient management. This publication describes the bioMérieux BIOFIRE Blood Culture Identification 2 (BCID2) Panel clinical study that was submitted to the U.S. Food & Drug Administration. Results obtained with the BIOFIRE BCID2 Panel were compared to standard-of-care (SoC) results, sequencing results, PCR results, and reference laboratory antimicrobial susceptibility testing results to evaluate the accuracy of its performance. Results for 1,093 retrospectively and prospectively collected positive blood culture samples were initially enrolled, and 1,074 samples met the study criteria and were included in the final analyses. The BIOFIRE BCID2 Panel demonstrated an overall sensitivity of 98.9% (1,712/1,731) and an overall specificity of 99.6% (33,592/33,711) for Gram-positive bacteria, Gram-negative bacteria and yeast targets which the panel is designed to detect. One hundred eighteen off-panel organisms, which the BIOFIRE BCID2 Panel is not designed to detect, were identified by SoC in 10.6% (114/1,074) of samples. The BIOFIRE BCID2 Panel also demonstrated an overall positive percent agreement (PPA) of 97.9% (325/332) and an overall negative percent agreement (NPA) of 99.9% (2,465/2,767) for antimicrobial resistance determinants which the panel is designed to detect. The presence or absence of resistance markers in Enterobacterales correlated closely with phenotypic susceptibility and resistance. We conclude that the BIOFIRE BCID2 Panel produced accurate results in this clinical trial.

Adverse events and overall health and well-being after COVID-19 vaccination: interim results from the VAC4COVID cohort safety study

OBJECTIVES

To describe the incidence of adverse events (AEs), reactogenicity symptoms, menstrual changes and overall self-rated improvement in health and well-being after COVID-19 vaccination.

DESIGN

VAC4COVID is an ongoing prospective, active observational, post-authorisation cohort safety study (PASS) of UK-approved vaccines for COVID-19 disease.

SETTING

The study is conducted through a secure website (www.vac4covid.com) by MEMO Research, University of Dundee, UK.

PARTICIPANTS

16 265 adult (18 years or older) UK residents with a valid email address and internet access.

INTERVENTIONS

Any UK-authorised COVID-19 vaccination.

MAIN OUTCOME MEASURES

The outcomes reported in this interim analysis include AEs, reactogenicity-type AEs (headache, fatigue, muscle or joint pain, fever, nausea, dizziness or local vaccine reaction), menstrual changes and reported improvement in overall health and well-being.

RESULTS

11 475 consented participants (mean age 54.8 years) provided follow-up data between 2 February and 5 October 2021 (mean follow-up duration 184 days), by which date 89.2% of participants had received two vaccine doses. 89.8% of 5222 participants who completed a follow-up questionnaire in the 7 days after any COVID-19 vaccination reported no AEs. The risk of experiencing any event (not necessarily vaccine-related) requiring hospitalisation was less than 0.2%. 43.7% of post-vaccination follow-up records reported improvement in health and well-being. Reactogenicity-type reactions were more common in the week after the first dose of ChAdOx1 than BNT162b2 (7.8% vs 1.6%), but this relationship was reversed after the second dose (1.3% vs 3.1%). 0.3% of women reported menstrual symptoms after vaccination; no differences between vaccine type or dose order were detected.

CONCLUSIONS

The study provides reassuring data on low rates of AEs after COVID-19 vaccination. Differences in reactogenicity-type AE profiles between ChAdOx1 and BNT162b2 and between first and second doses of these vaccines were observed.

TRIAL REGISTRATION NUMBER

ISRCTN95881792; Pre-results.

Evaluating Diuretics in Normal Care (EVIDENCE): a feasibility report of a pilot cluster randomised trial of prescribing policy in primary care to compare the effectiveness of thiazide-type diuretics in hypertension

Background

Obtaining evidence on comparative effectiveness and safety of widely prescribed drugs in a timely and cost-effective way is a major challenge for healthcare systems. Here, we describe the feasibility of the Evaluating Diuretics in Normal Care (EVIDENCE) study that compares a thiazide and thiazide-like diuretics for hypertension as an exemplar of a more general framework for efficient generation of such evidence. In 2011, the UK NICE hypertension guideline included a recommendation that thiazide-like diuretics (such as indapamide) be used in preference to thiazide diuretics (such as bendroflumethiazide) for hypertension. There is sparse evidence backing this recommendation, and bendroflumethiazide remains widely used in the UK.

Methods

Patients prescribed indapamide or bendroflumethiazide regularly for hypertension were identified in participating general practices. Allocation of a prescribing policy favouring one of these drugs was then randomly applied to the practice and, where required to comply with the policy, repeat prescriptions switched by pharmacy staff. Patients were informed of the potential switch by letter and given the opportunity to opt out. Practice adherence to the randomised policy was assessed by measuring the amount of policy drug prescribed as a proportion of total combined indapamide and bendroflumethiazide. Routinely collected hospitalisation and death data in the NHS will be used to compare cardiovascular event rates between the two policies.

Results

This pilot recruited 30 primary care practices in five Scottish National Health Service (NHS) Boards. Fifteen practices were randomised to indapamide (2682 patients) and 15 to bendroflumethiazide (3437 patients), a study population of 6119 patients. Prior to randomisation, bendroflumethiazide was prescribed to 78% of patients prescribed either of these drugs. Only 1.6% of patients opted out of the proposed medication switch.

Conclusion

The pilot and subsequent recruitment confirms the methodology is scalable within NHS Scotland for a fully powered larger study; currently, 102 GP practices (> 12,700 patients) are participating in this study. It has the potential to efficiently produce externally valid comparative effectiveness data with minimal disruption to practice staff or patients. Streamlining this pragmatic trial approach has demonstrated the feasibility of a random prescribing policy design framework that can be adapted to other therapeutic areas.

Trial registration

ISRCTN Registry, ISRCTN46635087. Registered on 11 August 2017

Evaluating Diuretics in Normal Care (EVIDENCE): protocol of a cluster randomised controlled equivalence trial of prescribing policy to compare the effectiveness of thiazide-type diuretics in hypertension

INTRODUCTION

Healthcare systems must use treatments that are effective and safe. Regulators licensed many currently used older medications before introducing the stringent evidential requirements imposed on modern treatments. Also, there has been little encouragement to carry out within-class, head-to-head comparisons of licensed medicines. For commonly prescribed drugs, even small differences in effectiveness or safety could have significant public health implications. However, conventional clinical trials that randomise individual subjects are costly and unwieldy. Such trials are also often criticised as having low external validity. We describe an approach to rapidly generate externally valid evidence of comparative safety and effectiveness using the example of two widely used diuretics for the management of hypertension.

METHODS AND ANALYSIS

The EVIDENCE (Evaluating Diuretics in Normal Care) study has a prospective, cluster-randomised, open-label, blinded end-point design. By randomising prescribing policy in primary care practices, the study compares the safety and effectiveness of commonly used diuretics in treating hypertension. Participating practices are randomised 1:1 to a policy of prescribing either indapamide or bendroflumethiazide when clinically indicated. Suitable patients who are not already taking the policy diuretic are switched accordingly. All patients taking the study medications are written to explaining the rationale for changing the prescribing policy and notifying them they can opt-out of any switch. The prescribing policies' effectiveness and safety will be compared using rates of major adverse cardiovascular events (hospitalisation with myocardial infarction, heart failure or stroke or cardiovascular death), routinely collected in national healthcare administrative datasets. The study will seek to recruit 250 practices to provide a study population of approximately 50,000 individuals with a mean follow-up time of two years. A primary intention-to-treat time-to-event analysis will be used to estimate the relative effect of the two policies.

ETHICS AND DISSEMINATION

EVIDENCE has been approved by the East of Scotland Research Ethics Service (17/ES/0016, current approved protocol version 5, 26 August 2021). The results will be disseminated widely in peer reviewed journals, guideline committees, National Health Service (NHS) organisations and patient groups.

TRIAL REGISTRATION

ISRCTN 46635087 . Registered on 11 August 2017 (pre-recruitment).

Eosinophilic Gastroenteritis Causing Small Bowel Diverticulosis and Volvulus: A Case Report

Patient: Female, 83-year-old

Final Diagnosis: Eosinophilic gastroentritis • jejunal diverticulosis

Symptoms: Abdominal pain • obstruction

Medication: —

Clinical Procedure: —

Specialty: Surgery

Risk of infertility in female adolescents and young adults with cancer: a population-based cohort study

STUDY QUESTION

Do female adolescents and young adults (AYAs) with cancer have a higher risk of subsequent infertility diagnosis than AYAs without cancer?

SUMMARY ANSWER

Female AYAs with breast, hematological, thyroid and melanoma cancer have a higher risk of subsequent infertility diagnosis.

WHAT IS KNOWN ALREADY

Cancer therapies have improved substantially, leading to dramatic increases in survival. As survival improves, there is an increasing emphasis on optimizing the quality of life among cancer survivors. Many cancer therapies increase the risk of infertility, but we lack population-based studies that quantify the risk of subsequent infertility diagnosis in female AYAs with non-gynecological cancers. The literature is limited to population-based studies comparing pregnancy or birth rates after cancer against unexposed women, or smaller studies using markers of the ovarian reserve as a proxy of infertility among female survivors of cancer.

STUDY DESIGN, SIZE, DURATION

We conducted a population-based cohort study using universal health care databases in the province of Ontario, Canada. Using data from the Ontario Cancer Registry, we identified all women 15-39 years of age diagnosed with the most common cancers in AYAs (brain, breast, colorectal, leukemia, Hodgkin lymphoma, non-Hodgkin lymphoma, thyroid and melanoma) from 1992 to 2011 who lived at least 5 years recurrence-free (Exposed, n = 14,316). Women with a tubal ligation, bilateral oophorectomy or hysterectomy previous to their cancer diagnosis were excluded. We matched each exposed woman by age, census subdivision, and parity to five randomly selected unexposed women (n = 60,975) and followed subjects until 31 December 2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Infertility diagnosis after 1 year of cancer was identified using information on physician billing codes through the Ontario Health Insurance Plan database (ICD-9 628). Modified Poisson regression models were used to assess the risk of infertility diagnosis (relative risk, RR) adjusted for income quintile and further stratified by parity at the time of cancer diagnosis (nulliparous and parous).

MAIN RESULTS AND THE ROLE OF CHANCE

Mean age at cancer diagnosis was 31.4 years. Overall, the proportion of infertility diagnosis was higher in cancer survivors compared to unexposed women. Mean age of infertility diagnosis was similar among cancer survivors and unexposed women (34.8 years and 34.9 years, respectively). The overall risk of infertility diagnosis was higher in cancer survivors (RR 1.30; 95% CI 1.23-1.37). Differences in infertility risk varied by type of cancer. Survivors of breast cancer (RR 1.46; 95% CI 1.30-1.65), leukemia (RR 1.56; 95% CI 1.09-2.22), Hodgkin lymphoma (RR 1.49; 95% CI 1.28-1.74), non-Hodgkin lymphoma (RR 1.42; 95% CI 1.14, 1.76), thyroid cancer (RR 1.20; 95% CI 1.10-1.30) and melanoma (RR 1.17; 95% CI 1.01, 1.35) had a higher risk of infertility diagnosis compared to women without cancer. After stratification by parity, the association remained in nulliparous women survivors of breast cancer, leukemia, lymphoma and melanoma, whereas it was attenuated in parous women. In survivors of thyroid cancer, the association remained statistically significant in both nulliparous and parous women. In survivors of brain or colorectal cancer, the association was not significant, overall or after stratification by parity.

LIMITATIONS, REASONS FOR CAUTION

Non-biological factors that may influence the likelihood of seeking a fertility assessment may not be captured in administrative databases. The effects of additional risk factors, including cancer treatment, which may modify the associations, need to be assessed in future studies.

WIDER IMPLICATIONS OF THE FINDINGS

Reproductive health surveillance in female AYAs with cancer is a priority, especially those with breast cancer, leukemia and lymphoma. Our finding of a potential effects of thyroid cancer (subject to over-diagnosis) and, to a lesser extent, melanoma need to be further studied, and, if an effect is confirmed, possible mechanisms need to be elucidated.

STUDY FUNDING/COMPETING INTEREST(S)

Funding was provided by the Faculty of Health Sciences and Department of Obstetrics and Gynecology, Queen's University. There are no competing interests to declare.

TRIAL REGISTRATION NUMBER

N/A.

322. Evaluation of the BioFire® Bone and Joint Infection (BJI) Panel for the Detection of Microorganisms and Antimicrobial Resistance Genes in Synovial Fluid Specimens

Background

Bone and Joint Infections (BJIs) present with non-specific symptoms that may include pain, swelling, and fever and are associated with high morbidity and significant risk of mortality. BJIs can be caused by a variety of bacteria and fungi, including anaerobes and microorganisms that can be challenging to culture or identify by traditional microbiological methods. Clinicians primarily rely on culture to identify the pathogen(s) responsible for infection. The BioFire^® Bone and Joint Infection (BJI) Panel (BioFire Diagnostics, Salt Lake City, UT) is designed to detect 15 gram-positive bacteria (including seven anaerobes), 14 gram-negative bacteria (including one anaerobe), two yeast, and eight antimicrobial resistance (AMR) genes from synovial fluid specimens in about an hour. The objective of this study was to evaluate the performance of an Investigational Use Only (IUO) version of the BioFire BJI Panel compared to various reference methods.

Methods

Remnant synovial fluid specimens, which were collected for routine clinical care at 13 study sites in the US and Europe, underwent testing using an IUO version of the BioFire BJI Panel. Performance of this test was determined by comparison to Standard of Care (SoC) consisting of bacterial culture performed at each study site according to their routine procedures.

Results

A total of 1544 synovial fluid specimens were collected and tested with the BioFire BJI Panel. The majority of specimens were from knee joints (77.9%) and arthrocentesis (79.4%) was the most common collection method. Compared to SoC culture, overall sensitivity was 90.2% and specificity was 99.8%. The BioFire BJI Panel yielded a total of 268 Detected results, whereas SoC yielded a total of 215 positive results for on-panel analytes.

Conclusion

The BioFire BJI Panel is a sensitive, specific, and robust test for rapid detection of a wide range of analytes in synovial fluid specimens. The number of microorganisms and resistance genes included in the BioFire BJI Panel, together with a reduced time-to-result and increased diagnostic yield compared to culture, is expected to aid in the timely diagnosis and appropriate management of BJIs.

Disclosures

Benjamin von Bredow, PhD, BioFire (Grant/Research Support) Jennifer Dien Bard, PhD, BioFire Diagnostic (Consultant, Scientific Research Study Investigator) Bart Kensinger, PhD, BioFire Diagnostics (Employee) Benedicte Pons, PhD, bioMerieux SA (Employee) Corinne Jay, PhD, bioMerieux SA (Employee)

300. Pediatric Center Evaluation of the BioFire® Blood Culture Identification 2 Panel Versus the Original BioFire®FilmArray® Blood Culture Identification Panel for the Detection of Microorganisms and Resistance Markers in Positive Blood Cultures

Background

Studies show a rising annual incidence of severe sepsis, with bloodstream infections continuing to impact children. Rapid identification of causative agents and timely administration of targeted therapy can positively impact patient outcomes and improve antibiotic stewardship.

The BioFire^® Blood Culture Identification 2 (BCID2) Panel (BioFire Diagnostics, LLC), an updated version of the FDA-cleared BioFire^® FilmArray^® Blood Culture Identification (BCID) Panel, designed for use on positive blood cultures (PBCs), assesses 43 analytes, including 17 novel analytes (8 bacterial, 2 fungal, and 7 antimicrobial resistance genes), with a similar turnaround time.

Methods

De-identified residual PBCs for which clinician-ordered testing per standard of care (SoC) had been performed were enrolled and tested with an Investigation-Use-Only version of the BCID2 Panel. Only one positive bottle per patient was enrolled. Results of BCID2 and BCID were compared.

Results

116 PBCs (48 aerobic and 68 anaerobic) were evaluated using the BioFire BCID2 Panel and results were compared to the BioFire BCID Panel. Of the 116 cases, 103 were positive on both the BioFire BCID2 Panel and the BioFire BCID Panel. Ten cases were negative on both tests. While the two panels showed 97% agreement, three cases were discrepant. Using culture (SoC) as the tiebreaker, two cases were false positive and one case was false negative on the BioFire BCID Panel. In all three cases, results from culture and the BioFire BCID2 Panel were in agreement. As expected, no organisms were detected on the BioFire BCID2 Panel in PBCs from 10% (12/116) of PBC bottles where culture identified only organisms that are not part of the panel menu. With the BioFire BCID2 Panel’s expanded platform, two cases identified as Enterobacteriaceae on the BioFire BCID Panel were identified to the genus level on the BioFire BCID2 Panel; 31 cases detected to the genus level on the BioFire BCID Panel were identified to the species level on the BioFire BCID2 Panel.

Conclusion

Overall, the BioFire BCID2 Panel performed well against the BioFire BCID Panel for identification of bloodstream pathogens and provided additional discrimination of some pathogens to the genus or species level.

Data presented are from assays that have not been cleared or approved for diagnostic use.

Disclosures

All Authors: No reported disclosures

A high anticholinergic burden is associated with a history of falls in the previous year in middle-aged women: findings from the Aberdeen Prospective Osteoporosis Screening Study

PURPOSE

To examine the cross-sectional association between anticholinergic medication burden (ACB) and a history of falls, bone mineral density, and low trauma fractures in middle-aged women aged under 65 years from the Aberdeen Prospective Osteoporosis Screening Study.

METHODS

ACB (0 = none, 1 = possible, ≥2 = definite) was calculated from medication use for 3883 Caucasian women [mean age (SD) = 54.3 (2.3) years] attending the second Aberdeen Prospective Osteoporosis Screening Study visit (1997-2000). Outcomes were examined using logistic regression. Model adjustments were selected a priori based on expert opinion.

RESULTS

Of 3883 participants, 3293 scored ACB = 0, 328 scored ACB = 1, and 262 scored ACB ≥2. High ACB burden (≥2) was associated with increased odds (ACB = 0 reference) for falls (fully adjusted odds ratio [95% confidence intervals] = 1.81 [1.25-2.62]; P = 0.002) and having low bone mineral density (lowest quintile-20%) at Ward's triangle (3.22 [1.30-7.99]; P = 0.01). A history of falls over the year prior to the study visit in participants with ACB score ≥2 was 32 per 100. For ACB categories 1 and 0, a history of falls per 100 was 21 and 22, respectively.

CONCLUSIONS

The risk of falling associated with ACB observed in older age may also extend to middle-aged women.

Reproducing Clinically Significant Multi-Organism Cultures to Improve Clinical Microbiology Education and Practice

Medical microbiology courses focus on clinically relevant organisms, but designing laboratory experiments that mimic clinical specimens can be challenging. Many clinical specimens produce multi-organism cultures, which are difficult to reproducibly create in the academic laboratory. With experience with only single organism cultures, students may find it challenging to transition to the clinical laboratory where they must identify pathogens and normal flora from mixed cultures. Here, we present protocols for the creation of multi-organism cultures for mock wound, stool, urine, and throat cultures with medically relevant bacteria that allow these principles to be taught in an academic laboratory prior to clinical experiences.

Influence of Reading Materials on Response to Printed Words

Beginning reading materials differ considerably in the characteristics of words included in stories. While many reading texts are characterized by a limited number of words that vary in length and pattern, reading materials for phonics or linguistic instruction tend to contain a greater number of words that are similar in length and pattern. Examination of materials indicates that those with particular characteristics support learning by particular methods. This investigation explores the effect of word characteristics in reading materials on children's responses to printed words.

Development and validation of a generic scale for use in transition programmes to measure self-management skills in adolescents with chronic health conditions: the TRANSITION-Q

AIM

To develop a generic self-management skills scale for use with adolescents diagnosed with a chronic health condition who are aged 12 to 18 years.

BACKGROUND

There is a lack of methodologically sound scales for healthcare teams to use to measure self-management skills in adolescents with chronic conditions transitioning to adult care.

METHODS

Adolescents aged 12 to 18 years with a broad range of chronic health conditions, including neurodevelopmental conditions, were recruited from May to August 2013 from nine outpatient clinics at McMaster Children's Hospital (Canada). Thirty-two participated in a cognitive interview, and 337 completed a questionnaire booklet. Interviews were used to develop the TRANSITION-Q. Rasch measurement theory (RMT) analysis was used to identify items that represent the best indicators of self-management skills. Traditional psychometric tests of measurement performance were also conducted.

RESULTS

The response rate was 92% (32/32 cognitive; 337/371 field test). RMT analysis resulted in a 14-item scale with three response options. The overall fit of the observed data to that expected by the Rasch model was non-significant, providing support that this new scale measured a unidimensional construct. Other tests supported the scale as scientifically sound, e.g. Person Separation Index = 0.82; good item fit statistics; no differential item function by age or gender; low residual correlations between items; Cronbach's alpha = 0.85; test-retest reliability = 0.90; and tests of construct validity that showed, as hypothesized, fewer skills in younger participants and in participants who required assistance to complete the scale. Finally, participants who agreed they are ready to transfer to adult healthcare reported higher TRANSITION-Q scores than did participants who disagreed.

CONCLUSIONS

The TRANSITION-Q is a short, clinically meaningful and psychometrically sound scale. This generic scale can be used in research and in paediatric and adolescent clinics to help evaluate readiness for transition.

Treatment of childhood acute lymphoblastic leukemia in central America: a lower-middle income countries experience

BACKGROUND

Five Asociación de Hemato-Oncología de Centroamérica (AHOPCA) countries have used an adapted BFM-based protocol for childhood acute lymphoblastic leukemia (ALL).

PROCEDURE

In the AHOPCA-ALL 2008 protocol, patients were stratified by age, white blood cell count, immunophenotype, central nervous system involvement, day 8 prednisone response, and morphologic bone marrow response to induction therapy. Patients at Standard Risk (SR) received a three-drug induction regimen, a reinduction phase, and maintenance with protracted intrathecal therapy. Those at Intermediate (IR) and High Risk (HR) received, in addition, daunorubicin during induction therapy, a consolidation phase and two or three reinduction phases respectively.

RESULTS

From August 2008 through July 2012, 1,313 patients were enrolled: 353 in SR, 548 in IR, 412 in HR. During induction therapy, 3.0% of patients died, 2.7% abandoned treatment, 1.1% had resistant ALL, and 93.2% achieved morphological complete remission (CR). Deaths and abandonment in first CR occurred in 2.7% and in 7.0% of patients, respectively. The relapse rate at a median observation time of 2.1 years was 15.0%. At 3 years, the event-free survival (EFS) and overall survival (OS), with abandonment considered as an event, were 59.4% (SE 1.7) and 68.2% (SE 1.6). Three-year EFS was 68.5% (SE 3.0), 62.1% (SE 2.6), and 47.8% (SE 3.2) for SR, IR, and HR groups. Adolescents had a significantly higher relapse rate (P = 0.001).

CONCLUSIONS

This experience shows that common international studies are feasible in lower-middle income countries. Toxic deaths, abandonment of treatment, and relapses remain major obstacles to the successful treatment. Alternative treatment strategies may be beneficial.

Economic evaluation of treatment for acute lymphoblastic leukaemia in childhood

Berlin-Frankfurt-Munster (BFM) and Dana-Farber Cancer Institute (DFCI) consortia's treatment strategies for acute lymphoblastic leukaemia (ALL) in children are widely used. We compared the health effects and monetary costs of hospital treatments for these two strategies. Parents of children treated at seven centres in Canada, Italy and the USA completed health-related quality of life (HRQL) assessments during four active treatment phases and at 2 years after treatment. Mean HRQL scores were used to calculate quality-adjusted life years (QALYs) for a period of 5 years following diagnosis. Total costs of treatment were determined from variables in administrative databases in a universally accessible and publicly funded healthcare system. Valid HRQL assessments (n = 1200) were collected for 307 BFM and 317 DFCI patients, with costs measured for 66 BFM and 28 DFCI patients. QALYs per patient were <1.0% greater for BFM than DFCI. Median HRQL scores revealed no difference in QALYs. The difference in mean total costs for BFM (US$88 480) and DFCI (US$93 026) was not significant (P = 0.600). This study provides no evidence of superiority for one treatment strategy over the other. Current BFM or DFCI strategies should represent conventional management for the next economic evaluation of treatments for ALL in childhood.

Health-related quality of life during post-induction chemotherapy in children with acute lymphoblastic leukemia in remission

Using a multi-attribute approach, we and others have reported on the comprehensive health status of survivors of cancer in childhood, after completion of therapy. However, there is a dearth of information about health status and associated health-related quality of life (HRQL) in children and adults with cancer, during the treatment process; a deficit which this study was intended to redress. All children (n=18) receiving 'maintenance' chemotherapy for acute lymphoblastic leukemia (ALL) at a single institution were assessed prospectively through a single cycle of therapy. Patients, family members and health care professionals used global ratings, the health utilities index mark 2 (HUI2) and mark 3 (HUI3) classification systems, and detailed descriptions of temporary states of health, to provide independent assessments of health status at weekly intervals. Utility scores were derived for each comprehensive health state and for single attribute levels of the HUI2 system, and for the temporary health state descriptions. The classification of the subjects into the most appropriate temporary health states was challenging even for older children and some of the parents. The HUI instruments were used much more easily and produced highly comparable information. The most frequently affected attributes were pain, emotion and mobility/ambulation; in that order. The global (p=0.005) and specific morbidity burdens were, as predicted, greatest in the middle of the cycle of chemotherapy, reflecting the toxicity of steroid use. HUI2 global utility scores demonstrated moderate responsiveness with an intra-class correlation coefficient of 0.43. Cyclical administration of therapy, in particular corticosteroids, produces important changes in health status and HRQL in children with ALL. The HUI are valid and responsive systems for quantifying the burden of morbidity during the treatment of cancer in childhood. These are sensitive tools which can be used in a wide array of other circumstances to quantify changes in health status.

The monetary costs of childhood cancer to the families of patients

The medical costs of cancer treatment are well described, but there are few reports of expenses incurred by families of children with malignant disease. The objective of this study was to describe the monetary costs borne by families of patients with childhood cancer and to determine whether these costs represent an important component of the burden of illness. Families completed a prospective diary survey about daily expenses incurred during each sample week of therapy. We also undertook a retrospective, cross-sectional questionnaire survey about expenses, incurred during the entire duration of treatment, associated with major or one-time cost items. Seventy families of children treated for high risk acute lymphoblastic leukemia, 19 families of children treated for Wilms' tumor stages 2-5, and 16 families of children treated for neuroblastoma stages 3 and 4 completed diaries or questionnaires detailing the costs resulting from the diseases and their treatment. The mean total expenses (in 1986 Canadian dollars) incurred by families of childhood cancer patients over the entire course of therapy are $26,070 for acute lymphoblastic leukemia? $20,074 for Wilms' tumour, and $10,376 for neuroblastoma. On-going weekly costs rather than major one-time purchases account for the largest share of expenses. Overall, in spite of universal first dollar coverage for medical care in Canada, family-borne costs during the course of these illnesses are at least one-third of the average family's after-tax income.

A multiattribute approach to health-status measurement and clinical management illustrated by an application to brain-tumors in childhood

A comprehensive multi-attribute system was devised to assess global morbidity burden. The system was used to obtain qualitative and quantitative measures of health-status for a case series of survivors of brain tumors in childhood. Health-related quality-of-life scores for each global health-state were calculated from a utility function derived from measures of preferences collected during surveys of a random sample of parents of school age children in the general public (n=194). Global multi-attribute health status (MAHS) utility scores revealed a wide range of severity in morbidity burden. We suggest that the assessment of health-related quality-of-life should become an integral part of clinical management.

Bleeding disorders, menorrhagia and iron deficiency: impacts on health-related quality of life

von Willebrand disease (VWD) is a bleeding disorder that occurs in up to 1% of the general population. The great majority of females with VWD experience menorrhagia. The morbidity burden in females with VWD may relate to iron deficiency resulting from menorrhagia. To explore relationships between bleeding disorders, menorrhagia, iron deficiency and the outcomes of health-related quality of life (HRQL) and educational attainment. All subjects with VWD, and females with other bleeding disorders, in the Canadian national registry who were more than 12 years of age were eligible for survey. Survey measures included the HEALTH UTILITIES INDEX(®); abridged Clinical History Assessment Tool; socio-demographic questions and serum ferritin. Statistical analyses included testing differences among groups of means using analysis of variance and of proportions using chi-squared test. Significant size differences in mean HRQL scores were detected between VWD females and both females with other bleeding disorders [diff = (-0.08); P = 0.017] and VWD males [diff = (-0.07); P = 0.039]. Mean HRQL scores differed between females with and without menorrhagia (P < 0.001). Mean HRQL scores were not significantly different between females with and without iron deficiency. Educational attainment was not associated with disease group, menorrhagia status or iron status. Females with VWD have a greater morbidity burden than females in the general population, females with other bleeding disorders and males with VWD. Menorrhagia is associated with low HRQL scores in females with bleeding disorders, including VWD. Further investigation should assess how menorrhagia impacts HRQL in females with bleeding disorders.

Association between vitamin D receptor gene polymorphisms, falls, balance and muscle power: results from two independent studies (APOSS and OPUS)

SUMMARY

Fall prevention is a key strategy for reducing osteoporotic fractures. We investigated the association between vitamin D receptor (VDR) polymorphisms and reported falls in postmenopausal women. Bsm1 polymorphisms were associated with falls, balance and muscle power measurements. These results may explain some of the excess fracture risk associated with VDR in some studies.

INTRODUCTION

Fall prevention is a key strategy for reducing osteoporotic fractures. It has been suggested that vitamin D supplementation may reduce the incidence of falls by reducing body sway and increasing muscle power. The vitamin D receptor gene is a well-studied candidate gene for osteoporosis. We investigated the association between VDR polymorphisms and reported falls in postmenopausal women.

METHODS

Falls data were collected in two separate population cohorts. Five polymorphisms of the VDR gene were analysed (Cdx-2, Fok-1, BsmI, Taq1 and Apa1) in the Aberdeen Prospective Osteoporosis Screening Study (APOSS) cohort. Results found in APOSS were then validated in an independent cohort--the Osteoporosis and Ultrasound (OPUS) study (Bsm1 and Fok1 only), where muscle power and balance were also measured.

RESULTS

Carriers of the 'B' allele (Bsm1) showed an increased risk for falls. In APOSS, this was statistically significant for visit 3 multiple falls (p = 0.047) and for recurrent falls (p = 0.043). Similar results were found in OPUS for visit 1 falls (p = 0.025) and visit 1 multiple falls (p = 0.015). Bsm1 polymorphisms were also associated with balance and muscle power measurements.

CONCLUSIONS

In conclusion, these results demonstrate an association between the Bsm1 polymorphism and risk of falling that may explain some of the excess fracture risk associated with VDR in some studies.

Incidence and predictors of treatment-related mortality in paediatric acute leukaemia in El Salvador

Survival rates among children with leukaemia in low-income countries are lower than those in high-income countries. This has been attributed in part to higher treatment-related mortality (TRM). We examined the demographics, treatment, and outcomes of paediatric patients in El Salvador with acute lymphoblastic leukaemia (ALL) or acute myeloid leukaemia (AML) to determine the incidence, causes, and risk factors for TRM. Two trained data managers collected data prospectively; no patients were excluded. Biological, socioeconomic and nutritional predictors were examined. A total of 469 patients with ALL and 78 patients with AML were included. The 2-year cumulative incidence of TRM was significantly higher among children with AML (35.4±6.4%) than those with ALL (12.5±1.7%; P<0.0001). However, the proportion of deaths attributable to the toxicity of treatment did not differ significantly between AML (25/47, 53.2%) and ALL (55/107, 51.4%; P=0.98). Among children with ALL, low monthly income (P=0.04) and low parental education (P=0.02) significantly increased the risk of TRM. Among children with AML, biological, socioeconomic, and nutritional variables were not associated with TRM. In this low-income country, toxic death significantly contributes to mortality in both ALL and AML. A better understanding of the effect of socioeconomic status on TRM may suggest specific strategies for patients with ALL.

Bone mineral status after treatment of malignant lymphoma in childhood and adolescence

The relationship between bone mineral mass and cumulative dose of corticosteroids (CDC) was investigated in 42 children and adolescents treated for Hodgkin disease (HD; n = 22) and non-Hodgkin lymphoma (NHL; n = 20). The median age at the time of the study was 24.1 years for HD survivors and 14.1 years for NHL survivors. Dual-energy X-ray absorptiometry [bone mineral density of the lumbar spine (LS-BMD) expressed as Z-scores] and peripheral quantitative computed tomography at the distal radius [trabecular volumetric BMD (vBMD-trab)] were undertaken. Osteopenia (Z-score < -1.00) was found in 9/22 patients with HD and 10/20 with NHL, while 34% (HD = 6, NHL = 8) had a vBMD-trab below the normal range. The CDC correlated inversely with LS-BMD Z-score (r =-0.41, P = 0.007). There was a statistically significantly higher vBMD-trab in patients who received low (1-4 g/m(2)) compared with high (>or=20 g/m(2)) CDC (P = 0.031). Treatment of malignant lymphoma with high CDC is a risk factor for development of osteopenia.

Loss to follow-up of patients with malignant lymphoma

Loss to follow-up (LTFU) in cancer patients is a serious problem, yet there is little data on this and on the underlying reasons. Of 144 paediatric and 431 adult patients with lymphoma diagnosed in 1997/1998 at King Faisal Specialist Hospital and Research Center, Riyadh (KFSHRC), 30% and 48.5%, respectively, were LTFU after 4 years (excluding patients known to have died). In 2001-2002, 196 paediatric and adult lymphoma patients at KFSHRC were enrolled in a prospective study in which explanations were obtained in detail for non-attendance at follow-up appointments (No Show). Sixteen months after commencement of the study, 49 patients were No Show, because of patient-based communication problems (20), transportation problems (8), patient not contactable (18), and personal reasons (3). In addition, patients were recorded incorrectly as No Show through hospital/patient communication problems. The No Show patients, especially the 23 who failed to keep a second appointment, are identifiable as potential LTFU during the 3 years in which this cohort will be followed. This study and, we suggest, other studies on LTFU should stimulate interest in this issue, in the predisposing factors, and in strategies to address them.

The effects of dietary fatty acid supplementation on endothelial function and vascular tone in healthy subjects

OBJECTIVE

Evaluation of the effects of supplementation of n-3 and n-6 fatty acids on vascular tone and endothelial function in healthy men and women aged 40 to 65 years.

METHODS

In a double-blind, randomised, placebo controlled study, 173 healthy volunteers took one of six oil supplements for 8 months. Supplements were placebo, oleic acid rich sunflower oil, evening primrose oil, soya bean oil, tuna fish oil, and tuna/evening primrose oil mix. Endothelium-dependent and independent vascular responses were measured in the forearm skin using laser Doppler imaging following iontophoretic applications of acetylcholine and sodium nitroprusside, respectively.

RESULTS

Acetylcholine, but not sodium nitroprusside responses were significantly improved after tuna oil supplementation (P=0.02). Additionally, there were significant positive correlations between acetylcholine responses and n-3 fatty acid levels in the plasma and erythrocyte membrane phospholipids after tuna oil supplementation. No significant changes in vascular response were seen after supplementation with any of the other oils.

CONCLUSIONS

Fish oil supplementation has a beneficial effect on endothelial function, even in normal healthy subjects. Modification of the diet by an increase of 6% in eicosapentaenoic acid and 27% in docosahexaenoic acid (equivalent to eating oily fish 2-3 times/week) might have significant beneficial effects on cardiovascular function and health.

Seeking consensus: contrast ultrasound in radiology

This paper summarises the discussions from a meeting held on contrast ultrasound held on 21 October 2000 in Toronto, Canada. The aims of this meeting, supported by ATL/Philips Ultrasound, was to review the current clinical indications for contrast usage in the liver and kidney, arrive at recommendations for use of intravenous contrast agents, and speculate on the future uses. This paper is published to help understand this rapidly evolving field. Consensus points included a recommendation that Levovist in its post-vascular phase was of considerable value in detecting and excluding metastases in the liver, although unlikely realistically to replace CT or MR. Newer agents such as Sonovue, Definity and Sonazoid, suitable for low mechanical index (MI) imaging were also of great value and may have a further role for HCC detection. Equipment manufacturers should strive to keep improving low mechanical index modes for these agents. Promising applications for characterisation included further evaluation of lesions discovered on ultrasound and as a problem solver for CT or MR. To date no contrast agents have received approval from the FDA for radiological applications in the United States. The case for reimbursement for contrast agents was strongly supported by the panel.

Childhood cancer in Uruguay: 1992-1994. Incidence and mortality

BACKGROUND

The referral of all children with cancer in Uruguay to a single center affords the opportunity to generate population-based incidence and mortality rates in this developing country in Latin America.

PROCEDURE

All incident cases of cancer in children, 0-14 years of age, were ascertained from a combination of three sources for the period January 1992-December 1994. Diagnoses were grouped according to the International Classification of Childhood Cancer. Information on the size and age distribution of the total population was obtained from national census records. Follow-up was undertaken until December 1999 to afford a minimum interval of 5 years and the determination of mortality rates.

RESULTS

The average annual incidence was 133.6 cases of cancer per million children per year and the disease distribution was similar to that in industrialized countries, with the exception of a higher rate and younger age distribution for the Hodgkin disease. The overall age-standardized mortality rate from cancer in childhood, at 6.5 per 100,000, was approximately twice that in the United States and Canada.

CONCLUSIONS

Basic indicators of development suggest that Uruguay is more akin to the countries of North America and Western Europe than to those in the developing world. An opportunity has been identified to improve the outcome for children with cancer in this country.

Methodological issues in the development of a national database for primary care groups and trusts

At the National Primary Care Research and Development Centre (NPCRDC) we have constructed a national database for all primary care groups (PCGs) in England. At its core, the database links information about population socio-economic and demographic characteristics to generic health status and to the organisation, resourcing and activities of general practice. In this paper we describe and discuss the problems with linking these data, and with defining the boundaries and the local populations of PCGs, given that they have been established on the basis of administrative expediency rather than geographical coherence. We then consider the implications of these difficulties for needs assessment in primary care groups.

Mediated imitation in 6-month-olds: remembering by association

In two experiments with 72 6-month-olds, we examined whether associating an imitation task with an operant task affects infants' memory for either task. In Experiment 1, infants who imitated target actions that were modeled for 60 s on a hand puppet remembered them for only 1 day. We hypothesized that if infants associated the puppet imitation task with a longer-remembered operant task, then they might remember it longer too. In Experiment 2, infants learned to press a lever to activate a miniature train-a task 6-month-olds remember for 2 weeks-and saw the target actions modeled immediately afterward. These infants successfully imitated for up to 2 weeks, but only if the train memory was retrieved first. A follow-up experiment revealed that the learned association was bidirectional. This is the first demonstration of mediated imitation in 6-month-olds across two very different paradigms and reveals that associations are an important means of protracting memories.

Angiogenesis inhibitor TNP-470 during bone marrow transplant: safety in a preclinical model

High-dose therapy with stem cell rescue is a treatment option for patients with advanced solid tumors. Although this approach has promise for some pediatric cancers, especially neuroblastoma, it is limited by the risk of relapse posttransplant as well as concern about possible reinfused tumor cells in autologous stem cell products. Antiangiogenic agents given during and after recovery from high-dose therapy with stem cell rescue may decrease the risk of relapse. TNP-470 is an antiangiogenic agent now in clinical trials. Although it inhibits the growth of bone marrow (BM) colony-forming cells in vitro, no significant hematological toxicity has been seen in Phase I trials. To assess the feasibility of using antiangiogenic agents during the period of posttransplant hematopoietic engraftment, we have developed a model of stem cell transplant in mice. Mice were lethally irradiated and then rescued with stem cells containing a transgene expressed in the hematopoietic lineage. Mice were then treated with TNP-470 or placebo, and assessed for survival, successful engraftment, and kinetics of engraftment. Both treated and control mice demonstrated reliable multilineage engraftment as well as normal lymphoid maturation with no excess mortality in the treated group. WBCs were lower but still within the normal range at d+28 in mice treated with bolus TNP-470, but not in those treated with continuous infusion TNP-470, compared with controls. These data indicate that inhibitors of angiogenesis do not adversely impact engraftment after stem cell transplantation.

The angiogenesis inhibitor tnp-470 effectively inhibits human neuroblastoma xenograft growth, especially in the setting of subclinical disease

Tumor vascularity is highly correlated with disease outcome in neuroblastoma. Thus, novel therapeutics that target the vascular endothelium are candidates for incorporation into clinical trials. We therefore examined the effect of TNP-470 on human neuroblastoma growth in mouse models reflecting both clinically evident and minimal disease. Mice were inoculated s.c. or by tail vein injection with 10(7) human neuroblastoma-derived CHP-134 cells and treated with TNP-470 (100 mg/kg/dose s.c. three times a week or by continuous infusion) or saline. Treatment was given as a single agent in established xenografts, 10 days after 450 mg/kg of cyclophosphamide, or 12 h after tumor inoculation. Tumor growth rate was markedly inhibited in mice receiving TNP-470 administered alone both s.c. and by continuous infusion with a treatment to control ratio (T:C) at day 16 of 0.3 (P < 0.001) and a T:C at day 30 of 0.4 (P = 0.029) for each dosing method, respectively. TNP-470 also significantly inhibited tumor growth when administered following cyclophosphamide (T:C at day 30 = 0.2, P < 0.001) and inhibited disease establishment when given shortly after xenograft inoculation (T:C at day 30 = 0.1, P < 0.001) or tail vein injection. TNP-470 was shown to directly inhibit angiogenesis by Matrigel assay (P =.010) and to increase the apoptotic index in treated tumors. These data show that TNP-470 is a potent inhibitor of human neuroblastoma growth rate and tumorigenicity. We speculate that TNP-470 may be a useful adjuvant therapy for high-risk neuroblastoma patients, particularly when used in settings of minimal disease status.

Significance of minimal or no intraperitoneal fluid visible on CT scan associated with blunt liver and splenic injuries: a multicenter analysis

BACKGROUND

The use of ultrasound (U/S) for the evaluation of patients with blunt abdominal trauma is gaining increasing acceptance. Patients who would have undergone computed tomographic (CT) scan may now be evaluated solely with U/S. Solid organ injuries with minimal or no free fluid may be missed by surgeon sonographers.

OBJECTIVE

The purpose of this study was to describe the incidence and clinical importance of liver and splenic injuries with minimal or no free intraperitoneal fluid visible on CT scan. We hypothesized that these solid organ injuries occur infrequently and are of minor clinical significance.

METHODS

Patient records and CT scans were reviewed for the presence of and outcome associated with blunt liver and splenic injuries with minimal (<250 mL) or no free fluid detected by an attending radiologist. Data were collected from six major trauma centers during a 4-year period before the introduction of U/S and included demographics, grade of injury (American Association for the Surgery of Trauma scale), need for operative intervention, and outcome.

RESULTS

A total of 938 patients with liver and splenic injuries were identified. In this group, 11% of liver injuries and 12% of splenic injuries had no free fluid visible on CT scan and could be missed by diagnostic peritoneal lavage or U/S. Of the 938 patients, 267 (28%) met the inclusion criteria; 161 had injury to the spleen and 125 had injury to the liver. In the 267 patients studied, 97% of the injuries were managed nonoperatively. However, 8 patients (3%) required operative intervention for bleeding. Compared with the liver, the spleen was significantly more likely to bleed (p = 0.01), but the grade of splenic injury was not related to the risk for hemorrhage (p = 0.051).

CONCLUSION

Data from this study suggest that injuries to the liver or spleen with minimal or no intraperitoneal fluid visible on CT scan occur more frequently than predicted but usually are of minimal clinical significance. However, patients with splenic injuries may be missed by abdominal U/S. We found a 5% associated risk of bleeding. Therefore, abdominal U/S should not be used as the sole diagnostic modality in all stable patients at risk for blunt abdominal injury.

Characterization of rat liver malonyl-CoA decarboxylase and the study of its role in regulating fatty acid metabolism

In the liver, malonyl-CoA is central to many cellular processes, including both fatty acid biosynthesis and oxidation. Malonyl-CoA decarboxylase (MCD) is involved in the control of cellular malonyl-CoA levels, and functions to decarboxylate malonyl-CoA to acetyl-CoA. MCD may play an essential role in regulating energy utilization in the liver by regulating malonyl-CoA levels in response to various nutritional or pathological states. The purpose of the present study was to investigate the role of liver MCD in the regulation of fatty acid oxidation in situations where lipid metabolism is altered. A single MCD enzyme of molecular mass 50.7 kDa was purified from rat liver using a sequential column chromatography procedure and the cDNA was subsequently cloned and sequenced. The liver MCD cDNA was identical to rat pancreatic beta-cell MCD cDNA, and contained two potential translational start sites, producing proteins of 50.7 kDa and 54.7 kDa. Western blot analysis using polyclonal antibodies generated against rat liver MCD showed that the 50.7 kDa isoform of MCD is most abundant in heart and liver, and of relatively low abundance in skeletal muscle (despite elevated MCD transcript levels in skeletal muscle). Tissue distribution experiments demonstrated that the pancreas is the only rat tissue so far identified that contains both the 50.7 kDa and 54. 7 kDa isoforms of MCD. In addition, transfection of the full-length rat liver MCD cDNA into COS cells produced two isoforms of MCD. This indicated either that both initiating methionines are functionally active, generating two proteins, or that the 54.7 kDa isoform is the only MCD protein translated and removal of the putative mitochondrial targeting pre-sequence generates a protein of approx. 50.7 kDa in size. To address this, we transiently transfected a mutated MCD expression plasmid (second ATG to GCG) into COS-7 cells and performed Western blot analysis using our anti-MCD antibody. Western blot analysis revealed that two isoforms of MCD were still present, demonstrating that the second ATG may not be responsible for translation of the 50.7 kDa isoform of MCD. These data also suggest that the smaller isoform of MCD may originate from intracellular processing. To ascertain the functional role of the 50. 7 kDa isoform of rat liver MCD, we measured liver MCD activity and expression in rats subjected to conditions which are known to alter fatty acid metabolism. The activity of MCD was significantly elevated under conditions in which hepatic fatty acid oxidation is known to increase, such as streptozotocin-induced diabetes or following a 48 h fast. A 2-fold increase in expression was observed in the streptozotocin-diabetic rats compared with control rats. In addition, MCD activity was shown to be enhanced by alkaline phosphatase treatment, suggesting phosphorylation-related control of the enzyme. Taken together, our data demonstrate that rat liver expresses a 50.7 kDa form of MCD which does not originate from the second methionine of the cDNA sequence. This MCD is regulated by at least two mechanisms (only one of which is phosphorylation), and its activity and expression are increased under conditions where fatty acid oxidation increases.

Touch-Sensitive NADH Oxidase Activity of Pea and Cucumber Tendrils and Soybean Hypocotyl Sections

The cell surface reduced nicotinamide adenine dinucleotide (NADH) oxidase activity of soybean stems and of pea and cucumber tendrils responded to touch with a several-fold increase in activity. The increase in NADH oxidase persisted for 20 min or longer, and further touch stimulation during this period did not alter activity. With soybean sections, the specific activities in response to touch approximated those achieved maximally by auxin. Where the NADH oxidase was fully stimulated by 2,4-d, the NADH oxidase failed to respond further to touch. The findings indicate that the NADH oxidase of the plant cell surface is involved in the growth response to touch and in tendril coiling.

Population screening for hemochromatosis: a comparison of unbound iron-binding capacity, transferrin saturation, and C282Y genotyping in 5,211 voluntary blood donors

Early diagnosis and treatment of hemochromatosis is essential to prevent organ damage. Screening strategies to detect early hemochromatosis include testing for iron overload and/or genetic testing. Voluntary blood donors numbering 5,211 were screened with unbound iron-binding capacity (UIBC), transferrin saturation (TS), and genetic testing for the C282Y mutation of the HFE gene. The study found 16 C282Y homozygotes (1 in 327), 69 compound heterozygotes, 371 simple heterozygotes, and 4,755 normals. There were 5 men and 11 women homozygotes with a mean age of 42, range 28 to 57. Mean UIBC (24 +/- 7 microL) and TS (48% +/- 17%) in homozygotes were significantly different from compound heterozygotes, simple heterozygotes, and normals (ANOVA). Only 3 homozygotes had an elevated serum ferritin. Family studies found an additional 4 iron-loaded homozygotes. Optimal thresholds were < or =28 micromol/L for UIBC and > or =46% for TS. Receiver operating characteristic (ROC) curve analysis showed an area under the curve for UIBC of 0.93 (0. 85-1.0, 95% confidence interval), and for TS of 0.83 (0.7-0.95). Screening with UIBC to preselect those for genotyping is a cost-efficient strategy for population screening for hemochromatosis.

The development of declarative memory in human infants: age-related changes in deferred imitation

In 2 experiments, deferred imitation procedures were used to trace age-related changes in declarative memory by human infants over the first 2 years of life. An adult modeled 3 actions with an object, and infants' ability to reproduce those actions was assessed 24 hr later. Some infants were tested with a new object or in a new context relative to the original demonstration. Changes in the context disrupted the performance of 6-month-olds but had no effect on the performance of 12- and 18-month-olds. Changes in the object disrupted the performance of 6- and 12-month-olds but had no effect on the performance of 18-month-olds. This age-related increase in representational flexibility may account for the decline of childhood amnesia during the 3rd year of life.