scholarly journals Second-Generation Platelet Concentrates (PRFs): Estimation of Cellular Content

2021 ◽  
Vol 12 (4) ◽  
pp. 4747-4754

We performed a study to evaluate the amount of Platelets and Leukocytes in a second-generation solid platelet concentrates in terms of Sensitivity, Specificity, Positive Predictive Value (VP+), Negative Predictive Value (VP-), False Negative Proportion, and False Positive Proportion of our Statistical Method. Blood was collected in anticoagulant-free PET tubes with silica for clot production and PRF membranes. The membranes and clots produced were examined. In a previous work, the authors, starting from the results obtained in Kitamura's work, wanted to elaborate a simpler and inexpensive system to calculate the exact amount of platelets and leukocytes contained in PRF, compared to the one present in whole blood, starting from a simple "haemochromocytometric examination". In this study, the authors have evaluated the Sensitivity, Specificity, Positive Predictive Value (VP+), Negative Predictive Value (VP-), False Negative Proportion, and False Positive Proportion of the "Statistical Method". Using the Statistical Method, we have that by reducing by 34.12% (±28.2) the value of leukocytes obtained from the CBC examination. We obtained the value of leukocytes contained in the PRF membrane by t-PA digestion and by reducing by 15.12% (±24.87) the value of platelets obtained by the same method, we obtained the value contained in solid platelet concentrates by t-PA digestion. The method thus proposed demonstrated a Se=0.75; Sp=0.86; VP+=0.75; VP-=0.86 for platelet counts, Se=0.47; Sp=0.66; VP+=0.80; VP-=0.30 for leukocyte counts. Conclusion: Our study sought to standardize the PRF preparation procedure by validating a statistical system to calculate the exact amount of platelets and leukocytes in second-generation solid platelet concentrates, making it easy to evaluate individual PRF arrays on time in the clinical setting. The Statistical method compared to the digestive method with t-PA for leukocyte and platelet counts demonstrated equal validity for platelets, but not so for leukocytes.

1970 ◽  
Vol 28 (5) ◽  
Author(s):  
Nasar Alwahaibi ◽  
Asmaa Alghallabi ◽  
Shadia Alsinawi ◽  
Najat Aldairi

BACKGROUND: Cytological smear and cell block (CB) are routinely used to diagnose non gynaecologic specimens. However, there is scanty information in the literature to compare cytological smear and CB with the corresponding tissue biopsies. This study is aimed at evaluating the accuracy of cytological smear and CB in the diagnosis of malignant tumours in non-gynaecologic specimens.MATERIALS AND METHODS: A total of 70 malignant cases were subjected to cytological smear and CB. Corresponding histopathology was also included. The most frequent immunomarkers found between CB and tissue biopsies were also correlated. Accuracy, sensitivity, specificity, positive predictive value, negative predictive value, false positive and false negative values were analyzed for each method.RESULTS: The accuracy, sensitivity and positive predictive value for cytological smear were 92.8%, 100.0% and 92.9%, whereas for CB were 91.4%, 98.4% and 92.7%, respectively. In CB method, the accuracy, sensitivity and positive predictive value for CK7 were 88.9%, 91.7% and 95.6%, whereas for CK5/6 were 75%, 100% and 57.1%, respectively.CONCLUSION: Cytological smear and CB are very sensitive and accurate in the detection of malignant tumours in nongynaecologic specimens. Additional corresponding tissue biopsiesshould be re-evaluated. 


PEDIATRICS ◽  
1982 ◽  
Vol 70 (3) ◽  
pp. 464-467 ◽  
Author(s):  
M. Jeffrey Maisels ◽  
Sarah Conrad

A total of 292 transcutaneous bilirubin (TcB) measurements were performed in 157 white full-term infants: 157 were obtained from the forehead and 135 from the midsternum. TcB measurements correlated well with serum bilirubin determinations (r = .93, P < .0001). The sensitivity of the test was 100% and the specificity 97%. It was possible to establish guidelines for the TcB measurement which identified all infants whose serum bilirubin concentrations exceeded 12.9 mg/100 ml (221 µmoles/liter) with no false-negative and only five false-positive determinations (3%). The positive predictive value for the TcB measurements was 58%. This implies that, in our population, an infant with a TcB index ≥24 has a 58% chance of having a serum bilirubin concentration >12.9 mg/100 ml. The negative predictive value was 100%. Thus, a negative test will correctly predict the absence of hyperbilirubinemia in all cases. As these measurements were obtained prospectively in a well-baby population with a prevalence of hyperbilirubinemia (>12.9 mg/100 ml) of 4.5%, the positive predictive value should be applicable to other similar populations and will, in fact, increase in populations with a higher prevalence of hyperbilirubinemia. TcB measurements can be recommended for the identification of significant neonatal jaundice in full-term infants. It is important to recognize, however, that because of potential variations in TcB meters as well as serum bilirubin measurements in different laboratories, each institution should establish its own criteria for the use of this instrument.


2020 ◽  
Author(s):  
Bei Zhang ◽  
Li Zhang ◽  
Bingyang Bian ◽  
Fang Lin ◽  
Zining Zhu ◽  
...  

Abstract BACKGROUND Whole body diffusion weighted imaging (WB-DWI) is commonly used for the detection of multiple myeloma (MM). Comparative data on the efficiency of WB-DWI compared with 18 F positron emission tomography computed tomography ( 18 F-FDG PET/CT) to detect MM are lacking. METHODS This was a retrospective, single-center study of twenty-two patients with MM enrolled from January 2019 to December 2019. All patients underwent WB-DWI and 18 F-FDG PET/CT. Pathological and clinical manifestations as well as radiologic follow-up were used for diagnosis. The overall accuracy, sensitivity, specificity, positive predictive value and negative predictive value of both methods were compared. The appearance diffusion coefficient (ADC) values of MM lesions and false-positive lesions were estimated. RESULTS A total of 214 MM bone lesions were evaluated. WB-DWI showed a higher overall accuracy than PET/CT (75.7% and 55.6%, respectively; < 0.05). However, for sensitivity, specificity, positive predictive value and negative predictive value, there were no significant differences for WB-DWI vs PET/CT (99.3% and 83.9%, 64.9% and 94.8%, 63.6% and 54.2%, 98.1% and 65.3%, respectively). The ADC value for MM lesions was significantly lower than that for false-positive lesions (p < 0.001). Receiver operating curve (ROC) curve analysis showed that the AUC was 0.846, and when the cut-off value was 0.745×10 -3 mm 2 /s, the sensitivity and specificity were 86.0% and 82.4%, respectively, which distinguished MM lesions from non-MM lesions. CONCLUSION WB-DWI may be a useful tool for the diagnosis of MM bone disease due to to higher overall accuracy and measurements of ADC values compared with PET/CT.


2019 ◽  
Vol 41 (06) ◽  
pp. 688-694
Author(s):  
Ron Bardin ◽  
Noga Perl ◽  
Reuven Mashiach ◽  
Eitan Ram ◽  
Sharon Orbach-Zinger ◽  
...  

Abstract Purpose To investigate the accuracy of ultrasound in the diagnosis of adnexal torsion. Materials and Methods Retrospective cohort analysis of 322 women, presenting to a tertiary medical center with acute abdominal pain, who underwent gynecological examination, sonographic evaluation and laparoscopic surgery, between 2010 and 2016. Findings for adnexal torsion were compared among three groups: positive sonographic findings consistent with surgically confirmed adnexal torsion (true positive, n = 228); negative sonographic findings inconsistent with surgically confirmed adnexal torsion (false negative, n = 42); and positive sonographic findings inconsistent with a surgical diagnosis other than adnexal torsion (false positive, n = 52). Outcome measures were sensitivity and positive predictive value of ultrasound, and its specific features, for the diagnosis of adnexal torsion. Results The sensitivity of ultrasound for adnexal torsion diagnosis was 84.4 %, and the positive predictive value was 81.4 %. Edematous ovary and/or tube, as well as positive whirlpool sign had the highest sensitivity and positive predictive value. The false-negative group had the highest frequency of ovarian cysts (p = 0.0086) and the lowest frequency of ovarian edema (p < 0.0001). The false-positive group had the lowest proportion of pregnant women (p = 0.0022). Significantly more women in the true-positive group had a prior event of adnexal torsion (p = 0.026). Conclusion Ultrasound examination is highly accurate in the diagnosis of adnexal torsion. Clinicians should be aware of the presence of demographic and clinical characteristics that may positively or negatively affect sonographic diagnostic accuracy.


2017 ◽  
Vol 5 (1) ◽  
pp. 12-13
Author(s):  
Ishwor Raj Devkota ◽  
S. Bhandary ◽  
S. Karki

Objectives: To predict malignant nodules in solitary thyroid nodules on clinical assessment.Materials and methods: A total of 48 cases with thyroid nodule were clinically assessed in detail and underwent the standard thyroid surgery at BPKIHS, Dharan during the period of one year (April 2012 to march 2013).Results: The mean age was 41.42 years with female to male ratio of 15:1. Most of the patients were euthyroid (73%). Majority of the thyroid nodules were malignant (85.4%) and only 14.6% were benign on clinical assessment. The sensitivity of clinical evaluation was 84.6%, specificity 13.6%, positive predictive value 53.6%, negative predictive value 42.8%. Percentage of the false negative, false positive and overall accuracy was 57.1%, 46.3% and 52% respectively.Conclusion: Even though the sensitivity is high, clinical assessment has low specificity. So we cannot rely on clinical assessment in predicting malignancy in the thyroid nodules.  


2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Yanli Zhu ◽  
Yuntao Song ◽  
Guohui Xu ◽  
Zhihui Fan ◽  
Wenhao Ren

Abstract Objective FNA is a simple, safe, cost-effective and accurate diagnostic tool for the initial screening of patients with thyroid nodules. The aims of this study were to determine the diagnostic utility of FNAC performed in our institution, assess the cytomorphologic features that contribute to diagnostic errors and propose improvement measures. Methods A total of 2781 FNACs were included in the study, and 1122 cases were compared with their histological diagnoses. We retrospectively reexamined our discordant (both false-negative and false-positive) cases and performed a systematic review of previous studies on causes of misdiagnoses. Results When DC V and DC VI were both considered cytologic-positive, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy were 98.3, 30.9, 94.9, 58.3 and 93.5%, respectively. If DC VI was considered cytologic-positive, the sensitivity, specificity, PPV, NPV and diagnostic accuracy of FNAC were 98.0, 84.0, 99.4, 58.3, and 97.5% respectively. The main cause of false-negative diagnoses was sampling error (13/15, 86.7%), while interpretation error led to the majority of the false-positive diagnoses (38/47, 80.9%). Overlapping cytological features in adenomatous hyperplasia, thyroiditis and cystic lesions were the major factors contributing to interpretation errors, while the size and number of nodules may have led to false-negative diagnoses because of heterogeneity and unsampled areas. Conclusions The sensitivity and PPV of thyroid FNAC in our institution were higher than those in the published data, while the specificity and NPV were lower. Regarding the FNA category DC V, a frozen section analysis during diagnostic lobectomy is necessary. Multiple passes should be performed in various parts of a large nodule or from different nodules to reduce the risk of false-negative findings. Cytopathologists should strengthen their criteria for the identification of adenomatous hyperplasia, thyroiditis and cystic lesions to avoid false-positive diagnoses. NIFTP has little effect on diagnostic accuracy and the distribution of diagnostic errors.


2020 ◽  
Vol 38 (4_suppl) ◽  
pp. 288-288
Author(s):  
Takeyuki Wada ◽  
Takaki Yoshikawa ◽  
Ayako Kamiya ◽  
Keichi Date ◽  
Tsutomu Hayashi ◽  
...  

288 Background: D2 surgery is required for clinical T1 gastric cancer with nodal swelling, however, D2 has a higher risk for morbidity than D1/D1+. Moreover, previous study demonstrated that the false positive rate for nodal diagnosis in clinical T1 was very high. To select optimal surgery with high probability, we explored risk factors for false positivity in clinical T1 disease. Methods: Patients who underwent radical gastrectomy for clinical T1 gastric cancer between April 2015 and June 2019 were enrolled. Accuracy, sensitivity, specificity, positive predictive value, and negative predictive values for nodal diagnosis were retrospectively investigated. The risk factors for false positivity were also analyzed by the following factors; age, sex, histological type, tumor size, tumor depth, location, tumor type, presence of ulcer, and timing of CT that is (1) the patients who underwent primary endoscopic mucosal dissection (ESD) but resulted in non-curative resection, then received CT to proceed to surgery (delayed CT group) or (2) the other patients who had received CT before primary surgery or before non-curative ESD (primary CT group). Results: A total of 679 patients were examined in the present study. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 83.5% (567/679), 14.3% (13/91), 94.2% (554/588), 27.7% (13/47), and 87.7% (554/632), respectively. The false positive rate was 72.3% (34/47). In univariate analysis, differentiated tumor ( p= 0.012) and delayed CT (p < 0.001) were associated with the false positivity. Multivariate analysis revealed that delayed CT (OR, 4.534; p < 0.001) was a sole significant risk factor for false positivity. False positive rate was 100% (13/13) in the delayed CT group and 61.8% (21/34) in the primary CT group ( p= 0.009). Conclusions: False positive rate was high in clinical T1 disease, especially when the patients received delayed CT after non-curative ESD. D2 surgery would be unnecessary even though nodal swelling was detected in CT after non-curative ESD.


2006 ◽  
Vol 105 (5) ◽  
pp. 682-688 ◽  
Author(s):  
Irene C. van der Schaaf ◽  
Birgitta K. Velthuis ◽  
Marieke J. H. Wermer ◽  
Nanne J. Frenkel ◽  
Charles B. L. M. Majoie ◽  
...  

Object Multislice computed tomography (CT) angiography may be useful for screening patients with intracranial aneurysms that are treated with clip occlusion. However, cobalt clips produce much more artifact on CT scans than titanium clips, which may hamper the evaluation of the image obtained at the clip site. Methods The authors screened 415 patients with previously ruptured aneurysms that had been treated using cobalt clips. Screening was performed using multislice CT angiography. The feasibility of this modality for screening these patients (based on the complication risk, CT angiography quality, and artifact avoidance) and interobserver agreement were evaluated. Patients in whom the presence of an aneurysm was suspected based on results of CT angiography studies underwent digital subtraction (DS) angiography. False-negative and false-positive findings were recorded, and the positive predictive value (PPV) was calculated. Eight patients (1.9%) had allergies to the contrast material. The quality of the CT angiography image was suboptimal in 14%. In 52%, clip artifacts hampered evaluation of the clip site. In 65 patients who underwent DS angiography, there were nine false-positive and eight false-negative reports related to aneurysms that were either small, located at the clip site, or were infundibula. The PPV on a per-patient basis was 86% (95% confidence interval [CI] 75–94%); for aneurysms at the clip site it was 83% (95% CI 61–95%); and for aneurysms at different locations it was 91% (95% CI 81–97%). The interobserver agreement was good (κ = 0.69; 95% CI 0.60–0.78). Conclusions Except for the evaluation of images from the clip site, CT angiography has good feasibility with good PPV and interobserver agreement. Drawbacks are that very small aneurysms can be missed and that visualization is poor at the clip site in patients in whom cobalt clips have been placed for occlusion. This second problem can be expected to resolve with the increasing use of titanium clips.


2021 ◽  
Vol 27 ◽  
Author(s):  
Dorottya Bús ◽  
Gyöngyi Nagy ◽  
Róbert Póka ◽  
György Vajda

Abstract: Purpose: In the developed world, endometrial cancer is one of the most common malignant gynecological cancer types. Due to the highly available diagnostic modalities and patient education, the early detection of the tumor leads to high overall survival.Methods: In this study we analyzed the reliability of preoperative MRI findings in the staging of early stage endometrial cancer, as well as the clinical characteristics of patients underwent radical hysterectomy and the histopathologic evaluation of their tumor, with the retrospective data of radical hysterectomies performed in our hospital between 2010 and 2019.Results: The accuracy, sensitivity, specificity, negative- and positive predictive value of MRI regarding stage were 94.7, 63.3, 94.8, 83.8, and 83.8%, respectively. The accuracy, sensitivity, specificity, negative- and positive predictive value of MRI for the detection of the myometrial invasion were 69.8, 80.0, 60.8, 64.3, and 77.5%, respectively. The accuracy, sensitivity, specificity, negative- and positive predictive value of MRI for the detection of lymph node metastases were 78.1, 28.6, 82, 11.1, and 93.6%, respectively.Conclusions: Based on our results, MRI is the method of choice in terms of evaluating overall staging, as well as myometrial invasion, as its specificity and negative predictive value are relatively high. However, systematic lymphadenectomy showed improved cancer-related survival and recurrence-free survival. Our studies showed that the diagnosis of lymph node metastases is difficult with MRI modality since hyperplastic and metastatic nodes cannot easily differentiate, leading to a high percentage of false-positive results. Therefore, other imaging modalities may be used for more accurate evaluation. New findings of our study were that the role of the radiologist’s expertise in the evaluation of MR imaging plays an essential role in lowering false-negative and false-positive results. Therefore, findings evaluated by a radiologist with high-level expertise in gynecological imaging can complement the clinical findings and help substantially define the needed treatment.


2020 ◽  
Vol 9 (3) ◽  
pp. 190-194
Author(s):  
Naureen Saeed ◽  
Fatima-tuz-zuhra ◽  
Nadeem Ikram ◽  
Farhana Shaukat ◽  
Fareeha Sardar

Background: Pakistan faces an immense burden of pulmonary tuberculosis (TB) due to large number of cases and limited resources. Despite the recent advancement in the diagnostic techniques for pulmonary TB, smear microscopy is still a useful technique for the diagnosis of this disease. This study was conducted in order to compare the diagnostic value of Auramine stain with the conventional Ziehl-Neelsen (ZN) stain on the sputum smear for the diagnosis of pulmonary TB, keeping GeneXpert MTB/RIF as the gold standard. Method: This cross-sectional study was conducted on 356 suspected patients of pulmonary TB referred to the Pathology laboratory from TB ward and OPD of District Head Quarter (DHQ) teaching hospital Rawalpindi, Pakistan. Sputum specimen were collected and two smears were prepared from each sputum sample on which Auramine phenol and Ziehl-Neelsen staining were carried out as per WHO recommendations. All these samples were further tested using Gene Xpert MTB/RIF technique. The sensitivity, specificity, Positive predictive value (PPV) and Negative predictive values (NPV) of ZN and Auramine stain were calculated and compared with GeneXpert MTB/RIF technique. Results: Out of the total 356 samples, 64(18%) were positive and 291(82%) were negative by GeneXpert which was taken as the gold standard. On comparison with GeneXpert, percentage of true positive was greater in case of Auramine than ZN stained samples (16.29% versus 12.92%), while the percentage of false positive was same for both staining techniques (0.28%). There were lesser false negative cases observed in samples stained by Auramine as compared to the ones stained by ZN (1.68% versus 5.05%). The sensitivity, specificity, positive predictive value and negative predictive values were 97.87%, 94.17%, 71.88 and 99.66%, respectively for the ZN staining and 98.31%, 97.98%, 90.63% and 99.66% respectively, for the Auramine phenol staining. Conclusion: Smear microscopy using Auramine phenol stain is a useful technique for the diagnosis of pulmonary TB. The Auramine phenol staining with fluorescent microscopy is found to be superior to ZN staining because of higher sensitivity and specificity. Keywords: Auramine phenol, Fluorescence microscopy, GeneXpert, Mycobacterium tuberculosis, Ziehl-Neelsen


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