Effect of educational lecture on the diagnostic accuracy of Japan NBI Expert Team classification for colorectal lesions

Abstract Background An educational and training program is required for generalization of Japan NBI Expert Team (JNET) classification. However, there is no detailed report on the learning curve of the diagnostic accuracy of endoscopists using JNET classification. We examined the effect of an educational lecture on beginners and less experienced endoscopists for improving their diagnostic accuracy of colorectal lesions by JNET classification. Methods Seven beginners with no endoscopy experience (NEE group), 7 less experienced endoscopists (LEE group), and 3 highly experienced endoscopists (HEE group) performed diagnosis using JNET classification for randomized NBI images of colorectal lesions from 180 cases (Type 1: 22 cases, Type 2A: 105 cases, Type 2B: 33 cases, and Type 3: 20 cases). Next, the NEE and LEE groups received a lecture on JNET classification, and all 3 groups repeated the diagnostic process. We compared the correct diagnosis rate and interobserver agreement before and after the lecture comprehensively and for each JNET type. Results In the HEE group, the correct diagnosis rate was more than 90% with good interobserver agreements (kappa value: 0.78–0.85). In the NEE and LEE groups, the correct diagnosis rate (NEE: 60.2 → 68.0%, P < 0.01; LEE: 66.4 → 86.7%, P < 0.01), high-confidence correct diagnosis rate (NEE: 19.6 → 37.2%, P < 0.01; LEE: 43.6 → 61.1%, P < 0.01), and interobserver agreement (kappa value, NEE: 0.32 → 0.43; LEE: 0.39 → 0.75) improved after the lecture. In the examination by each JNET type, the specificity and positive predictive value in the NEE and LEE groups generally improved after the lecture. Conclusion After conducting an appropriate lecture, the diagnostic ability using JNET classification was improved in beginners or endoscopists with less experience in NBI magnifying endoscopy.

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Correlation between Optic Nerve Parameters Obtained Using 3D Nonmydriatic Retinal Camera and Optical Coherence Tomography: Interobserver Agreement on the Disc Damage Likelihood Scale

Journal of Ophthalmology ◽

10.1155/2014/931738 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Jae Wook Han ◽

Soon Young Cho ◽

Kui Dong Kang

Keyword(s):

Optical Coherence Tomography ◽

Optic Disc ◽

Interobserver Agreement ◽

Three Dimensional ◽

Weighted Kappa ◽

Optical Coherence ◽

Training Module ◽

Before And After ◽

Kappa Value ◽

Different Levels

Purpose. To compare stereometric parameters obtained by three-dimensional (3D) optic disc photography and optical coherence tomography (OCT) and assess interobserver agreement on the disc damage likelihood scale (DDLS).Methods. This retrospective study included 190 eyes from 190 patients classified as normal, glaucoma suspect, or glaucomatous. Residents at different levels of training completed the DDLS for each patient before and after attending a training module. 3D optic disc photography and OCT were performed on each eye, and correlations between the DDLS and various parameters obtained by each device were calculated.Results. We found moderate agreement (weighted kappa value, 0.59 ± 0.03) between DDLS scores obtained by 3D optic disc photography and the glaucoma specialist. The weighted kappa values for agreement and interobserver concordance increased among residents after the training module. Interobserver concordance was the poorest at DDLS stages 5 and 6. The DDLS scored by the glaucoma specialist had the highest predictability value (0.941).Conclusions. The DDLS obtained by 3D optic disc photography is a useful diagnostic tool for glaucoma. A supervised teaching program increased trainee interobserver agreement on the DDLS. DDLS stages 5 and 6 showed the poorest interobserver agreement, suggesting that caution is required when recording these stages.

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Imprecision of Laboratory Determinations and Diagnostic Accuracy: Theoretical Considerations

Methods of Information in Medicine ◽

10.1055/s-0038-1636147 ◽

1974 ◽

Vol 13 (03) ◽

pp. 151-158 ◽

Cited By ~ 5

Author(s):

D. A. B. Lindbebo ◽

Fr. R. Watson

Keyword(s):

Mathematical Model ◽

Diagnostic Accuracy ◽

Diagnostic Process ◽

Clinical Laboratories ◽

Non Linear ◽

Theoretical Considerations ◽

Made In

Recent studies suggest the determinations of clinical laboratories must be made more precise than at present. This paper presents a means of examining benefits of improvement in precision. To do this we use a mathematical model of the effect upon the diagnostic process of imprecision in measurements and the influence upon these two of Importance of Diagnosis and Prevalence of Disease. The interaction of these effects is grossly non-linear. There is therefore no proper intuitive answer to questions involving these matters. The effects can always, however, be calculated.Including a great many assumptions the modeling suggests that improvements in precision of any determination ought probably to be made in hospital rather than screening laboratories, unless Importance of Diagnosis is extremely high.

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AB1346-HPR REAL-WORLD EFFECTIVENESS AND PERCEIVED USEFULNESS OF SYMPTOM CHECKERS IN RHEUMATOLOGY: INTERIM REPORT FROM THE PROSPECTIVE MULTICENTER BETTER STUDY

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2020-eular.1604 ◽

2020 ◽

Vol 79 (Suppl 1) ◽

pp. 1961.1-1961

Author(s):

J. Knitza ◽

J. Mohn ◽

C. Bergmann ◽

E. Kampylafka ◽

M. Hagen ◽

...

Keyword(s):

Diagnostic Accuracy ◽

Real World ◽

Search Engines ◽

Correct Diagnosis ◽

Perceived Usefulness ◽

Symptom Duration ◽

Research Support ◽

Link Type ◽

The Mean ◽

Research Grant

Background:Symptom checkers (SC) promise to reduce diagnostic delay, misdiagnosis and effectively guide patients through healthcare systems. They are increasingly used, however little evidence exists about their real-life effectiveness.Objectives:The aim of this study was to evaluate the diagnostic accuracy, usage time, usability and perceived usefulness of two promising SC, ADA (www.ada.com) and Rheport (www.rheport.de). Furthermore, symptom duration and previous symptom checking was recorded.Methods:Cross-sectional interim clinical data from the first of three recruiting centers from the prospective, real-world, multicenter bETTeR-study (DKRS DRKS00017642) was used. Patients newly presenting to a secondary rheumatology outpatient clinic between September and December 2019 completed the ADA and Rheport SC. The time and answers were recorded and compared to the patient’s actual diagnosis. ADA provides up to 5 disease suggestions, Rheport calculates a risk score for rheumatic musculoskeletal diseases (RMDs) (≥1=RMD). For both SC the sensitivity, specificity was calculated regarding RMDs. Furthermore, patients completed a survey evaluating the SC usability using the system usability scale (SUS), perceived usefulness, previous symptom checking and symptom duration.Results:Of the 129 consecutive patients approached, 97 agreed to participate. 38% (37/97) of the presenting patients presented with an RMD (Figure 1). Mean symptom duration was 146 weeks and a mean number of 10 physician contacts occurred previously, to evaluate current symptoms. 56% (54/96) had previously checked their symptoms on the internet using search engines, spending a mean of 6 hours. Rheport showed a sensitivity of 49% (18/37) and specificity of 58% (35/60) concerning RMDs. ADA’s top 1 and top 5 disease suggestions concerning RMD showed a sensitivity of 43% (16/37) and 54% (20/37) and a specificity of 58% (35/60) and 52% (31/60), respectively. ADA listed the correct diagnosis of the patients with RMDs first or within the first 5 disease suggestions in 19% (7/37) and 30% (11/37), respectively. The average perceived usefulness for checking symptoms using ADA, internet search engines and Rheport was 3.0, 3.5 and 3.1 on a visual analog scale from 1-5 (5=very useful). 61% (59/96) and 64% (61/96) would recommend using ADA and Rheport, respectively. The mean SUS score of ADA and Rheport was 72/100 and 73/100. The mean usage time for ADA and Rheport was 8 and 9 minutes, respectively.Conclusion:This is the first prospective, real-world, multicenter study evaluating the diagnostic accuracy and other features of two currently used SC in rheumatology. These interim results suggest that diagnostic accuracy is limited, however SC are well accepted among patients and in some cases, correct diagnosis can be provided out of the pocket within few minutes, saving valuable time.Figure:Acknowledgments:This study was supported by an unrestricted research grant from Novartis.Disclosure of Interests:Johannes Knitza Grant/research support from: Research Grant: Novartis, Jacob Mohn: None declared, Christina Bergmann: None declared, Eleni Kampylafka Speakers bureau: Novartis, BMS, Janssen, Melanie Hagen: None declared, Daniela Bohr: None declared, Elizabeth Araujo Speakers bureau: Novartis, Lilly, Abbott, Matthias Englbrecht Grant/research support from: Roche Pharma, Chugai Pharma Europe, Consultant of: AbbVie, Roche Pharma, RheumaDatenRhePort GbR, Speakers bureau: AbbVie, Celgene, Chugai Pharma Europe, Lilly, Mundipharma, Novartis, Pfizer, Roche Pharma, UCB, David Simon Grant/research support from: Else Kröner-Memorial Scholarship, Novartis, Consultant of: Novartis, Lilly, Arnd Kleyer Consultant of: Lilly, Gilead, Novartis,Abbvie, Speakers bureau: Novartis, Lilly, Timo Meinderink: None declared, Wolfgang Vorbrüggen: None declared, Cay-Benedict von der Decken: None declared, Stefan Kleinert Shareholder of: Morphosys, Grant/research support from: Novartis, Consultant of: Novartis, Speakers bureau: Abbvie, Novartis, Celgene, Roche, Chugai, Janssen, Andreas Ramming Grant/research support from: Pfizer, Novartis, Consultant of: Boehringer Ingelheim, Novartis, Gilead, Pfizer, Speakers bureau: Boehringer Ingelheim, Roche, Janssen, Jörg Distler Grant/research support from: Boehringer Ingelheim, Consultant of: Boehringer Ingelheim, Paid instructor for: Boehringer Ingelheim, Speakers bureau: Boehringer Ingelheim, Peter Bartz-Bazzanella: None declared, Georg Schett Speakers bureau: AbbVie, BMS, Celgene, Janssen, Eli Lilly, Novartis, Roche and UCB, Axel Hueber Grant/research support from: Novartis, Lilly, Pfizer, Consultant of: Abbvie, BMS, Celgene, Gilead, GSK, Lilly, Novartis, Speakers bureau: GSK, Lilly, Novartis, Martin Welcker Grant/research support from: Abbvie, Novartis, UCB, Hexal, BMS, Lilly, Roche, Celgene, Sanofi, Consultant of: Abbvie, Actelion, Aescu, Amgen, Celgene, Hexal, Janssen, Medac, Novartis, Pfizer, Sanofi, UCB, Speakers bureau: Abbvie, Aescu, Amgen, Biogen, Berlin Chemie, Celgene, GSK, Hexal, Mylan, Novartis, Pfizer, UCB

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Deep sedation versus minimal sedation during endobronchial ultrasound transbronchial needle aspiration

Monaldi Archives for Chest Disease ◽

10.4081/monaldi.2018.967 ◽

2018 ◽

Vol 88 (3) ◽

Cited By ~ 3

Author(s):

Sergio C. Conte ◽

Giulia Spagnol ◽

Marco Confalonieri ◽

Beatrice Brizi

Keyword(s):

Diagnostic Accuracy ◽

Deep Sedation ◽

Correct Diagnosis ◽

Needle Aspiration ◽

Endobronchial Ultrasound ◽

Multicenter Studies ◽

Transbronchial Needle Aspiration ◽

Patient Tolerance ◽

Procedural Time ◽

Comparable Accuracy

The sedation plays an important role in the endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) procedure. The sedation can be Minimal (anxiolysis), Moderate (conscious sedation) or Deep. The ACCP guidelines suggest that moderate or deep sedation (DS) is an acceptable approach. In fact, several studies compare moderate versus deep sedation, but no study has been carried out to compare deep sedation versus minimal. We carried out a retrospective study to compare the Deep versus Minimal sedation (MiS) in patients undergoing EBUS-TBNA. The primary end point was the diagnostic accuracy. The secondary end points were adequacy and sensitivity. We evaluated the LN size sampling, procedural time, complications and patient tolerance. Thirty-six patients underwent EBUS-TBNA, 16 under DS and 20 under MiS. The overall diagnostic accuracy for correct diagnosis was 92.9% in DS group and 94.1% in MiS group (p=0.554). Sample adequacy, defined as the percentage of patients with a specific diagnosis by EBUS-TBNA, was 87.5% (14 of 16) and 85% (17 of 20) for the DS group and MiS group, respectively, (p=0.788); the sensitivity was 92.9% in the DS group (95% CI, 73-100%) and 92.9% in the MiS group (95% CI, 77-100%) (p=0.463). There were no major complications in either group. Minor complications were 4 in MiS and 1 in DS (p=0.355). The patients in the MiS group recalled the procedure more often compared to the other group (p=0.041). The majority of the patients would agree to undergo the same procedure again in the future in both groups (p=0.766). In our experience EBUS-TBNA performed under MiS has comparable accuracy, adequacy, sensitivity, complications and patient satisfaction to DS, even if the sample was small. Future prospective multicenter studies are needed to confirm our results.

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CT Findings in General Practice Patients with Suspected Acute Sinusitis

Acta Radiologica ◽

10.1177/02841851960373p258 ◽

1996 ◽

Vol 37 (3P2) ◽

pp. 708-713 ◽

Cited By ~ 9

Author(s):

M. Lindbæk ◽

U. L.-H. Johnsen ◽

E. Kaastad ◽

S. Dølvik ◽

P. Møll ◽

...

Keyword(s):

General Practice ◽

Clinical Diagnosis ◽

Interobserver Agreement ◽

Acute Sinusitis ◽

Fluid Level ◽

Ct Findings ◽

Kappa Value ◽

Ct Evaluation ◽

Common Combination ◽

Maxillary Sinuses

Purpose: To study CT findings in general practice patients with a clinical diagnosis of acute sinusitis, and to examine the interobserver variation between 2 radiologists with regard to their CT evaluation. Material and Methods: Two hundred and one patients were examined with coronal CT images of the paranasal sinuses within 2 days of the clinical diagnosis. Patients with chronic sinusitis were excluded. Fluid level or total opacification of any sinus were used as evidence of sinusitis. Results: One hundred and twenty-seven (63%) patients had fluid level or total opacification in a sinus region, most in more than one region. One hundred and fifteen had CT signs of sinusitis in the ethmoid region, 84 in the maxillary, 18 in the frontal, and 10 in the sphenoid. Forty-nine patients had a negative CT. In the evaluation of interobserver agreement, the overall assessment of the CT yielded a kappa value of 0.70. Conclusion: The study demonstrated great variation in the CT findings in general practice patients with suspected acute sinusitis. More than one sinus region was affected in most patients in whom sinusitis was confirmed by CT imaging; the most common combination was ethmoid and maxillary sinuses. The interobserver agreement was substantial.

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Accuracy of MRI in the Differential Diagnosis of Wilms Tumor

10.53350/pjmhs211582057 ◽

2021 ◽

Vol 15 (8) ◽

pp. 2057-2059

Author(s):

Maham Ashraf ◽

Aysha Anjum ◽

Eisha Tahir ◽

Amber Goraya ◽

Rabia Aqeel

Keyword(s):

Differential Diagnosis ◽

Diagnostic Accuracy ◽

Gold Standard ◽

Wilms Tumor ◽

Correct Diagnosis ◽

Renal Tumors ◽

Common Finding ◽

Predictive Values ◽

Female Ratio ◽

Male Predominance

Background & Objective: Renal tumors are a common finding in diagnostic imaging; these lesions usually are solid or cystic, benign or malignant, and the correct diagnosis may be difficult. The current study aims at to determine the diagnostic accuracy of magnetic resonance imaging for the diagnosis of Wilms tumor taking histopathology as gold standard. Methodology: This cross-sectional study was carried at the Department of Radiology, The Children’s Hospital & Institute of Child Health Lahore over 6 months from March 2019 to September 2019. The study involved 125 children of both genders aged between 2 years to 14 years presenting with a neoplastic mass in the retroperitoneum on ultrasound abdomen during initial workup. These children were assessed on MRI for the diagnosis of Wilms tumor. Later the diagnosis was confirmed on histopathology which was taken as gold standard and the diagnosis of MRI was judged accordingly as true/false and positive/negative. A written informed consent was obtained from every patient. Results: The mean age of the children was 5.8±3.9 years having a male predominance with male to female ratio of 1.8:1. Wilms tumor was suspected in 13 (10.4%) children on MRI. The diagnosis of Wilms tumor was confirmed in 13 (10.4%) children on histopathology. MRI was found to be 76.9% sensitive, 97.3% specific and 95.2% accurate with positive and negative predictive values of 76.9% and 97.3% respectively. Conclusion: In the present study, MRI was found to be 95.2% accurate in the differential diagnosis of Wilms tumor in children presenting with retroperitoneal mass which along with its non-invasive and radiation free nature advocates the preferred use of MRI in the diagnostic evaluation of such children in future oncologic practice. Keywords: Retroperitoneal Tumor, Wilms Tumor, MRI, Diagnostic Accuracy

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Is fibroid location associated with hemorrhage and complication rates following laparoscopic myomectomy?

10.21203/rs.3.rs-20868/v1 ◽

2020 ◽

Author(s):

Kiper Aslan ◽

Adnan Orhan ◽

Engin Turkgeldi ◽

Ebru Suer ◽

Nergis Duzok ◽

...

Keyword(s):

Posterior Wall ◽

Anterior Wall ◽

Uterine Wall ◽

Laparoscopic Myomectomy ◽

Complication Rates ◽

Analgesic Requirement ◽

Hospitalization Period ◽

Before And After ◽

Wall Groups ◽

Type 3

Abstract Objective To determine whether hemorrhage and complication rates vary according location of the dominant fibroid following laparoscopic myomectomy. Background Laparoscopic myomectomy is associated with less postoperative pain, analgesic requirement, shorter hospitalization period, and less febrile complications when compared to conventional laparotomy. Despite the advantages, complications like hemorrhage, blood transfusion, bowel and urinary tract injury and conversion to laparotomy may be seen in laparoscopic myomectomy. We don’t know whether fibroid location effect these complications. Materials & Methods Women, who underwent laparoscopic myomectomy at two different tertiary academic hospitals, were analyzed retrospectively. Only women with at least one intramural fibroid (Monroe type 3, 4 or 5) were included. Patients were categorized according to localization of the dominant fibroid, i.e. anterior uterine wall, posterior uterine wall, and fundus. Change in hemoglobin levels before and after surgery, and complication rates were compared across categories. Results 219 women with mean age of 35.7 +/-6 years were included. There were 81 women with fundal fibroid, 56 with anterior wall, and 72 with posterior wall fibroid. Other 10 women with intraligamentary and isthmic fibroid were excluded. The mean fibroid diameter was 6.7 ± 2.6, 6.6 ± 2.3, and 6.7 ± 2.3 cm in the fundal, anterior and posterior groups, respectively (p=0.9). The median (25 th – 75 th percentile) changes in hemoglobin levels were 1.5 (0.8 – 2.2), 1.3 (0.6 – 2.1), and 1.3 (0.9 – 2) g/dl in fundal, anterior and posterior wall groups, respectively (p = 0.55). There were 5 (6.2%), 5 (8.9%), and 2 (2.8%) complications in fundal, anterior, and posterior wall groups, respectively (p = 0.33). Conclusion Incidence of hemorrhage or complication does not seem to vary depending on fibroid location. However, the sample size was limited, the observed values suggest that fibroid location does not affect hemorrhage and complication rates.

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A Novel Model Based on Deep Convolutional Neural Network Improves Diagnostic Accuracy of Intramucosal Gastric Cancer (With Video)

Frontiers in Oncology ◽

10.3389/fonc.2021.622827 ◽

2021 ◽

Vol 11 ◽

Author(s):

Dehua Tang ◽

Jie Zhou ◽

Lei Wang ◽

Muhan Ni ◽

Min Chen ◽

...

Keyword(s):

Gastric Cancer ◽

Diagnostic Accuracy ◽

Diagnostic Performance ◽

Training Dataset ◽

Deep Convolutional Neural Networks ◽

Testing Dataset ◽

Kappa Value ◽

The Mean ◽

Gastric Cancer Patients ◽

Novel Model

Background and AimsPrediction of intramucosal gastric cancer (GC) is a big challenge. It is not clear whether artificial intelligence could assist endoscopists in the diagnosis.MethodsA deep convolutional neural networks (DCNN) model was developed via retrospectively collected 3407 endoscopic images from 666 gastric cancer patients from two Endoscopy Centers (training dataset). The DCNN model’s performance was tested with 228 images from 62 independent patients (testing dataset). The endoscopists evaluated the image and video testing dataset with or without the DCNN model’s assistance, respectively. Endoscopists’ diagnostic performance was compared with or without the DCNN model’s assistance and investigated the effects of assistance using correlations and linear regression analyses.ResultsThe DCNN model discriminated intramucosal GC from advanced GC with an AUC of 0.942 (95% CI, 0.915–0.970), a sensitivity of 90.5% (95% CI, 84.1%–95.4%), and a specificity of 85.3% (95% CI, 77.1%–90.9%) in the testing dataset. The diagnostic performance of novice endoscopists was comparable to those of expert endoscopists with the DCNN model’s assistance (accuracy: 84.6% vs. 85.5%, sensitivity: 85.7% vs. 87.4%, specificity: 83.3% vs. 83.0%). The mean pairwise kappa value of endoscopists was increased significantly with the DCNN model’s assistance (0.430–0.629 vs. 0.660–0.861). The diagnostic duration reduced considerably with the assistance of the DCNN model from 4.35s to 3.01s. The correlation between the perseverance of effort and diagnostic accuracy of endoscopists was diminished using the DCNN model (r: 0.470 vs. 0.076).ConclusionsAn AI-assisted system was established and found useful for novice endoscopists to achieve comparable diagnostic performance with experts.

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Acute respiratory failure as presentation of late-onset Pompe disease complicating the diagnostic process as a labyrinth: a case report

Multidisciplinary Respiratory Medicine ◽

10.4081/mrm.2018.176 ◽

2018 ◽

Vol 13 ◽

Author(s):

Francesco Menzella ◽

Luca Codeluppi ◽

Mirco Lusuardi ◽

Carla Galeone ◽

Franco Valzania ◽

...

Keyword(s):

Case Report ◽

Respiratory Failure ◽

Acute Respiratory Failure ◽

Pompe Disease ◽

Late Onset ◽

Correct Diagnosis ◽

Ventilatory Support ◽

Diagnostic Process ◽

Caucasian Woman ◽

Enzyme Replacement

Background: Acute respiratory failure can be triggered by several causes, either of pulmonary or extra-pulmonary origin. Pompe disease, or type II glycogen storage disease, is a serious and often fatal disorder, due to a pathological accumulation of glycogen caused by a defective activiy of acid α-glucosidase (acid maltase), a lysosomal enzyme involved in glycogen degradation. The prevalence of the disease is estimated between 1 in 40,000 to 1 in 300,000 subjects. Case presentation: This case report describes a difficult diagnosis of late-onset Pompe disease (LOPD) in a 52 year old Caucasian woman with acute respiratory failure requiring orotracheal intubation and subsequent tracheostomy for long-term mechanical ventilation 24 h/day. Despite a complex diagnostic process including several blood tests, bronchoscopy with BAL, chest CT, brain NMR, electromyographies, only a muscle biopsy allowed to reach the correct diagnosis. Discussion: The most frequent presentation of myopathies, including LOPD, is proximal limb muscle weakness. Respiratory related symptoms (dyspnea on effort, reduced physical capacity, recurrent infections, etc.) and respiratory failure are often evident in the later stages of the diseases, but they have been rarely described as the onset symptoms in LOPD. In our case, a third stage LOPD, the cooperation between pulmonologists and neurologists was crucial in reaching a correct diagnosis despite a very complex clinical scenario due to different confounding co-morbidities as potential causes of respiratory failure and an atypical presentation. In this patient, enzyme replacement therapy with infusion of alglucosidase alfa was associated with progressive reduction of ventilatory support to night hours, and recovery of autonomous walking.

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Rare Occurrence of Inhibitors in Von Willebrand Disease: A Case Report

Frontiers in Medicine ◽

10.3389/fmed.2021.807664 ◽

2022 ◽

Vol 8 ◽

Author(s):

Bipin P. Kulkarni ◽

Kirti Ghargi ◽

Chandrakala Shanmukhaiah ◽

Shrimati D. Shetty

Keyword(s):

Correct Diagnosis ◽

Severe Form ◽

Von Willebrand Disease ◽

Rare Occurrence ◽

Standard Assay ◽

Type 3 ◽

Von Willebrand ◽

High Degree ◽

Willebrand Factor ◽

Inhibitor Titer

Introduction: Type 3 Von Willebrand Disease (VWD) is the least common but the most severe form of a disease, with a prevalence of about 0. 5 to 1 per million in Western countries. The prevalence of type 3 VWD in the developing countries, with a high degree of consanguinity, is about 6 per million. Moreover, due to underdiagnosis of the milder cases, the prevalence of type 3 VWD is about 50% of the cases. Rarely, some patients develop the Von Willebrand Factor (VWF) inhibitors, which may subsequently develop severe anaphylactic reactions on further exposure to the VWF containing factor replacement therapy. The prevalence of inhibitor development in patients with type 3 VWD has been shown to be in the range of 5.8 to 9.5%. In the absence of a gold standard assay for the quantitation of VWF inhibitors, a correct diagnosis and management of these patients are often challenging.Objectives: The objective of this study is to standardize the Bethesda assay for the VWF inhibitors and to estimate the VWD inhibitor titer in two cases of congenital type 3 VWD, which developed the VWF inhibitors.Results and Conclusions: We could successfully standardize the Bethesda assay for the quantitation of VWF inhibitors in two patients with congenital type 3 VWD with inhibitors.

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