New research presented at the 51st Interscience Conference on Antimicrobial Agents and Chemotherapy, or ICAAC, from September 17-20, 2011 in Chicago addressed important issues on antimicrobial therapies and infectious diseases. The features below highlight just some of the studies that emerged from the meeting.
» Bloodstream Infections & Colorectal Cancer Screening
» S. Aureus Implicated in Many Skin Infections
» Rapid Clostridium difficile Diagnosis Improves Patient Care
» Antibiotic Prescription Trends
» Maggots Heal Difficult Wounds in Diabetics
» Hospital Privacy Curtains Frequently Contaminated
Bloodstream Infections & Colorectal Cancer Screening
The Particulars: Previous research has established a link between colorectal cancer and bloodstream infections with certain bacteria.
Data Breakdown: In a study of 1.2 million people, researchers detected 10,121 bloodstream infections and made 3,859 colorectal cancer diagnoses, and 71 colorectal cancer diagnoses were made during the year following infection. The risk of a colorectal cancer diagnosis in the year following bacterial bloodstream infections was 14 times that of the “normal” population. Anaerobic bacteria of the gut were associated with a 115 times greater risk of a colorectal cancer diagnosis.
Take Home Pearl: Patients with bloodstream infections should be targeted for colorectal cancer screening due to their increased risk for the disease within 1 year.
S. Aureus Implicated in Many Skin Infections [back to top]
The Particulars: Much is known about the causative pathogens in skin and skin-structure infections, but little is known specifically about acute bacterial skin and skin-structure infections (ABSSSI).
Data Breakdown: An analysis of a large, multihospital database found that the most common cause of ABSSSIs among patients hospitalized in the United States appeared to be Staphylococcus aureus. Approximately 60% of patients with ABSSSI had S. aureus infections, almost half of whom had infections due to MRSA. Of those admitted to a hospital with an ABSSSI, 34% had one or more ESKAPE (enterococcus faecium, MRSA, Klebsiellapneumonia, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter species) pathogens.
Take Home Pearl: The most common cause of ABSSSI among patients hospitalized in the U.S. appears to be S. aureus.
Rapid Clostridium difficile Diagnosis Improves Patient Care [back to top]
The Particulars: A rapid diagnosis is crucial to prompt, appropriate therapy for Clostridium difficile-induced diarrhea and the implementation of infection control measures. Traditional diagnostics have a turnaround for results of about 2.5 days. Polymerase chain reaction (PCR) technology allows for same-day diagnosis of C. difficile.
Data Breakdown: A study was conducted in two hospitals comparing PCR with the traditional cell cytotoxin neutralization assay. It found that use of the PCR assay was linked to decreased isolation time by 3 days per patient at one hospital and by 4 days per patient at another. With the PCR assay, empiric therapy decreased from 29.1% to 10.9%.
Take Home Pearls: Same-day diagnosis of C. difficile using PCR technology appears to allow for the effective use of resources for isolation. It also decreased use of unnecessary therapies and prevented transmission of C. difficile.
Antibiotic Prescription Trends [back to top]
The Particulars: Excessive antibiotic use can lead to the growth and spread of antibiotic-resistant bacteria. Monitoring antibiotic prescribing trends is important to determining if antibiotic use is appropriately being administered.
Data Breakdown: An investigation conducted between 2002 and 2009 revealed that young adults had the same number of or more prescriptions for each antibiotic type studied for urinary tract infections (UTIs), acute respiratory tract infections (RTIs), and skin and soft tissue infections when compared with older adults, with the exception of quinolone prescriptions during visits to EDs for acute RTIs (older adults received more). Younger adults were more likely to receive an antibiotic for UTIs, acute RTIs, and skin and soft tissue infections.
Take Home Pearls: There appear to be differences in antibiotic prescribing patterns between younger and older adults. Patients should be encouraged to take antibiotics exactly as prescribed and discard leftover medications once prescriptions are complete.
Maggots Heal Difficult Wounds in Diabetics [back to top]
The Particulars: Underlying comorbidities of diabetes make wound healing difficult in affected patients. Such wounds can become infected with antibiotic-resistant organisms, which are associated with high management costs. Medical grade maggot debridement therapy (MDT) is an experimental therapy designed to fight infection and accelerate healing.
Data Breakdown: In a study, medical grade MDT was successfully used to treat 21 of 27 patients with diabetes who had failed multiple treatment attempts for complicated wounds over several months to 5 years. Medical grade maggots were purchased for $100 for two treatments.
Take Home Pearl: For the treatment of complex diabetic wounds, MDT appears to be an effective, low-cost, salvage option.
Hospital Privacy Curtains Frequently Contaminated [back to top]
The Particulars: Previous research has shown that hospitals are a significant source of bacteria that can cause serious healthcare-associated infections. Little is known about the effect of potentially harmful bacteria when it presents on hospital privacy curtains.
Data Breakdown: In an analysis of 13 freshly washed privacy curtains hung to separate patientcare areas in the hospital, 12 (92%) were contaminated within 1 week by a potentially harmful bacteria. On at least one occasion, 95% of all curtains demonstrated contamination. MRSA and vancomycin-resistant enterococcus (VRE) were isolated from 21% and 42% of curtains, respectively. At more than one time point, eight curtains were contaminated with VRE.
Take Home Pearls: There appears to be a need for interventions to prevent bacterial contamination of hospital privacy curtains. Hospital staff should wash their hands after touching privacy curtains and before touching patients.
Readings & Resources (click to view)
For more information on these studies and others that were presented at the 2011 Interscience Conference on Antimicrobial Agents and Chemotherapy, go to www.icaac.org.