External validation of six clinical models for prediction of unknown chronic kidney disease in a German population

Background Chronic kidney disease (CKD) is responsible for large personal health and societal burdens. Screening populations at higher risk for CKD is effective to initiate earlier treatment and decelerate disease progress. We externally validated clinical prediction models for unknown CKD that might be used in population screening. Methods We validated six risk models for prediction of unknown CKD using only non-invasive parameters. Validation data came from 4,185 participants of the German Heinz-Nixdorf-Recall study (HNR), drawn in 2000 from a general population aged 45-75 years. We estimated discrimination and calibration using the full model information, and calculated the diagnostic properties applying the published scoring algorithms of the models using various thresholds for the sum of scores. Results The risk models used four to nine parameters. Age and hypertension were included in all models. Five out of six c-values ranged from 0.71 to 0.73, indicating fair discrimination. Positive predictive values ranged from 15% to 19%, negative predictive values were >93% using score thresholds that resulted in values for sensitivity and specificity above 60%. Conclusions Most of the selected CKD prediction models show fair discrimination in a German general population. The estimated diagnostic properties indicate that the models are suitable for identifying persons at higher risk for unknown CKD without invasive procedures.

Symptoms are the Most Effective Child SCAT5 Component for Recognizing Concussion on the Day of Injury

Background: The Child Sport Concussion Assessment Tool 5th Edition (Child SCAT5) was developed to evaluate children between 5-12 years of age for a suspected concussion. However, limited empirical evidence exists demonstrating the value of the Child SCAT5 for acute concussion assessment. Therefore, the purpose of our study was to examine differences and assess the diagnostic properties of Child SCAT5 scores among concussed and non-concussed middle school children on the same day as a suspected concussion.Methods: Our participants included 34 concussed (21 boys, 13 girls; age=12.8±0.86 years) and 44 non-concussed (31 boys, 13 girls; age=12.4±0.76 years) middle school children who were administered the Child SCAT5 upon suspicion of a concussion. Child SCAT5 scores were calculated from the symptom evaluation (total symptoms, total severity), child version of the Standardized Assessment of Concussion (SAC-C), and modified Balance Error Scoring System (mBESS). The Child SCAT5 scores were compared between the concussed and non-concussed groups. Non-parametric effect sizes (r=z/√n) were calculated to assess the magnitude of difference for each comparison. The diagnostic properties (sensitivity, specificity, diagnostic accuracy, predictive values, likelihood ratios, and diagnostic odds ratio) of each Child SCAT5 score were also calculated.Results: Concussed children endorsed more symptoms (p<0.001, r=0.45), higher symptom severity (p<0.001, r=0.44), and had higher double leg (p=0.046, r=0.23), single leg (p=0.035, r=0.24), and total scores (p=0.022, r=0.26) for the mBESS than non-concussed children. No significant differences were observed for the SAC-C scores (p’s≥0.542). The quantity and severity of endorsed symptoms had the best diagnostic accuracy (AUC=0.76–0.77), negative predictive values (NPV=0.84–0.88), and negative likelihood ratios (-LR=0.22–0.31) of the Child SCAT5 scores.Conclusions: The symptom evaluation was the most effective component of the Child SCAT5 for differentiating between concussed and non-concussed middle school children on the same day as a suspected concussion.

Effectiveness of Velscope and Vizilite Plus Systems in Diagnostics of Oral Lesions

Aim: To compare the level of diagnostic coincidence between classical (standard) method and VELscope and ViziLite Plus systems in the diagnosis of different oral lesions. Material and methods: 184 oral lesions were examined using classical method, VELscope and ViziLite Plus systems, and after that underwent a pathohistological examination for diagnosis proof. The percentage of diagnostic coincidence for various types of lesions was analyzed for the three methods compared. Results: The results demonstrated the highest coincidence rate for lesions diagnosed with VELscope – 35 (83.3%), followed by those with classical method – 80 (80.8%), and those with the application of ViziLite – 33 (76.7%). In premalignant and malignant lesions, the highest percentage of diagnostic coincidence was reported using the classical method – 14 (93.3%), for non-malignant lesions using VELscope – 28 (84.8%), for inflammatory and reactive lesions using VELscope – 14 (82.4%) and for lesions associated with general disease and systemic medication again using VELscope – 11 (91.7%). Conclusion: Non-invasive methods, tested in the study, have different diagnostic properties when differentiating particular clinical types of lesions. They are highly sensitive to changes in the oral mucosa but the final diagnosis must always be proved with biopsy.

Diagnostic Properties of a Portable Point-of-Care Method to Measure Bilirubin and a Transcutaneous Bilirubinometer

<b><i>Background:</i></b> Recently, the Bilistick®, a point-of-care instrument to measure bilirubin levels, has been developed. It is fast and cheaper than transcutaneous bilirubin (TCB)-measuring devices, but data on diagnostic properties are scarce. <b><i>Objective:</i></b> This study aimed to compare the performance of the Bilistick® (BM-BS 1.0 – FW version 2.0.1) and the JM-105 bilirubinometer for measuring bilirubin. <b><i>Method:</i></b> This is a prospective study in infants born after ≥32 weeks’ gestation, and/or a birth weight of ≥1,500 g, and a postnatal age ≤14 days in Surabaya, Indonesia. Bilirubin was measured with the Bilistick® System (BM-BS 1.0 – FW version 2.0.1), transcutaneously (TCB) with the JM-105 bilirubinometer, and in serum (TSB) with a routine laboratory technique. Mean differences and 95% limits of agreement (LOA) and correlations were calculated. <b><i>Result:</i></b> We enrolled 149 neonates and 126 had paired measurements of Bilistick® bilirubin, TCB, and TSB. Bilistick® failed in 16 (10.7%) infants. Mean Bilistick® bilirubin-TSB difference was −11 µmol/L (95% LOA: −101 to 79 µmol/L) and <i>r</i> = 0.738 (<i>p</i> &#x3c; 0.001). Mean TCB-TSB difference was 26 μmol/L (95% LOA: −33 to 88) and <i>r</i> = 0.785 (<i>p</i> &#x3c; 0.001). The sensitivity, specificity, PPV, and NPV for Bilistick® bilirubin for a TSB above treatment thresholds were 0.74, 0.84, 0.67, and 0.88, respectively, and for TCB 0.92, 0.64, 0.54, and 0.95, respectively. <b><i>Conclusion:</i></b> The Bilistick® System (BM-BS 1.0 – FW version 2.0.1) underestimates TSB, whereas TCB overestimates TSB in jaundiced Indonesian infants. Further improvement of Bilistick®’s diagnostic accuracy with less false-negative readings is essential to increase its use.

Allergic activity and specificity of tuberculin preparations with 30-50% of weakly secreted mycobacterial antigens of tuberculosis

Bovine tuberculosis remains a global problem. An intracutaneous test with tuberculin is the main method for determining the status of herds, which poses special requirements for the activity and specificity. The basis of cotemporal tuberculins are antigens of tuberculosis mycobacteria easily secreted to the liquid synthetic medium during growth, but a range of antigens with a low secretion index are in composition of tuberculins in small quantities. The purpose of the research is to obtain weakly secreted antigens from a production waste – autoclaved bacterial mass of production strain of tuberculosis mycobacteria (MTB) using ultrasound and nonionic detergent, to study the diagnostic properties of tuberculosis with 30-50% of such antigens. It has been determined that autoclaved bacterial mass of industrial MBT strain, which is a waste of tuberculin production, can be an additional source of tuberculoproteins, which are low-secreting (LS) MBT antigens, which in an equivalent dose are about 30% more active compared to standard tuberculin based on easily secreted antigens and is not inferior in terms of species specificity. Whereas, up to 50% of purified LS of tuberculoproteins from the bacterial mass can be included in tuberculin composition. The obtained preparation is not reactogenic, in an equivalent dose it does not differ in terms of activity from the international standard for PPD of tuberculin, but surpasses it in terms of species specificity. It has been shown that in herds with an undetermined tuberculosis status, 2.2 times more cows respond to tuberculins with 30-50% of purified LS tuberculoproteins compared to standard preparations based on easily secreted antigens of tuberculosis mycobacterium. Profound studies of reacting cows using methods for detecting the genome of tuberculosis mycobacterium and bacteriological markers of tuberculosis infection have confirmed the presence of latent tuberculosis infection in cow body. The inclusion of up to 50% of tuberculoproteins from the bacterial mass in tuberculin increases the diagnostic properties of the target product and significantly reduces its price cost.

Validation of 19-items wearing-off (WOQ-19) questionnaire to Portuguese

ABSTRACT Background: The treatment of Parkinson disease with dopaminergic therapy improves functionality and quality of life. However, as the disease progresses, the wearing-off phenomenon develops. To improve the recognition of this phenomenon, the 19-item wearing-off questionnaire (WOQ-19) was developed. Objective: To translate and validate the WOQ-19 into Portuguese. Methods: The questionnaire was translated into Portuguese and, subsequently, back-translated into English and analyzed. The final version was tested in Parkinson disease patients for reliability through the test-retest paradigm and internal consistency. Also, sensitivity and specificity were obtained in different cut-off positive items. Results: The WOQ-19 showed good test stability, with an intraclass correlation coefficient of 0.877 (95%CI 0.690-0.951; p<0.001), and good internal consistency, with Cronbach alpha of 0.815. Two items of positive cut-off showed the best accuracy: 0.873 (95%CI 0.791-0.954). Sensitivity was 0.975 (95%CI 0.892-1) and specificity was 0.714 (95%CI 0.565-0.863). Conclusion: The Portuguese version of the WOQ-19 showed excellent diagnostic properties and can be used to diagnose wearing-off phenomena.