Chronic sinusitis-associated antrolith.

An antrolith is a calcified mass found in the nasal cavity or sinus, usually maxillary, described in literature as a rare phenomenon. Its presenting symptoms are variable and include symptoms associated with chronic sinusitis. We describe a 66 year old man with chronic sinusitis who presented with facial pain and epistaxis and upon further evaluation was found to have an antrolith of the left maxillary sinus.

Effect of Porins and blaKPC Expression on Activity of Imipenem with Relebactam in Klebsiella pneumoniae: Can Antibiotic Combinations Overcome Resistance?

Imipenem with relebactam is a novel ß-lactam-ß-lactamase inhibitor that has activity against most KPC-producing Enterobacteriaceae. Using 10 isolates of KPC-possessing Klebsiella pneumoniae, we assessed the relationship between imipenem-relebactam minimum inhibitory concentrations (MICs) and mechanisms known to contribute to antimicrobial resistance. The effect of adding a second agent was assessed by time-kill experiments. Mutations affecting the genes encoding porins ompK35 and ompK36 and identification of ß-lactamases were assessed by PCR. Expression of blaKPC and acrB was assessed by real-time reverse-transcriptase (RT)-PCR, and production of OmpK36 by SDS-PAGE. Time-kill studies were performed using combinations of imipenem-relebactam with polymyxin B, amikacin, or tigecycline. Seven isolates having a disruption in a single porin, or in neither porin, remained susceptible to imipenem-relebactam. The addition of a second agent did not improve the activity of imipenem-relebactam for these isolates, although the addition of tigecycline was antagonistic for three isolates. Three isolates had major disruptions in both ompK35 and ompK36 that correlated with reduced activity of imipenem-relebactam (MICs 2/4, 8/4, and 512/4 µg/mL). Two of these isolates also had overexpression of blaKPC, including the isolate with the highest MIC. These isolates were also resistant to polymyxin B and amikacin. The addition of amikacin provided both synergistic and bactericidal activity for the two more resistant isolates. The activity of imipenem-relebactam against K. pneumoniae is affected by major disruptions of both ompK35 and ompK36 and by expression of the KPC gene. Combining imipenem-relebactam with an aminoglycoside may be a promising approach for isolates with reduced susceptibility to imipenem-relebactam.

Activity of Ceftazidime-Avibactam Against Clinical Isolates of Klebsiella pneumoniae, Including KPC-Carrying Isolates, Endemic to New York City.

In this report, we examined the (1) activity of ceftazidime-avibactam against clinical isolates Klebsiella pneumoniae, including those harboring blaKPC, (2) potential mechanisms leading to reduced susceptibility, and (3) activity of ceftazidime-avibactam when combined with other agents. Of 802 carbapenem-resistant isolates of K. pneumoniae gathered from New York City from 1999 to 2014, all were susceptible to ceftazidime-avibactam. Minimum inhibitory concentrations (MICs) were higher in isolates with K. pneumoniae, with the carbapenemase (KPC)-3 (compared to KPC-2), and those with a frameshift mutation in ompK35. MICs did not appear to be affected by changes in ompK36 or by expression of acrB. Time-kill experiments demonstrated synergy between either polymyxin B or amikacin and ceftazidime-avibactam in a minority of isolates. In conclusion, ceftazidime-avibactam is active against K. pneumoniae, including blaKPC isolates, in our region, but activity is affected by KPC subtype and by mutations in ompK35. Synergy can occur when combined with polymyxin B or amikacin, but is unpredictable.

Administration of a survey to evaluate the attitudes of house staff physicians towards antimicrobial resistance and the antimicrobial stewardship programme at a community teaching hospital.

Antimicrobial stewardship programmes (ASPs) are used in numerous institutions in an effort to promote safe and effective antimicrobial use. The objectives of this study were to (i) assess physicians' perceptions, attitudes and knowledge about antimicrobial use, resistance and the ASP at The Brooklyn Hospital Center (TBHC) and (ii) measure physicians' beliefs and attitudes to the current system of prior authorisation of antimicrobials. A 75-item, anonymous, voluntary, traditional paper and pencil survey was distributed to resident physicians at TBHC. Multiple-choice, 5-point Likert scale and knowledge-based questions were utilised. Of the 261 residents, 129 (49%) completed the survey. The respondents significantly believed that antibiotics are overused more frequently nationally vs. locally [117/129 (91%) vs. 91/129 (71%); P=0.0001]. Although 49% (63/129) felt that other providers overprescribe antibiotics, only 26% (34/129) agreed that they themselves were contributing to the current problem (P=0.0003). Fifty-seven percent of respondents agreed that individual patient care is improved by having an antibiotic approval programme; however, 45% of respondents reported that the antibiotic approval programme limits their autonomy in choosing antibiotics. Compared with surgical residents, medical residents were more likely (33% vs. 13%; P=0.02) to feel that the antibiotic approval programme forced them to choose an inappropriate antibiotic. On the antibiotic knowledge assessment segment of the survey, there was no difference in score when stratified by specialty or years of postgraduate training. Based on the survey results, house staff are supportive of antimicrobial stewardship and feel that the ASP is valuable for patient care.