Rate Of False-negative Diagnoses Research Articles

Usefulness of bioelectrical impedance analysis in multiple sclerosis patients-the interrelationship to the body mass index.

Patients with multiple sclerosis (MS) have many potential factors (disease duration, spasticity, immobilization, or glucocorticoid use) that can deteriorate their nutritional status and impact both the progression and prognosis of the disease. Body mass index (BMI), the most widely used nutritional status assessment tool, has important limitations because it does not provide any data on body composition. This study aimed to assess the interrelationship between nutritional status assessment by both body mass index (BMI) and body composition using bioelectrical impedance analysis (BIA) and the consistency of diagnosis for underweight/underfat, normal weight/healthy, overweight/overfat, and obesity/obese MS patients. Anthropometric [BMI and waist-to-height ratio (WHtR)] and body composition (BIA) data were evaluated in 176 patients with MS. Patients were categorized into four nutritional status subgroups (underweight, normal weight, overweight, obese according to BMI, and underfat, healthy, overfat, and obese according to fat mass% by BIA). The median Expanded Disability Status Scale score was 4.5. Patients were then divided according to EDSS score as mild (EDSS 1.0-4.0) or moderate (EDSS 4.5-6.5) disability subgroups. Based on BIA assessment, there was a significantly higher prevalence of overfat than of overweight based on BMI [n = 50 (28.41%) vs. n = 38 (21.59%); p < 0.05]. However, the prevalence of obesity did not differ significantly regardless of the mode of diagnosis and was not significantly lower when assessed using BIA [n = 26 (14.77%) vs. n = 30 (17.05%), respectively]. The overall compatibility rates (CR) of diagnoses made using both BMI and BIA were 75.6, 77.0, and 70.1% for all patients with MS and the mild and moderate subgroups, respectively. The lowest CR was observed in the overweight group. Adiposity significantly underestimated BMI in all subgroups. In the moderate MS subgroup, BMI significantly overcategorized patients with MS as having a normal weight (p < 0.05). Stratification for abdominal obesity (WHtR > 0.5) showed that BMI significantly underestimated the prevalence of MS in overweight and obese vs. overfat and obese patients, as assessed using BIA (60.5 vs. 67%; p < 0.05). Clinical status (EDSS and ΔEDSS) was more closely related to the nutritional status categorized by FAT% assessed using BIA than using BMI cutoff points. However, the relationship was not statistically significant. Using the BMI cutoff point for nutritional status assessment in patients with MS is associated with a significant underestimation of excess fat mass. BIA-based FAT% based on BIA have a better relationship with abdominal obesity and disability status than with BMI in patients with MS. The highest rate of false-negative diagnoses was based on the BMI in patients with MS and moderate disability. Adiposity assessment using BIA appears to be a useful method for proper nutritional status assessment in the patients group.

Colposcopically Directed Biopsy Before Ablative Treatment Versus Direct Ablative Treatment in Patients With Cervical Oncogenic HPV.

In the past, the standard of care for women with abnormal cervical cytology has been the performance of colposcopically guided biopsy, followed by conization or large loop excision of the transition zone (LLETZ) where biopsy revealed pre-cancerous or cancerous areas. More straightforward protocols are emerging which advocate performing LLETZ in all women with highly suspicious cytology, suspicious colposcopic impression, or the presence of high-risk oncogenic human papilloma virus (HPV) strains in their cervical swabs. This, theoretically, would reduce the rate of false-negative diagnoses, but at the price of overtreating a significant number of healthy women. We retrospectively analyzed cervical cancer screening protocols in two large cohorts of women with high-risk HPV. The study compared outcomes between patients undergoing a colposcopically directed biopsy before LLETZ (n=683) and those proceeding directly to LLETZ without a biopsy (n=136). The primary focus was to assess whether intervening biopsies would reduce unnecessary ablative procedures without compromising the detection of high-grade lesions. The biopsy group had a high false-negative rate, with several high-grade lesions (CIN3) and a case of invasive cancer initially underdiagnosed. Conversely, the direct-to-LLETZ approach, while ensuring no high-grade lesions were missed, led to overtreatment of lower grade lesions. These findings raise concern about the reliance on biopsy results for treatment decisions. Neither protocol was entirely satisfactory, although the more aggressive one avoided the potentially life-threatening consequence of false-negative results. Further research is mandatory to accurately diagnose all cases requiring aggressive treatment, without subjecting healthy women to ablative treatments they do not need.

Evaluation of Convolutional Neural Network Architecture for Feasibility Analysis on Fetal Abdomen and Brain Images

This research aims to evaluate the possibilities of fetus ultrasound image classification using machine learning algorithms as normal or abnormal. Most of the earlier research works have produced a high percentage of false-negative classification results—recent research work aimed to reduce the rate of false-negative diagnoses. Also, the number of sonologists for analyzing prenatal ultrasound worldwide is very less and solved by developing an efficient algorithm, which reduces the percentage of false negatives in the diagnosis output. Several earlier research works focused on analyzing fetal abdominal image or fetal head images, making the medical industry use two different diagnostic modules separately. This work aims to design and implement a convolution frame-work named as two Convolution Neural Network (tCNN) model for diagnosing any fetal images. The proposed tCNN model diagnoses the fetal abdominal and fetal brain images and classify them as normal or abnormal. CNN1of tCNN performs segmentation and classification based on the acceptance of abdomen circumference and stomach bubble, umbilical vein, and amniotic fluid measurements. CNN2shows based on head circumference and head and abdominal circumference, femur, crown-rump, and humerus lengths measured.With clinical validation, an extensive experiment carried out and the results compared with the experts in terms of segmentation accuracy and the obstetric measurements. This paper provides a foundation for future multi-classification research works on diagnosing fetal intracranial abnormalities and differential diagnosis using machine learning algorithms.

High Rate of False Negative Diagnosis of Silent Patent Ductus Arteriosus on the Chest CT with 3 mm Slice-Thickness, Suggesting the Need for Analysis with Thinner Slice Thickness.

The purpose of this study was to evaluate the diagnostic accuracy of patent with ductus arteriosus (PDA) based on the availability of pretest information on routine chest CT with 3 mm slice-thickness. We retrospectively evaluated CT of 64 patients with PDA. The enrolled patients were categorized as group 1 (presence of pretest information) and 2 (absence of pretest information, silent PDA). CTs were read by eleven board-certified radiologists, and subsequently by two blind readers. We investigated whether a PDA was mentioned on the initial CT reading. Correct diagnosis of PDA was made in all patients with group 1 (n = 42). In contrast, only 13.7% were correctly diagnosed in group 2. All cases of missed PDA in group 2 were also missed by two blind readers. It is important to realize that the diagnostic accuracy of silent PDA is poor on the chest CT with 3 mm slice-thickness. Thus, use of axial CT images with the thinnest slice-thickness and multi-planar reformatted images (i.e., sagittal and coronal images) may be one way to reduce the number of missed PDA.

Nanozyme chemiluminescence paper test for rapid and sensitive detection of SARS-CoV-2 antigen

COVID-19 has evolved into a global pandemic. Early and rapid detection is crucial to control of the SARS-CoV-2 transmission. While representing the gold standard for early diagnosis, nucleic acid tests for SARS-CoV-2 are often complicated and time-consuming. Serological rapid antibody tests are characterized by high rates of false-negative diagnoses, especially during early infection. Here, we developed a novel nanozyme-based chemiluminescence paper assay for rapid and sensitive detection of SARS-CoV-2 spike antigen, which integrates nanozyme and enzymatic chemiluminescence immunoassay with the lateral flow strip. The core of our paper test is a robust Co–Fe@hemin-peroxidase nanozyme that catalyzes chemiluminescence comparable with natural peroxidase HRP and thus amplifies immune reaction signal. The detection limit for recombinant spike antigen of SARS-CoV-2 was 0.1 ng/mL, with a linear range of 0.2-100 ng/mL. Moreover, the sensitivity of test for pseudovirus could reach 360 TCID50/mL, which was comparable with ELISA method. The strip recognized SARS-CoV-2 antigen specifically, and there was no cross reaction with other coronaviruses or influenza A subtypes. This testing can be completed within 16 min, much shorter compared to the usual 1-2 h required for currently used nucleic acid tests. Furthermore, signal detection is feasible using the camera of a standard smartphone. Ingredients for nanozyme synthesis are simple and readily available, considerably lowering the overall cost. In conclusion, our paper test provides a high-sensitive point-of-care testing (POCT) approach for SARS-CoV-2 antigen detection, which should greatly facilitate early screening of SARS-CoV-2 infections, and considerably lower the financial burden on national healthcare resources.

Ultrasonographic soft markers for detection of rectosigmoid deep endometriosis.

The aim of this study was to evaluate the use of ultrasound (US) soft markers as a first-line imaging tool to raise suspicion of rectosigmoid (RS) involvement in women suspected of having deep endometriosis. We included in this prospective observational study all patients with clinical suspicion of deep endometriosis who underwent diagnostic transvaginal US evaluation at our unit from January 2016 to February 2017. Several US soft markers were evaluated for prediction of RS involvement (presence of US signs of uterine adenomyosis, presence of an endometrioma, adhesion of the ovary to the uterus (reduced ovarian mobility), presence of 'kissing ovaries' (KO) and absence of the 'sliding sign'), using as the gold standard expert US examination for the presence of RS endometriosis. Included were 333 patients with clinical suspicion of deep endometriosis. Of these, 106 had an US diagnosis of RS endometriosis by an expert. The only significant variables found in the prediction model were absence of the sliding sign (odds ratio (OR), 13.95; 95% CI, 7.7-25.3), presence of KO (OR, 22.5; 95% CI, 4.1-124.0) and the interaction between these two variables (OR, 0.03; 95% CI, 0.004-0.28). Regarding their interaction, RS endometriosis was present when KO was absent and the sliding sign was present in 10% (19/190) of cases, when both KO and the sliding sign were present in 71.4% (5/7) of cases, when both KO and the sliding sign were absent in 60.8% (76/125) of cases and when KO was present and the sliding sign was absent in 54.5% (6/11) of cases. Thus, when the sliding sign was absent and/or KO was present, transvaginal US showed a specificity of 75% (95% CI, 69-80%) and a sensitivity of 82% (95% CI, 73-88%). US findings of absence of the sliding sign and/or presence of KO in patients with clinical suspicion of endometriosis should raise suspicion of RS involvement and indicate referral for expert US examination, with a low rate of false-negative diagnosis. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Fine-needle aspiration cytology of nodular thyroid lesions: A 1-year experience of the thyroid cytopathology in a large regional and a University Hospital, with histological correlation

Background: Fine-needle aspiration cytology (FNAC) plays an important role in evaluation of nodular thyroid lesions and in planning appropriate management. Aim: the aim of the study is to reinterpret the FNAC diagnosis using the new 2017 Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) and explore its utility and to review the accuracy by correlating with histopathology and analyze the distribution of thyroid lesions. Settings and Design: A retrospective study for a period of 1 year will be undertaken, and all the cases of thyroid FNAC during the study period will be included in the study. Materials and Methods: All FNACs of the thyroid, which were done during the year 2011, were retrieved. The results of adequate FNAC samples were correlated with the histological diagnoses in 50 cases. Statistical Analysis: the statistical analysis was performed using MedCalc Statistical Software Results: About 592 cases were included in the study, after recategorization according to the TBSRTC, Bethesda I – 2 cases (0.33%), Bethesda II – 473 cases (79.8%), Bethesda III – 54 cases (9.1%), Bethesda IV – 23 cases (3.8%), Bethesda V – 3 cases (0.5%), and Bethesda VI – 37 cases (6.25%). The false-negative rate is 9%, accuracy rate is 91%, and rate of malignancy in atypical lesions is 53.3%, with overall rate of accuracy of 61.5%. The incidence of microcarcinoma was 4/50 (8%). Conclusions: The distribution of thyroid lesions in our institute is similar to that seen elsewhere. The rate of malignancy in indeterminate lesions was 33.33%. FNA has a low false-negative rate for diagnosis of thyroid malignancy; however, controversy exists regarding the accuracy of FNA for nodules smaller than 1 cm. The nomenclature change of follicular variant of papillary thyroid carcinoma to noninvasive follicular thyroid neoplasm with papillary-like nuclear features has led to necessary changes in definitions of various categories in 2017 TBSRTC as well and is discussed in this paper.

Diagnostic Value of Technetium-99m Bone Scintigraphy in the Detection of Cervical Spine Metastases in Oncological Patients.

A retrospective cohort, radiographic study. To assess the diagnostic accuracy of bone scintigraphy (BS) for the detection of cervical spine metastases in oncological patients. BS remains the modality of choice for the screening of bone metastases, because of its feasibility in whole-body scanning and its widespread availability at low cost. Current practice guidelines for patients with malignant diseases recommend BS imaging as the primary screening method for detecting both axial and appendicular skeletal metastases. Of 481 patients, 242 were diagnosed with cervical spinal metastases from a primary cancer. The BS findings of these patients, evaluated by nuclear medicine physicians, were assessed with respect to their usefulness for detecting cervical spine metastases. Magnetic resonance imaging findings, evaluated by radiologists, were used as the reference standards. The diagnostic value of BS was compared between subgroups according to the order in which the diagnostic procedures (magnetic resonance imaging and BS) were completed, the presence of pathological fractures, the location of the primary malignancy, and the number of cervical metastases. The sensitivity of BS in the detection of cervical spine metastases was 59.1%, with a 40.9% rate of false-negative diagnoses; the specificity was 94.6%, with a 5.4% rate of false-positive diagnoses. The sensitivity tended to be higher in the presence of pathological fractures (72.1% in cases with a fracture vs. 3% in cases without a fracture) and a greater number of lesions (r = 0.921). Neither the order in which the diagnostic examinations were performed nor the location of the primary cancer, except for those in the stomach and liver, appeared to affect the diagnostic accuracy of BS. Considering the moderately high false-negative diagnostic rate obtained in the present study, BS alone cannot accurately diagnose metastases in the cervical spine in oncological patients. 3.

Determining the impact of psychosis on rates of false-positive and false-negative diagnosis in Alzheimer's disease

IntroductionThe rate of clinical misdiagnosis of Alzheimer's disease (AD) and how psychosis impacts that clinical judgment is unclear. MethodsUsing data from National Alzheimer's Coordinating Center, we compared the clinical and neuropathologic diagnosis in patients with a diagnosis of AD with autopsy and in neuropathology-confirmed AD cases (n = 961). We determined the rate of true positives, false positives, and false negatives in patients with and without psychosis. ResultsA total of 76% received a correct AD diagnosis, 11.9% had a false-negative diagnosis, and 12.1% had a false-positive diagnosis of AD. Psychotic patients had a higher rate of false-negative diagnosis and a lower rate of false-positive diagnosis of AD compared with nonpsychotic patients. DiscussionPatients with psychosis were five times more likely to be misdiagnosed as dementia with Lewy bodies, whereas patients without psychosis were more likely to be falsely diagnosed with AD when vascular pathology is the underlying neuropathologic cause of dementia.

Do we need a change in ED diagnostic strategy for adult acute epiglottitis?

ObjectivesTo retrospectively evaluate the diagnostic performance of qualitative and quantitative radiographic parameters for diagnosing adult acute epiglottitis, and identify the prevalence and risk factors of false-negative neck radiography-based diagnosis of acute epiglottitis. MethodsAn emergency physician and a radiologist independently reviewed neck radiographs of 91 patients with laryngoscopy-confirmed acute epiglottitis and 91 control subjects between March 2010 and June 2016 for qualitative and quantitative radiographic parameters of acute epiglottitis, and concluded a diagnosis. Receiver operating characteristic (ROC) curves were constructed to assess the diagnostic performance of radiographic parameters, while independent risk factors of false-negative diagnosis were determined by multivariate logistic regression analysis. Inter-observer agreement was also calculated. ResultsAll radiographic parameters showed good diagnostic performance with sensitivities and specificities of 33.0–80.2% and 64.8–100%, respectively. Epiglottis width (EW)>6.3mm showed the highest diagnostic performance (area under the ROC curve [AUC]: 0.867, sensitivity: 75.8%, specificity: 97.8%). Interobserver agreement for all radiographic parameters was excellent (range: 0.893–0.991). The lateral neck radiography-based false-negative diagnosis rate was 31.9%, and previous oral antibiotic usage was an independent risk factor of false-negative results. ConclusionEW>6.3mm showed the best diagnostic accuracy, facilitating a neck radiograph-based diagnosis of acute epiglottitis. However, false-negative results on neck radiograph are quite common and previous oral antibiotic usage is a risk factor. Based on the knowledge of the usefulness and risk factors of false-negative results of neck radiography, diagnostic process for acute epiglottitis using neck radiography need to be changed.

Ampullectomy versus pancreaticoduodenectomy for ampullary tumors

BackgroundConsiderable controversy surrounds the treatment of ampullary neoplasms. This report describes the authors' experiences regarding the choice of either ampullectomy or pancreaticoduodenectomy for treatment of ampullary tumors. MethodsDemographics, statistical findings concerning diagnosis, surgical risks including morbidity and mortality, and outcomes were evaluated and compared between the ampullectomy and pancreaticoduodenectomy groups for ampullary tumors retrieved from a prospectively collected computer database of 992 periampullary tumors resected during the period from 1965 to 2013. ResultsA total of 377 patients with ampullary tumors were included; 15 underwent ampullectomy and 362 underwent pancreaticoduodenectomy. The overall false-negative rate for diagnosis of ampullary malignancy was 11.2%, specificity was 50.0%, positive predictive value was 98.3%, negative predictive value was 12.2%, and the overall accuracy was 87.6% (77.5% by preoperative endoscopic biopsy and 83.9% by intraoperative frozen-section biopsy). Ampullectomy was associated with shorter postoperative stays and lower surgical morbidity. There was no statistical difference observed between the two groups regarding surgical mortality, pancreatic leakage, or gastric atonia. The tumor recurrence rate was lower after pancreaticoduodenectomy, but the difference between the groups was not significant. Overall, there was no difference in survival observed between the two groups. ConclusionBecause biopsy is not routinely reliable, pancreaticoduodenectomy is preferable to ampullectomy for an ampullary tumor of uncertain diagnosis. Ampullectomy is associated with lower surgical morbidity and should therefore remain in the armamentarium of the pancreatic surgeon when comorbidity precludes major surgery.

Diagnostic Accuracy of C-Reactive Protein for Periprosthetic Joint Infection: A Meta-Analysis

We conducted a study to assess the diagnostic accuracy of the C-reactive protein (CRP) assay for periprosthetic joint infection (PJI). For the purpose of the study, we conducted a search of PubMed, selecting only studies that described the diagnosis of PJI through measurement of the serum CRP concentration. The results were meta-analyzed by pooling estimates of sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR-), and diagnostic odds ratio (DOR) and constructing respective summary receiver-operating characteristic (SROC) curves. We also conducted subgroup analyses according to cutoff values of the serum CTP concentration. A total of 25 studies met the selection criteria for inclusion in the analysis. The pooled estimates for sensitivity, specificity, and the area under the curve (AUC) for the CRP assay were 0.82 (95% CI 0.80-0.84), 0.77 (95% CI 0.76-0.78), and 0.877±0.016, respectively. In the 10 mg/L cutoff subgroup, the pooled estimates for sensitivity, specificity, and the AUC were 0.881 (95% CI 0.859-0.901), 0.728 (95% CI 0.706-0.749), and 0.8496±0.0248, respectively. We found that the serum CRP assay had good diagnostic accuracy for PJI but that its specificity was low. We recommend that when the CRP assay yields a normal result, other tools be used adjunctively with it to reduce the rate of false-negative diagnoses of PJI.

The reasons of false negative results of endobronchial ultrasound-guided transbronchial needle aspiration in the diagnosis of intrapulmonary and mediastinal malignancy.

Although the sensitivity can reach 99%, endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has a significantly high false negative rate for diagnosis and staging of thoracic malignancy. We performed this retrospective study to investigate the causes of false negative results and to improve the efficacy and accuracy of EBUS-TBNA. We reviewed all patients suspected of intrapulmonary or mediastinal malignancy who undertook EBUS-TBNA between July 2009 and August 2012 in Chinese PLA general hospital. We retrieved the pathological results of EBUS-TBNA and video-assisted thoracic surgery (VATS) and follow-up data. The sensitivity, specificity, positive predictive value and negative predictive value were calculated. 185 patients were included in this study. Diagnosis of malignancy was established on 172 patients by EBUS-TBNA, and 8 patients with negative EBUS-TBNA result gained their final diagnosis of malignancy via VATS. The sensitivity, specificity, negative predictive value and accuracy for diagnosis of malignancy for EBUS-TBNA were 96%, 100%, 33% and 96% respectively. Inadequacy of the EBUS-TBNA specimens, internal necrosis in the lymph nodes and rare cancer types contributed to the false negative EBUS-TBNA results. VATS is obligatory to explain the negative results of EBUS-TBNA in patients suspected of malignancy.

Utilidad de la biopsia percutánea core guiada por tomografía computada (TC) en lesiones pulmonares: experiencia de 7 años

CT guided percutaneous biopsy of pulmonary lesions is a widely used technique. To evaluate the yield and complication rate of CT-guided percutaneous core biopsy of pulmonary lesions. A retrospective study of 153 consecutive lung biopsies performed in a 7-year period was undertaken. Patients and lesions characteristics were reviewed. The yield for the diagnosis of malignant and benign lesions and the complication rate were calculated. Lesion size and depth from the pleural surface were analyzed as potential predictive variables for occurrence of a false-negative diagnosis of malignancy. The final diagnosis was established by surgical biopsy of the lesion or clinical and imaging follow up. The mean age of patients was 66 ± 14 years and 55% were mole. The final diagnosis of the lesion was malignant in 139 and benign in 14 cases (prevalence of malignancy 90.8%). For the diagnosis of malignancy, the overall yield of the biopsy was 91.5%o with a sensitivity of 90.6%>. A specific diagnosis of benign lesions was obtained in 5 out of l4 biopsies (35%). We did not identify an association between the lesion size or depth and the rate of false-negative diagnosis of malignancy. The pneumothorax rate was 13.7%o (n = 21) and eight (38%) required drainage. The average lesion depth of patients that had a pneumothorax was significant greater than the cases without the complication. No major bleeding complications occurred. Percutaneous CT-guided cutting needle biopsies of pulmonary lesions have an excellent diagnostic accuracy for malignant pulmonary lesions, at a low complication rate.

Application of magnifying narrow-band imaging endoscopy for diagnosis of early gastric cancer and precancerous lesion

BackgroundGastric carcinoma is the second commonest cause of cancer deaths worldwide. Early detection and diagnosis of gastric cancer in the stomach is important for improving the prognosis of gastric cancer. This retrospective study was designed to investigate the value of magnifying narrow-band imaging (NBI) in the diagnosis of precancerous lesions and early gastric cancer.MethodsThis study included 122 patients who were diagnosed with early gastric cancer or precancerous gastric lesions by endoscopy. The patients underwent an examination with conventional endoscopy, magnifying NBI, and magnifying chromoendoscopy. Images resolution was evaluated, and the morphology, pit patterns and blood capillary forms of lesions were analyzed. The presence of gastric carcinoma and high grade intraepithelial neoplasia in the biopsy samples was considered as a positive pathological result, which is used to assess accuracy of endoscopic diagnosis.ResultsFor image resolution, magnifying NBI and magnifying chromoendoscopy were significantly superior to magnifying conventional endoscopy in morphology, pit pattern and blood capillary form (P < 0.01), and magnifying NBI was significantly superior to magnifying chromoendoscopy in blood capillary form (P < 0.01). IV, V1, and VI type of gastric pit pattern were detected in 14 cases, 43 cases, and 17 cases in patients with high grade intraepithelial neoplasia, respectively. V1 and VI type of gastric pit pattern were detected in 9 cases and 39 cases in patients with early gastric cancer, respectively. The presence of irregular minute vessels and variation in the caliber of vessels was found in 109 cases. The accuracy, sensitivity, specificity, false positive rate and false negative rate for diagnosis of early gastric cancer and precancerous gastric lesions were 68.9%, 95.1%, 63.1%, 24.5%, and 32.4% for conventional endoscopy, 93.6%, 92.7%, 94.5%, 5.7%, and 6.9% for magnifying NBI, and 91.3%, 88.6%, 93.2%, 13.2%, and 21.48% for magnifying chromoendoscopy, respectively.ConclusionsThis study demonstrates that magnifying NBI is superior to conventional endoscopy in the diagnosis of early gastric cancer and precancerous gastric lesions, and can be used for screening early malignancies of the stomach.

The Impact of Anxiety Disorders on Assessment of Myocardial Ischemia and Exercise Stress Test Performance

To evaluate the sensitivity of electrocardiogram (ECG) versus single photon emission computed tomography (SPECT) assessments of ischemia in patients with anxiety disorders (AD) and the extent to which patients exhibit poorer exercise performance, compared with patients without AD. Patients referred for nuclear exercise stress testing (N = 2271) underwent a structured psychiatric interview (PRIME-MD) to assess for AD. Exercise performance parameters were assessed during ECG treadmill testing, after which patients underwent SPECT imaging. Analyses revealed that patients with AD exhibited lower peak exercise systolic blood pressure and rate pressure product than patients without AD. When major depressive disorder was included as an additional covariate, the previous results became trends. Results also indicated a lower rate of electrically positive ecg tests and a higher rate of false-negative diagnoses of myocardial ischemia according to ecg among patients with AD. Including major depressive disorder as a covariate rendered the effects of ad nonsignificant. There was no evidence of reduced exercise performance in patients with AD. Findings suggest that AD may be associated with mild impairments in cardiovascular exercise reactivity and may also alter the detection of myocardial ischemia using ecg assessments in patients referred for exercise stress testing. However, the influence of AD appears to be moderated by comorbid depression. Results suggest that exercise test performance and detection of ischemia may be influenced by mood and/or anxiety disorders and that greater efforts should be made to include routine mood and/or anxiety disorder screening as part of exercise stress testing protocols.

Clinico-Pathological Discrepancies in the Diagnosis of Causes of Maternal Death in Sub-Saharan Africa: Retrospective Analysis

BackgroundMaternal mortality is a major public-health problem in developing countries. Extreme differences in maternal mortality rates between developed and developing countries indicate that most of these deaths are preventable. Most information on the causes of maternal death in these areas is based on clinical records and verbal autopsies. Clinical diagnostic errors may play a significant role in this problem and might also have major implications for the evaluation of current estimations of causes of maternal death.Methods and FindingsA retrospective analysis of clinico-pathologic correlation was carried out, using necropsy as the gold standard for diagnosis. All maternal autopsies (n = 139) during the period from October 2002 to December 2004 at the Maputo Central Hospital, Mozambique were included and major diagnostic discrepancies were analyzed (i.e., those involving the cause of death). Major diagnostic errors were detected in 56 (40.3%) maternal deaths. A high rate of false negative diagnoses was observed for infectious diseases, which showed sensitivities under 50%: HIV/AIDS-related conditions (33.3%), pyogenic bronchopneumonia (35.3%), pyogenic meningitis (40.0%), and puerperal septicemia (50.0%). Eclampsia, was the main source of false positive diagnoses, showing a low predictive positive value (42.9%).ConclusionsClinico-pathological discrepancies may have a significant impact on maternal mortality in sub-Saharan Africa and question the validity of reports based on clinical data or verbal autopsies. Increasing clinical awareness of the impact of obstetric and nonobstetric infections with their inclusion in the differential diagnosis, together with a thorough evaluation of cases clinically thought to be eclampsia, could have a significant impact on the reduction of maternal mortality.

Pitfalls in the cytodiagnosis of metastatic squamous cell carcinoma in the head and neck: A retrospective study

Background: Lateral neck swelling in an adult is a common presentation for primary and secondary malignant lesions. Metastasis from squamous cell carcinoma often leads to various secondary changes in the lymph nodes, which makes their diagnosis on cytology a difficult task. Sometimes, the primary sites remain occult and any false negative cytological diagnosis becomes a misleading factor. Aim: Our aim was to evaluate the efficacy of fine needle aspiration cytology (FNAC) in diagnosing metastasic squamous cell carcinoma in the head and neck, and to highlight the precautions that can reduce the rate of false negative diagnosis. Materials and Methods: Two thousand five hundred and twelve patients in an age range of 18 to 80 years and presenting with a solitary lateral swelling of the neck were selected for this study. Results: Three hundred and seventy positive and 45 suspicious cases of metastatic squamous cell carcinoma were detected by FNAC; there were 15 false negative cases. All of them were associated with cystic change, abscess, or necrosis. The primary sites for carcinoma were the tonsil, tongue, pharynx, and larynx. No primary site could be detected in three cases. Histopathological confirmation was done in all the cases. The specificity and sensitivity of FNAC in the detection of positive cases of metastatic squamous cell carcinoma were 96.05 and 96.5% respectively. Conclusions: Any lateral neck swelling in adult patients that is associated with cystic change, abscess, or necrosis on FNAC should be carefully searched for malignant cells. Clinical re-evaluation and image guided surgical biopsy should supplement FNAC in suspicious cases. In spite of the possible limitation of a false negative diagnosis, FNAC remains a useful tool in diagnosing metastasis with good certainty.

Magnetic resonance imaging – unravelling the mystery

Magnetic resonance imaging – unravelling the mystery

Highly Effective Detection of Human Papillomavirus 16 and 18 DNA by a Testing Algorithm Combining Broad-Spectrum and Type-Specific PCR

The use of a single broad-spectrum human papillomavirus (HPV) DNA-based PCR test may fail to detect lower concentrations of HPV DNA due to competition between different genotypes in mixed infections. To improve HPV detection by PCR, broad-spectrum and type-specific (TS) PCRs were combined, with a focus on HPV-16 and HPV-18. Cervical and cervicovaginal cell samples were obtained from 1,113 healthy women (age range, 15 to 25 years) participating in an HPV-16/HPV-18 candidate vaccine efficacy trial. These samples were tested by a broad-spectrum SPF(10) PCR-DNA enzyme immunoassay, followed by a primer SPF(10)-based line probe assay (SPF(10) LiPA), and HPV-16- and HPV-18-TS PCRs. The results for the majority of the HPV-16/18 SPF(10) LiPA-positive samples were confirmed by TS-PCR (kappa values, 0.775 for HPV-16 and 0.785 for HPV-18). However, TS PCR revealed additional positive samples among those that contained other HPV genotypes due to competition. Conversely, SPF(10) LiPA identified HPV-16 or -18 in samples that remained negative by TS PCR as a result of sampling variation. Analysis of follow-up samples from more than 1,000 women confirmed that the combination of SPF(10)-LiPA with additional HPV-16- and HPV-18-TS PCR diminishes the rate of false-negative diagnosis. The combination of broad-spectrum and TS PCRs resulted in a novel testing algorithm. This combination of assays is more accurate than either method alone, and the novel algorithm offers a highly accurate and effective method for the analysis of HPV infections.