Clearance of carbapenemase-producing Enterobacteriaceae (CPE) carriage: a comparative study of NDM-1 and KPC CPE.

OBJECTIVES: The aim of this study was to compare clearance rates and related characteristics of patients carrying KPC-producing carbapenemase-producing Enterobacteriaceae (CPE) with those of patients carrying NDM-1-producing CPE. METHODS: From November 2010 to October 2016, consecutive patients whose clinical or surveillance cultures yielded CPE were prospectively identified and followed in a 2700-bed tertiary referral hospital. CPE control protocols included strict single-room isolation, contact precautions and weekly surveillance cultures. CPE clearance was defined as three or more consecutive CPE-negative cultures without relapse. We compared patients carrying NDM-1 CPE and KPC and those with and without clearance. The time to CPE clearance or discharge was assessed using the Kaplan-Meier method and NDM-1 CPE and KPC CPE groups were compared. RESULTS: A total of 147 patients carrying CPE, 106 with NDM-1 and 41 with KPC, were included in the study. At the time of hospital discharge, 12 of the 106 patients carrying NDM-1 CPE were clear of CPE, whereas none of the KPC CPE patients were (NDM-1, 11.3% (12/106) versus KPC, 0% (0/41), p 0.02). There was no significant association between CPE clearance and factors such as an immunocompromised condition, antibiotic usage, or species of colonizing organism. Among 40 patients who were readmitted, CPE non-clearance was significantly higher in patients carrying KPC CPE (NDM-1, 36.7% (11/30) versus KPC, 80.0% (8/10), p 0.03). CONCLUSIONS: Compared with NDM-1 CPE patients, patients carrying KPC CPE had a significantly lower probability of clearance during hospitalization. Furthermore, KPC CPE carriage persisted for a substantial period of time following patient discharge.

Phenotypic changes of methicillin-resistant Staphylococcus aureus during vancomycin therapy for persistent bacteraemia and related clinical outcome.

Persistent bacteraemia (PB) due to methicillin-resistant Staphylococcus aureus (MRSA) that fails to respond to glycopeptide therapy is a well-documented clinical problem. There are limited data on changes in agr functionality, vancomycin susceptibility and heteroresistance during MRSA PB. Thus, the frequency of these changes and their clinical significance remain unclear. Only patients with MRSA PB (≥7 days) from a prospective cohort of S. aureus bacteraemia were included. We collected isogenic paired strains and compared vancomycin MIC, vancomycin heteroresistance, and agr functionality between initial and final blood isolates. We also assessed the clinical outcome. A total of 49 patients had MRSA PB over 22 months. Bacteraemia persisted for a median of 13 days and most patients (98%) received glycopeptide as initial therapy. Among 49 isogenic pairs, only one pair showed a vancomycin MIC increase ≥2-fold by broth microdilution method, and only seven (14%) by E-test. Significant portions of initial isolates had vancomycin heteroresistance (49%) and agr dysfunction (76%). Development of vancomycin heteroresistance during PB occurred in four (16%) among 25 initial vancomycin-susceptible isolates, and acquisition of agr dysfunction occurred in two (16%) among 12 initial agr-functional isolates. Changes in the opposite direction occasionally occurred. These phenotypic changes during PB were not associated with mortality, whereas agr dysfunction of the initial isolates was significantly associated with mortality. During MRSA PB, phenotypic changes of MRSA isolates occurred occasionally under prolonged vancomycin exposure but were not significantly associated with clinical outcome. In contrast, initial agr dysfunction could be a predictor for mortality in MRSA PB.

Diagnostic sensitivity of culture and drug resistance patterns in Korean patients with intestinal tuberculosis.

SETTING: It is challenging to differentiate between intestinal tuberculosis (ITB) and Crohn's disease in areas where TB is still prevalent. The use of diagnostic tools and verifying the drug resistance patterns of ITB can be helpful for its correct diagnosis. OBJECTIVE: To determine the diagnostic sensitivity of a culture assay using colonoscopic biopsy specimens and the drug resistance patterns of Mycobacterium tuberculosis isolated from ITB. DESIGN: Data from 400 patients diagnosed with ITB were retrospectively analysed. RESULTS: Of the 400 patients, 170 (42.5%) were males; the median age at diagnosis was 40 years. The sensitivity of culture was 44.1% (145/329). Resistance to at least one anti-tuberculosis drug was identified in 13 (17.6%) and multidrug-resistant TB (MDR-TB) was diagnosed in two (2.7%) of the 74 patients for whom drug susceptibility testing was performed. Including M. tuberculosis isolated from respiratory specimens, the proportion of MDR-TB was 4.4% (5/113); previous anti-tuberculosis treatment was an independent risk factor for MDR-TB (26.7% vs. 1.0%, P < 0.01). CONCLUSION: Culture of colonoscopic biopsy specimens shows substantial diagnostic sensitivity; the frequency of MDR-TB is higher in previously treated cases than in new cases.

Study to compare the efficacy and safety of fluconazole cream with flutrimazole cream in the treatment of superficial mycosis: a multicentre, randomised, double-blind, phase III trial.

Fluconazole, which is a drug of the azole family, is safely used in systemic treatment of oral and intravenous injection, but it is difficult to use fluconazole as a topical application because of its large molecular weight and strong hydrophilic property. This study is a multicentre, double-blind, randomised, non-inferiority study to compare the antifungal effect and safety of fluconazole cream 0.5% and 1% with flutrimazole cream 1% in superficial mycosis. A total of 162 subjects selected to participate in this study were equally divided into three groups and assigned to be given fluconazole cream 0.5%, fluconazole cream 1%, and flutrimazole cream 1% in the ratio of 1 : 1. The primary index of drug efficacy was determined by complete mycological cure in which no fungus was detected on KOH smear test 4 weeks after application of fluconazole. The secondary index of efficacy was defined as complete mycological cure 4 weeks after the application of fluconazole, improvement of clinical symptoms and overall effectiveness assessed by the research staff. According to this study, on comparing the efficacy of cure of superficial dermatomycosis after 4 weeks of application, both fluconazole 0.5% and fluconazole 1% cream were found to be equally effective and non-inferior to flutrimazole 1% cream. Given the effectiveness and safety of the drug, both fluconazole 0.5% and 1% cream might be said to be optimal concentration in the treatment of superficial dermatomycosis.

Impact of previous use of antibiotics on development of resistance to extended-spectrum cephalosporins in patients with enterobacter bacteremia.

This retrospective study was conducted to determine the risk factors for resistance to extended-spectrum cephalosporins (ESCs) and to examine the influence of previous use of an aminoglycoside with an ESC on resistance to ESCs in patients with Enterobacter bacteremia from January 1991 through December 2000. A total of 423 episodes of Enterobacter bacteremia among 414 patients were documented during the 10-year study period. Three hundred thirty-two (78%) isolates were Enterobacter cloacae, 72 (17%) Enterobacter aerogenes, and 19 (4%) other Enterobacter species. Causative isolates exhibited resistance to ESCs in 225 episodes and susceptibility in 198 episodes. Nosocomial acquisition was an independent risk factor for resistance to ESCs (odds ratio [OR], 3.4; 95% confidence interval [95%CI], 1.7-6.8). The median number of antibiotics used was significantly greater in cases caused by resistant isolates than in cases caused by susceptible isolates (OR, 1.8; 95%CI, 1.2-2.6). Resistance to ESCs was associated with previous use of any ESC (OR, 5.0; 95%CI, 2.5-10.2). The proportion of resistant episodes in patients treated previously with an aminoglycoside plus an ESC was not different from that in patients treated with an ESC alone. In conclusion, previous use of ESCs was associated with resistance to ESCs in patients with Enterobacter bacteremia; moreover, previous use of an aminoglycoside with an ESC did not significantly decrease the risk of resistance to ESCs.

Vancomycin-intermediate Staphylococcus aureus in Korea.

Recent reports on some methicillin-resistant Staphylococcus aureus (MRSA) with reduced susceptibility to vancomycin have been a major concern in Korea because of the widespread use of vancomycin due to a high prevalence of MRSA in the country. We describe a 45-year-old man with long-standing pelvic abscess due to MRSA. In spite of vancomycin and teicoplanin treatment for a long period of time, the patient died from MRSA sepsis. The blood culture isolate of MRSA exhibited reduced susceptibility to vancomycin (MIC, 8 microg/ml). This is the first report of a vancomycin-intermediate S. aureus case from Korea.