MICROSTREP PLUS1 PANEL

Additional Manufacturer Narrative

IT IS UNCLEAR WHETHER THE AVAILABLE INFORMATION REASONABLY SUGGESTS THAT THE MICROSTREP PLUS 1 (MSP1) PANEL HAS MALFUNCTIONED, THUS RESULTING IN MIC DISCREPANCY FOR PENICILLIN. THE DATA PROVIDED BY THE CUSTOMER WAS REVIEWED BY THE MANUFACTURER. RAW AND PROCESSED DATA FOR ALL THE CONVENTIONAL PANELS WAS TYPICAL, REPEATABILITY OF STERILE WELLS WAS GOOD, NO TRAILING INDICATED. THE MSP1 PANELS HAD SLIGHTLY ELEVATED PROCESSED VALUES ON THE RIGHT SIDE OF THE PANEL HOWEVER THESE DID NOT SEEM TO IMPACT READS. THE WELL AT THE END OF THE PENICILLIN DILUTION SERIES DID NOT HAVE AN ELEVATED VALUE. THIS IS BEING REPORTED BECAUSE STREPTOCOCCUS PNEUMONIAE IS KNOWN TO BE THE CAUSE OF SERIOUS INFECTIONS, WITH PENICILLIN BEING THE DRUG OF FIRST CHOICE FOR ISOLATES SUSCEPTIBLE OR INTERMEDIATE TO PENICILLIN IN NON-PENICILLIN ALLERGIC PATIENTS. THERE IS A HIGH RISK OF TREATMENT FAILURE IF A PENICILLIN RESISTANT ISOLATE IS REPORTED SUSCEPTIBLE. THE ISOLATE WAS RETURNED TO THE MANUFACTURER FOR TESTING SUPPLEMENTAL REPORT WILL BE FILED WITH THE INVESTIGATION RESULTS. (B)(4).

Description of Event or Problem

IT WAS REPORTED THAT AN ISOLATE OF STREPTOCOCCUS PNEUMONIA FROM THE AMERICAN PROFICIENCY INSTITUTE (API) PROFICIENCY SURVEY RESULTED IN AN MIC DISCREPANCY FOR PENICILLIN. THREE SEPARATE TESTS WERE PERFORMED USING THE MICROSCAN MICROSTREP 1 PANEL. INITIAL TEST RESULTS SHOWED PENICILLIN AS SUSCEPTIBLE AND SUBSEQUENT REPEAT TESTS AS INTERMEDIATE. THE API PROFICIENCY SURVEY EXPECTED RESULT WAS RESISTANT. IT WAS REPORTED THAT PANEL QC WAS IN RANGE BEFORE AND AFTER THE REPORTED INCIDENT. THERE WERE NO UNDERLINED VALUES ON THE QC DIAGNOSTIC REPORT OBSERVED. THERE WAS NO PATIENT INVOLVED AS THIS WAS A PROFICIENCY SURVEY.

Additional Manufacturer Narrative

THE SAME ISOLATE FROM API WAS SUBMITTED TO BECKMAN COULTER FOR INVESTIGATION. BECKMAN COULTER TESTING LAB SUPPORT DUPLICATED THE FALSE SUSCEPTIBLE RESULTS ON BOTH FROZEN AND DRIED MICROSTREP2 PANELS. TESTING ALSO DOCUMENTED THAT THE ORGANISM WAS NOT AUTOLYSING WHICH COULD HAVE CONTRIBUTED TO THE OBSERVED FALSE SUSCEPTIBLE RESULTS. ADDITIONAL TESTING DETERMINED THAT THE ORGANISM DID EXPRESS THE RESISTANCE TO PENICILLIN WHEN THE PANELS WERE INCUBATED IN CO2 AND WHEN THE ORGANISM WAS SUBCULTURED MULTIPLE TIMES PRIOR TO TESTING USING THE SAME TEST METHOD AS THE INITIAL TESTING THAT YIELDED SUSCEPTIBLE RESULTS. THIS INFORMATION SUGGESTS THIS ISOLATE MAY REQUIRE SPECIAL HANDLING WHEN PERFORMING SUSCEPTIBILITY TESTING. (B)(6).