Study for Monitoring Antimicrobial Resistance Trends (SMART) in Australia and New Zealand (ANZ), 2016-2017 (#384)
SMART has monitored the in vitro susceptibility patterns of clinical Gram-negative bacilli to antimicrobial agents in ANZ from intra-abdominal infections since 2002, urinary tract infections since 2009 and respiratory infections since 2015. This update includes suceptibility data from 2016-2017.
The top three pathogens for intra-abdominal infections (n=7112) were Escherichia coli (48%), Klebsiella pneumoniae (12%) and Pseudomonas aeruginosa (11%). Of these the most common sources were peritoneal fluid (36%), abscess (16%) and gallbladder (12%). The top three pathogens for patients with urinary infections (n=3530) were E. coli (57%), K. pneumoniae (14%) and P. aeruginosa (8%), and the most common sources were urine (93%) and kidney (6%). The top three pathogens from patients with respiratory infections (n=2085) were P. aeruginosa (35%), E. coli (14%), and K. pneumoniae (13%). Of these the most common sources were sputum (63%), endotracheal aspirate (27%) and bronchoalveolar lavage (9%). Excluding sputum isolates from respiratory samples the prevalence was P. aeruginosa (23%), K. pneumoniae (16%) and E. coli (15%).
Amongst 2833 Enterobacteriaceae from 2016-2017, rank order non-susceptibility (NS) was ceftriaxone (CRO, 20%), ceftazidime (CAZ, 18%), ciprofloxacin (CIP, 15%), piperacillin/tazobactam (PTZ, 13%), cefepime (FEP, 13%) and ceftolozane/tazobactam (C/T, 8%)†. NS to imipenem (IPM), meropenem (MEM) and amikacin (AMK) was ~1%. Of 212 CRO NS E. coli isolates from 2016-2017, rank order NS was PTZ (25%), C/T (17%), ETP (4%), AMK (7%), colistin (COL, 1%) and MEM or IPM (0%). Molecular analysis of E. coli (n=75) and K. pneumoniae (n=34) from 2016 confirms predominance of CTX-M-type extended-spectrum β-lactamases.
Amongst 727 Pseudomonas aeruginosa from 2016-2017, rank order NS was CIP (18%), PTZ (15%), FEP (13%), CAZ (13%), MEM (11%) and IPM (10%). NS to C/T and colistin was ≤ 3%. Of 81 MEM NS isolates, rank order NS was IPM (79%), TZP (60%), FEP (54%), CIP (49%), CAZ (48%), AMK (19%), C/T (17%) and COL (1%). Of 93 CAZ NS isolates, rank order NS was TZP (89%), FEP (69%), MEM (42%), CIP (39%), IPM (38%), C/T (22%), AMK (15%) and COL (1%). Molecular analysis of P. aeruginosa (n=67) isolates from 2016 identified a single acquired carbapenemase.
† EUCAST criteria