Functional analysis of postural spinal and pelvic parameters using static and dynamic spinometry.

Background: Spinometry is a radiation-free method to three-dimensional spine imaging that provides additional information about the functional gait patterns related to the pelvis and lower extremities. This radiation-free technology uses the surface topography of the trunk to analyze surface asymmetry and identify bony landmarks, thereby aiding the assessment of spinal deformity and supporting long-term treatment regimes. Especially reliable dynamic spinometric data for spine and pelvis are necessary to evaluate the management of non-specific back pain. Research aim: This study aims to generate reliable dynamic spinometric data for spine and pelvis parameters that can serve as reference data for future studies and clinical practice. Methods: This study assessed 366 subjects (185 females) under static and 360 subjects (181 females) under dynamic (walking on a treadmill at 3 km/h and 5 km/h) conditions. The DIERS Formetric 4Dmotion® system uses stripes of light to detect the surface topography of the spine and pelvis and identifies specific landmarks to analyze the spine during standing and walking. Results: Relevant gender effects were calculated for lordotic angle (ηp2 = 0.22) and pelvic inclination (ηp2 = 0.26). Under static conditions, female subjects showed larger values for both parameters (lordotic angle: 41.6 ± 8.60°; pelvic inclination: 25.5 ± 7.49°). Regarding speed effects, three relevant changes were observed (sagittal imbalance: ηp2 = 0.74, kyphotic angle: ηp2 = 0.13, apical deviation: ηp2 = 0.11). The most considerable changes were observed between static condition and 3 km/h, especially for sagittal imbalance and lordotic angle. For these parameters, relevant effect sizes (d > 0.8) were calculated between static and 3 km/h for males and females. Concerning clinical vertebral parameters, only lordotic angle and pelvic inclination were correlated with each other (r = 0.722). Conclusion: This study generated a gender-specific reference database of asymptomatic individuals for static and dynamic spinometry. It demonstrated that the DIERS Formetric 4Dmotion® system could capture natural changes in static and dynamic situations and catalogue functional adaptations of spino-pelvic statics at different speeds. The lordotic angle is an indirect marker of pelvic inclination, allowing spinometry to identify individuals at risk even under dynamic conditions.

Arm Ergometry to Improve Mobility in Progressive Multiple Sclerosis (AMBOS)-Results of a Pilot Randomized Controlled Trial.

Background: Walking disability is one of the most frequent and burdening symptoms of progressive multiple sclerosis (MS). Most of the exercise intervention studies that showed an improvement in mobility performance were conducted in low to moderately disabled relapsing-remitting MS patients with interventions using the legs. However, MS patients with substantial walking disability hardly can perform these tasks. Earlier work has indicated that aerobic arm training might also improve walking performance and could therefore be a therapeutic option in already moderately disabled progressive MS patients. Methods: Patients with progressive MS and EDSS 4-6.5 were randomized using a computer-generated algorithm list to either a waitlist control group (CG) or an intervention group (IG). The IG performed a 12-week home-based, individualized arm ergometry exercise training program. Maximum walking distance as measured by the 6-min walking test (6MWT) was the primary endpoint. Secondary endpoints included aerobic fitness, other mobility tests, cognitive functioning, as well as fatigue and depression. Results: Of n = 86 screened patients, 53 with moderate disability (mean EDSS 5.5, SD 0.9) were included and data of 39 patients were analyzed. Patients in the IG showed strong adherence to the program with a mean of 67 (SD 26.4) training sessions. Maximum work load (P max) increased in the training group while other fitness indicators did not. Walking distance in the 6MWT improved in both training and waitlist group but not significantly more in trained patients. Similarly, other mobility measures showed no differential group effect. Cognitive functioning remained unchanged. No serious events attributable to the intervention occurred. Conclusion: Although maximum work load improved, 3 months of high-frequency arm ergometry training of low to moderate intensity could not show improved walking ability or cognitive functioning in progressive MS compared to a waitlist CG. The study was registered at www.clinicaltrials.gov (NCT03147105) and funded by the local MS self-help organization.

Dynamic contrast-enhanced magnetic resonance imaging for monitoring neovascularization during bone regeneration-a randomized in vivo study in rabbits.

OBJECTIVES: Micro-computed tomography (µ-CT) and histology, the current gold standard methods for assessing the formation of new bone and blood vessels, are invasive and/or destructive. With that in mind, a more conservative tool, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), was tested for its accuracy and reproducibility in monitoring neovascularization during bone regeneration. Additionally, the suitability of blood perfusion as a surrogate of the efficacy of osteoplastic materials was evaluated. MATERIALS AND METHODS: Sixteen rabbits were used and equally divided into four groups, according to the time of euthanasia (2, 3, 4, and 6 weeks after surgery). The animals were submitted to two 8-mm craniotomies that were filled with blood or autogenous bone. Neovascularization was assessed in vivo through DCE-MRI, and bone regeneration, ex vivo, through µ-CT and histology. RESULTS: The defects could be consistently identified, and their blood perfusion measured through DCE-MRI, there being statistically significant differences within the blood clot group between 3 and 6 weeks (p = 0.029), and between the former and autogenous bone at six weeks (p = 0.017). Nonetheless, no significant correlations between DCE-MRI findings on neovascularization and µ-CT (r =-0.101, 95% CI [-0.445; 0.268]) or histology (r = 0.305, 95% CI [-0.133; 0.644]) findings on bone regeneration were observed. CONCLUSIONS: These results support the hypothesis that DCE-MRI can be used to monitor neovascularization but contradict the premise that it could predict bone regeneration as well.

Increased myocardial mass and attenuation of myocardial strain in professional male soccer players and competitive male triathletes.

The purpose of this prospective study was to analyze the relationship between ventricular morphology and parameters of cardiac function in two different athletic groups and controls, using feature tracking cardiac magnetic resonance (FT-CMR). Twenty-three professional soccer players (22 ± 4 years), 19 competitive triathletes (28 ± 6 years) and 16 controls (26 ± 3 years) were included in the study. CMR was performed using a 1.5 T scanner. Cardiac chamber volumes, mass and biventricular global myocardial strain were obtained and compared. In comparison to the control subjects, athletes were characterized by a higher cardiac volume (p < 0.0001), higher cardiac mass (p < 0.001), reduced longitudinal strain of the left and right ventricle (p < 0.05 and p < 0.01 respectively) and reduced left ventricular radial strain (p < 0.05). Soccer players revealed higher amounts of left ventricular mass (87 ± 15 vs. 75 ± 13 g/m2, p < 0.05) than triathletes. Moreover, they showed a greater decrease in left and right ventricular longitudinal strain (p < 0.05 and p < 0.05) as well as in radial left ventricular strain (p < 0.05) in comparison to triathletes. An increase in left ventricular mass correlated significantly with a decrease in longitudinal (r = 0.47, p < 0.001) and radial (r = - 0.28, p < 0.05) strain. In athletes, attenuation of strain values is associated with cardiac hypertrophy and differ between soccer players and triathletes. Further studies are needed to investigate whether it is an adaptive or maladaptive change of the heart induced by intense athletic training.

Case series on acute HCV in HIV-negative men in regular clinical practice: a call for action.

BACKGROUND: The evidence that HIV treatment as prevention (TasP) and HIV pre-exposure prophylaxis (PrEP) reduces the risk of HIV transmission is overwhelming. But as PrEP and TasP can lead to increased sexual mixing between HIV positive and negative men who have sex with men (MSM), sexually transmitted infections such as acute hepatitis C (HCV), which were thought to be limited to HIV-infected MSM, could become more frequent in HIV uninfected MSM as well. The objective of this study was to describe a series of cases of sexually transmitted HCV infections in HIV-uninfected MSM in the Netherlands and Belgium. METHODS: Through the Dutch Acute HCV in HIV Study (a Dutch-Belgian prospective multicentre study on the treatment of acute HCV infection, NCT02600325) and the Be-PrEP-ared study (a PrEP project in Antwerp, EudraCT2015-000054-37) several acute HCV infections were detected in HIV-negative men. RESULTS: A newly acquired HCV infection was diagnosed in ten HIV-negative MSM. HCV was diagnosed at a sexually transmitted infection (STI) clinic (n = 2), by their general practitioner (n = 2), by their HIV physician (n = 1) or at a PrEP clinic (n = 5). Ten patients reported unprotected anal intercourse and four had a concomitant STI at the time of HCV diagnosis. Six patients reported using drugs during sex. CONCLUSIONS: Our observation calls for a larger nationwide epidemiological study on the prevalence, incidence and risk factors of HCV infection in HIV-uninfected MSM. In the changing landscape of TasP and PrEP, reliable and up-to-date epidemiological data on HCV among HIV-uninfected MSM are needed and will help in developing evidence-based testing policies.

Magnetic Resonance Imaging Score and Classification System (AMADEUS) for Assessment of Preoperative Cartilage Defect Severity.

Objective To design a simple magnetic resonance (MR)-based assessment system for quantification of osteochondral defect severity prior to cartilage repair surgery at the knee. Design The new scoring tool was supposed to include 3 different parameters: (1) cartilage defect size, (2) depth/morphology of the cartilage defect, and (3) subchondral bone quality, resulting in a specific 3-digit code. A clearly defined numeric score was developed, resulting in a final score of 0 to 100. Defect severity grades I through IV were defined. For intra- and interobserver agreement, defects were assessed by 2 independent readers on preoperative knee MR images of n = 44 subjects who subsequently received cartilage repair surgery. For statistical analyses, mean values ± standard deviation (SD), interclass correlation coefficients (ICC), and linear weighted kappa values were calculated. Results The mean total Area Measurement And DEpth & Underlying Structures (AMADEUS) score was 48 ± 24, (range, 0-85). The mean defect size was 2.8 ± 2.6 cm2. There were 36 of 44 full-thickness defects. The subchondral bone showed defects in 21 of 44 cases. Kappa values for intraobserver reliability ranged between 0.82 and 0.94. Kappa values for interobserver reliability ranged between 0.38 and 0.85. Kappa values for AMADEUS grade were 0.75 and 0.67 for intra- and interobserver agreement, respectively. ICC scores for the AMADEUS total score were 0.97 and 0.96 for intra- and interobserver agreement, respectively. Conclusions The AMADEUS score and classification system allows reliable severity encoding, scoring and grading of osteochondral defects on knee MR images, which is easily clinically applicable in daily practice.

T2* Mapping for Hip Joint Cartilage Assessment: Pre-MRI Exercise and Time of Imaging Do Not Bias the T2* Measurement in Asymptomatic Volunteers.

Objective To identify if the time of day and pre-imaging exercise matter while performing T2* mapping of hip joint cartilage at 3 T. Design Nine asymptomatic healthy volunteers (mean age 27.4 ± 4.0 years) with no obvious morphological evidence of cartilage damage were enrolled. The MRI protocol included a double-echo steady state (DESS) sequence for morphological cartilage assessment and a multi-echo data image combination sequence for the T2* measurement. T2* values were obtained between 8 and 11 a.m., between 3 and 6 p.m., and after 50 knee-bends at several time points of each measurement (0, 15, 30, 45, 60 minutes). Results We observed no differences ( P = 0.47) between the T2* values obtained in the morning (T2* = 22.9 ± 3.0 ms) and those measured in the afternoon (T2* = 23.2 ± 3.2 ms). We also observed no statistically significant differences between the T2* values at different time points ( P = 0.67) or after 50 knee-bends ( P = 0.43). Conclusions Timing of the scan and pre-imaging exercise clearly did not matter in this modality. This study consolidates the value of T2* imaging in hip joint cartilage that seems to be independent of diurnal effects and physical activity prior to MRI.

The Netherlands Chlamydia cohort study (NECCST) protocol to assess the risk of late complications following Chlamydia trachomatis infection in women.

BACKGROUND: Chlamydia trachomatis (CT), the most common bacterial sexually transmitted infection (STI) among young women, can result in serious sequelae. Although the course of infection is often asymptomatic, CT may cause pelvic inflammatory disease (PID), leading to severe complications, such as prolonged time to pregnancy, ectopic pregnancy, and tubal factor subfertility. The risk of and risk factors for complications following CT-infection have not been assessed in a long-term prospective cohort study, the preferred design to define infections and complications adequately. METHODS: In the Netherlands Chlamydia Cohort Study (NECCST), a cohort of women of reproductive age with and without a history of CT-infection is followed over a minimum of ten years to investigate (CT-related) reproductive tract complications. This study is a follow-up of the Chlamydia Screening Implementation (CSI) study, executed between 2008 and 2011 in the Netherlands. For NECCST, female CSI participants who consented to be approached for follow-up studies (n = 14,685) are invited, and prospectively followed until 2022. Four data collection moments are foreseen every two consecutive years. Questionnaire data and blood samples for CT-Immunoglobulin G (IgG) measurement are obtained as well as host DNA to determine specific genetic biomarkers related to susceptibility and severity of infection. CT-history will be based on CSI test outcomes, self-reported infections and CT-IgG presence. Information on (time to) pregnancies and the potential long-term complications (i.e. PID, ectopic pregnancy and (tubal factor) subfertility), will be acquired by questionnaires. Reported subfertility will be verified in medical registers. Occurrence of these late complications and prolonged time to pregnancy, as a proxy for reduced fertility due to a previous CT-infection, or other risk factors, will be investigated using longitudinal statistical procedures. DISCUSSION: In the proposed study, the occurrence of late complications following CT-infection and its risk factors will be assessed. Ultimately, provided reliable risk factors and/or markers can be identified for such late complications. This will contribute to the development of a prognostic tool to estimate the risk of CT-related complications at an early time point, enabling targeted prevention and care towards women at risk for late complications. TRIAL REGISTRATION: Dutch Trial Register NTR-5597 . Retrospectively registered 14 February 2016.

Does T2 mapping of the posterior annulus fibrosus indicate the presence of lumbar intervertebral disc herniation? A 3.0 Tesla magnetic resonance study.

PURPOSE: Indicating lumbar disc herniation via magnetic resonance imaging (MRI) T2 mapping in the posterior annulus fibrosus (AF). METHODS: Sagittal T2 maps of 313 lumbar discs of 64 patients with low back pain were acquired at 3.0 Tesla (3T). The discs were rated according to disc herniation and bulging. Region of interest (ROI) analysis was performed on median, sagittal T2 maps. T2 values of the AF, in the most posterior 10% (PAF-10) and 20% of the disc (PAF-20), were compared. RESULTS: A significant increase in the T2 values of discs with herniations affecting the imaged area, compared to bulging discs and discs with lateral herniation, was shown in the PAF-10, where no association to the NP was apparent. The PAF-20 exhibited a moderate correlation to the nucleus pulposus (NP). CONCLUSIONS: High T2 values in the PAF-10 suggest the presence of disc herniation (DH). The results indicate that T2 values in the PAF-20 correspond more to changes in the NP.

Ethnic and regional differences in STI clinic use: a Dutch epidemiological study using aggregated STI clinic data combined with population numbers.

OBJECTIVES: Ethnic minorities (EM) from STI-endemic countries are at increased risk to acquire an STI. The objectives of this study were to investigate the difference in STI clinic consultation and positivity rates between ethnic groups, and compare findings between Dutch cities. METHODS: Aggregated population numbers from 2011 to 2013 of 15-44 year-old citizens of Amsterdam, Rotterdam, The Hague and Utrecht extracted from the population register (N=3 129 941 person-years) were combined with aggregated STI clinic consultation data in these cities from the national STI surveillance database (N=113 536). Using negative binomial regression analyses (adjusted for age and gender), we compared STI consultation and positivity rates between ethnic groups and cities. RESULTS: Compared with ethnic Dutch (consultation rate: 40.3/1000 person-years), EM from Eastern Europe, Sub-Sahara Africa, Suriname, the Netherlands Antilles/Aruba and Latin America had higher consultation rates (range relative risk (RR): 1.27-2.26), whereas EM from Turkey, North Africa, Asia and Western countries had lower consultation rates (range RR: 0.29-0.82). Of the consultations among ethnic Dutch, 12.2% was STI positive. Positivity rates were higher among all EM groups (range RR: 1.14-1.81). Consultation rates were highest in Amsterdam and lowest in Utrecht independent of ethnic background (range RR Amsterdam vs Utrecht: 4.30-10.30). Positivity rates differed less between cities. CONCLUSIONS: There were substantial differences in STI clinic use between ethnic groups and cities in the Netherlands. Although higher positivity rates among EM suggest that these high-risk individuals reach STI clinics, it remains unknown whether their reach is optimal. Special attention should be given to EM with comparatively low consultation rates.

Delayed linkage to care in one-third of HIV-positive individuals in the Netherlands.

OBJECTIVES: To determine time to linkage to HIV care following diagnosis and to identify risk factors for delayed linkage. METHODS: Patients newly diagnosed with HIV at sexually transmitted infections (STI) clinics in the Netherlands were followed until linkage to care. Data were collected at the time of diagnosis and at first consultation in care, including demographics, behavioural information, CD4+ counts and HIV viral load (VL) measurements. Delayed linkage to care was defined as >4 weeks between HIV diagnosis and first consultation. RESULTS: 310 participants were included; the majority (90%) being men who have sex with men (MSM). For 259 participants (84%), a date of first consultation in care was known; median time to linkage was 9 days (range 0-435). Overall, 95 (31%) of the participants were not linked within 4 weeks of diagnosis; among them, 44 were linked late, and 51 were not linked at all by the end of study follow-up. Being young (<25 years), having non-Western ethnicity or lacking health insurance were independently associated with delayed linkage to care as well as being referred to care indirectly. Baseline CD4+ count, VL, perceived social support and stigma at diagnosis were not associated with delayed linkage. Risk behaviour and CD4+ counts declined between diagnosis and linkage to care. CONCLUSIONS: Although most newly diagnosed patients with HIV were linked to care within 4 weeks, delay was observed for one-third, with over half of them not yet linked at the end of follow-up. Vulnerable subpopulations (young, uninsured, ethnic minority) were at risk for delayed linkage. Testing those at risk is not sufficient, timely linkage to care needs to be better assured as well.

Limited integrative repair capacity of native cartilage autografts within cartilage defects in a sheep model.

The purpose of this study was to investigate integration and cellular outgrowth of native cartilage autografts transplanted into articular cartilage defects. Native cartilage autografts were applied into chondral defects in the femoral condyle of adult sheep. Within the defects, the calcified cartilage layer was either left intact or perforated to induce bone marrow stimulation. Empty defects served as controls. The joints were analyzed after 6 and 26 weeks by macroscopic and histological analysis using the ICRS II Score and Modified O'Driscoll Scores. Non-treated defects did not show any endogenous regenerative response and bone marrow stimulation induced fibrous repair tissue. Transplanted native cartilage grafts only insufficiently integrated with the defect borders. Cell death and loss of proteoglycans were present at the margins of the grafts at 6 weeks, which was only partially restored at 26 weeks. Significant cellular outgrowth from the grafts or defect borders could not be observed. Bonding of the grafts could be improved by additional bone marrow stimulation providing ingrowing cells that formed a fibrous interface predominantly composed of type I collagen. Transplanted native cartilage grafts remain as inert structures within cartilage defects and fail to induce integrative cartilage repair which rather demands additional cells provided by additional bone marrow stimulation.

T2* mapping for articular cartilage assessment: principles, current applications, and future prospects.

With advances in joint preservation surgery that are intended to alter the course of osteoarthritis by early intervention, accurate and reliable assessment of the cartilage status is critical. Biochemically sensitive MRI techniques can add robust biomarkers for disease onset and progression, and therefore, could be meaningful assessment tools for the diagnosis and follow-up of cartilage abnormalities. T2* mapping could be a good alternative because it would combine the benefits of biochemical cartilage evaluation with remarkable features including short imaging time and the ability of high-resolution three-dimensional cartilage evaluation-without the need for contrast media administration or special hardware. Several in vitro and in vivo studies, which have elaborated on the potential of cartilage T2* assessment in various cartilage disease patterns and grades of degeneration, have been reported. However, much remains to be understood and certain unresolved questions have become apparent with these studies that are crucial to the further application of this technique. This review summarizes the principles of the technique and current applications of T2* mapping for articular cartilage assessment. Limitations of recent studies are discussed and the potential implications for patient care are presented.

The anatomy of non-carious cervical lesions.

OBJECTIVE: The term "non-carious cervical lesion" (NCCL) describes a dental hard tissue defect of unknown origin. Two very distinct variations are known: wedge-shaped and saucer-shaped lesions. Reasons for occurrence of two forms might include different contributing factors. METHODS: Forty-two teeth, 19 wedge-shaped and 23 saucer-shaped lesions, were analysed by light and confocal laser scanning microscopy (CLSM) to investigate presence of calculus and organic matter, surface structure of the lesion, borders of the lesion, and potential fractures in the dental hard tissues. RESULTS: One hundred percent of the wedge-shaped teeth showed evidence of additional abrasion (incisal/occlusal surface) but only 70% of the saucer-shaped teeth. In most teeth, the edge was rounded. Tiny grooves parallel to the cemento-enamel junction (CEJ) were present in 11% of the wedge-shaped and in 39% of the saucer-shaped lesions. Seventy-nine percent wedge-shaped and 52% saucer-shaped lesions had some sort of apposition. Eighty-eight percent of all teeth had dead tracts, 62% of which were located directly next to the defect (in the lesion). In 48%, sclerotic dentin was present right next to the defect (in the lesion). Tertiary dentin was visible in 60%. Not a single fracture was detected. CONCLUSION: Different characteristics associated with each type of cervical lesion support the theory of different aetiology or at least of differing contributions from different factors that participate in the development of NCCLs. CLINICAL RELEVANCE: Only knowledge of the correct aetiology of NCCLs will allow the best treatment and prevention for such lesions.

Osteitis and synovitis, but not bone erosion, is associated with proteoglycan loss and microstructure damage in the cartilage of patients with rheumatoid arthritis.

OBJECTIVES: To investigate the relation between anatomic changes of the synovium, the bone, the bone marrow and the cartilage to biochemical properties of the cartilage in patients with rheumatoid arthritis (RA). METHODS: 33 patients with RA received 3-T MRI scans of the metacarpophalangeal joints. Two independent methods, (A) the delayed gadolinium enhanced MRI of the cartilage (dGEMRIC, T2-mapping), which was used to assess the biochemical properties of the cartilage; (B) synovitis, osteitis and bone erosions were quantified according to the RA MRI scoring (RAMRIS) method and cartilage thickness (CT), interbone joint space (IBJS, distance between proximal and distal bone surface) and intercartilage joint space (ICJS, distance between proximal and distal cartilage surface) were measured. RESULTS: Biochemical changes of the cartilage, corresponding to low dGEMRIC and high T2 values, were more likely to be seen in joints with decreased IBJS and ICJS as well as decreased CT. For instance, dGEMRIC was directly correlated to the IBJS (p=0.001) and ICJS (p=0.001), whereas T2 mapping was inversely correlated to IBJS and ICJS (both p=0.017). Moreover, the degree of osteitis, and to some extent synovitis, was correlated to biochemical cartilage changes as measured by dGEMRIC (p=0.003) or the T2 mapping (p=0.013). By contrast, bone erosions did not correlate to the degree of biochemical cartilage changes. DISCUSSION: These data support the concept that synovitis and osteitis may be two main triggers for cartilage damage. Thus, the actual inflammatory state of a joint, but not so much the degree of bone erosion, appears to influence cartilage properties in RA.

Lymphogranuloma venereum among men who have sex with men in the Netherlands: regional differences in testing rates lead to underestimation of the incidence, 2006-2012.

Since 2003, an epidemic of lymphogranuloma venereum (LGV) has been ongoing in men who have sex with men (MSM) in Europe. Of 92,271 MSM consulting sexually transmitted disease (STI) clinics in the Netherlands between 2006 and 2011, 63,228 (68%) were tested for anorectal Chlamydia infection, with 6,343 (10%) positive diagnoses. In 4,776 of those (75%), LGV testing was performed, with regional variation from 7% to 97%. In total 414 LGV cases were diagnosed, a mean annual positivity rate of 8.7%, decreasing from 14% in 2007 to 6% in 2011, but increasing to 13.1% during 2012 (184 new cases). Risk factors for LGV were human immunodeficiency virus (HIV) positivity (odds ratio (OR)=4.1; 95% confidence interval (CI): 3.2­5.3), STI symptoms (OR=4.1; 95% CI: 3.1­5.4), more than 50 sex partners in the past six months (OR=3.7; 95% CI: 1.1­12.4), older age (40­44 years: OR=2.1; 95% CI: 1.5­2.8), no condom use (OR=2.2; 95% CI: 1.2­3.9) and homosexuality (as opposed to bisexuality; OR=2.2; 95% CI: 1.1­4.2). Regional differences in LGV testing rates limit national LGV surveillance, leading to an underestimation of the real incidence. Characteristics of MSM with LGV did not change over time, so existing prevention strategies should be intensified.

Comparing two definitions of ethnicity for identifying young persons at risk for chlamydia.

Ethnic disparities in chlamydia infections in The Netherlands were assessed, in order to compare two definitions of ethnicity: ethnicity based on country of birth and self-defined ethnicity. Chlamydia positivity in persons aged 16-29 years was investigated using data from the first round of the Chlamydia Screening Implementation (CSI, 2008-2009) and surveillance data from STI centres (2009). Logistic regression modelling showed that being an immigrant was associated with chlamydia positivity in both CSI [adjusted odds ratio (aOR) 2·3, 95% confidence interval (CI) 2·0-2·6] and STI centres (aOR 1·4, 95% CI 1·3-1·5). In both settings, 60% of immigrants defined themselves as Dutch. Despite the difference, classification by self-defined ethnicity resulted in similar associations between (non-Dutch) ethnicity and chlamydia positivity. However, ethnicity based on country of birth explained variation in chlamydia positivity better, and is objective and constant over time and therefore more useful for identifying young persons at higher risk for chlamydia infection.

Outbreak investigation in two groups of coach passengers with gastroenteritis returning from Germany to the Netherlands in February 2009.

In February 2009, an outbreak of 38 cases of gastroenteritis occurred among the participants of two Dutch coach trips (A and B) who visited the same hotel in Germany. We initiated an outbreak investigation to determine possible risk of food-borne infection. A retrospective cohort study was performed among 87 passengers using a self-administered questionnaire. The response rate was 75 of 87 (86%). Mean age was 65 years. Cases were defined as participants of the two coach trips who had diarrhoea and/or vomiting at least once within 24 hours in the period between 7 and 14 February 2009. We distinguished early and late cases, with symptoms starting within or after 72 hours of arrival in the hotel. Overall attack-rate was 38 of 75 (51%). Microbiological investigation was performed on stool samples of two passengers from Coach A and two passengers from Coach B. Identical norovirus genotype II.4 sequences were detected in all four samples. Univariate analysis revealed a potential risk for early cases from juice consumption , which was most clearly seen for Coach B on day of arrival (juice at lunch: relative risk (RR): 3.9, 95% confidence interval (CI): 1.3-11.7; juice at dinner: RR: 5.5, 95% CI: 1.6-18.1). A dose-response relationship was found. This outbreak was probably caused by using the taps of juice served in large containers with a tap for self-service, due to environmental contamination through person-to-person transmission. Still the role of either contaminated juice or contact with contaminated juice cannot be ruled out.

Delayed gadolinium-enhanced MRI of cartilage in the ankle at 3 T: feasibility and preliminary results after matrix-associated autologous chondrocyte implantation.

PURPOSE: To demonstrate the feasibility of delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) in the ankle at 3 T and to obtain preliminary data on matrix associated autologous chondrocyte (MACI) repair tissue. MATERIALS AND METHODS: A 3D dual flip angle sequence was used with an eight-channel multipurpose coil at 3 T to obtain T1 maps both pre- and postintravenous contrast agent (Magnevist, 0.2 mM/kg). Postcontrast T1 over time was evaluated in three volunteers; a modified dGEMRIC protocol was then used to assess 10 cases after MACI in the ankle. RESULTS: Forty-five minutes were found sufficient for maximum T1 decrease. MACI cases had a precontrast mean T1 of 1050 +/- 148.4 msec in reference cartilage (RC) and 1080 +/- 165.6 msec in repair tissue (RT). Postcontrast T1 decreased to 590 +/- 134.0 msec in RC and 554 +/- 133.0 msec in RT. There was no significant difference between the delta relaxation rates in RT (9.44 x 10(-4) s(-1)) and RC (8.04 x 10(-4) s(-1), P = 0.487). The mean relative delta relaxation rate was 1.34 +/- 0.83. CONCLUSION: It is feasible to assess the thin cartilage layers of the ankle with dGEMRIC at 3 T; MACI can yield RT with properties similar to articular cartilage.