Background: The PGDprime ® test was updated to enable Acinetobacter spp. detection to respond to morbidity and mortality events in 2018 and 2020 involving platelets contaminated with Acinetobacter-calcoaceticus-baumannii complex (ACBC). In one morbidity event, the first-generation PGD test failed to detect ACBC. In two other reported events, pathogen-reduced (PR) platelets contaminated with ACBC and other bacteria led to patient morbidity and one death. Study Design and Methods: A polyclonal antibody to Acinetobacter was integrated in the test device and evaluated for detection of Acinetobacter spp., including the ACBC isolate recovered in one of the 2018 contamination events. Limits of Detection for various Acinetobacter strains were determined in dilution studies. Detection of Acinetobacter growing in platelets after an initial low inoculum was evaluated. Use of the updated test as a secondary test after pathogen reduction was also evaluated by testing at 12-h intervals PR platelet units inoculated with low levels of the 3 species reported in the fatal PR platelet: ACBC, Staphylococcus saprophyticus, and Leclercia adecarboxylata.Results: The test detected several Acinetobacter strains at the clinically relevant CFU/ml levels associated with septic transfusions and successfully detected Acinetobacter growing in various non-PR platelet types after an initial low inoculum. In PR platelets, the test yielded a positive result with the 3 implicated bacteria in 48 h or less after inoculation, or 48-72 h earlier than the reported time of transfusion of contaminated PR platelets. Conclusion: PGDprime was improved to detect Acinetobacter and has shown utility to interdict contaminated PR platelets.

Background: The Verax PGD rapid test for bacteria in platelets (PLTs) has been updated to simplify workflow and improve specificity and sensitivity by employing a novel sequential format. The performance of this updated version, called PGDprime, was evaluated to determine its suitability for use as an FDAcleared "safety measure" to supplant the current PGD test. Study design and methods: Three consecutive cGMP-manufactured lots of PGDprime were evaluated for specificity (at three separate sites), sensitivity, reproducibility, interfering substances, assay robustness, and detection in analytical growth and ultralow-inoculum growth studies. PGDprime's performance was compared to that of PGD. Results: Specificity studies yielded no false-positive results among 3802 individual indate PLTs of seven different types (observed specificity, 100%). PGDprime detected all 10 PGD claim bacteria at the same limit of detection or better. Wildtype Gram-negative bacteria growing in PLTs were detected at earlier elapsed times than PGD by 12 to 30 hours. In growth studies, PGDprime detected bacteria growing in PLTs within the same 12-hour interval as PGD or 12 to 48 hours earlier. Assay reproducibility was not affected by operator, day of test, or manufacturing lot. PGDprime tolerated a wide variation in volume transfers, timing, temperature, and relative humidity and was not affected by 15 of 16 potential interferents found in samples at extremely high or low levels. Conclusion: The PGD test has been successfully updated to PGDprime with an innovative sequential assay format to deliver a robust simplified workflow and improved specificity and sensitivity.

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