Validity, reliability and discriminative capacity of an electronic quality of life instrument (Pelican) for childhood asthma in the Netherlands

PURPOSE

To assess psychometric properties of the Pelican instrument, an online Dutch self-administered Quality of Life instrument for childhood asthma for scientific and clinical use.

METHODS

A cohort study was done in two asthma populations and healthy children. One asthma population had assessment at start, 4 and 8 weeks. The other asthma population and healthy children had one assessment. All children were aged 6-12 years. Children completed the Pelican instrument, Paediatric Asthma Quality of Life Questionnaire, feeling thermometer and Childhood Asthma Control Test. Lung function and fraction exhaled nitric oxide were measured. Parents completed Functional Status II, Asthma Control Questionnaire, Childhood Asthma Control Test questionnaires and symptom diaries. We assessed interpretability, structural validity, internal consistency, reliability, construct and discriminative validity of the Pelican instrument.

RESULTS

Eighty-five asthmatic (mean age 8.5 years) and 49 healthy children (mean age 8.4 years) participated. The Pelican instrument has 5 domains with 21 items after factor analysis. Internal consistency was 0.89 (CI 0.85-0.92), domain reliability showed Cronbach's α's from 0.64 to 0.76 and item-to-scale correlations from 0.61 to 0.81. Test-retest reliability was confirmed ICC = 0.88 (CI 0.79-0.93). Construct validity was demonstrated by significant moderate correlations with other relevant asthma outcomes like PAQLQ (r = -0.59, p < 0.01). Discriminative capacity between controlled or uncontrolled asthma (t = 3.20, p < 0.01, Δ = 0.64) and asthma versus healthy subjects (t = 6.31, p < 0.01, Δ = 0.94) was found.

CONCLUSIONS

The psychometric properties of the Pelican instrument were acceptable in Dutch paediatric asthma patients between 6 and 12 years old.

Increase in Salmonella enterica serovar Paratyphi A infections in Phnom Penh, Cambodia, January 2011 to August 2013

We report an increased number of Salmonella enterica Paratyphi A infections in adults in Cambodia. Between January 2011 and August 2013, 71 S. Paratyphi A isolates were recovered from blood cultures, representing a 44-fold increase compared to July 2007 to December 2010, while monthly numbers of cultures did not change. Infections with S. Typhi increased two-fold in the same period. Most cases came from the capital Phnom Penh. These findings warrant epidemiological investigation to support public health measures.

Epidemic increase in Salmonella bloodstream infection in children, Bwamanda, the Democratic Republic of Congo

Salmonella enterica is the leading cause of bloodstream infection in children in sub-Saharan Africa, but few data are available from Central-Africa. We documented during the period November 2011 to May 2012 an epidemic increase in invasive Salmonella bloodstream infections in HGR Bwamanda, a referral hospital in Equateur Province, DR Congo. Salmonella spp. represented 90.4 % (103 out of 114) of clinically significant blood culture isolates and comprised Salmonella Typhimurium (54.4 %, 56 out of 103), Salmonella Enteritidis (28.2 %, 29 out of 103) and Salmonella Typhi (17.5 %, 18 out of 103), with Salmonella Enteritidis accounting for most of the increase. Most (82 out of 103, 79.6 %) isolates were obtained from children < 5 years old. Median ages of patients infected with Salmonella Typhimurium and Salmonella Enteritidis were 14 months (14 days to 64 years) and 19 months (3 months to 8 years) respectively. Clinical presentation was non-specific; the in-hospital case fatality rate was 11.1 %. More than two thirds (69.7 %, 53 out of 76) of children < 5 years for whom laboratory data were available had Plasmodium falciparum infection. Most (83/85, 97.6 %) non-typhoid Salmonella isolates as well as 6/18 (33.3 %) Salmonella Typhi isolates were multidrug resistant (i.e. resistant to the first-line oral antibiotics amoxicillin, trimethoprim-sulfamethoxazole and chloramphenicol), one (1.0 %) Salmonella Typhimurium had decreased ciprofloxacin susceptibility owing to a point mutation in the gyrA gene (Gly81Cys). Multilocus variable-number tandem-repeat (MLVA) analysis of the Salmonella Enteritidis isolates revealed closely related patterns comprising three major and four minor profiles, with differences limited to one out of five loci. These data show an epidemic increase in clonally related multidrug-resistant Salmonella bloodstream infection in children in DR Congo.

Six-year follow-up study of bone mineral density in patients with systemic lupus erythematosus

Long-term bone mineral density (BMD) changes and the associated factors in systemic lupus erythematosus (SLE) patients were assessed. Despite the remarkably low overall bone loss, significant spine bone loss was associated with the use of glucocorticoids, use of antimalarials, and lower 25-hydroxyvitamin D levels, stressing the importance of prevention of osteoporosis and vitamin D deficiency in SLE patients.

INTRODUCTION

The aim of this study is to assess the BMD changes in patients with SLE and to identify the associated factors.

METHODS

Demographic and clinical data of 126 SLE patients were collected, and BMD measurements of the lumbar spine and the total hip were performed by dual-energy X-ray absorptiometry at baseline and follow-up. Statistical analyses were performed using independent Mann-Whitney U tests and linear regression analyses.

RESULTS

At baseline, 39.7 % of the patients (90 % female, mean age 39 ± 12.2 years) had osteopenia, and 6.3 % had osteoporosis. The median follow-up duration was 6.7 years (range 1.9-9.3 years). Mean changes in BMD at the lumbar spine (-0.08 %/year) and the hip (-0.20 %/year) were not significant. During follow-up, 70 % of the patients used glucocorticoids. The mean ± SD daily glucocorticoid dose was 5.0 ± 5.0 mg. In multiple regression analysis, BMD loss at the spine was significantly associated with higher daily glucocorticoid dose and lower baseline 25-hydroxyvitamin D levels. BMD loss at the hip was associated with lower 25-hydroxyvitamin D levels at baseline, reduction of body mass index, and baseline use of antimalarials.

CONCLUSIONS

In this 6-year follow-up study, bone loss was remarkably low. A dose-dependent relationship between glucocorticoid use and spinal bone loss was found. In addition, the use of antimalarials and lower 25-hydroxyvitamin D levels at baseline were associated with BMD loss. These findings underline the importance of prevention and treatment of vitamin D deficiency and osteoporosis in SLE, especially in patients using glucocorticoids or antimalarials.

Malaria rapid diagnostic tests in endemic settings

Malaria rapid diagnostic tests (RDTs) are instrument-free tests that provide results within 20 min and can be used by community health workers. RDTs detect antigens produced by the Plasmodium parasite such as Plasmodium falciparum histidine-rich protein-2 (PfHPR2) and Plasmodium lactate dehydrogenase (pLDH). The accuracy of RDTs for the diagnosis of uncomplicated P. falciparum infection is equal or superior to routine microscopy (but inferior to expert microscopy). Sensitivity for Plasmodium vivax is 75-100%; for Plasmodium ovale and Plasmodium malariae, diagnostic performance is poor. Design limitations of RDTs include poor sensitivity at low parasite densities, susceptibility to the prozone effect (PfHRP2-detecting RDTs), false-negative results due to PfHRP2 deficiency in the case of pfhrp2 gene deletions (PfHRP2-detecting RDTs), cross-reactions between Plasmodium antigens and detection antibodies, false-positive results by other infections and susceptibility to heat and humidity. End-user's errors relate to safety, procedure (delayed reading, incorrect sample and buffer volumes) and interpretation (not recognizing invalid test results, disregarding faint test lines). Withholding antimalarial treatment in the case of negative RDT results tends to be infrequent and tendencies towards over-prescription of antibiotics have been noted. Numerous shortcomings in RDT kits' labelling, instructions for use (correctness and readability) and contents have been observed. The World Health Organization and partners actively address quality assurance of RDTs by comparative testing of RDTs, inspections of manufacturing sites, lot testing and training tools but no formal external quality assessment programme of end-user performance exists. Elimination of malaria requires RDTs with lower detection limits, for which nucleic acid amplification tests are under development.

Treatment practices in patients with suspected malaria in Provincial Hospital of Tete, Mozambique

BACKGROUND

Nowadays, parasite-based diagnosis by microscopy or malaria rapid diagnostic tests (RDT) is universally promoted before malaria treatment. However, studies on adherence of primary caregivers to malaria test results have provided conflicting results.

METHODS

The antimalarial and antibiotic prescription rates in patients with suspected malaria at Provincial Hospital of Tete, Mozambique, and the features associated with antibiotic prescription in non-severely ill parasite-negative patients were assessed.

RESULTS

In March and April 2010, Plasmodium falciparum malaria was diagnosed by microscopy or RDT in 728 (27.2%) of 2672 patients tested. Almost all malaria patients were prescribed antimalarials and 20% were also given antibiotics. Of 1944 parasite-negative patients, 126 (6.5%) were prescribed antimalarials and 1213 (62.4%) antibiotics. Among non-severely ill parasite-negative patients with complete information (n = 1607), the antibiotic prescription rate was 68.8% and was more frequent with respiratory symptoms and leukocyte counts >10 000/μL (adjusted OR = 1.62, 95% CI 1.18-2.23 and adjusted OR = 2.12, 95% CI 1.66-2.71, respectively).

CONCLUSIONS

Adherence to malaria test results was good in this reference setting, but antibiotic prescription was relatively frequent in clinically stable non-malaria patients. Optimal management of parasite-negative patients must be further defined along with programmatic deployment of the parasite-based strategy.

Abstract P4-08-04: Abcc10 status affects proliferation, metastases and tumor sensitivity

Background: It has been proposed that therapy-induced overexpression of ATP-binding cassette (ABC) drug efflux pumps promotes resistance in many drug-treated cancers. While early studies focused on overexpression and activity of the P-glycoprotein (Pgp) pump, a structurally distinct group of ABC efflux pumps, known as the Multidrug Resistance Proteins (MRPs;ABCCs), have been gaining increasing attention as alternative sources of resistance. There are 9 ABCC family members (ABCC1-6, 10–12), and we have previously shown that ABCC10 is unique because it confers resistance to a wide variety of anticancer agents including taxanes, vinca alkaloids and nucleoside-based analogs (Hopper-Borge et al, 2004, Hopper-Borge et al, 2009). Importantly we have shown that Abcc10 null mice are sensitized to taxanes (Hopper-Borge et al, Cancer Research, 2011). This is the first transporter whose loss results in in vivo tissue sensitivity to taxanes.

Methods & Results: We recently bred a PyVmT mammary tumor model to our Abcc10 gene disrupted mice to investigate Abcc10's in vivo activities regarding breast cancer resistance mechanisms. We have observed that Abcc10+/+ (WT) status limits the rate of tumorigenesis (p = 0.020) and that WT tumors are more metastatic compared to Abcc10−/− (KO), (p = 0.0489). To better understand the potential resistance mechanisms in this model we determined the expression levels of relevant transporters with qRT-PCR and found no significant differences between WT and KO. The PI3K-AKT-mTOR, a major signaling pathway involved in breast cancer progression has been connected to ABCCs (Tazzari, et al, 2007), and we observed upregulation of AKT in KO versus WT mammary tumor cell lines via western analyses. Therefore, we decided to ask if Abcc10 status affects proliferation, attachment, and/or migration (CyQuant, Invitrogen and xCELLigence, Roche). We showed that WT cell lines grow 3 times slower compared to KO. For migration kinetic we observed that KO cell lines were more active compared to WT.

To determine the impact of Abcc10 loss in vivo we injected SCID mice with 3 WT or KO mammary tumor derived cell lines and treated tumors with docetaxel or vehicle. Tumors derived from WT and KO mice were both responsive to docetaxel (WT, p = 0.003 and KO, p = 0.001). However, over 21 days, the WT tumors were reduced by 50% compared to KO reduction of 86%. Kaplan-Meier survival analysis of treated/untreated SCID mice reveals that Abcc10 status is related to a poorer prognosis (KO p &lt; 0.0001, WT p = 0.0648).

Conclusion: Here we show that Abcc10 status limits tumorigenesis (proliferation, attachment, migration) of MMTV-PyVmT mammary tumor model and Abcc10+/+ tumors are more metastatic compared to KO tumors. Thus Abcc10 may be involved in breast cancer development and progression. mRNA expression analysis of ABC transporters in mammary tumors derived cell lines reveals that other transporters do not compensate for Abcc10 loss. In vivo experiments show that treatment with docetaxel is more effective for KO tumors compared to WT tumors, suggesting Abcc10 is a breast cancer resistance factor.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-08-04.

Occurrence of moisture problems in schools in three countries from different climatic regions of Europe based on questionnaires and building inspections - the HITEA study

The aim of this study was to assess occurrence of dampness and mold in school buildings in three European countries (the Netherlands, Spain, and Finland), representing different climatic regions. An assessment was performed utilizing both questionnaires and on-site building investigations, and the agreement between these two methods was evaluated for validation purposes. On the basis of questionnaire data from a representative sample of schools, different types of moisture problems were reported in 24-47% of all school buildings at the time of the study. Most commonly reported was dampness in the Netherlands, moisture/water damage in Spain, and mold odor in Finland. Subsequently, 20-24 schools per country were selected for on-site inspections by trained staff. The overall agreement between the questionnaire and inspection data was good (kappa-value 0.62), however, with large differences (0.39-0.91) between countries. Extrapolating from the inspection data, the minimum estimates for prevalence of moisture problems in school buildings are 20% in the Netherlands, 41% in Spain, and 24% in Finland. In conclusion, moisture problems (such as moisture damage, dampness, and mold) are relatively common in schools. The occurrence and severity may vary across geographical areas, which can be partly explained by building characteristics.

PRACTICAL IMPLICATIONS

On the basis of this study, the prevalence of verified moisture problems in school buildings was highest in Spain, but lower and similar in Finland and the Netherlands. Questionnaire-based surveys can be used to assess moisture problems in school buildings, but because of large variation in agreement with inspection data, the questionnaire needs to be validated by on-site inspections in a subsample of the surveyed buildings.

Long-term outcome of children with acute cerebellitis

BACKGROUND

Acute cerebellitis (AC) is characterized by cerebellar symptoms and magnetic resonance imaging (MRI) changes primarily confined to the cerebellum.

OBJECTIVE

To analyze the neurological and cognitive long-term outcome of children with AC.

METHODS

Children with AC diagnosed by typical clinical features and MRI findings were included in this retrospective study. Medical charts were reviewed and neurological deficits were assessed by neurological examination or by the expanded disability status scale telephone interview. Cognitive outcome was evaluated with a parental questionnaire (Kognitive Probleme bei Kindern und Jugendlichen).

RESULTS

A total of 11 children (6 boys, 5 girls; age range: 3 years to 14 years and 10 months) were included. Of them, six children had a severe disease manifestation including mental status changes and neurological symptoms. Of the rest, two children had a moderate and three children had a mild form of AC. MRI of the cerebellum was obtained in the acute phase revealing signal alterations with different patterns. The average follow-up period was 4 years and 4 months. A complete recovery was observed in five children. Neurological sequelae were reported in five children ranging from ataxia to mild tremor. Cognitive deficits were found in six patients. The affected areas of cognition did include spatial visualization ability, language skills, and concentration.

CONCLUSION

Neurological and cognitive sequelae are common in children with AC and underline the role of the cerebellum in cognition.

High-frequency oscillations (HFOs) in clinical epilepsy

Epilepsy is one of the most frequent neurological diseases. In focal medically refractory epilepsies, successful surgical treatment largely depends on the identification of epileptogenic zone. High-frequency oscillations (HFOs) between 80 and 500Hz, which can be recorded with EEG, may be novel markers of the epileptogenic zone. This review discusses the clinical importance of HFOs as markers of epileptogenicity and their application in different types of epilepsies. HFOs are clearly linked to the seizure onset zone, and the surgical removal of regions generating them correlates with a seizure free post-surgical outcome. Moreover, HFOs reflect the seizure-generating capability of the underlying tissue, since they are more frequent after the reduction of antiepileptic drugs. They can be successfully used in pediatric epilepsies such as epileptic spasms and help to understand the generation of this specific type of seizures. While mostly recorded on intracranial EEGs, new studies suggest that identification of HFOs on scalp EEG or magnetoencephalography (MEG) is possible as well. Thus not only patients with refractory epilepsies and invasive recordings but all patients might profit from the analysis of HFOs. Despite these promising results, the analysis of HFOs is not a routine clinical procedure; most results are derived from relatively small cohorts of patients and many aspects are not yet fully understood. Thus the review concludes that even if HFOs are promising biomarkers of epileptic tissue, there are still uncertainties about mechanisms of generation, methods of analysis, and clinical applicability. Large multicenter prospective studies are needed prior to widespread clinical application.

Comparison of visual grading and free-response ROC analyses for assessment of image-processing algorithms in digital mammography

OBJECTIVE

To compare two methods for assessment of image-processing algorithms in digital mammography: free-response receiver operating characteristic (FROC) for the specific task of microcalcification detection and visual grading analysis (VGA).

METHODS

The FROC study was conducted prior to the VGA study reported here. 200 raw data files of low breast density (Breast Imaging-Reporting and Data System I-II) mammograms (Novation DR, Siemens, Germany)-100 of which abnormal-were processed by four image-processing algorithms: Raffaello (IMS, Bologna, Italy), Sigmoid (Sectra, Linköping, Sweden), and OpView v. 2 and v. 1 (Siemens, Erlangen, Germany). Four radiologists assessed the mammograms for the detection of microcalcifications. 8 months after the FROC study, a subset (200) of the 800 images was reinterpreted by the same radiologists, using the VGA methodology in a side-by-side approach. The VGA grading was based on noise, saturation, contrast, sharpness and confidence with the image in terms of normal structures. Ordinal logistic regression was applied; OpView v. 1 was the reference processing algorithm.

RESULTS

In the FROC study all algorithms performed better than OpView v. 1. From the current VGA study and for confidence with the image, Sigmoid and Raffaello were significantly worse (p<0.001) than OpView v. 1; OpView v. 2 was significantly better (p=0.01). For the image quality criteria, results were mixed; Raffaello and Sigmoid for example were better than OpView v. 1 for sharpness and contrast (although not always significantly).

CONCLUSION

VGA and FROC discordant results should be attributed to the different clinical task addressed.

ADVANCES IN KNOWLEDGE

The method to use for image-processing assessment depends on the clinical task tested.

Presence of extended-spectrum beta-lactamase-producing Enterobacteriaceae in waste waters, Kinshasa, the Democratic Republic of the Congo

Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae are a major public health concern. We previously demonstrated the presence of ESBL-producing Enterobacteriaceae in sachet-packaged water bags sold in Kinshasa, the Democratic Republic of the Congo. In complement to the previous study, we aimed to assess the presence of ESBL-producing Enterobacteriaceae in waste waters in Kinshasa.Enterobacteriaceae isolates recovered from environmental water samples were screened and phenotypically confirmed as ESBL-producers by disk diffusion according to Clinical and Laboratory Standards Institute (CLSI) guidelines (CLSI M100-S21). Final identification to the species level and further antimicrobial susceptibility testing were carried out with MicroScan® NBC42 panels and the identification of bla (ESBL) coding genes was performed by a commercial multiplex ligation polymerase chain reaction (PCR) microarray (Check-Points CT 101, Wageningen, the Netherlands). Overall, 194 non-duplicate Enterobacteriaceae were recovered from several sewer and river sites in nine out of 24 municipalities of Kinshasa. Fourteen isolates (7.4 %) were confirmed as ESBL-producers, the main species being Enterobacter cloacae (46.6 %) and Klebsiella pneumoniae (40.0 %). Associated resistance to both aminoglycoside and fluoroquinolone antibiotics was observed in ten isolates; the remaining isolates showed co-resistance to either fluoroquinolone (n = 3) or to aminoglycoside (n = 1) alone. All but one isolate carried bla (CTX-M) genes belonging to the CTX-M-1 group. ESBL-producing Enterobacteriaceae are increasingly being reported from various sources in the community. The present results suggest that ESBL-producing Enterobacteriaceae are widespread in the environment in the community of Kinshasa. Cities in Central Africa should be added to the map of potentially ESBL-contaminated environments and highlight the need to reinforce safe water supply and public sanitation.