We investigated the prevalence of β-lactamase genes and plasmid-mediated quinolone resistance (PMQR) determinants in 51 carbapenem-resistant Enterobacteriaceae (CRE) from five teaching hospitals in central China. The prevalence of carbapenem resistance in Enterobacteriaceae was 1·0% (51/5012). Of 51 CRE, 31 (60·8%) isolates were positive for one tested carbapenemase gene, while 10 (19·6%) were simultaneously positive for two tested carbapenemase genes. The positive rates of bla KPC-2, bla NDM-1, bla IMP-4, bla IMP-26 and bla IMP-8 were 54·9%, 17·6%, 11·8%, 11·8% and 3·9%, respectively. Of 10 CRE with two carbapenemase genes, three, five, one and one were positive for bla KPC-2 and bla IMP-4, bla KPC-2 and bla IMP-26, bla KPC-2 and bla IMP-8, and bla KPC-2 and bla NDM-1, respectively. Eight of nine bla NDM-1-positive isolates lacked carbapenemases by the modified Hodge test, while 27/28 isolates harbouring bla KPC-2 were positive for carbapenemases determined by this test; 41·2% of the CRE-positive isolates also harboured ESBL genes in various combinations (three and two positive for bla KPC-2 also carried bla DHA-1 and bla CMY-2). The positive rates of qnrS1, qnrA1, qnrB and aac-(6/)-Ib-cr in CRE were 25·5%, 9·8%, 23·5% and 15·7%, respectively. In particular, 7/9 isolates harbouring bla NDM-1 were positive for these quinolone resistance genes, of which five carried qnrS1 and two carried qnrS1 and qnrB4. All but two of 29 Klebsiella pneumoniae isolates were grouped into 20 clonal clusters by PFGE, with the predominant cluster accounting for four bla KPC-2-positive isolates distributed in the same hospital. We conclude that there is a high prevalence of bla NDM-1 and PMQR determinants in CRE isolates in central China. Multiple resistance determinants in various combinations co-exist in these strains and we report for the first time the co-existence of bla KPC-2 and bla IMP-26 in a strain of Klebsiella oxytoca.

Cryptococcosis is a globally distributed infectious fungal disease. However, much remains unknown about its molecular epidemiology in many parts of the world. In this study, we analyzed 86 clinical Cryptococcus neoformans isolates from 14 regions in Jiangxi Province in south central China. Each isolate was from a different patient and 35 of the 86 (40.7%) patients were infected with HIV. All strains belonged to serotype A and mating type α (MATα). Genotyping based on DNA sequences at seven nuclear loci revealed eight sequence types (STs) among the 86 isolates, including two novel STs that have not been reported from other parts of the world. ST5 was the dominant genotype and our comparative analyses showed that these genotypes in Jiangxi likely originated by dispersal from other regions within and outside of China and/or mutations from another genotype within Jiangxi. Though none of the isolates was resistant to the five tested antifungal drugs (flucytosine, amphotericin B, fluconazole, itraconazole, and voriconazole), obvious differences in their minimum inhibitory concentrations were observed, even among isolates of the same ST. Our results suggest that continuous monitoring should be conducted to understand the changing dynamics of C. neoformans in this and other regions.

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The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) often responsible for numerous hospital-associated outbreaks has become an important public health problem. From January 2013 to February 2014, a total of 41 non-duplicate K. pneumoniae isolates with carbapenem resistance, were collected at a tertiary teaching hospital in Nanchang, central China. Among 41 K. pneumoniae isolates, 28 were isolated from hospitalized patients including 19 from the patients in surgery intensive care unit (SICU) and 13 were isolated from ventilators. Twenty-four of 28 patients infected by CRKP have been submitted to mechanical ventilation using ventilator. More than 95% of the CRKP isolates were resistant to 13 antimicrobials tested. All CRKP isolates were confirmed as carbapenemase producer and were positive for blaKPC-2, with one positive for both blaKPC-2 and blaNDM-1. All carbapenemase-producing isolates harbored at least one of extended spectrum β-lactamase genes tested, among which 95.1% (39/41) of the tested isolates were found to harbor both blaCTX-M-24 and blaKPC-2, Of note, one isolate harbored simultaneously two carbapenemase genes (blaKPC-2 and blaNDM-1) and two ESBL genes (blaCTX-M-3 and blaTEM-104). To the best of our knowledge, coexistence of blaKPC-2 and blaCTX-M-24 in one isolate is first reported. MLST results showed that 41 CRKP isolates belonged to four sequence types (STs) including ST11, novel ST1854, novel ST1855, and ST1224. PFGE results displayed three PFGE clusters. Thirty-eight ST11 CRKP isolates (92.7%, 38/41) including all 13 isolates from ventilators and 25 isolates from patients from seven wards (18 from SICU) belonged to same PFGE cluster, indicating these isolates were clonally related. Fifteen isolates have an identical undistinguished pattern (100% similarity) forming a single clonal population. Moreover, this clone was exclusively linked to the cases attended in SICU and linked to the Ventilators. Additionally, the other SICU cases were linked to closely related clones (similarity greater than 95%). These data indicated that the occurrence of a clonal outbreak associated with ventilators has been found. In conclusion, outbreak by ventilator-associated ST11 K. pneumoniae with co-production of CTX-M-24 and KPC-2 is found in a SICU of a tertiary teaching hospital in central China.

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