Use of Middleware Data to Dissect and Optimize Hematology Autoverification.

BACKGROUND: Hematology analysis comprises some of the highest volume tests run in clinical laboratories. Autoverification of hematology results using computer-based rules reduces turnaround time for many specimens, while strategically targeting specimen review by technologist or pathologist. METHODS: Autoverification rules had been developed over a decade at an 800-bed tertiary/quarternary care academic medical central laboratory serving both adult and pediatric populations. In the process of migrating to newer hematology instruments, we analyzed the rates of the autoverification rules/flags most commonly associated with triggering manual review. We were particularly interested in rules that on their own often led to manual review in the absence of other flags. Prior to the study, autoverification rates were 87.8% (out of 16,073 orders) for complete blood count (CBC) if ordered as a panel and 85.8% (out of 1,940 orders) for CBC components ordered individually (not as the panel). RESULTS: Detailed analysis of rules/flags that frequently triggered indicated that the immature granulocyte (IG) flag (an instrument parameter) and rules that reflexed platelet by impedance method (PLT-I) to platelet by fluorescent method (PLT-F) represented the two biggest opportunities to increase autoverification. The IG flag threshold had previously been validated at 2%, a setting that resulted in this flag alone preventing autoverification in 6.0% of all samples. The IG flag threshold was raised to 5% after detailed chart review; this was also the instrument vendor's default recommendation for the newer hematology analyzers. Analysis also supported switching to PLT-F for all platelet analysis. Autoverification rates increased to 93.5% (out of 91,692 orders) for CBC as a panel and 89.8% (out of 11,982 orders) for individual components after changes in rules and laboratory practice. CONCLUSIONS: Detailed analysis of autoverification of hematology testing at an academic medical center clinical laboratory that had been using a set of autoverification rules for over a decade revealed opportunities to optimize the parameters. The data analysis was challenging and time-consuming, highlighting opportunities for improvement in software tools that allow for more rapid and routine evaluation of autoverification parameters.

Exponential increase in neutralizing and spike specific antibodies following vaccination of COVID-19 convalescent plasma donors.

BACKGROUND: With the recent approval of COVID-19 vaccines, recovered COVID-19 subjects who are vaccinated may be ideal candidates to donate COVID-19 convalescent plasma (CCP). CASE SERIES: Eleven recovered COVID-19 patients were screened to donate CCP. All had molecularly confirmed COVID-19, and all but one were antibody positive by chemiluminescence immunoassay (DiaSorin) prior to vaccination. All were tested again for antibodies 11-21 days after they were vaccinated (Pfizer/Moderna). All showed dramatic increases (~50-fold) in spike-specific antibody levels and had at least a 20-fold increase in the IC50 neutralizing antibody titer based on plaque reduction neutralization testing (PRNT). The spike-specific antibody levels following vaccination were significantly higher than those seen in any non-vaccinated COVID-19 subjects tested to date at our facility. CONCLUSION: Spike-specific and neutralizing antibodies demonstrated dramatic increases following a single vaccination after COVID-19 infection, which significantly exceeded values seen with COVID-19 infection alone. Recovered COVID-19 subjects who are vaccinated may make ideal candidates for CCP donation.

Data on length of parathyroidectomy surgery and intraoperative parathyroid hormone (PTH) assay turnaround times following a switch in the location for intraoperative PTH testing from near point-of-care to central laboratory.

Intraoperative monitoring of parathyroid hormone (PTH) is commonly used during parathyroidectomies. There are a number of practical challenges in achieving rapid turnaround time (TAT) for intraoperative PTH testing, whether the testing is performed point-of-care, near point-of-care, or in a central clinical laboratory. In the related research article, we analyzed a decade of data from 3025 intraoperative PTH tests on 897 unique patients. Of these, 1787 tests on 514 unique patients (375 female, 139 male) occurred while intraoperative PTH measurement was done as near point-of-care testing; the remaining 1238 tests on 383 unique patients (282 female, 101 male) occurred after a switch to intraoperative PTH measurement by the hospital central laboratory. The data in this article provides the patient age, gender, location of surgery (main operating rooms vs. ambulatory surgery center), incision to close time for surgery, and operation start to end times. For the central laboratory testing, additional data are provided for the intraoperative PTH TAT. The analyzed data is provided in the supplementary tables included in this article. Plots of operation start and end times are also included. The dataset reported is related to the research article entitled "Evaluation of Switch from Satellite Laboratory to Central Laboratory for Testing of Intraoperative Parathyroid Hormone" [D. Jacob, G. Lal, D.R. Voss, T. Bebber, S.R. David, J. Kulhavy, S.L. Sugg, A.E. Merrill, M.D. Krasowski, Evaluation of Switch from Satellite Laboratory to Central Laboratory for Testing of Intraoperative Parathyroid Hormone, Pract. Lab. Med. (2020) 22: e00176] [1].

Evaluation of switch from satellite laboratory to central laboratory for testing of intraoperative parathyroid hormone.

OBJECTIVES: The aim of this study was to evaluate testing turnaround time (TAT) and incision to close time in parathyroid surgeries before and after switching intraoperative parathyroid hormone (PTH) testing from a near point of care location to a central clinical laboratory. DESIGN AND METHODS: This retrospective study covered a ten-year period. Both testing locations used the same Roche Diagnostics PTH immunoassay but on different analyzers. The predominant site for surgeries was the main operating rooms (ORs) in an adjacent building, with a limited number of parathyroid surgeries performed at a more distant ambulatory surgery center (ASC). Under ideal conditions, TAT for near point-of-care testing was 20 â€‹min, although multiple factors could increase TAT. Incision to close time from the electronic health record was used to define time of surgery. RESULTS: A total of 897 unique patients were identified for which 3031 orders for intraoperative PTH were placed (383 unique patients and 1244 orders after switch in testing site). The average total TAT times for testing (mean â€‹± â€‹SD) in the central laboratory were 23.9 â€‹± â€‹16.0 â€‹min (median, 22 â€‹min) for all specimens, 22.8 â€‹± â€‹7.9 â€‹min (median, 21 â€‹min) for main OR specimens, and 26.4 â€‹± â€‹7.1 â€‹min (median, 25 â€‹min) for ASC specimens. Incision to close time for parathyroidectomies showed decreases in mean, median, and standard deviation following testing change. CONCLUSIONS: Surgery time for parathyroidectomies may remain consistent or decrease if intraoperative PTH testing is moved from a near point of care to a central laboratory.

Head-to-Head Comparison of Two SARS-CoV-2 Serology Assays.

BACKGROUND: While molecular techniques remain the gold standard for diagnosis of acute SARS-CoV-2 infection, serological tests have the unique potential to ascertain how much of the population has been exposed to the COVID-19 pathogen. There have been limited published studies to date documenting the performance of SARS-CoV-2 antibody assays. METHODS: We compared the DiaSorin Liaison SARS-CoV-2 S1/S2 IgG and Roche Diagnostics Elecsys Anti-SARS-CoV-2 assays using 228 samples spanning patients with positive PCR for SARS-CoV-2, patients with compatible symptoms but negative PCR, pre-COVID specimens, and potential cross-reactives. RESULTS: Both assays detected antibodies in 18/19 samples collected at least one week after a positive PCR result. Neither method consistently detected antibodies in specimens collected within one week of a positive PCR result (sensitivity < 50%), but antibodies were detected by only Roche in four samples in this time frame. Using 139 pre-COVID and 35 PCR-negative samples, the Roche and DiaSorin assays demonstrated specificities of 100.0% and 98.9%, respectively. Neither assay demonstrated cross-reactivity from other coronaviruses (229E, HKU1, NL63, OC43), respiratory pathogens (adenovirus, metapneumovirus, rhinovirus/enterovirus), or antibodies to other viruses (HIV, EBV, CMV, HBV, HCV, HAV). DISCUSSION: Overall, the qualitative interpretations afforded by the Roche and DiaSorin assays agreed for 97% of samples evaluated. Minor discrepancies in sensitivity and specificity were observed between methods, with the differences in specificity more clinically significant for our low-prevalence population. For the DiaSorin assay, all disagreements with the Roche assay occurred in samples with quantitative signals near the cut-off determining positivity.

Impact of Endogenous and Exogenous Interferences on Clinical Chemistry Parameters Measured on Blood Gas Analyzers.

BACKGROUND: The prevalence of hemolysis, icterus, and lipemia (HIL) was determined for residual whole blood specimens analyzed for clinical chemistry parameters on blood gas analyzers. The frequency and potential impact of exogenous interference from iodide, salicylate, and thiocyanate (metabolite of sodium nitroprusside) on analysis of whole blood chloride was also assessed. METHODS: Over an approximately two month period at an academic medical center, indices for HIL were determined on Roche cobas c502 analyzers for 1,986 residual whole blood specimens that had been previously analyzed for clinical chemistry parameters on Radiometer ABL90 FLEX blood gas analyzers. To examine exogenous interferences, retrospective analysis was performed over multiple years to ascertain whether patient samples analyzed for whole blood chloride were potentially affected by interference from iodide, salicylate, or thiocyanate. RESULTS: Some degree of hemolysis (defined as hemolysis index of greater than 60) was present in 9.7% of the whole blood specimens. Increasing rates of hemolysis were associated with higher whole blood potassium concentrations. Nearly 60% of specimens with potassium concentrations between 6.0 and 6.9 mEq/L had hemolysis indices of 100 or greater, and 75% of specimens with a potassium concentration of 7.0 mEq/L or greater were severely hemolyzed (hemolysis index of 300 or greater). In contrast to the hemolysis results, icterus and lipemia were determined to have minimal impact on patient results. For the exogenous interferences, we did not identify any patient samples where elevated salicylate levels or pharmaceutical iodide administration overlapped with whole blood chloride analysis (out of 75,887 and 169,229 total chloride measurements, respectively). We did, however, find that for patients receiving nitroprusside therapy in the inpatient setting, whole blood chloride concentrations were significantly higher during nitroprusside therapy [106.7 +/- 6.2 mEq/L (mean, SD)] compared to before or after nitroprusside therapy (103.1 +/- 7.7 mEq/L). CONCLUSIONS: In this analysis of whole blood specimens, hemolysis is a common interference and likely to introduce meaningful biases, as illustrated with potassium analysis. Icterus, lipemia, salicylate, and iodide appear unlikely to cause clinically significant bias. Nitroprusside therapy introduced a slight rise in whole blood chloride concentrations that probably has minimal clinical significance.

Prevalence and Clinical Utility of "Incidental" Critical Values Resulting From Critical Care Laboratory Testing.

OBJECTIVE: Panels of clinical laboratory testing may generate "incidental" critical values from unordered parameters. Existing regulations do not clearly delineate guidelines for handling incidental critical values. The objective of this study was to examine the patterns and clinical utility of incidental critical values at 2 critical care laboratories within an academic medical center. METHODS: In this retrospective study, the electronic health record and laboratory information system were reviewed for incidental critical results obtained from blood gas analyzer analysis of whole blood specimens between November 2010 and August 2014. RESULTS: Within the retrospective time period, 9,092 incidental critical results were documented, of which only 11.8% were added to the "parent" order following clinical notification. Incidental critical results frequently occurred in patients who had recent critical values for the same parameter. CONCLUSION: In this study, at an academic medical center, incidental critical values associated with blood gas analyzers were added on at a low rate and often provided redundant information. Relative to the manual effort involved in care providers' notification and documentation of results, incidental critical values appear to have low clinical utility.

Autoverification in a core clinical chemistry laboratory at an academic medical center.

BACKGROUND: Autoverification is a process of using computer-based rules to verify clinical laboratory test results without manual intervention. To date, there is little published data on the use of autoverification over the course of years in a clinical laboratory. We describe the evolution and application of autoverification in an academic medical center clinical chemistry core laboratory. SUBJECTS AND METHODS: At the institution of the study, autoverification developed from rudimentary rules in the laboratory information system (LIS) to extensive and sophisticated rules mostly in middleware software. Rules incorporated decisions based on instrument error flags, interference indices, analytical measurement ranges (AMRs), delta checks, dilution protocols, results suggestive of compromised or contaminated specimens, and 'absurd' (physiologically improbable) values. RESULTS: The autoverification rate for tests performed in the core clinical chemistry laboratory has increased over the course of 13 years from 40% to the current overall rate of 99.5%. A high percentage of critical values now autoverify. The highest rates of autoverification occurred with the most frequently ordered tests such as the basic metabolic panel (sodium, potassium, chloride, carbon dioxide, creatinine, blood urea nitrogen, calcium, glucose; 99.6%), albumin (99.8%), and alanine aminotransferase (99.7%). The lowest rates of autoverification occurred with some therapeutic drug levels (gentamicin, lithium, and methotrexate) and with serum free light chains (kappa/lambda), mostly due to need for offline dilution and manual filing of results. Rules also caught very rare occurrences such as plasma albumin exceeding total protein (usually indicative of an error such as short sample or bubble that evaded detection) and marked discrepancy between total bilirubin and the spectrophotometric icteric index (usually due to interference of the bilirubin assay by immunoglobulin (Ig) M monoclonal gammopathy). CONCLUSIONS: Our results suggest that a high rate of autoverification is possible with modern clinical chemistry analyzers. The ability to autoverify a high percentage of results increases productivity and allows clinical laboratory staff to focus attention on the small number of specimens and results that require manual review and investigation.