Medical device manufacturer, BioMérieux, has issued a medical device safety alert concerning its VITEK 2 Identification / Antimicrobial Susceptibility Test Cards.
The manufacturer has identified a potential issue related to the white pouch which contains VITEK 2 test cards for the product lots. The manufacturer has determined that the integrity of some of the VITEK 2 test card pouches may be compromised. Based on the investigation, a compromised test card pouch can impact card reagents due to the entry of moisture.
The white pouch is composed of five layers of material, four of which are clear. All five layers must be compromised for a pouch to potentially allow moisture to enter the pouch. Upon visual inspection of the pouch, user may notice a small puncture or tear in the packaging at the "stitch seal". Per product labeling, do not use the card if the pouch (the white protective package cover) is damaged. Based on internal testing, approximately 20% of card pouches exhibited a visual defect; the majority of card pouches with this visual defect maintained pouch integrity, i.e. at least one of the five material layers remained intact. However, 1 in 200 (0.5%) card pouches that passed careful visual inspection failed further integrity tests, indicating the potential for entry of moisture.
Studies by the manufacturer have demonstrated that a test card pouch defect can allow entry of moisture which can impact the test card reagents. Moisture sensitivity can lead to antibiotic degradation (loss of potency). The anticipated consequence would be elevated MIC results of some antimicrobials (leading to false-resistant results). The antimicrobial class most affected by moisture is the beta-lactam class. This includes penicillins, cephalosporins, and carbapenems. The most moisture-sensitive of the beta-lactams is imipenem. Therefore, it is the best indicator of a pouch defect. Two other moisture-sensitive antimicrobials are erythromycin and nitrofurantoin.
One exception to the expected elevation in MICs (or false resistance) that can occur due to the pouch defect is the ESBL (Extended-Spectrum β-Lactamase) test, which utilizes clavulanic acid in combination with three cephalosporins. Clavulanic acid is also moisture sensitive, and if degraded, the ESBL test could be falsely negative. The Advanced Expert System will determine presence of an ESBL phenotype based on results of all beta lactams, including the ESBL test. Therefore, the impact of a false negative ESBL test should be minimal.
For VITEK 2 Identification cards, urea (URE) may be sensitive to moisture and a false positive reaction may occur. However, there is low risk of impact to identification result as the identification (ID) algorithm generally allows two atypical reactions and will still provide a correct identification with a high degree of confidence. The knowledge bases are designed to account for both typical and atypical strains so an aberrant reaction should have low impact on identification results.
The manufacturer advises users that it is not necessary to discard all cards from an impacted lot. Users are recommending follow the instructions mentioned in FSN in the affected lots prior to use.
According to the local supplier, the affected products are distributed in Hong Kong.
If you are in possession of the affected products, please contact your supplier for necessary actions.
Posted on 24 April 2017