Background: Antibiotic resistance is a worldwide problem. Prior studies on patterns of resistance in Zambia depended on laboratory methods that lacked standardization. UTH is a 1655 bed quaternary care hospital and the primary teaching hospital of Zambia. Since 2015, the microbiology laboratory has used Vitek 2 Compact (bioMerieux, Inc., France) for standardized detection of resistance.
Methods: We conducted a retrospective cross-sectional study of data collected on bacterial isolates analyzed from July 2015 to April 2017. We entered the data into WHONET 5.6 and aggregated it to develop hospital antibiograms. Due to high levels of resistance, we defined susceptible, intermediate, and resistant as >70%, 40-70%, and <40% of isolates sensitive to a drug respectively. To improve usability, a version replacing the percent susceptible with these categories was developed.
Results: We analyzed 2019 isolates to identify susceptibility patterns to commonly used antibiotics at UTH. Escherichia coli and Klebsiella pneumoniae, the most commonly isolated Gram-negative (GN) organisms, were resistant to most drugs including ceftriaxone, indicating high rates of extended-spectrum beta-lactamase production.
Methicillin resistant Staphylococcus aureus (MRSA) made up 37% of S.aureus isolates. MRSA and methicillin susceptible S. aureus were resistant to trimethoprim/sulfamethoxazole, a commonly used drug at UTH. Streptococcus pneumoniae was resistant to most drugs against which it was tested.
Conclusion: MDROs were common at UTH with carbapenems indicated for empiric GN therapy. Further research should assess the extent and depth of antibiotic resistance in Zambia. Antibiograms provide critical information for clinicians to strategically use antibiotics.
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K. Stafford, None
E. Heil, ALK-Abelló: Grant Investigator , Research grant .
L. Hachaambwa, Centers for Disease Control and Prevention (CDC): Cooperative Agreement to Institution , Financial support for the work described in this abstract was made possible by a cooperative agreement award from the Centers for Disease Control and Prevention (CDC) to the University of Zambia and to the University of Maryland School of Medicine. .
K. Yamba, None
M. Kalumbi, None
D. Patel, None
J. K. Johnson, Q-Linea: Investigator , Research grant . Applied Biocode: Investigator , Research grant .
C. Claassen, None