Jul 232014
 

Efficacy and Safety of Fosfomycin Plus Imipenem as Rescue Therapy for Complicated Bacteremia and Endocarditis due to Methicillin-Resistant Staphylococcus aureus: A Multi-center Clinical Trial.

Clin Infect Dis. 2014 Jul 21;

Authors: Del Río A, Gasch O, Moreno A, Peña C, Cuquet J, Soy D, Mestres CA, Suarez C, Pare JC, Tubau F, de la Maria CG, Marco F, Carratalà J, Gatell JM, Gudiol F, Miró JM, the FOSIMI investigators

Abstract
BACKGROUND:  There is an urgent need for alternative rescue therapies in invasive infections caused by methicillin-resistant Staphylococcus aureus(MRSA). We assessed the clinical efficacy and safety of the combination of fosfomycin and imipenem as rescue therapy for MRSA infective endocarditis and complicated bacteremia.
METHODS:  The trial was conducted between 2001 and 2010 in three Spanish hospitals. Adult patients with complicated MRSA bacteremia or endocarditis requiring rescue therapy were eligible for the study. Treatment with fosfomycin (2 g/6 h iv) plus imipenem (1 g/6 h iv) was started and monitored. The primary efficacy endpoints were the percentage of sterile blood cultures at 72 hours and the clinical success rate assessed at the test-of-cure visit (45 days after the end of therapy).
RESULTS:  The combination was administered in 12 patients with endocarditis, two with vascular graft infection, and two with complicated bacteremia. Therapy had previously failed with vancomycin in nine patients, daptomycin in two, and sequential antibiotics in five. Blood cultures were negative 72 hours after the first dose of the combination in all cases. The success rate was 69%, and only one out of five deaths was related to the MRSA infection. Although the combination was safe in most patients (94%), a patient with liver cirrhosis died of multi-organ failure secondary to sodium overload. There were no episodes of breakthrough bacteremia or relapse.
CONCLUSIONS:  Fosfomycin plus imipenem was an effective and safe combination when used as rescue therapy for complicated MRSA bloodstream infections and deserves further clinical evaluation as initial therapy in these infections.

PMID: 25048851 [PubMed - as supplied by publisher]

Link to Article at PubMed

Share


Jul 232014
 

A systematic review: Can one prescribe carbapenems to patients with IgE-mediated allergy to penicillins or cephalosporins?

Clin Infect Dis. 2014 Jul 21;

Authors: Kula B, Djordjevic G, Robinson JL

Abstract
BACKGROUND:  Cross-reactivity is anticipated between penicillins or cephalosporins and carbapenems as all have a beta lactam ring but the true incidence of IgE-mediated cross-reactivity is not known.
METHODS:  A systematic review was conducted to collect and combine all published data on children and adults reported to have a clinical history of IgE-mediated hypersensitivity to a penicillin and/or cephalosporin that were subsequently given a carbapenem. Reactions were classified as proven, suspected or possible IgE-mediated and non-IgE-mediated.
RESULTS:  Ten studies and 12 case reports fit the study criteria, describing 854 participants. For patients with previous proven, suspected or possible IgE-mediated penicillin reactions (N=838), the incidence of any type of suspected hypersensitivity reaction to a carbapenem was 36/838 (4.3%; 95% confidence interval 3.1- 5.9%) and the incidence of proven (1/838), suspected (0/838) or possible (19/838) IgE-mediated reactions was 20/838 (2.4%; 95% confidence interval 1.6- 3.7%). Of the sub-set of patients with positive penicillin skin tests (n=295), only one had a hypersensitivity reaction (0.3%; 95% confidence interval 0.06- 1.9%) and this was a possible IgE-mediated reaction. For patients with previous proven, suspected or possible IgE-mediated cephalosporin reactions (N=12), the incidence of any type of hypersensitivity reaction to a carbapenem was 3/12 (25%) including two non-IgE-mediated reactions and one possible IgE-mediated reaction.
CONCLUSIONS:  The cross-reactivity between penicillins and carbapenems for IgE-mediated reactions is very low but caution is still advised. Cross-reactivity rates may be higher between cephalosporins and carbapenems but minimal data is available.

PMID: 25048853 [PubMed - as supplied by publisher]

Link to Article at PubMed

Share


Jul 232014
 

The Predictive Utility of Prior Positive Urine Cultures.

Clin Infect Dis. 2014 Jul 21;

Authors: MacFadden DR, Ridgway JP, Robicsek A, Elligsen M, Daneman N

Abstract
BACKGROUND:  A patient's prior urine cultures are often considered when choosing empiric antibiotic therapy for a suspected urinary tract infection. We sought to evaluate how well a patient's previous urine cultures predict the identity and susceptibility of subsequent urine cultures.
METHODS:  We conducted a multi-national, multi-centre, retrospective cohort study, including 22,019 pairs of positive urine cultures from 4,351 patients, across two healthcare systems in Toronto, Ontario and Chicago, Illinois. We examined the probability of the same organism being identified from the same patient's positive urine culture as a function of time elapsed from the previous positive urine specimen; in cases where the same organism was identified we also examined the likelihood of the organism exhibiting the same or better antimicrobial susceptibility profile.
RESULTS:  At 4-8 weeks between cultures, correspondence of isolate identity was 57%(95%CI: 55-59%), and at >32 weeks was 49%(95%CI:48-50%), still greater than expected by chance(p<0.001). At 4-8 weeks, a same or better susceptibility profile was found in 83%(95%CI:81-85%) of isolate pairs, and at >32 weeks 75%(95%CI:73-77%), still greater than expected by chance(p<0.001). Despite high local rates of ciprofloxacin resistance in urine isolates across all patients (40%,95%CI 39.5-40.5%), ciprofloxacin resistance was less than 20% among patients with a prior ciprofloxacin sensitive organism and no subsequent fluoroquinolone exposure.
CONCLUSIONS:  A patient's prior urine culture results are useful in predicting the identity and susceptibility of a current positive urine culture. In areas of high fluoroquinolone resistance, Ciprofloxacin can be used empirically when prior urine culture results indicate a ciprofloxacin-susceptible organism and no history of intervening fluoroquinolone use.

PMID: 25048850 [PubMed - as supplied by publisher]

Link to Article at PubMed

Share


Jun 292014
 
Related Articles

Executive summary: practice guidelines for the diagnosis and management of skin and soft tissue infections: 2014 update by the infectious diseases society of america.

Clin Infect Dis. 2014 Jul 15;59(2):147-59

Authors: Stevens DL, Bisno AL, Chambers HF, Dellinger EP, Goldstein EJ, Gorbach SL, Hirschmann JV, Kaplan SL, Montoya JG, Wade JC

Abstract
A panel of national experts was convened by the Infectious Diseases Society of America (IDSA) to update the 2005 guidelines for the treatment of skin and soft tissue infections (SSTIs). The panel's recommendations were developed to be concordant with the recently published IDSA guidelines for the treatment of methicillin-resistant Staphylococcus aureus infections. The focus of this guideline is the diagnosis and appropriate treatment of diverse SSTIs ranging from minor superficial infections to life-threatening infections such as necrotizing fasciitis. In addition, because of an increasing number of immunocompromised hosts worldwide, the guideline addresses the wide array of SSTIs that occur in this population. These guidelines emphasize the importance of clinical skills in promptly diagnosing SSTIs, identifying the pathogen, and administering effective treatments in a timely fashion.

PMID: 24973422 [PubMed - in process]

Link to Article at PubMed

Share


Jun 292014
 
Related Articles

Previous Antibiotic Exposure and Antimicrobial Resistance in Invasive Pneumococcal Disease: Results from Prospective Surveillance.

Clin Infect Dis. 2014 Jun 27;

Authors: Kuster SP, Rudnick W, Shigayeva A, Green K, Baqi M, Gold WL, Lovinsky R, Muller M, Powis J, Rau N, Simor A, Walmsley S, Low DE, McGeer A, for the Toronto Invasive Bacterial Diseases Network

Abstract
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 three months affected antibiotic resistance in isolates causing invasive pneumococcal disease.
METHODS:  We conducted prospective surveillance for invasive pneumococcal disease in Toronto, Canada from 2002-2011. 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 4,062 (90%) episodes; 1,193 (29%) of episodes were associated with receipt of 1,782 antibiotic courses in the prior three months. Selection for antibiotic resistance was class specific. Time elapsed since most recent antibiotic was inversely associated with resistance (cephalosporins adjusted OR per day, 0.98; 0.96-1.00; P=.02; macrolides OR, 0.98; 0.96-0.99; P=.005; penicillins OR (log(days)), 0.62; 0.44-0.89; P=.009; fluoroquinolones profile penalized-likelihood OR (log(days)), 0.62; 95% CI, 0.39-1.04; 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.

PMID: 24973312 [PubMed - as supplied by publisher]

Link to Article at PubMed

Share


Jun 272014
 
Related Articles

Hypoglycemia in Patients Treated with Linezolid.

Clin Infect Dis. 2014 Jun 25;

Authors: Viswanathan P, Iarikov D, Wassel R, Davidson A, Nambiar S

Abstract
Hypoglycemia was not a previously known linezolid-associated adverse reaction. A case report describing symptomatic hypoglycemia in a linezolid recipient prompted a review of the FDA Adverse Event Reporting System which demonstrated a relationship between linezolid and hypoglycemia. A warning with this information was added to the linezolid package insert.

PMID: 24965346 [PubMed - as supplied by publisher]

Link to Article at PubMed

Share