The significance of repeat testing in Turkish blood donors screened with HBV, HCV and HIV immunoassays and the importance of S/CO ratios in the interpretation of HCV/HIV screening test results and as a determinant for further confirmatory testing

No relationship between the phenylalanine content of the feedings prior to the PKU screening test and a positive test result (≥4 mg/100 ml) could be demonstrated in a study of hospital records of 68 phenylketonuric, 14 atypical, and 26 hyperphenylalaninemic infants. The mean age at testing was 62.8 hours. The median intake before testing was 383 mg of phenylalanine with a range of 0 in five cases to over 3,000 mg for two late tested infants. One quarter of the infants with positive tests had ingested less than 200 mg of phenylalanine, while only one of the 11 with negative tests had less than 200 mg. The "missed" cases were represented at each intake interval, and intakes ranged from 174 to 1,326 mg phenylalanine. Screening test results ranged from 1 to 40 mg/100 ml (mean of 10.0) with wide variation at all intervals of phenylalanine intake. There was a gradual increase in mean levels from 7.1 mg/100 ml in the group with least intake to 13.0 for those having the most. This increase was attributable mainly to the PKUs whose mean levels were higher than those of the atypicals and hypers at all intake intervals, and went much higher with increased intake. Serial tests on 20 infants who had repeat testing in the first few days of life when feeding was documented demonstrated the rapid rise in serum levels in PKUs as feeding continued in contrast to the atypicals and hypers who showed only slight increases during this period. The authors conclude there is no evidence that missed cases are significantly related to feeding protein or early testing in routine PKU screening of the newborn infant.

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Evaluation of 10-Year Screening Test Results in Blood Donors Consulted To Our Blood Center

Jinekoloji Obstetrik Pediatri ve Pediatrik Cerrahi Dergisi ◽

10.5222/jopp.2013.136 ◽

2013 ◽

Vol 5 (3) ◽

pp. 136-141 ◽

Cited By ~ 1

Author(s):

Kamuran Sanli ◽

Nagehan Didem Sari ◽

Nevin Hatipoglu

Keyword(s):

Screening Test ◽

Blood Donors ◽

Test Results ◽

Blood Center

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Analisa Pengujian Repeatability Timbangan Elektronik dengan Metode Syarat Teknis Timbangan Non Otomatis dan Metode NMI Australia

Elinvo (Electronics Informatics and Vocational Education) ◽

10.21831/elinvo.v4i2.28356 ◽

2019 ◽

Vol 4 (2) ◽

pp. 176-183

Author(s):

Ponco Wali

Keyword(s):

Research Method ◽

Test Methods ◽

Test Results ◽

Repeat Testing ◽

Testing Method ◽

Technical Requirements

Testing repeat electronic scales with non-automatic scales technical requirements so far is fairly long if not using a calculator or computer. The aim of this research is to compare the repeatability testing method of electronic scales using methods according to the technical requirements of non-automatic scales and the Australian NMI method, both of which refer to OIML R76 in determining the validity or cancellation of electronic scales repeatability testing. This research method is done through repeat testing on 3 samples of electronic scales, then on each electronic scale 2 test methods are performed. The conclusion is that the electronic scales repeatability testing uses the non-automatic scales technical requirements method and the Australian NMI method has some differences although both refer to OIML R76. These differences include several points, namely the charge used, the method of adding additions, the formula for determining electronic scales, and different test results. The Australian NMI method is deemed to make it easier and more time efficient compared to the non-automatic weighing technical requirements method.

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The Wild West of Emergency Use Authorizations for SARS-CoV-2 Testing: What Could Be the True Sensitivity?

American Journal of Clinical Pathology ◽

10.1093/ajcp/aqaa161.312 ◽

2020 ◽

Vol 154 (Supplement_1) ◽

pp. S142-S143

Author(s):

S Dalal ◽

S Patel ◽

J M Petersen ◽

D Jhala

Keyword(s):

Medical Center ◽

Initial Result ◽

Reference Laboratory ◽

Test Results ◽

Rt Pcr ◽

Repeat Testing ◽

Parallel Testing ◽

Percent Agreement ◽

Instructions For Use ◽

Multiple Reference

Abstract Introduction/Objective SARS-CoV-2 is a pandemic that has required mobilization to meet urgent needs. In this mobilization, emergency use authorizations (EUA) have been issued by the FDA to expedite the deployment of these tests. This has led to a situation whereby sensitivity has not been rigorously studied for any of the assays with EUAs. Estimates can be extrapolated from the limited samples documented by the company in their instructions for use (IFU). Although the nationwide shortage of testing reagents prevent parallel testing of multiple platforms on all specimens, observations of repeat specimens at the Veteran Affairs Medical Center (VAMC) provides the first study in the literature of more complete data for SARS-CoV-2 nucleic acid (RT-PCR) assay on sensitivity on the Abbott (Abbott Park Ill) and Cepheid (Sunnyvale CA) assays. Methods A retrospective search was performed for all test results for SARS-CoV-2 by RT-PCR from 3/1/2020 to 4/14/2020 at Corporal Michael J. Crescenz Medical Center, in order to evaluate the sensitivity on Abbott m2000 and Cepheid platforms. Results across multiple reference laboratories and in-house testing platforms were collated in a table with all patients clinically requiring repeat testing recorded. Results 114/863 patients had repeat testing. The tests were performed initially by outside reference laboratories (25 patients), on the Abbott m2000 (63 patients), and Cepheid Infinity (26 patients). 15/114 (13%) had discordant results on repeat testing. This included 1 test initially done by a reference laboratory. 8 days after the initial result from the reference lab, a positive for the same patient was identified on the Abbott platform. 11 initial Abbott results were discordant on further repeat testing on two platforms - Abbott (6 patients) and Cepheid (5 patients) 1-6 days later. In addition, 3 initial Cepheid were discordant on further repeat testing by the same Cepheid platform (1-16 days later). Conclusion While the instructions for use for both platforms suggest 100% sensitivity and specificity (due to the 100% positive and negative percent agreement in limited specimens), the true sensitivity is less than 100%, particularly early in the course of the infection. In our study, the positive percent agreement (surrogate for sensitivity) was 83% for initial Abbott tests, 88% for initial Cepheid tests, and 95% by Reference laboratory platform.

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Is it enough for COVID-19 screening test? Limitation of swab test and general characteristics of mild symptom patients

Science Progress ◽

10.1177/00368504211026152 ◽

2021 ◽

Vol 104 (2) ◽

pp. 003685042110261

Author(s):

Sungwoo Choi ◽

Hyo Jeong Choi ◽

Ho Jung Kim

Keyword(s):

Screening Test ◽

Community Treatment ◽

Upper Respiratory Tract ◽

Test Results ◽

Rt Pcr ◽

Pcr Assay ◽

Positive Rate ◽

Upper Respiratory ◽

Polymerase Chain ◽

Discharge Criteria

The most common method for SARS-CoV-2 testing is throat or nasal swabbing by real-time reverse transcription polymerase chain reaction (RT-PCR) assay. In South Korea, drive-through swab test is used for screening system and community treatment centers (CTCs), which admit and treat confirmed COVID-19 patients with mild symptoms, are being used. This retrospective study was conducted on patients admitted to a CTC on March 6, 2020. A total of 313 patients were admitted. The nasal and throat swabs were collected from the upper respiratory tract, and a sputum test was performed to obtain lower respiratory samples. The positive rate of the first set of test, sputum test was higher than that of the swab test ( p = 0.011). In the second set of test, 1 week after the first ones, the rate of positive swab tests was relatively high ( p = 0.026). In the first set of test, 66 of 152 (43.4%) patients showed 24-h consecutive negative swab test results, when the sputum test results were considered together, that number fell to 29 patients (19.1%) ( p < 0.001). Also, in the second set of test, 63 of 164 (38.4%) patients met the discharge criteria only when the swab test was considered; that number fell to 30 (18.3%) when the sputum test results were also considered ( p < 0.001). Using the swab test alone is insufficient for screening test and discharge decision. Patients who may have positive result in the sputum test can be missed.

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