Composite Gold Standard Research Articles

Respiratory triggered diffusion-weighted imaging with a single diffusion sensitising gradient to reduce image acquisition time – A feasibility study in the workup of hepatocellular carcinoma

PurposeWe evaluated respiratory triggered unidirectional single-shot echo-planar imaging (u-SSEPI) as a time-saving measure in diffusion imaging of the upper abdomen. Specifically, we compared the ADC values obtained from unidirectional DWI (u-SSEPI) and routine DWI (4t-SSEPI) and also the diagnostic accuracies of unidirectional and routine DWI sequences in the identification of focal liver lesions in the setting of chronic liver disease (CLD). Materials and methodsThis prospective, IRB approved study, included 48 patients of CLD who underwent-DCE-MRI on a 1.5 T scanner for hepatocellular carcinoma (HCC) workup. In addition to 4t-SSEPI, u-SSEPI was acquired with the diffusion sensitising gradient being applied in only one direction; keeping all other parameters same as 4t-SSEPI. Two blinded radiologists evaluated the DWI studies for image quality and detection of liver lesions. A composite gold standard was established using DCE-MRI, follow-up imaging and patient clinical details. The apparent diffusion coefficients (ADCs) of the liver, spleen and the lesions were compared between the two sequences. ROC analysis evaluated the diagnostic accuracy of ADC from both the sequences in identifying HCC. ResultsEighty-eight lesions were identified using the composite gold standard. u-SSEPI resulted in 3 times faster image acquisition. No statistically significant differences were demonstrated between the unidirectional and routine DWI sequences for image quality parameters and lesion detection rates. Lesion wise comparison of the ADC values from both the sequences was not statistically different (p = 0.8) with a coefficient of variation = 12–14 %. The Bland- Altman plots and the Passing-Bablock regression analysis demonstrated a systematic and proportional bias between the ADC values obtained. The AUC of the ROC curve, however, was 0.63–observer1; 0.62–oobserver2 for routine DWI and 0.65; 0.62 for unidirectional DWI when ADC was used to identify HCC (the AUCs were not statistically different (p = 0.6−0.8)). ConclusionNo significant differences were demonstrated in the diagnostic accuracies of unidirectional and routine DWI in the diagnosis of HCC. Unidirectional diffusion may be further evaluated in other organs where diffusion is isotropic, especially in respiratory triggered sequences where the imaging time dividend is significant.

1219. Diagnosing vaginal discharge syndrome and its potential impact on clinical practice in a regional hospital in Taiwan

BackgroundVaginal discharges are frequently encountered in clinical practice and usually managed empirically. We aimed to investigate the prevalence of bacterial vaginosis (BV), vulvovaginal candidiasis (VVC) and trichomoniasis among adult women of reproductive age and evaluate the appropriateness of empirical treatment.MethodsNon-pregnant women between the age of 20 and 49 years who presented with vaginal discharge were prospectively enrolled in a teaching hospital since Oct 2018. Vaginal swabs were collected for determination of Nugent score, culture for Trichomonas vaginalis (TV) and Candida species, and multiplex polymerase chain reaction (PCR) for BV, VVC and TV. Demographics, symptoms, physical findings, and the empirical treatment were recorded.ResultsFrom Oct 2018 to May 2020, 172 women were included (median age, 37 years). The prevalence of laboratory confirmed BV, VVC, and TV was 21.5% (n=37), 20.3% (35), and 0.6% (1), respectively. Ten (5.8%) women had concurrent BV and VCC. Among 38 women who had bacterial vaginosis or trichomoniasis, only 8 (21.1%) received metronidazole empirically while more than half (11/19, 57.9%) of women who received metronidazole empirically did not have laboratory-confirmed bacterial vaginosis or trichomoniasis. Among 35 women who had candidiasis, 10 (28.6%) received antifungal agents. Antifungal agents were prescribed to more than two thirds (21/31, 67.7%) of women who did not have laboratory confirmed candidiasis. Overall, 58.7% (101/172) of empirical treatment was deemed optimal. Multiplex PCR test has an overall diagnostic accuracy of 86.0% (148/172) as compared to the composite gold standard.ConclusionThe empirical treatment for vaginal discharge syndrome is suboptimal. Better diagnostic assays have a potential to improve clinical patient care.Disclosures All Authors: No reported disclosures

Evaluation of real time polymerase chain reaction targeting mpb64 gene for diagnosis of extrapulmonary tuberculosis

BackgroundPaucibacillary nature of extrapulmonary tuberculosis (EPTB) has paved way for molecular methods increasingly being used for diagnosis. We undertook a study for evaluation of sensitivity and specificity of real-time polymerase chain reaction (RT-PCR) targeting mpb64 gene for diagnosis of EPTB. MethodsA total of 152 clinical samples from suspected cases of EPTB were included in this study. All samples were extracted using spin column based commercial DNA extraction kit and were subjected to RT-PCR targeting mpb64 and IS6110. Smear and culture was also done for samples whenever quantity was sufficient. Cytology report was noted from hospital information system. Receiver operating characteristic (ROC) curve analysis was done for determining cut-off Ct value for mpb64 RT-PCR. Melt curve analysis was done for samples whose cycle threshold (Ct) value was more than 37. The sensitivity and specificity of the mpb64 RT-PCR was calculated using a composite gold standard i.e., positive for one or more of the following: microscopy (including fine needle aspiration cytology (FNAC), acid-fast bacilli positivity), culture and IS6110 RT-PCR. ResultsOut of the 152 samples, 72 (47.4%) were positive for tuberculosis by composite gold standard. Samples consisted of ascitic fluid (12), CSF (35), pus (23), lymph node aspirate (35), pleural fluid (37), synovial fluid (4), urine (1), pericardial fluid (1) and tissue bits (4). Microscopy (AFB smear including lymph node aspirate) was done for 124 samples of which 43 (34.7%) were positive. Culture results were available for 79 samples, 25 (31.6%) of which were positive and 42 (27.6%) of the 152 samples were positive by IS6110 PCR. Based on ROC and melt curve analysis, mpb64 RT-PCR was able to detect 38 (52.8%) of the 72 positive samples. In comparison to IS6110 RT PCR, 4 additional cases were detected by mpb64 RT-PCR. Compared to composite gold standard mpb64 showed overall sensitivity of 52.8%. ConclusionThe mpb64 RT-PCR is highly specific or MTB and can be used as a supplemental test for diagnosis of EPTB along with other diagnostic tests. However the overall sensitivity of mpb64 RT-PCR is too low to be used as an independent test for diagnosis of EPTB. Combining the results of IS6110 RT PCR and mpb64 RT PCR improved the overall sensitivity and hence mpb64 can be used as an additional target for diagnosis of EPTB.

11C-choline positron emission tomography/computed tomography for detection of disease relapse in patients with history of biochemically recurrent prostate cancer and prostate-specific antigen ≤0.1 ng/ml.

The objective was to evaluate the diagnostic performance of surveillance11 C-choline positron emission tomography/computed tomography (PET/CT) for the detection of disease relapse in patients with a history of biochemically recurrent (BCR) prostate cancer (PCa) and prostate-specific antigen (PSA) ≤0.1 ng/ml. We included patients who had been treated for BCR PCa and had a surveillance11 C-choline PET/CT at serum PSA ≤0.1 ng/ml. Positive surveillance PET/CT was defined as a study that identified a new tracer-avid lesion or new tracer uptake in a previously treated lesion or both. Findings were confirmed against a composite radiologic-pathologic gold standard. Time to recurrence association analyses were performed for disease relapse risk with the use of Cox proportional hazards regression. In total, 13 (12.1%) of the 107 patients had positive surveillance PET/CT scans, confirmed on pathologic assessment (n = 5) and subsequent imaging (n = 8). Among these 13 patients, ten had distant metastases, two had local recurrence, and one had both. Nine of the ten patients with metastases had oligometastatic disease defined as the presence of ≤3 metastases. Serum PSA became detectable again in only seven patients with positive surveillance PET/CT, after a mean interval from surveillance PET/CT of 292 days (range: 105-543 days). We identified an association of N stage with increased risk of recurrence (hazard ratio = 3.85; P = 0.036) although this was not significant after accounting for multiple testing. Surveillance11 C-choline PET/CT can detect early disease relapse at serum PSA ≤0.1 ng/ml in patients with a history of BCR PCa.

Fever in the returned traveller: the utility of the Platelia Dengue NS1 antigen enzyme immunoassay for the diagnosis of dengue in a non-endemic setting

Investigating fever in the returned traveller can be difficult and costly. Dengue is one of the most frequently reported aetiologies. NS1 is a non-structural dengue virus protein detectable during acute infection. The aim of this report is to describe the utility of the Platelia Dengue NS1 antigen enzyme immunoassay (EIA) for detection of dengue in a non-endemic region compared to a composite gold standard of contemporaneous molecular testing and seroconversion. We performed a retrospective analysis of all dengue serology tests from 6 February 2012 to 5 December 2018. Dengue serology and in-house flavivirus molecular results were identified using the laboratory information management system. Dengue serology was performed using the Bio-Rad Platelia Dengue NS1 antigen EIA, and Abbott Panbio Dengue IgG and IgM EIA. True positive NS1 result was defined as positive molecular test within one week of the positive NS1 result or seroconversion within 120 days. NS1 negative samples that remained negative to all dengue markers on repeat more than 10 and up to 120 days after were labelled as true negatives. More than 75% of cases had a serology pattern consistent with primary dengue. Sensitivity and specificity of NS1 Ag EIA was 96.4% (95% CI 92.3-98.7%) and 98.4% (95% CI 94.5-99.8%), respectively. Performance was poorer in serotype 4 infections (sensitivity 50%). Platelia Dengue NS1 antigen EIA test performance in the returned traveller cohort fulfils the remit as a single diagnostic test for acute dengue infection.

Role of Gene Xpert in the Detection of Genital Tuberculosis in Endometrial Tissue among Women with Infertility.

Objective:The objective of the study is to evaluate the clinical utility of Gene Xpert compared with other available diagnostic modalities in prompt diagnosis of female genital tuberculosis (TB) causing infertility.Material and Methods:This was a prospective, cross-sectional analytical study. Premenstrual endometrial biopsy specimens were collected from 176 infertile women of reproductive age group suspected of having genital TB. Samples were processed for acid-fast bacilli, culture, histopathology, polymerase chain reaction (PCR), and Gene Xpert. Patients detected positive on Gene Xpert and PCR were subjected to laparoscopy to look for affirmative findings of genital TB. The results were analyzed using composite gold standard consisting of patients positive with culture, histopathology, and laparoscopy.Results:A total of 18 patients were found positive using composite gold standard. Laparoscopy was positive in 15 patients, whereas culture and histopathology were positive in three and two patients, respectively. Gene Xpert was positive in two patients. None of them was detected with rifampicin resistance. The sensitivity of Gene Xpert was 11.11% whereas the specificity was 100%.Conclusion:Since genital TB is a paucibacillary disease, multiple diagnostic modalities are needed for diagnosis. Gene Xpert appears to be a useful modality in diagnosis of genital TB, owing to its high specificity, and can be recommended in conditions where microscopy, culture, and histopathology are negative; however, further randomized studies are required to support our hypothesis.

Texture analysis of routine T2 weighted fat-saturated images can identify head and neck paragangliomas – A pilot study

PurposeTo evaluate the role of the first and second-order texture parameters obtained from T2-weighted fat-saturated DIXON images in differentiating paragangliomas from other neck masses, and to develop a statistical model to classify them. MethodWe retrospectively evaluated 38 paragangliomas, 18 nerve-sheath tumours and 14 other miscellaneous neck lesions obtained from an IRB approved study conducted between January 2016 and June 2019; using a composite gold standard of histopathology, cytology and DOTANOC PET CT (A total of 70 lesions in 63 patients). Fat-suppressed T2weighted-DIXON axial images were used. First and second-order texture-parameters were calculated from the original and filtered images. Feature selection using F-statistics and collinearity analysis provided 14 texture parameters for further analysis. Mann-Whitney-U test was used to compare between the groups and p-values were adjusted for multiple comparisons. ROC curve analysis was used to obtain optimal cut-offs. ResultsA total of ten texture features were found to be significantly different between paragangliomas and non-paraganglioma lesions. Minimum from the histogram of grey levels was lower in paragangliomas with a cut off of ≤113.462 obtaining 62.9 % sensitivity and 77.27 % specificity in differentiating paragangliomas from non-paragangliomas. Logistic regression model was trained (n-49) using forward feature selection, which when evaluated on the validation set(n-21)- obtained an AUC of 0.855(95 %CI, 0.633 to 0.968) with a positive likelihood ratio of 4.545 (95 %CI, 1.298–15.923) in differentiating paragangliomas from non-paragangliomas. ConclusionTexture analysis of a routine imaging sequence can identify paragangliomas with high accuracy. Further development of texture analysis would enable better imaging workflow, resource utilisation and imaging cost reductions.

Partial verification bias and incorporation bias affected accuracy estimates of diagnostic studies for biomarkers that were part of an existing composite gold standard

ObjectiveTo investigate how choice of gold standard biases estimates of sensitivity and specificity in studies reassessing the diagnostic accuracy of biomarkers that are already part of a lifetime composite gold standard (CGS). Study Design and SettingWe performed a simulation study based on the real-life example of the biomarker “protein 14-3-3” used for diagnosing Creutzfeldt–Jakob disease. Three different types of gold standard were compared: perfect gold standard “autopsy” (available in a small fraction only; prone to partial verification bias), lifetime CGS (including the biomarker under investigation; prone to incorporation bias), and “best available” gold standard (autopsy if available, otherwise CGS). ResultsSensitivity was unbiased when comparing 14-3-3 with autopsy but overestimated when using CGS or “best available” gold standard. Specificity of 14-3-3 was underestimated in scenarios comparing 14-3-3 with autopsy (up to 24%). In contrast, overestimation (up to 20%) was observed for specificity compared with CGS; this could be reduced to 0–10% when using the “best available” gold standard. ConclusionChoice of gold standard affects considerably estimates of diagnostic accuracy. Using the “best available” gold standard (autopsy where available, otherwise CGS) leads to valid estimates of specificity, whereas sensitivity is estimated best when tested against autopsy alone.

Characterization of lesions in dense breasts: Does tomosynthesis help?

Context:Mammography in dense breasts is challenging due to lesion obscuration by tissue overlap. Does tomosynthesis offers a solution?Aims:To study the impact of digital breast tomosynthesis (DBT) in characterizing lesions in breasts of different mammographic densities.Settings and Design:Prospective blinded study comparing mammography in two views with Mammography + Tomosynthesis.Methods and Material:Tomosynthesis was performed in 199 patients who were assigned Breast imaging reporting and data system (BIRADS) categories 0, 3, 4, or 5 on two-dimensional (2D) mammogram. Mammograms were first categorized into one of 4 mammographic breast densities in accordance with the American College of Radiology (ACR). Three radiologists independently analyzed these images and assigned a BIRADS category first based on 2D mammogram alone, and then assigned a fresh BIRADS category after taking mammography and tomosynthesis into consideration. A composite gold-standard was used in the study (histopathology, ultrasound, follow-up mammogram, magnetic resonance imaging). Each lesion was categorized into 3 groups—superior categorization with DBT, no change in BIRADS, or inferior BIRADS category based on comparison with the gold-standard. The percentage of lesions in each group was calculated for different breast densities.Results:There were 260 lesions (ages 28–85). Overall, superior categorization was seen in 21.2% of our readings on addition of DBT to mammography. DBT was most useful in ACR Densities 3 and 4 breasts where it led to more appropriate categorization in 27 and 42% of lesions, respectively. DBT also increased diagnostic confidence in 54.5 and 63.6% of lesions in ACR Densities 3 and 4, respectively.Conclusions:In a diagnostic setting, the utility of tomosynthesis increases with increasing breast density. This helps in identifying the sub category of patients where DBT can actually change management.

Utility of multiplex real-time PCR in the diagnosis of extrapulmonary tuberculosis

ObjectiveThe diagnosis of extrapulmonary tuberculosis is still a challenge because of its pauci-bacillary nature. The aim of the study was to evaluate the role of a multiplex PCR assay in the diagnosis of extrapulmonary tuberculosis and to compare the efficiency of two targets, IS6110 and MPB64 to detect Mycobacterium tuberculosis. Methods150 extrapulmonary samples (61 pus/aspirate, 46 tissue, 32 body fluids, and 11 urine) from clinically suspected cases of tuberculosis were included in the study. All the samples were subjected to direct fluorescent microscopy, TB culture (BacT/ALERT 3D, biomerieux, Durham, North Carolina, USA) and a Multiplexed Tandem PCR targeting two mycobacterial DNA sequences, IS6110 and MPB64. Master-Mix reagents and primers were prepared by AusDiagnostics Pvt. Ltd (Alexandria, New South Wales, Australia). The performance of the assay was assessed using a composite gold standard, which included clinical characteristics, microbiology smear as well as culture, histopathology, cytology, radiology, and response to antitubercular therapy. Results20.3%, 23.6%, and 45.3% of specimens were positive by smear, culture, and PCR, respectively. The sensitivity and specificity of the multiplex PCR was 91.9% and 88.4%, respectively, using the composite gold standard. Positive and negative predictive values of the PCR were estimated as 85.1% and 93.8%, respectively. Higher positivity was observed with target IS6110 (44.6%) as compared to target MPB64 (18.9%). The sensitivities of IS6110 and MPB64 individual targets were 90.3% and 64.5%, respectively, and specificities were 88.4% and 97.7%, respectively. ConclusionPCR can play an important role in rapid and accurate diagnosis of extrapulmonary tuberculosis. IS6110 alone is an effective target in our part of the country.

Xpert MTB/Rif for the diagnosis of extrapulmonary tuberculosis--an experience from a tertiary care centre in South India.

The Xpert MTB/Rif, with a detection limit of 131 CFU/ml, plays a valuable role in the diagnosis of extrapulmonary tuberculosis, both susceptible and resistant. This study aims at evaluating the Xpert MTB/Rif for the same, at a tertiary care centre in south India, assessing it against both culture and a composite gold standard (CGS). We tested consecutive samples from patients suspected of extrapulmonary tuberculosis with Xpert MTB/Rif, evaluated its sensitivity and specificity against solid and/or liquid culture and CGS. An individual analysis of different sample types (tissue biopsies, fluids, pus, lymph node biopsies and CSF) given an adequate sample size, against both culture and CGS, was also performed. In total, 494 samples were analysed against culture. Compared to culture, the sensitivity of Xpert MTB/Rif was 89% (95% CI 0.81-0.94) and its specificity was 74% (95% CI 0.70-0.78). When Xpert MTB/Rif was compared to the CGS, pooled sensitivity was 62% (95% CI 0.56-0.67) and specificity was 100% (95% CI 0.91-1.00). This assay performs better than the currently available conventional laboratory methods. The rapidity with which results are obtained is an added advantage, and its integration into a routine diagnostic protocol must be considered.

Post-PET ultrasound improves specificity of 18F-FDG-PET for recurrent differentiated thyroid cancer while maintaining sensitivity.

BackgroundPositron emission tomography (PET) using fluor-18-deoxyglucose (18F-FDG) with or without computed tomography (CT) is generally accepted as the most sensitive imaging modality for diagnosing recurrent differentiated thyroid cancer (DTC) in patients with negative whole body scintigraphy with iodine-131 (I-131).PurposeTo assess the potential incremental value of ultrasound (US) over 18F-FDG-PET-CT.Material and MethodsFifty-one consecutive patients with suspected recurrent DTC were prospectively evaluated using the following multimodal imaging protocol: (i) US before PET (pre-US) with or without fine needle biopsy (FNB) of suspicious lesions; (ii) single photon emission computed tomography (≥3 GBq I-131) with co-registered CT (SPECT-CT); (iii) 18F-FDG-PET with co-registered contrast-enhanced CT of the neck; (iv) US in correlation with the other imaging modalities (post-US). Postoperative histology, FNB, and long-term follow-up (median, 2.8 years) were taken as composite gold standard.ResultsFifty-eight malignant lesions were identified in 34 patients. Forty lesions were located in the neck or upper mediastinum. On receiver operating characteristics (ROC) analysis, 18F-FDG-PET had a limited lesion-based specificity of 59% at a set sensitivity of 90%. Pre-US had poor sensitivity and specificity of 52% and 53%, respectively, increasing to 85% and 94% on post-US, with knowledge of the PET/CT findings (P < 0.05 vs. PET and pre-US). Multimodal imaging changed therapy in 15 out of 51 patients (30%).ConclusionIn patients with suspected recurrent DTC, supplemental targeted US in addition to 18F-FDG-PET-CT increases specificity while maintainin sensitivity, as non-malignant FDG uptake in cervical lesions can be confirmed.

Recombinase polymerase amplification-based assay to diagnose Giardia in stool samples.

Giardia duodenalis is one of the most commonly identified parasites in stool samples. Although relatively easy to treat, giardiasis can be difficult to detect as it presents similar to other diarrheal diseases. Here, we present a recombinase polymerase amplification-based Giardia (RPAG) assay to detect the presence of Giardia in stool samples. The RPAG assay was characterized on the bench top using stool samples spiked with Giardia cysts where it showed a limit-of-detection nearly as low as the gold standard polymerase chain reaction assay. The RPAG assay was then tested in the highlands of Peru on 104 stool samples collected from the surrounding communities where it showed 73% sensitivity and 95% specificity against a polymerase chain reaction and microscopy composite gold standard. Further improvements in clinical sensitivity will be needed for the RPAG assay to have clinical relevance.

Reply to the Letter to the Editor: Another Look: Is There a Flaw to Current Hip Septic Arthritis Diagnostic Algorithms?

Reply to the Letter to the Editor: Another Look: Is There a Flaw to Current Hip Septic Arthritis Diagnostic Algorithms?

Evaluation of various laboratory assays in detection of heparin‐induced thrombocytopenia in an adult general ICU

Heparin-induced thrombocytopenia (HIT) is an immune-mediated complication of heparin therapy. Our objective was (i) to compare various laboratory assays for HIT against clinical probability (4-T score) and (14) C-serotonin release assay (SRA), which was the composite gold standard and (ii) to determine the incidence of HIT in the ICU. The study group (n = 217) consisted of consecutive ICU patients with heparin exposure followed by thrombocytopenia. The clinical probability (4-T score) was applied to the study group. Enzyme-linked immunosorbent assay (ELISA), particle gel immunoassay (PGIA), SRA, and platelet aggregation assay (PAA) were performed. The 4-T score showed that 1/217 patients had high probability, 48 had intermediate probability, and 168 had low probability for HIT. One patient was positive by SRA, three by PGIA, and 33 by ELISA. The incidence based on a combination of clinical features and laboratory findings was 1.8%. A greater number of false positives were observed by ELISA than by PGIA when compared to a composite gold standard of SRA and clinical probability. The incidence of SRA-positive HIT was 0.46% (1/217).

Endoscopic-Ultrasound-Guided Tissue Sampling Facilitates the Detection of Local Recurrence and Extra Pelvic Metastasis in Pelvic Urologic Malignancy

Pelvic lymph node dissection is the gold standard for assessing nodal disease in prostate or bladder cancer and is superior to CT, MRI and PET staging. Endoscopic ultrasound (EUS) provides an alternative, less invasive method of cytohistologic material acquisition, but its performance in pelvic urologic malignancy is unknown. Therefore, our aim was to evaluate the diagnostic accuracy of EUS guided tissue sampling for these malignancies when compared to a composite cytohistologic and surgical gold standard. A median of 3 FNA passes were performed (n = 19 patients) revealing a sensitivity, specificity, PPV and NPV of 94.4% (72–99), 100% (2–100), 100% (80–100) and 50% (1–98) respectively. The perirectal space was the most frequently sampled location irrespective of the primary urological cancer origin. Final diagnosis established by EUS tissue sampling included bladder cancer (n = 1), bladder cancer local recurrence (n = 8), bladder cancer extra pelvic metastases (n = 1), prostate cancer (n = 2), prostate cancer local recurrence (n = 4), prostate cancer extra pelvic metastases (n = 1), testicular cancer extra pelvic metastases (n = 1) and a benign seminal vesicle (n = 1). EUS guided sampling of the gut wall, lymph nodes, or perirectal space yields suitable diagnostic material to establish the presence of primary, local recurrence or extra pelvic metastases of pelvic urologic malignancy.

MR evaluation of biliary-enteric anastomotic stricture: Does contrast-enhanced T1W MRC provide additional information?

To compare T2W-MRCP and T1W contrast-enhanced MRC (CE-MRC) using Gd-BOPTA for evaluation of biliary-enteric anastomotic (BEA) stricture. Twenty-one patients who were suspected to have BEA stricture underwent T2W-MRCP and CE-MRC on a 1.5T scanner. Images were evaluated for evidence of anastomotic stricture. Composite gold standard was used including the findings on percutaneous transhepatic cholangiogram or percutaneous transhepatic biliary dilatation, surgery, alkaline phosphatase level and clinical follow-up. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of T2W-MRCP for the diagnosis of anastomotic stricture were 94.4%, 80%, 94.4% and 80% respectively. On CE-MRC, biliary excretion was seen in only 60.87% anastomoses and only these were taken for analysis. The sensitivity, specificity, PPV and NPV of CE-MRC for the diagnosis of anastomotic stricture were 40%, 75%, 80% and 33.3%. The combined evaluation of T2W-MRCP and CE-MRC showed sensitivity, specificity, PPV and NPV of 83.3%, 80%, 93.8% and 57.1%. At present, T2W-MRCP is still the diagnostic modality of choice in the evaluation of patients with BEA stricture and the usage of Gd-BOPTA enhanced MRC is inappropriate in this setting.

Case finding of lifestyle and mental health disorders in primary care: validation of the ‘CHAT’ tool

Primary care is accessible and ideally placed for case finding of patients with lifestyle and mental health risk factors and subsequent intervention. The short self-administered Case-finding and Help Assessment Tool (CHAT) was developed for lifestyle and mental health assessment of adult patients in primary health care. This tool checks for tobacco use, alcohol and other drug misuse, problem gambling, depression, anxiety and stress, abuse, anger problems, inactivity, and eating disorders. It is well accepted by patients, GPs and nurses. To assess criterion-based validity of CHAT against a composite gold standard. Conducted according to the Standards for Reporting of Diagnostic Accuracy statement for diagnostic tests. Primary care practices in Auckland, New Zealand. One thousand consecutive adult patients completed CHAT and a composite gold standard. Sensitivities, specificities, positive and negative predictive values, and likelihood ratios were calculated. Response rates for each item ranged from 79.6 to 99.8%. CHAT was sensitive and specific for almost all issues screened, except exercise and eating disorders. Sensitivity ranged from 96% (95% confidence interval [CI] = 87 to 99%) for major depression to 26% (95% CI = 22 to 30%) for exercise. Specificity ranged from 97% (95% CI = 96 to 98%) for problem gambling and problem drug use to 40% (95% CI = 36 to 45%) for exercise. All had high likelihood ratios (3-30), except exercise and eating disorders. CHAT is a valid and acceptable case-finding tool for most common lifestyle and mental health conditions.

Endoscopic Ultrasound and IL-8 in Pancreatic Juice to Diagnose Chronic Pancreatitis

Background/Aim: Pancreatic juice (PJ) [IL-8] has been proposed as a marker for pancreatic diseases. We compared the accuracy of PJ [IL-8] and endoscopic ultrasound (EUS) to diagnose chronic pancreatitis (CP). Methods: 79 patients with symptoms suspicious for CP were enrolled. PJ emptied into the duodenum was collected during an upper endoscopy with IV secretin and [IL-8] was measured. CP was diagnosed when PJ [IL-8] was >20 pg/ml. CP was diagnosed at EUS when ≥4 of the 9 established criteria were present. CP was diagnosed by using composite gold standard: ERCP, histology, CT or MRI, and clinical follow-up (mean 20 months). Results: 38 patients had CP, whereas 41 patients had no pancreatic disease. To diagnose CP, PJ [IL-8] was significantly less sensitive compared to EUS (47 vs. 71%), but equally accurate (71 vs. 80%) and specific (93 vs. 88%). By combining PJ [IL-8] and EUS, sensitivity and specificity significantly increased to 82% (either IL-8 or EUS positive) and 100% (both IL-8 and EUS positive). Conclusions: Both PJ [IL-8] and EUS are accurate diagnostic modalities for CP. PJ collection can be performed at the time of EUS. PJ [IL-8] and EUS are complementary with higher sensitivity and specificity when used together.

Accuracy of Endoscopic Ultrasonography and Magnetic Resonance Cholangiopancreatography for the Diagnosis of Chronic Pancreatitis

The diagnosis of chronic pancreatitis (CP) remains challenging. Endoscopic ultrasound (EUS) and magnetic resonance cholangiopancreatography (MRCP) have been proposed as highly accurate diagnostic modalities. Although endoscopic retrograde cholangiopancreatography (ERCP) has been previously used as a gold standard, it is associated with a small but significant risk. We aim to compare the accuracy of EUS and MRCP with the composite gold standard using ERCP, surgical pathology, and/or long-term clinical follow-up. Ninety-nine patients with clinical signs and/or symptoms suggestive of CP were prospectively enrolled. The diagnosis of CP by MRCP was established when one or more of these features were present: main duct dilation without obstruction, dilated side branches, intraductal stones, ductal irregularity, reduced T1-signal intensity, parenchymal atrophy, and reduced secretory response to secretin administration. The diagnosis of CP by EUS was made when 4 or more of the established criteria were present. Accuracy of all criteria used ("EUS only," "MRCP only," "either EUS or MRCP," and "both EUS and MRCP") was compared with the composite gold standard. Forty patients were diagnosed with CP by the composite gold standard whereas the remaining 59 patients were controls. EUS only seemed more sensitive but equally specific compared with MRCP only to diagnose CP. The combination of EUS and MRCP had a sensitivity of 98% for either EUS or MRCP and a specificity of 100% for both EUS and MRCP. EUS and MRCP are highly accurate modalities for the diagnosis of CP and are complementary when used together. If confirmed in larger series, the diagnosis of CP by both EUS and MRCP is highly predictive and ERCP is unlikely to add any useful information.