Antimicrobial-Resistant Bacteria and Prescription of Antibiotics at a Tertiary Care Hospital in Riyadh, Saudi Arabia.

Purpose The purpose of the study was to assess the bacterial resistance and annual antibiotic consumption at a tertiary care hospital in Riyadh, Saudi Arabia over a two-year period. Methods This retrospective cohort study was conducted at a tertiary care hospital in Riyadh, Saudi Arabia from January 1, 2016, to December 31, 2017. Results The results showed that there was no significant difference between 2016 and 2017 data regarding patient characteristics like bed occupancy rate, the average length of stay, and the number of admissions; the same was true for bacterial characteristics like the number of bacteria, percentage of isolates in the group, and multidrug resistance (MDR) percentage (p: >0.05). Between 2016 and 2017, there was a slight reduction in the sensitivity of Escherichia​​​ coli (E. coli) carbapenem-resistant Enterobacteriaceae (CRE) (97%, 86%) and Klebsiella pneumoniae (K. pneumoniae) CRE (80%, 76%) towards colistin. There was also a decrease in the sensitivity of Acinetobacter baumannii (A. baumannii) multidrug-resistant organism (MDRO) from 42% to 29% against tigecycline, but an increase in the sensitivity of K. pneumoniae CRE (33%, 50%) and E. coli CRE (76%, 82%). The percentage of MDR strains in gram-positive bacteria showed that more than half of Staphylococcus aureus (S. aureus) were methicillin-resistant (61%, 59%) in 2016 and 2017 respectively. There was a reduction in the percentage of MDR strains in some gram-negative bacteria like Pseudomonas aeruginosa (P. aeruginosa) MDRO (24%, 19%),E. coli extended-spectrum beta-lactamases (ESBL) (56%, 50%), E. coli CRE (4%, 1%), K. pneumoniae CRE (49%, 33%), A. baumannii CRE (90%, 76%), and Proteus mirabilis​​​​​​​ (P. mirabilis) ESBL (54%, 50%). Conclusion MDRO bacteria are very common in the hospital where the study was conducted. Immediate action is required to tackle this problem.