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Jan E Patterson

Publications and source records attributed to Jan E Patterson.

8 recordsLinked to original sources
PubMed2005

International clone of Neisseria meningitidis serogroup A with tetracycline resistance due to tet(B).

Thirteen Neisseria meningitidis clinical isolates from Africa, Asia, and the United States for which the tetracycline MICs were elevated (> or =8 microg/ml) were examined for 14 recognized resistance genes. Only the drug efflux mechanism encoded by tet(B) was detected. All isolates were in serogroup A, belonged to complex ST-5, and were closely related by pulsed-field gel electrophoresis analysis.

Electrophoresis, Gel, Pulsed-Field↗
PubMed2003

Extended-spectrum beta-lactamases.

Extended-spectrum beta-lactamases, most commonly found in Klebsiella pneumoniae and Escherichia coli, have increased markedly in the past decade, particularly in the intensive care unit setting. The problem has been significant in the United States but is even more prevalent in parts of Latin America and Asia. These plasmid-mediated beta-lactamases confer resistance to broad-spectrum beta-lactam antibiotics, including third- and fourth-generation cephalosporins, aztreonam, and extended-spectrum penicillins. Other resistances, such as aminoglycoside resistance and trimethoprim/sulfamethoxazole resistance, are often cotransferred on the same plasmid. Fluoroquinolone resistance is often associated, resulting in an organism that is resistant to most of the usual antimicrobial options. Although carbapenems are currently considered the drugs of choice for these pathogens, widespread use of these agents may lead to other resistance problems. Due to limited therapeutic options, prevention and control measures are important. Traditional infection control measures, such as contact precautions, are recommended to prevent spread in intensive care units. In addition, because this type of antimicrobial resistance appears to be particularly influenced by antibiotic utilization, antibiotic control measures may also be a very important intervention in limiting the spread of extended-spectrum beta-lactamases.

Journal Article↗
PubMed2003

In vitro activity of daptomycin against vancomycin-resistant enterococci of various Van types and comparison of susceptibility testing methods.

The increasing prevalence of vancomycin-resistant enterococcal (VRE) infections and the limited number of antimicrobial agents for their treatment emphasize a need for new, more effective agents. In this study, the in vitro activity of daptomycin was determined against a collection of 156 VRE from seven different institutions. Van types were characterized by PCR, and pulsed-field gel electrophoresis was performed to exclude isolates with >85% relatedness by dendrogram. Included were 126 Enterococcus faecium (109 vanA, 17 vanB) isolates, 5 Enterococcus faecalis (3 vanA, 2 vanB) isolates, 2 Enterococcus avium (vanA) isolates, 1 Enterococcus durans (vanA) isolate, 10 Enterococcus gallinarum (vanC1) isolates, and 12 Enterococcus casseliflavus (vanC2) isolates. MICs of daptomycin and five additional agents were determined by the NCCLS broth microdilution method with Mueller-Hinton (MH) broth containing supplemental calcium. MICs were also determined using two investigational E-test strip formulations, and disk diffusion testing was performed by the standard NCCLS method. The MIC of daptomycin at which 50% of the isolates tested were inhibited for this isolate collection was 4 microg/ml, and the MIC at which 90% of the isolates tested were inhibited was 8 microg/ml. Two isolates of vanA E. faecium were resistant to linezolid, and one isolate was resistant to quinupristin-dalfopristin. MICs of daptomycin determined by the E test with and without added calcium varied by 8- to 16-fold, and disk diffusion zones varied by 3 to 6 mm according to the calcium content of the commercial MH agar lots used in the study. This study has shown daptomycin to have good activity against a diverse collection of contemporary VRE isolates. However, improved standardization of the calcium content of MH agar will be important for reliable testing of daptomycin by clinical laboratories using either the E test or disk diffusion methods.

Anti-Bacterial Agents↗
PubMed2003

Clinical and microbiologic analysis of a hospital's extended-spectrum beta-lactamase-producing isolates over a 2-year period.

STUDY OBJECTIVE: To evaluate the microbiologic and clinical outcomes of patients with extended-spectrum beta-lactamase (ESBL)-producing isolates over a 2-year period. DESIGN: Retrospective analysis. SETTING: Tertiary care teaching hospital. PATIENTS: Twenty-one patients with cultures of confirmed ESBL-producing Escherichia coli, Klebsiella pneumoniae, or Klebsiella oxytoca. MEASUREMENTS AND MAIN RESULTS: Antimicrobial susceptibilities of piperacillin-tazobactam, cefotetan, carbapenems, aminoglycosides, fluoroquinolones, trimethoprim-sulfamethoxazole, and nitrofurantoin (nitrofurantoin for urinary isolates only) of confirmed ESBL producers at our institution were determined, as well as clinical outcomes of patients with ESBL-producing isolates. Microbiologic and medical records were reviewed for patient sex and age, antimicrobial susceptibilities, antimicrobial therapy, and clinical and microbiologic outcomes. From January 2000-December 2001, 31 isolates were confirmed as ESBL producers (6 E. coli, 11 K. pneumoniae, and 14 K. oxytoca). A statistically significant increase occurred over the 2-year period from 9 (0.6%) of 1414 isolates in 2000 to 22 (1.8%) of 1218 isolates in 2001 (p = 0.0055). All isolates were susceptible to carbapenems, and more than 88% were susceptible to amikacin, cefotetan, or nitrofurantoin. Less than 70% of isolates were susceptible to gentamicin, fluoroquinolones, piperacillin-tazobactam, or trimethoprim-sulfamethoxazole. All patients treated with a carbapenem experienced clinical cure. Piperacillin-tazobactam alone and in combination resulted in an overall clinical cure rate of 55%, with a 50% cure rate for isolates susceptible to piperacillin-tazobactam. All patients in whom antibiotic therapy failed had been treated with piperacillin-tazobactam or cefepime, either alone or in combination with a fluoroquinolone. CONCLUSION: Carbapenems remain the treatment of choice for ESBL-producing pathogens. Piperacillin-tazobactam and cefepime should not be routinely administered for the treatment of these organisms.

Anti-Bacterial Agents↗
PubMed2002

Disseminated phaeohyphomycosis: review of an emerging mycosis.

Disseminated phaeohyphomycosis is an uncommon infection caused by dematiaceous fungi, although the number of case reports about this infection has been increasing in recent years. A total of 72 cases are reviewed. Scedosporium prolificans is by far the most common cause. The presence of melanin in their cell walls may be a virulence factor for these fungi. The primary risk factor is decreased host immunity, although cases in apparently immunocompetent patients have been reported. Eosinophilia was seen in 11% of cases. Endocarditis is mostly reported on bioprosthetic valves, particularly those of porcine origin. The outcome of antifungal therapy remains poor, with an overall mortality rate of 79%. Special precautions taken for immunocompromised patients may help prevent exposure to fungi during the patients' period of greatest risk. The development of newer antifungal agents and combination therapy may hold promise in improving the management of these devastating infections in the future.

Adolescent↗