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Intended use: vitek® ms is a mass spectrometry system using matrix-assisted laser desorption/ionization time of flight mass spectrometry (maldi-tof ms) for the identification of microorganisms cultured from human specimens.The vitek® ms system is a qualitative in-vitro diagnostic device indicated for use in conjunction with other clinical and laboratory findings to aid in the diagnosis of bacterial, yeast and mold infections.Issue description: a customer in the united states notified biomérieux of a misidentification of two (2) staphylococcus aureus patient isolates as brucella sp.Associated with vitek ms instrument - ref.(b)(4), serial number (b)(6).The customer indicated that two patient samples were identified as brucella sp.Upon initial testing.Repeat testing for one of the isolates resulted in an identification of staphylococcus aureus.The customer performed alternate method testing by confirming purity and a positive staphaurex test.At the time of assessment, there is no indication or report from the customer that this event led to any adverse event related to any patient's state of health.
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Context: vitek ms.Mode : ivd.Kb version : 3.2 (cli us).Issue type : misidentification as brucella spp instead of staphylococcus aureus vitek ms result: - single choice to brucella ceti/pinnipedialis (twice).- single choice to staphylococcus aureus.Other method : staphaurex positive (in favor of s.Aureus) expected id: the expected identification has been defined as unknown because vitek ms is not considered as the identification reference method.Culture conditions: -culture media : blood agar - incubation: 18 hours - spotting tool: colibri (1st test) / pickme (retest).Issue date: (b)(6) 2023 before tuning -(b)(6)2023.Fine tuning date before the issue: (b)(6) 2023.Immediate action done by lcs.N/a.Impact & workaround there were no patient or operator death, no patient or operator harmed, no indirect harm patient reported, no patient harmed/treated incorrectly.However, based on vitek ms hazard definition bmx.1.009176 rev.4, the severity of an ¿erroneous test result - incorrect id result¿ for the patient is considered serious.An analysis has been done regarding the complaints recorded for a misidentification due to a non optimal spot preparation and a kb weakness.Refer to the file attached ¿(b)(4) - complaint analysis¿ for details.>>>probability as per bmx.1.009689 vitek ms v3.X risk management plan §6.3: improbable.The final risk is "irrelevant" following procedure 001622 rev 08.C.Investigation 1.Complaint trend analysis and device history record referring to (b)(4) - technical complaint trend analysis using the cstat application , there is no out-of-control alert, or a non-confirmed out-of-control alert in cstat for now.We checked the period from (b)(6) 2023 for the error code ivd mis-identification - (b)(4).2.Investigation fine tuning status good at the time of acquisition.Spot preparation quality the customer¿s spot preparation quality was not optimal.The calibrator and sample ¿all peaks¿ values were heterogeneous.It needs to be verified with the customer.Kb review the expected identification is unknown because no reference method was used to confirm the expected identification.Sample data analysis analyze of mzml sample files shows that the spectra (d1 and k1) which gave the misidentification to brucella spp have the lowest number of peaks (45 and 32 peaks) which is near the acceptable limit for giving an ¿identification¿ result or a ¿no identification¿ result (30).Moreover, this misidentification was obtained with a low identification score (-0.18) which is near the acceptable limit for giving an ¿identification¿ result or a ¿no identification¿ result (-0.4).This could be explained by a non-optimal spot preparation of the sample strain (culture, spot, different operator¿).It needs to be verified with the customer.By reprocessing the customer data with next vitek ms kb v3.3, spectra which gave misidentification results as brucella spp led to no identification.There is no more misidentification.Related to the misidentification as brucella, csn # (b)(4) was published about potential misidentification as brucella spp with kb v3.2.These incorrect organism identifications have always been seen so far in conjunction with degraded spectra (linked to a non-optimal spot preparation or a non-optimal fine-tuning).This issue was fixed with the new vitek ms kb v3.3.3.Root cause analysis -non optimal spot preparation -kb weakness linked with the bad quality of spectra.4.Corrective or preventive actions no capa number is needed.
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Intended use: vitek® ms is a mass spectrometry system using matrix-assisted laser desorption/ionization time of flight mass spectrometry (maldi-tof ms) for the identification of microorganisms cultured from human specimens.The vitek® ms system is a qualitative in-vitro diagnostic device indicated for use in conjunction with other clinical and laboratory findings to aid in the diagnosis of bacterial, yeast and mold infections.Issue description: a customer in the united states notified biomérieux of a misidentification of two (2) staphylococcus aureus patient isolates as brucella sp.Associated with vitek ms instrument - ref.(b)(4), serial number (b)(6).The customer indicated that two patient samples were identified as brucella sp.Upon initial testing.Repeat testing for one of the isolates resulted in an identification of staphylococcus aureus.The customer performed alternate method testing by confirming purity and a positive staphaurex test.At the time of assessment, there is no indication or report from the customer that this event led to any adverse event related to any patient's state of health.
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