Wednesday, June 29, 2011
While wandering about, I got a cool text message from Preeti Malani, an Associate Editor at ICHE, who informed me that the ICHE journal impact score is up to 3.751 - that's quite a huge jump in 1 year. I suspect it will be even higher next year given the size of the 1-year jump. Independent of how you feel about impact scores, it is still very good news for those of us that publish in this excellent and well-focused journal. Given that promotion and tenure of medical school faculty often depend on publication in high impact journals, this is a big deal for academic types. Three cheers to the entire ICHE editorial board and especially Suzanne Bradley, whose tireless efforts should now be fully appreciated.
...and to emphasize that you can never rest on your laurels...Andreas Voss, the ICPIC co-chair, just announced a new BMC journal titled - Antimicrobial Resistance and Infection Control (ARIC). The website for submissions is not yet active, but I will post the info when it becomes available.
Monday, June 27, 2011
Saturday, June 25, 2011
|Photo: Kirk McCoy, LA Times|
Thursday, June 23, 2011
Wednesday, June 22, 2011
In my last post about the newly described MRSA strains that carry the mecALGA251, I referred again to the “empty cassette variants” (or “mecA dropouts”) that are missed by commercial MRSA PCR tests that target the orfX gene but don’t contain mecA primers. I also mentioned that we’d soon be publishing our first year of experience with this. Well, here is the short report I was talking about, describing our ~8% rate of false positivity due to empty cassette variants, and characterizing the strains in question. We found substantial genetic diversity among the “drop-out” strains, meaning that the problem wasn’t due to the introduction of a single clone. When we tested these MSSA isolates using the newer GeneXpert MRSA/SA Nasal Assay (the “Nasal Complete” assay), they were correctly identified as S. aureus but not MRSA (this new assay has primers for the mecA gene). Even the “Nasal Complete” assay is susceptible to false positives, though, from the simultaneous presence of an MSSA and a methicillin-resistant coagulase-negative staphylococcus (MR-CoNS) in the same nose (the prevalence of MR-CoNS + MSSA co-colonization was 3.4% in one study). Indeed, the package insert describes a PPV of about 75% for the Nasal Complete—for MRSA, the 25% “false positives” divide equally between those for which culture was negative (which might reflect increased sensitivity of PCR) and those for which the culture grew only MSSA (which may reflect MR-CoNS/MSSA co-colonization). Who knew the nares would be such a vexing place for those who design and market PCR tests?
Sunday, June 19, 2011
I just returned from my first HICPAC meeting….and no, I won’t risk being thrown off the committee for discussing all of our deliberations on this blog (at least right now I won’t). However, I did want to point out a fun moment from a presentation by John O’Brien from CMS. John gave an update on the CMS Partnership for Patients, which we blogged about earlier.
The PFP is still nascent, and we’ll see how much of an impact it has on the ground. But the presentations by Joe McCannon at SHEA and this one from John O’Brien were both encouraging, and almost certainly reflect the impact that Don Berwick has had on the culture there. The photo above was taken at the break after John’s lecture. As you can see, there is a painting on the back of his suit jacket, depicting patient safety themes. During his talk he briefly discussed this “walking art”, and how it helps start conversations in airports, at conferences, etc. The painting is the work of Regina Holliday, a Washington DC-based patient rights arts advocate. The full story and explanation of the images on the jacket can be found on her blog, here.
Saturday, June 18, 2011
Wednesday, June 15, 2011
In this video a British surgeon barges into a room where the Prime Minister is talking with a patient and kicks out the cameraman because he's not bare below the elbows. Interestingly. the Prime Minister is bare below the elbows and tieless. You can read about the scandalous surgeon here.
Tuesday, June 14, 2011
Monday, June 13, 2011
Wednesday, June 8, 2011
Idea Title: Driving Patient Safety with Point-of-Use Signs for Hand Washing
Idea Description: One of the biggest threats to patient safety is hospital-acquired infections. Hand hygiene is the #1 method for preventing the spread of infections. VA has done a great job placing alcohol hand rub dispensers in patient care areas, but hand washing isn't 100%. Placing point-of-use reminder signs directly next to hand-rub/soap dispensers to encourage providers to wash their hands has potential to significantly improve hand washing compliance. Signs that offer encouragement and information and not just say employees must wash hands would be simple to design, test, implement and be very cost-effective.
Tuesday, June 7, 2011
Reports of the emergence of novel MRSA strains bearing mecALGA251, discussed in Eli’s excellent post, were published just as I finished a pro-con session at ASM on the use of culture versus PCR for clinical detection of MRSA. I pointed to the ongoing evolution of MRSA as a drawback to existing PCR methods, and included reference to the "empty cassette variants" that I previously discussed.
Because I think the "empty cassette" or "mecA dropout" story is instructive here. When the orfX-based assays were initially released, the published data described a very low incidence of these variants (in the case of the "mecA dropouts", isolates of MSSA that tested positive by the GeneOhm-GeneXpert-BD test...the opposite problem we see with the mecALGA251 isolates, which are MRSA that test negative....). So the potential problem was minimized, mainly for lack of good data and an assumption that clinical labs wouldn't run across these strains very often. Of course, some labs (including ours) did run across them quite often (“empty cassette variants” constitute almost 8% of our positive tests, a finding we'll soon publish (manuscript "in press" at JCM)).
Similarly, we are going to hear about how rare these mecALGA251 isolates are, how clinical labs are not likely to run across them, the tests still perform well, etc., etc. But how will we know when we start running across them? Of the hundreds of labs doing MRSA nares screening by PCR, how many are doing culture in parallel (not just on positives, but on negatives as well)? Of the labs that do only culture, how many are also doing confirmatory mecA PCR and following up on any phenotypic MRSA that test PCR negative?
More to come on this topic, and what is says about the future of PCR testing for MDRO detection, in future posts...
The report out of Ireland discusses two clinical MRSA isolates that were PBP2a-positive but mecA negative by conventional mecA PCR - ie they were called MSSA by GeneXpert. The first strain was isolated from a 64-year old in a Dublin acute care hospital, while the second was isolated from an 85 year-old in a South-East Ireland regional hospital. Evaluation determined that these strains contained a novel SCCmec element (Similar to SCCmec XI) with divergent mecA, mecI, mecRI, blaZ and ccr genes.
In the second report, investigators out of England noticed bovine MRSA strains which tested negative after standard PCR tests for mecA. They determined that they contained a novel mecA homologue, mecALGA251. They then searched collections in Scotland, England and Denmark for similar strains and 51 human isolates with the same mecALGA251. 14 of 25 from London, 12 of 16 from Glasgow and 24 of 32 clinical strains from Copenhagen contained the novel mecA. One human strain dated back to 1975, although detection increased substantially between 2007 and 2010. 54% (13/24) of the bovine isolates were also positive. The distribution of cattle and human isolates in England is shown above.
The authors of this paper suggest that new PCR primers will solve the problem. It is true that it will solve this particular problem, but is it a good long term solution? Do we think MRSA evolution will stop here? Also, they suggest that dairy cows could be a reservoir of infection, but I would think that humans could also be the reservoir.
What this suggests to me is that if you isolate/decolonize patients using a static PCR for mecA, it is not surprising to me that other novel strains could emerge. Hand hygiene would not be so easily circumvented, nor would simpler culture-based microbiology methods.
Hopefully our resident microbiologist Dan will chime in too...
UK and Denmark report: Garcia-Alvarez et al. Lancet ID June 3, 2011
Ireland report: Shore AC et al. AAC, June 2, 2011
Tara Smith's take can be found here and Scientific American's report by Katherine Harmon here
Monday, June 6, 2011
On a more positive note, the Connecticut legislature has passed a bill that mandates sick pay, which should help to reduce presenteeism, though lack of sick pay was likely not the problem at the Chicago hospital. Nonetheless, I don't think that most hospitals are making a sincere effort to keep sick workers at home.
Sunday, June 5, 2011
Some new developments today in the enormous enterohemorrhagic E. coli (EHEC) outbreak in Germany, an outbreak that has sickened at least 1600, caused over 600 cases of hemolytic uremic syndrome (HUS), and killed 22 so far. Daily updates can be found at the European CDC site, here.
Eli has blogged several times about the FDA Food Safety Modernization Act, which was passed several months ago. That law will do little to protect U.S. consumers from foodborne illness, however, if the FDA is not provided sufficient funding to implement it. Perhaps they should serve a delicious bean sprout salad at the next House Appropriations subcommittee meeting--we'll find out if our representatives are confident enough in U.S. food safety systems to eat it.
Thursday, June 2, 2011
There’s an interesting (but very small) pilot study in the British Journal of Surgery that examines the relationship between operating room noise and surgical site infection (SSI) rates. A Swiss group--which previously correlated a subjective perception of increased noise with SSI--measured sound levels in 35 ORs during elective abdominal operations. Median sound levels were significantly higher during cases of patients who subsequently developed SSI (43.5 dB vs. 25.0 dB, p=0.04). Also of note: talking about non-surgery-related topics was associated with higher sound levels, and sound levels increased about 60 minutes after incision. Since we already know that SSI risk increases with the duration of a procedure, it may be that longer surgeries are also associated with more, and louder, non-surgical conversations as the team becomes bored or distracted (though not statistically significant, the procedure duration was longer for SSI patients in this study (mean of 390 vs. 255 minutes)). And as the authors note, higher sound levels could simply reflect the difficulty of a procedure (suction machines, alarms, louder and longer conversations, primal screams, etc.). Future studies could help determine if higher OR sound levels are just markers for difficult, stressful cases, or if more noise negatively affects surgeon performance (or both!).
|Photo: New York Times|
Wednesday, June 1, 2011
|Photo: Jeff Swensen, New York Times|
Tekerekoglu, et al. AJIC June 2011