Effect of laboratory errors on the accurate and timely reporting of bloodstream and wound infections caused by extended spectrum beta-lactamase positive escherichia.coli.

Abstract

Production of extended spectrum beta lactamase enzymes is one of the common mechanisms of resistance of Escherichia coli to antibiotics, thus timely detection and reporting of this phenotype is very critical and crucial especially when it comes to blood stream and wound infections caused by this phenotype of E.coli. Errors that occur in the diagnostic cycle of the microbiology laboratory cause a delay in the timely and accurate reporting of extended spectrum beta lactamase positive E.coli isolated from bloodstream and wound infections which in turn results in to increased morbidity and mortality rates. Aim This study aimed to determine the effect of laboratory errors on the accurate and timely reporting of bloodstream and wound infections caused by extended spectrum beta lactamase positive Escherichia coli at Makerere University Clinical Microbiology Laboratory Methodology This study was a retrospective analysis of lab records for ESBL positive E. coli isolated from blood and pus samples received between the periods of January 2019 to March 2021 at the Makerere University Clinical Microbiology Laboratory Results For Bloodstream infections: Out of the 91 samples positive for E.coli received by the lab between the periods of January 2019 to March 2021, 50.55% (46) were ESBL positive while 46.15% (42) were ESBL negative. 3.30% (3) of the samples were not screened for ESBL production. Of the 91 request forms; majority 61(67.03%) had no errors while 30 (32.97%) had errors. In the lab bench books, all the 91samples (100%) gram stain, biochemical tests and antimicrobial susceptibility tests were done. 5(5.49%) and 2(2.2%) of the samples received by the lab were not cultured on BA and MAC respectively. For turnaround time of reporting ESBL positive E.coli blood stream infections., majority 63(69.23%) of the samples were processed within the stipulated time of 3-5 days as per the lab sops from the time of reception, however, a total of 28 blood cultures had a long turnaround time that is; 24(26.3%) took 6-8days and 4(4.4%) of samples took 9-11days. 16 of these were ESBL positive E.coli, of which only 4(25.0%) of them had pre-analytical errors and 3(18.75%) had analytical errors, which eventually affected the turnaround time for accurate and timely detection of ESBL positive E.coli in bloodstream infections. For wound infections: Out of 85 samples positive for E.coli received by the lab between the periods of January 2019- march 2021, 44.71% (38) were ESBL positive while 55.29% (47) were ESBL negative. Of the 85 request forms checked, majority 61 (71.76%) had no errors while the minority 24(28.24%) had errors. For All the 85 samples (100%) cultures on BA, MAC and chocolate agar, biochemical tests and antimicrobial susceptibility tests were done. Only 2(2.35%) were not gram stained. For Turnaround time of reporting ESBL positive E.coli wound infections, majority 52(61.18%) of the samples were processed within the stipulated time of 3-5 days as per the lab sops from the time of reception, while a total of 33 pus swabs had a long turnaround time that is; 18 (21.18%) took 6-8days, 3 (3.53%) took 9-11days and 12 (14.12%) took greater than 11days before results were sent out. 12 of these were ESBL positive E.coli, 5 (41.7%) of which had pre-analytical errors which could have potentially affected the turnaround time for accurate and timely detection of ESBL positive E.coli in bloodstream infections. None of these ESBL positive pus swabs had analytical errors