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Medline ® Abstracts for References 34,35

of 'Treatment of community-acquired pneumonia in adults who require hospitalization'

Risk factors for drug-resistant pathogens in community-acquired and healthcare-associated pneumonia.
Shindo Y, Ito R, Kobayashi D, Ando M, Ichikawa M, Shiraki A, Goto Y, Fukui Y, Iwaki M, Okumura J, Yamaguchi I, Yagi T, Tanikawa Y, Sugino Y, Shindoh J, Ogasawara T, Nomura F, Saka H, Yamamoto M, Taniguchi H, Suzuki R, Saito H, Kawamura T, Hasegawa Y
Am J Respir Crit Care Med. 2013;188(8):985.
RATIONALE: Identification of patients with drug-resistant pathogens at initial diagnosis is essential for treatment of pneumonia.
OBJECTIVES: To elucidate clinical features of community-acquired pneumonia (CAP) and healthcare-associated pneumonia (HCAP), and to clarify risk factors for drug-resistant pathogens in patients with CAP and HCAP.
METHODS: A prospective observational study was conducted in hospitalized patients with pneumonia at 10 institutions in Japan. Pathogens identified as not susceptible to ceftriaxone, ampicillin-sulbactam, macrolides, and respiratory fluoroquinolones were defined as CAP drug-resistant pathogens (CAP-DRPs).
MEASUREMENTS AND MAIN RESULTS: In total, 1,413 patients (887 CAP and 526 HCAP) were analyzed. CAP-DRPs were more frequently found in patients with HCAP (26.6%) than in patients with CAP(8.6%). Independent risk factors for CAP-DRPs were almost identical in patients with CAP and HCAP. These included prior hospitalization (adjusted odds ratio [AOR], 2.06; 95% confidence interval [CI], 1.23-3.43), immunosuppression (AOR, 2.31; 95% CI, 1.05-5.11), previous antibiotic use (AOR, 2.45; 95% CI, 1.51-3.98), use of gastric acid-suppressive agents (AOR, 2.22; 95% CI, 1.39-3.57), tube feeding (AOR, 2.43; 95% CI, 1.18-5.00), and nonambulatory status (AOR, 2.45; 95% CI, 1.40-4.30) in the combined patients with CAP and HCAP. The area under the receiver operating characteristic curve for counting the number of risk factors was 0.79 (95% CI, 0.74-0.84).
CONCLUSIONS: The clinical profile of HCAP was different from that of CAP. However, physicians can predict drug resistance in patients with either CAP or HCAP by taking account of the cumulative number of the risk factors. Clinical trial registered with https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&type=summary&recptno=R000004001&language=E ; number UMIN000003306.
1 Institute for Advanced Research, Nagoya University, Nagoya, Japan.
Previous antibiotic exposure and antimicrobial resistance in invasive pneumococcal disease: results from prospective surveillance.
Kuster SP, Rudnick W, Shigayeva A, Green K, Baqi M, Gold WL, Lovinsky R, Muller MP, Powis JE, Rau N, Simor AE, Walmsley SL, Low DE, McGeer A, Toronto Invasive Bacterial Diseases Network
Clin Infect Dis. 2014 Oct;59(7):944-52. Epub 2014 Jun 27.
BACKGROUND: Estimating the risk of antibiotic resistance is important in selecting empiric antibiotics. We asked how the timing, number of courses, and duration of antibiotic therapy in the previous 3 months affected antibiotic resistance in isolates causing invasive pneumococcal disease (IPD).
METHODS: We conducted prospective surveillance for IPD in Toronto, Canada, from 2002 to 2011. Antimicrobial susceptibility was measured by broth microdilution. Clinical information, including prior antibiotic use, was collected by chart review and interview with patients and prescribers.
RESULTS: Clinical information and antimicrobial susceptibility were available for 4062 (90%) episodes; 1193 (29%) of episodes were associated with receipt of 1782 antibiotic courses in the prior 3 months. Selection for antibiotic resistance was class specific. Time elapsed since most recent antibiotic was inversely associated with resistance (cephalosporins: adjusted odds ratio [OR]per day, 0.98; 95% confidence interval [CI], .96-1.00; P = .02; macrolides: OR, 0.98; 95% CI, .96-.99; P = .005; penicillins: OR [log(days)], 0.62; 95% CI, .44-.89; P = .009; fluoroquinolones: profile penalized-likelihood OR [log(days)], 0.62; 95% CI, .39-1.04; P = .07). Risk of resistance after exposure declined most rapidly for fluoroquinolones and penicillins and reached baseline in 2-3 months. The decline in resistance was slowest for macrolides, and in particular for azithromycin. There was no significant association between duration of therapy and resistance for any antibiotic class. Too few patients received multiple courses of the same antibiotic class to assess the significance of repeat courses.
CONCLUSIONS: Time elapsed since last exposure to a class of antibiotics is the most important factor predicting antimicrobial resistance in pneumococci. The duration of effect is longer for macrolides than other classes.
Mount Sinai Hospital, Toronto, Canada University Hospital Zurich and University of Zurich, Switzerland.