scholarly journals Pheochromocytoma in Italy: a multicentric retrospective study

1999 ◽  
pp. 619-624 ◽  
Author(s):  
M Mannelli ◽  
L Ianni ◽  
A Cilotti ◽  
A Conti
Keyword(s):  
Clinical Laboratory ◽  
False Negative ◽  
Plasma Catecholamines ◽  
Adrenal Tumors ◽  
Screening Methods ◽  
Mibg Scintigraphy ◽  
Glucagon Test ◽  
Initial Symptoms ◽  
Basal Plasma ◽  
Surgical Data

OBJECTIVE: To conduct an epidemiological study on pheochromocytoma in Italy. METHODS: Data on 284 patients with pheochromocytoma observed between 1978 and 1997 were collected from 18 Italian centers through a questionnaire reporting epidemiological, clinical, laboratory, radiological and surgical data. RESULTS: 53.6% of the patients were females and 46.4% were males. Thirty-two tumors were discovered as incidental adrenal masses. The most frequent referred symptoms were palpitations (58.1%), headache (51.9%), sweating (48. 8%) and anxiety (35.3%). Their association was present only in 15.5% of patients. Paroxysmal symptoms were reported in 67.1% and hypertensive crises in 59.7% of patients. Normal blood pressure (systolic and diastolic) was present both in the supine and upright positions in 21.1% of patients. Among laboratory assays, urinary vanylmandelic acid (VMA) was the most widely used (58.1%) and was the least sensitive (25% of false negative results). Basal plasma catecholamines were found to be normal in 11.3% of patients but were always elevated when sampled during a hypertensive paroxysm. A clonidine suppression test was performed in 38 patients with no adverse side effects. It gave a false negative response in 2 patients. A glucagon test was performed in 21 patients. It was interrupted for acute hypertension in 52.4% of patients. Only 5/21 patients were normotensive and had normal basal plasma catecholamines. In these patients the test gave a positive response in four (80%). CT (79.6%) and I-MIBG scintigraphy (68.5%) were the most widely used methods for tumor localization. CT sensitivity was 98.9% for intra-adrenal and 90.9% for extra-adrenal tumors. MIBG sensitivity was 88.5%. In the 263 patients who underwent surgery, the tumor was intra-adrenal in 89.4%, extra-adrenal in 8.5%, intra- and extra-adrenal in 2.1%, and bilateral in 11.0% of patients. Malignancy was reported in 9.9% of cases. Surgery caused remission of hypertension in 59.3%, improvement in 26.8%, and no changes in 13. 9% of patients. In the last group the interval between initial symptoms and diagnosis was significantly longer. CONCLUSIONS: The present study confirms that the clinical presentation of pheochromocytoma is variable and aspecific. Normotension is often present and often the tumor is discovered incidentally. An indication for the routine use of screening methods more sensitive than urinary VMA is strongly suggested. The clonidine test was found to be safe and should be preferred to the glucagon test which has to be restricted to very selected patients. CT and MIBG scintigraphy are almost always successful in localizing the tumor. Reversal of hypertension by surgery seems to depend on an early diagnosis.

scholarly journals False iodine-131 MIBG scintigraphy findings in adrenal tumors: correlation with MR imaging

2020 ◽  
Author(s):  
Serena Dell’Aversana ◽  
Valeria Romeo ◽  
Roberta Assante ◽  
Michele Klain ◽  
Simone Maurea
Keyword(s):  
Mr Imaging ◽  
False Positive ◽  
False Negative ◽  
Tracer Uptake ◽  
Adrenal Tumors ◽  
Mibg Imaging ◽  
Mibg Scintigraphy ◽  
Tracer Concentration ◽  
Iodine 131 ◽  
Large Primary

AbstractIn this study, we report our experience regarding the occurrence of false radionuclide findings in adrenal iodine-131 MIBG scintigraphy. We present a total of five patients in which nuclear images were false negative or positive in three and two cases, respectively, according to the standard radionuclide established criteria. In particular, the three cases of false-negative MIBG images consisted of two patients with necrotic or cystic pheochromocytomas (Cases 1 and 3) and a patient with a small pheochromocytoma (Case 2); the two cases of false-positive MIBG imaging consisted of a patient with an adenoma showing intense tracer uptake and of a large primary necrotic carcinoma with heterogeneous tracer concentration.

scholarly journals Performance of the LARC classifier in clinical laboratories.

1976 ◽  
Vol 24 (1) ◽  
pp. 202-210 ◽  
Author(s):  
D A Cotter ◽  
B H Sage
Keyword(s):  
False Positive ◽  
Clinical Laboratory ◽  
False Negative ◽  
Performance Parameters ◽  
Clinical Laboratories ◽  
Normal Ranges ◽  
Abnormal Cells

As part of the installation procedure of the LARC leukocyte differential classifier in a clinical laboratory, a 100-slide protocol is carried out to establish the performance of the classifier in the laboratory. The detailed make-up of this protocol and its relationship to key performance parameters for the leukocyte differential are described in detail. Data from the first ten of these protocols are presented which establish the (a) normal ranges, (b) reproducibility, (c) accuracy, (d) false-positive/false-negative rates for the detection of left shifts and (e) false-positive/false-negative rates for the detection of bloods with abnormal cells.

EVALUATION OF PROPRANOLOL-GLUCAGON TEST

1977 ◽  
Vol 86 (2) ◽  
pp. 243-250 ◽  
Author(s):  
Y. Okada ◽  
K. Watanabe ◽  
T. Takeuchi ◽  
T. Hata ◽  
H. Mikam ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Body Weight ◽  
False Negative ◽  
Human Growth ◽  
Maximum Level ◽  
Normal Children ◽  
Provocative Test ◽  
Glucagon Test ◽  
Control Subjects ◽  
Stimulation Of

ABSTRACT A propranolol-glucagon test was evaluated in 24 control normal children, 21 pituitary dwarfs, 15 patients with constitutional short stature, 2 with chromosome aberration and 4 with miscellaneous diseases. The dose of glucagon enough for the stimulation of human growth hormone (HGH) secretion is more than 20 μg/kg of body weight. During the test in the control subjects the serum HGH level increased from 2.3 ± 1.2 ng/ml to a maximum level of 30.0 ± 15.1 ng/ml, when 10 mg propranolol, regardless of body weight and 30 μg glucagon per kg of body weight are given. The dose of propranolol administered ranged from 0.2 to 1.0 mg/kg of body weight in normal children studied. Serum 11-OHCS also increased significantly from 14.5 ± 11.2 μg/100 ml to 30.1 ± 15.5 μg/100 ml (P <0.01). There was no difference in the maximum level of urinary total catecholamines in propranolol-glucagon test between 7 pituitary dwarfs and 7 control subjects. The mechanism of HGH response to propranolol-glucagon administration is unknown, but propranolol-glucagon administration is a sensitive and reliable provocative test for HGH secretion, since false negative responses of HGH are not observed in patients with non-pituitary disease.

Evaluation of Two Field Screening Test Kits for the Detection of PCBs in Soil by Immunoassay

1994 ◽  
Vol 77 (6) ◽  
pp. 1664-1671 ◽  
Author(s):  
Larry C Waters ◽  
Rob R Smith ◽  
Joe H Stewart ◽  
Roger A Jenkins ◽  
Richard W Counts
Keyword(s):  
False Negative ◽  
Cost Effective ◽  
Effective Field ◽  
Screening Methods ◽  
Laboratory Methods ◽  
Rigorous Evaluation ◽  
Field Screening ◽  
Hazardous Waste Sites ◽  
The Cost ◽  
Antigen Antibody

Abstract Effective field screening methods could minimize the time and reduce the cost of characterizing and remediating hazardous waste sites. Rigorous evaluation of novel field screening methods is required before they can be considered as replacements for, or adjuncts to, currently used laboratory methods. Alternatives to standard laboratory analytical methods should be rapid, analyte-specific, cost-effective, accurate, and sensitive in the range at which the analyte is regulated. In this study, 2 immunoassay- based field test kits for polychlorinated biphenyls (PCBs) in soil were evaluated with reference to those criteria. PCBs were analyzed in both spiked and field soil samples. Based on laboratory performance, we estimate that 20 to 40 samples can be analyzed in the field per day. Sensitivity of the assay is in the 1 ppm range. Because the assay is based on the specificity of the antigen/antibody reaction, interferences are practically negligible. The method is accurate; the false-negative and false-positive results that were observed can be explained by differences in the immunoreactivities of the Aroclors present in the test samples and the Aroclors used as standards in the assay. The savings in time and expense to analyze PCBs in soil with the immunoassay-based test kits over conventional laboratory methods should be substantial.

scholarly journals High-Capacity Screening of Arylalkylamine N-Acetyltransferase Inhibitors using a High-Performance Liquid Chromatography System

2000 ◽  
Vol 5 (5) ◽  
pp. 361-368 ◽  
Author(s):  
Gilles Ferry ◽  
Jean A. Boutin
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Enzyme Inhibitor ◽  
False Negative ◽  
High Capacity ◽  
Screening Methods ◽  
Enzymatic System ◽  
Systematic Screening ◽  
Hplc System

Systematic screening is a natural development of any pharmacological program. Most enzyme inhibitor screens use indirect or "aspecific" methods, such as colorimetric or fluorimetric ones. These screening methods cause quite a few false-positive and false-negative hits. In order to limit these as much as possible, we developed a methodology using a high-performance liquid chromatography (HPLC) system for the medium throughput screening of serotonin N-acetyltransferase inhibitors. The core of this screening system is (1) the dramatic shortening of the analytical time down to 100 s per run by using a high-performance analytical column (Turbo), and (2) the use of absorption as opposed to radioactivity for detection of the product of the reaction (N-acetylserotonin). This system permits the analysis of about 1,000 compounds per day to be performed with a single HPLC system. This enzymatic system was taken as an example, because the methodology can be extended to many other enzymes, particularly transferases, phosphatases, and kinases.

Diagnostic value of cytokeratin-1, survivin and TG expression in circulating tumor cells in the differentiation of benign and malignant thyroid nodules.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e17575-e17575
Author(s):  
Jie Liu ◽  
Siyuan Xu ◽  
Jinghua Luo ◽  
Yan Wang ◽  
Xia Liu ◽  
...  
Keyword(s):  
Thyroid Cancer ◽  
Real Time ◽  
Quantitative Pcr ◽  
Thyroid Nodules ◽  
False Negative ◽  
False Negative Rate ◽  
Diagnostic Value ◽  
Screening Methods ◽  
Real Time Quantitative Pcr ◽  
Minimal Trauma

e17575 Background: Fine needle aspiration cytology (FNAB) has the advantages of minimal trauma, speed and accuracy, and is currently considered to be the most predictive screening technique before thyroid nodule surgery. However, there are several drawbacks to this method, including certain complications, a relatively high false negative rate, a low acceptance of invasive surgery among patients, and the fact that about 20% of the lesions cannot be clearly defined as benign or malignant. Blood-based noninvasive testing can be used to analyze circulating cancer cells (CTCs) for clinical testing. Here, we investigated the performance of CTCs in thyroid cancer screening. Methods: We established a multi-marker real-time quantitative PCR (CK-19/surviving/Tg) to detect and quantify CTCs in peripheral blood samples. 100 subjects who were diagnosed by ultrasound imaging as having thyroid nodules were enrolled. FNAB or surgical specimens were subjected to pathological tests to differentiate between the benign nodules and thyroid cancer. Meanwhile the CTCs in the blood were isolated and quantified by multi-marker qPCR. Results: Among 100 patients, 50 were diagnosed as Papillary Thyroid Carcinoma (PTC) by pathological test. The sensitivity of each single marker of CK19, Survivin and Tg were only 48%, 44%, and 50% respectively, with the specificity of 94%, 100% and 94%. However, the combination of these three markers results in the highest sensitivity and specificity of 86% and 90%. Thus, the combined marker could achieve the best diagnostic value. Conclusions: Compared with FNAB, CTC is minimally invasive. The performance of the multi-marker real-time quantitative PCR showed that CTC could be used as an adjunctive test after ultrasound evaluation. Our results indicated that CTCs have potential clinical value in the identification of benign and malignant thyroid nodules.

Targeted next generation sequencing to expand HER2 status detection: Implication for newer HER2-directed agents.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. 1047-1047
Author(s):  
Ning Liao ◽  
RongFeng Song ◽  
FangQin Xue ◽  
Shuirong Zhang ◽  
Samuel J Klempner ◽  
...  
Keyword(s):  
Clinical Laboratory ◽  
False Negative ◽  
High Sensitivity ◽  
Expression Level ◽  
Her2 Status ◽  
Genomic Alteration ◽  
Her2 Expression ◽  
Specificity And Sensitivity ◽  
Sensitivity Specificity ◽  
Erbb2 Amplification

1047 Background: Establishment of ERBB2 ( HER2) amplification status in breast carcinoma (BC) and gastric carcinoma (GC) is essential for treatment selection, but no anti- HER2 therapies have been approved for tumors with low level of HER2 expression. The clinical trial ( NCT02564900 ) was initiated to evaluate the safety and efficacy of trastuzumab deruxtecan (DS-8201a) in BC patients with lower HER2 expression by current methods. This study aims to validate NGS-based detection for HER2 low expression. Methods: 275 BC and 425 GC were collected and subjected to NGS for genomic alteration detection. The testing was carried out by a College of American Pathologists (CAP) accredited and Clinical Laboratory Improvement Amendments (CLIA) certified laboratory, Shanghai, China. Protein expression was analyzed by using IHC. FISH was carried out on 108 samples, including 63 BC and 45 GC. To set up NGS cutoff, FISH was performed on additional 34 samples. Sensitivity, specificity and accuracy were evaluated based on FISH as a gold-standard reference. Results: In BC, the expression level of HER2 protein detected by IHC was overall IHC 0 in 28.7%, 1+ in 18.9%, 2+ in 27.3% and 3+ in 25.1%, respectively, while in GC, the expression level was 60.7%, 18.6%, 14.8% and 5.9%, respectively. Log2ratio was used to assess ERBB2 amplification status detected by NGS. According to the FISH results of 34 other samples with high sensitivity (98%) and specificity (100%), the threshold was determined as 0.5. 8 and 10 samples of IHC 1+/2+ met the cutoff in BC and GC, respectively. In 63 BC, there were 17 positive and 46 negative by FISH. According to the threshold, the sensitivity and specificity of NGS detection was 94.1% and 97.8%, respectively. The proportion of samples with IHC 2+ that couldn't determine NGS ERBB2 status was 49.2%. However, except for false positive and false negative, the NGS results were concordant with FISH. In 45 GC, there were 5 positive and 40 negative by FISH. The specificity and sensitivity was 97.5% and 40%, respectively. In 4 samples with IHC 2+, 2 of them were discordant with the results of NGS and FISH. All IHC 1+ didn't meet the cutoff of NGS and was FISH negative in 108 samples. The accuracy of NGS in ERBB2 detection was 96.8% and 91.1% for BC and GC, respectively. Conclusions: Our data indicated that the NGS-based detection of ERBB2 amplification had high sensitivity, specificity and accuracy. In samples with IHC 1+/2+, the results of NGS detection were high concordant with FISH detection.

scholarly journals Point-Counterpoint: Meningitis/Encephalitis Syndromic Testing in the Clinical Laboratory

2018 ◽  
Vol 56 (4) ◽  
Author(s):  
Jennifer Dien Bard ◽  
Kevin Alby
Keyword(s):  
Los Angeles ◽  
Clinical Laboratory ◽  
Salt Lake ◽  
Health Care Systems ◽  
False Negative ◽  
Salt Lake City ◽  
Respiratory Pathogens ◽  
Negative Results ◽  
Care Systems ◽  
The University

INTRODUCTION Syndromic panels were first FDA cleared for detection of respiratory pathogens in 2008. Since then, other panels have been approved by the FDA, and most recently, the FilmArray meningitis/encephalitis panel (BioFire, Salt Lake City, UT) has become available. This assay detects 14 targets within 1 h and includes pathogens that typically cause different manifestations of infection, although they infect the same organ system. Several studies have reported both false-positive and false-negative results with this test, and all agree that the cost is significant. As with other panels, health care systems have adopted different strategies for offering this assay. Some have implemented strategies to limit the use of the test to certain patient populations, others have elected not to offer the test, and others have elected not to offer the test and instead request that providers order specific PCRs for the pathogens that best fit the patient's symptoms. In this Point-Counterpoint, Jennifer Dien Bard of the Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles, and of the Keck School of Medicine at the University of Southern California explains why laboratories should offer these assays without restriction. Kevin Alby of the University of Pennsylvania explains the concerns about the use of these assays as first-line tests and why some limitations on their use might be appropriate.

Performance criteria for rapid screening methods to detect mycotoxins

2014 ◽  
Vol 7 (4) ◽  
pp. 439-447 ◽  
Author(s):  
C. von Holst ◽  
J. Stroka
Keyword(s):  
False Negative ◽  
Screening Method ◽  
Performance Criterion ◽  
Performance Criteria ◽  
Rapid Screening ◽  
Cost Ratio ◽  
Screening Methods ◽  
Method Performance ◽  
Official Control ◽  
The Impact

The paper describes the validation of screening methods that are used for official control to classify samples into negative and suspect positive samples. The concept is based on the principle that negative samples are considered as compliant, whereas suspect positive samples need to be re-analysed with confirmatory methods. An important performance criterion often used is a maximum value of 5% for the probability of false negative results obtained on samples that contain the analyte at the legal limit. Since the result of analysis is a binary decision, specific validation schemes need to be applied. The paper places emphasis on practical aspects of the calculation of the method performance characteristics, which are required to check whether the methods fulfil the performance criterion. The paper shows that screening methods based on a visual inspection, e.g. a dipstick, require special data treatment. In contrast there are many methods where the classification into negative and suspect positive samples is based on the comparison of a measured response against a cut-off value. This type of methods can be validated with quantitative statistics. The paper also elaborates on the calculation of the rate of false positive results of compliant samples. In addition the impact on the economical aspect of the use of the screening method is estimated, taking into account external factors such as the cost ratio between the screening and the confirmatory method and the occurrence of non-compliant samples in the entire population of the samples.

scholarly journals Clinical and immunological features of infants born from mothers with threatened miscarriage

2013 ◽  
Vol 10 (4) ◽  
pp. 54-59
Author(s):  
S M Kolesnikova ◽  
H A Levkova ◽  
S N Denisova ◽  
S V Bogdanova
Keyword(s):  
Cellular Immunity ◽  
Clinical Laboratory ◽  
Immunological Tolerance ◽  
Physical Growth ◽  
Threatened Miscarriage ◽  
Central Nervous System Depression ◽  
Initial Symptoms ◽  
Somatic Status ◽  
The Central Nervous System ◽  
Maternal Disease

Most of researchers denote predominance of morbid conditions, originated from prenatal period of life, in infant disease structure. To their mind, these points to the interrelation between these diseases and mother’s somatic health and het gestation course. The goal of the research was to study how the feto-maternal disease influences clinical and immunological status of infants at neonatal age. The observance has been held under 73 infants, born from mothers with different types of gestation. The first group contained infants, born from mothers with physiologic gestation course, the second group - infants, born from mothers with threatened miscarriage. The clinical laboratory examination of newborns and infants included evaluation of anthropometric characteristics, somatic status, ultrasound examination of thymus, indexes of cellular immunity. The examiners used diagnostic immunoenzymometric test-systems of JSC «Vektor-Best» and standardized methods. The newborns of the second group had the most apparent aberrations of physical growth and development. The central nervous system depression in the form of encephalitic depression syndrome has been detected as the common consequence of severe prenatal fetal hypoxia and neonatal asphyxia of second group newborns. Moreover, infants, born from mothers with threatened miscarriage, predominantly had «abnormal small thymus’s syndrome». The results of immunological examinations showed that infants’ cellular-immunity changes depended on nature of mother’s gestation disorders (suppressor type dependence). The developing of evident immune suppression with signs of immunological tolerance disorder has been detected amongst infants, born from mothers with threatened miscarriage. The initial symptoms were allergenic dermhelminthiasis.

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