Description of Event or Problem · 1
OUR INSTITUTION HAS BEEN USING THE SOFIA FLUORESCENT IMMUNOASSAY ANALYZER (QUIDEL CORP., (B)(4)) AS OUR POINT-OF-CARE TEST (POCT) FOR INFLUENZA SINCE 2013. WE OBSERVED THAT (B)(6) PERCENT OF THE POSITIVE TESTS RESULTED AS INFLUENZA B, WHICH IS IN GREAT EXCESS OF THE CDC-PUBLISHED AVERAGE OF 4-9 PERCENT. BECAUSE WE SUSPECTED THE MAJORITY OF THE POCT INFLUENZA B RESULTS WERE FALSE POSITIVES, WE CONDUCTED A STUDY IN WHICH EVERY POSITIVE POCT TEST WAS IMMEDIATELY FOLLOWED UP WITH A SECOND SAMPLE ANALYZED BY OUR RESPIRATORY VIRUS PCR PANEL (ESENSOR, GENMARK DX, (B)(4)). OF (B)(6) POCT SPECIMENS POSITIVE FOR FLU B, (B)(6) PERCENT WERE NEGATIVE FOR THE PRESENCE OF ANY RESPIRATORY VIRUS BY PCR. ANOTHER (B)(6) PERCENT WERE POSITIVE ONLY FOR A NON-INFLUENZA VIRUS, SUCH AS RHINOVIRUS, ADENOVIRUS, ETC. THEREFORE, (B)(6) PERCENT OF THE POCT RESULTS FOR FLU B WERE FALSE POSITIVES. OF THE REMAINING RESULTS, (B)(6) PERCENT WERE FOUND TO BE FLU A (H1N1) BY PCR, AND ONLY (B)(6) OF THE (B)(6) PAIRED SPECIMENS WAS FOUND TO BE INFLUENZA B BY PCR. BECAUSE OUR CLINICAL PRACTICE DICTATES PRESCRIPTION OF NEURAMINIDASE INHIBITORS (PRINCIPALLY OSELTAMMIVIR) FOR FLU PTS, WE BELIEVE THAT POTENTIALLY (B)(6) PERCENT OF PTS WHO RECEIVED A POCT RESULT FOR INFLUENZA B WERE MISDIAGNOSED, AND INAPPROPRIATELY TREATED WITH A DRUG THEY DID NOT NEED. AS A RESULT OF THESE FINDINGS, WE WORKED WITH THE MANUFACTURER ON TWO OCCASIONS TO MAKE SURE THAT THE TEST WAS BEING PERFORMED CORRECTLY. DESPITE RE-TRAINING BY THE MANUFACTURER'S REPRESENTATIVES AS WELL AS OUR OWN STAFF, WE SAW NO REDUCTION IN THE PERCENT POSITIVITY FOR FLU B WITH THIS PRODUCT. AS A RESULT, WE INFORMED THE MANUFACTURER THAT WE WILL NO LONGER USE THIS PRODUCT AS OUR RAPID TEST FOR INFLUENZA, AND NOW SOLELY RELY UPON PCR.