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Physicians: .25 AMA PRA Category I CreditsTM
Family Physicians: .25 Prescribed credits
Nurse Practitioners: .25 Contact hours
Release Date: November 5, 2014
Expiration Date: November 5, 2015
Estimated Completion Time: 15 minutes
There is no fee for this activity.
To Receive Credit
In order to receive your certificate of participation, you should read the information about this activity, including the disclosure statements, review the entire activity, take the post-test, and complete the evaluation form. You may then follow the directions to print your certificate of participation. To begin, click the CME icon above.
Upon successful completion of this educational program, the reader should be able to:
1. Discuss the significance of this article as it relates to your clinical practice.
2. Be able to apply this knowledge to your patient's diagnosis, treatment and management.
Alan Ehrlich, MD
Assistant Professor in Family Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA; Executive Deputy Editor, DynaMed, Ipswich, Massachusetts, USA
Michael Fleming, MD, FAAFP
Assistant Clinical Professor of Family Medicine and Comprehensive Care, LSU Health Science Center School of Medicine, Shreveport, Louisiana, USA; Assistant Clinical Professor of Family Medicine, Department of Family and Community Medicine, Tulane University Medical School, New Orleans, Louisiana, USA; Chief Medical Officer, Amedisys, Inc. & Antidote Education Company
Dr. Ehrlich, Dr. Fleming, DynaMed Editorial Team members, and the staff of Antidote Education Company have disclosed that they have no relevant financial relationships or conflicts of interest with commercial interests related directly or indirectly to this educational activity.
No commercial support has been received for this activity.
ACCME: This activity has been planned and implemented in accordance with the Essential Areas and policies of the Accreditation Council for Continuing Medical Education through the joint sponsorship of Antidote Education Company and EBSCO Publishing. Antidote is accredited by the ACCME to provide continuing medical education for physicians. Antidote Education Company designates this enduring activity for a maximum of 0.25 AMA PRA Category 1 CreditsTM. Physicians should only claim credit commensurate with the extent of their participation in the activity.
AAFP: This enduring material activity, DynaMed EBM Focus Volume 9, has been reviewed and is acceptable for up to 15.25 Prescribed credits by the American Academy of Family Physicians. AAFP certification begins March 5, 2014. Term of approval is for one year from this date. Each EBM Focus is approved for .25 Prescribed credits. Credit may be claimed for one year from the date of each update. Physicians should claim only the credit commensurate with the extent of their participation in the activity.
AANP: This program is approved for 0.25 contact hour(s) of continuing education by the American Association of Nurse Practitioners. This program was planned in accordance with AANP CE Standards and Policies and AANP Commercial Support Standards.
Program ID: 1405237Y
Last week 509 journal articles were evaluated via DynaMed's Systematic Literature Surveillance and summaries of 274 articles were added to DynaMed content.
Based on criteria for selecting "articles most likely to change clinical practice," one article was selected by the DynaMed Editorial Team.
Angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) are commonly prescribed medications, often used for the treatment of hypertension, coronary artery disease, or chronic kidney disease. Both drug classes are associated with an increased risk of hyperkalemia (N Engl J Med 2004 Aug 5;351(6):585). Co-trimoxazole is a combination of trimethoprim and sulfamethoxazole and at doses used in clinical practice, trimethoprim is known to impair renal potassium elimination. Previous case-control studies have demonstrated that co-trimoxazole, which is often prescribed for urinary tract infections (UTI), may further increase the risk of hyperkalemia in elderly patients taking ACE inhibitors or ARBs (Arch Intern Med 2010 Jun 28;170(12):1045 full-text). A new case-control study evaluated the risk of sudden death with various antibiotics commonly prescribed for UTIs in this population.
A total of 1,027 patients at least 66 years old who had sudden death and 3,733 matched controls who did not have sudden death were evaluated. All patients were being treated with an ACE inhibitor or ARB and had received an antibiotic prescription within the previous 7 days. The antibiotics included co-trimoxazole, amoxicillin, ciprofloxacin, norfloxacin, or nitrofurantoin, and matching was by age, sex, and presence of chronic kidney disease or diabetes. Relative to amoxicillin, co-trimoxazole and ciprofloxacin were associated with increased risk of sudden death within 7 days of treatment (adjusted odds ratio [adjusted OR] 1.38, 95% CI 1.09-1.76) and (adjusted OR 1.29, 95% CI 1.03-1.62 respectively), while nitrofurantoin was associated with a decreased risk of sudden death (adjusted OR 0.64, 95% CI 0.46-0.88). In addition, at 14 days, co-trimoxazole was still associated with a significantly increased risk (adjusted OR 1.54, 95% CI 1.29-1.84), while the risk with ciprofloxacin was no longer significant (adjusted OR 1.18, 95% CI 1-1.39). There were no significant differences between either norfloxacin or nitrofurantoin compared to amoxicillin within 14 days of treatment.
The findings of this study suggest that co-trimoxazole may increase the risk of sudden death in elderly patients on ACE inhibitors or ARBs. The increase in risk of sudden death within 14 days is reported to correspond to approximately 3 sudden deaths per 1,000 co-trimoxazole prescriptions. There may also be some risk with ciprofloxacin although this is more likely to be mediated by the known QT prolongation effects of fluoroquinolones rather than via increased risk of hyperkalemia (Am J Emerg Med. 2012 Jan;30(1):252). Although the case-control design is a limitation, these findings support previous observational data showing an increased risk of hyperkalemia associated with co-trimoxazole in this patient population. Collectively, these data suggest that increased care or monitoring may be warranted when prescribing co-trimoxazole or ciprofloxacin, and also suggest nitrofurantoin may be preferred in elderly patients receiving ACE inhibitors or ARBs.
For more information, see the Co-trimoxazole topic in DynaMed.
The DynaMed editorial team is seeking specialist editors in the following fields: ENT, Gastroenterology, Hematology, Nephrology, Ophthalmology, Orthopedics, Surgery, and Vascular.
If interested, please send a recent copy of your CV to Rachel Brady at firstname.lastname@example.org.
PEMSoft Now Available For iPhone, iPad, and Android Devices
The PEMSoft Mobile app, a pediatric evidence-based point-of-care medical reference tool for hospitals, emergency departments, clinics, pediatric group practices, transport services, and medical schools, is now available from EBSCOHealth. Designed by pediatricians, emergency physicians and other medical specialists, the vast content in PEMSoft addresses the entire spectrum of neonatal, infant, child, adolescent and young adult health. PEMSoft authors adhere to a strict evidence-based editorial policy focused on systematic identification, evaluation and consolidation of practice-changing clinical literature.
The PEMSoft Mobile app includes explicit step-by-step emergency critical care procedures, information about common pediatric signs and symptoms and content covering pediatric injuries and management approaches. More than 3,000 evidence-based pediatric topics and a similar number of medical illustrations, clinical images and videos are also available via the mobile app.
The PEMSoft Mobile App is accessible from both Apple and Android devices. Visit the PEMSoft page for more information and a free mobile trial.
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