January 13th, 2018

Just Wondering: Antibiotics for Cough, PJP vs. PCP, TB-Sniffing Rats, Raw Water, and Other Quick ID Items to Ponder

Source: Work Projects Administration Poster Collection [Public domain], via Wikimedia Commons

Here are some “quick questions” with an ID theme for people to consider as we head into week 3 of 52 of this new year.

Just think, by the end of next week, we’ll be nearly 6% done with the new year. How time flies!

For the various items below, if people know the answers, or want to speculate, have at it in the comments section.

  • For patients with a nagging cough, what is the median time before they receive an antibiotic? I’m referring to actual clinical practice, also known as “the real world.” And break it down between adults and kids, please.
  • And for these same treated patients, what percentage receive azithromycin? One estimate has it as 99.9621%.
  • Since vancomycin plus piperacillin-tazobactam increases the risk of acute kidney injury, does this mean less empiric “Vancosyn” in acute care hospitals? Anecdotally, I think it’s having an effect at our hospital — time will tell.
  • When will PJP replace PCP as the preferred abbreviation for Pneumocystis jirovecii pneumonia? More and more residents and fellows seem to be using the former, so that day will come soon. Sorry old-timers!
  • In low TB prevalence regions, what percentage of patients admitted to the hospital with a low clinical suspicion of TB but who undergo a TB rule out “just in case” actually have TB? One estimate has it at 0.0379% (the inverse of the azithromycin estimate above … shocking coincidence). Only our careful Infection Control colleagues can say if this is worth it.
  • When will improved approaches to Lyme testing be available in the clinic? Whether it’s serologic tests, or metabolic changes, or (even better), a reliable PCR or antigen test, here’s hoping this happens soon. Spoiler alert if you haven’t listened to this podcast — and what are you waiting for? — but this is my least favorite test.
  • Will the new zoster vaccine be more broadly adopted than our current one? It’s more effective, more cost-effective, and will be easier to store and distribute, but vaccine acceptance is a tricky business. Factors will include ACIP guidelines, cost and insurance coverage, post-approval safety, and marketing — both to clinicians and direct to patients. Speaking of zoster…
  • Why do so many patients think you can “catch” a case of shingles from someone else? Not referring to primary acquisition of VZV in a non-immune person — that of course can happen. I mean someone getting shingles (zoster) shortly after seeing another person with shingles. Patients continue to think this even after the whole difference between chicken pox and shingles is explained.
  • Did anti-vaccine stupidity reach a new high with this recent Australian case? The father, who had measles as a child, stated he passed on his “natural immunity” to the disease to his children, so they didn’t need the vaccine. Yikes. (H/T to Keith Law for the link.)
  • What proportion of ID doctors just say “isavuconazole” rather than the full name, “isavuconazonium”? This critical (and I mean critical) issue came up right after it’s approval, but now that it’s been out for a while, I’m thinking nearly all of us say the shorter “isavuconazole” — which isn’t so easy to say itself.
  • Why can’t there be a single meningitis vaccine that includes all five serotypes? No doubt there is some immunologic reason, right? Or is it part of the great conspiracy to make meningococcal immunization guidelines as confusing as possible?
  • Does oseltamivir actually work? Depends who you ask. Efficacy debates notwithstanding, we sure use a whole lot of it.
  • Is there any medical reason to use the TDF versions of the elvitegravir- and rilpivirine-containing single tablet treatments for HIV? I can’t think of one; always surprises me when encountering someone who hasn’t switched.
  • What’s the correct dose of daptomycin? Now for the quick answer:  Nobody knows!
  • Has the price of any other other oral antibiotic ever dropped as fast, and by as much, as linezolid? A year ago, two weeks of linezolid cost $3600; today it’s $150. Wow.
  • How many people need to respond to a piece of academic spam — a bogus meeting invitation, or a predatory journal request for submissions — for these emails to become profitable for the senders? There has to be a number, or else this annoying stuff wouldn’t proliferate so wildly.

  • What’s the best way to explain to patients the difference between “TARGET NOT DETECTED” and “VIRAL RNA DETECTED BUT BELOW THE QUANTIFIABLE RANGE OF THE ASSAY”? There has to be a better way than using these words — especially since the clinical relevance is definitely below the quantifiable range of this clinician.
  • Does anyone really understand why ampicillin and ceftriaxone are synergistic against enterococci when given together? The standard explanation is a combination of complete and partial inhibition of various penicillin binding proteins. Confess I still don’t quite get it, since the organism is intrinsically resistant to ceftriaxone, but maybe that’s just me.
  • What explains the media fascination with the giant rats that can diagnose TB? Sure it’s interesting the first few times, but it seems we’re treated to a piece on these clever critters on a regular basis. The Guardian is particularly impressed — “Slow news day? I know, let’s run another piece on the TB-sniffing rats.”
  • How long before we see a serious infection linked to “raw” water? As with the anti-vaccine movement, this pseudo-scientific effort to replace tap or standard bottled water with “off-the-grid” H2O includes a potent mix of homeopathy, paranoia, marketing, and charismatic zealots, with no political persuasion spared. Buyer beware!

Since we finished with a bit of homeopathy, here are three enjoyable debunking pieces — How to Counter the Circus of Pseudoscience and Top Ten Signs Your Detox May Be a Scam. and (coinciding marvellously with the football playoffs), Tom Brady is Trying to Kill You.

Of course these pieces typically preach to the choir, but they sure are gratifying to read.

And our fungal friend Candida makes a predictable appearance early in the second one!

22 Responses to “Just Wondering: Antibiotics for Cough, PJP vs. PCP, TB-Sniffing Rats, Raw Water, and Other Quick ID Items to Ponder”

  1. Robert O. Cannon, MD, MPH says:

    From extensive review of Twitter posts:
    Cough: adult-depends, kids-depends
    Azithro-depends
    VPT-maybe
    PJP-depends
    Tb-depends
    Lyme-depends
    Zoster-depends
    Zoster dos-depends
    Stupidity-depends
    Isa…-depends
    5 serotypes-maybe
    Ose…-depends
    TDF-depends
    Dap…-depends
    Lin…-maybe
    Spam-depends
    RNA-depends
    Enterococci-maybe
    Rats-depends
    Raw H2O-depends

  2. Loretta S says:

    What we really need is a rat that can sniff out the difference between a viral cause of cough/cold/congestion and a bacterial cause. AND can present the results of the sniff to patients in a way that makes them stop asking for an inappropriate antibiotic! Like, oh, let me see… azithromycin.

  3. Stuart Ray says:

    Regarding “Why do so many patients think you can “catch” a case of shingles from someone else?”

    Perhaps we in health care feed this beast? When someone has shingles in hospital, particularly disseminated zoster, we suit up as if it’s a filovirus. It’s not that hard to know whether you’re immune to (infected with) VZV (most of us) in which case it’s impossible to be infected with, and essentially impossible to transmit to others (with basic hand hygeine). So – if we’re irrational in the hospital, why would we expect folks to be rational at home?

  4. Stuart Ray says:

    Regarding ‘What proportion of ID doctors just say “isavuconazole” rather than the full name, “isavuconazonium”?’

    The challenge is illustrated by this related question: are you asking about when we talk about what’s being administered, or what the organism might be susceptible to? While it’s true that the name of the (pro)drug administered is isavuconazonium sulfate, the drug acting on the organism is isavuconazole.

    Perhaps pedantry won’t work here? Communication, after all, is our goal – and in this case, isavuconazole seems perfectly suitable.

  5. Doug Ward says:

    Cough; Anywhere from a week to two months; treatment depends what I think is causing it. Bronchitis (antibiotics). post-infectious inflammation (an inhaler), GERD (PPI), or sinus infection with drainage (antibiotics). For sinusitis I don’t uses azithro…good antibiotic but doesn’t get into sinus tissue well

    Ultimate old time here: it will always be PCP. The Nomenclature Nazis got it wrong on this one. When they decided that there were two Pneumocytes (my Latin training coming through here) they should have assigned “carinii” to the one that causes AIDS pneumonia

    I’m with you on the Lyme testing, but how about its cousin syphilis. Why can’t we get an actual test (like a PCR) for this infection rather than indirect assays like RPRs and FTA

    Absolutely on the Shingles vaccine. In an unpublished (I’m lazy) review of my HIV positive patients the OLD vaccine showed a 99% reduction in cases of shingles. Who would not want this?? And the new one is better, and doesn’t have the silly recommendation of not giving it to HIV positives. All I need is insurance coverage!

    NO reason to use the TDF version of the combination antiretrovirals. Unfortunately, United Health Care doesn’t seem to agree on Descovy.

  6. Joel Gallant says:

    If we allow PCP to be replaced by PJP, it’s our own damn fault. We should correct the youngsters—and teach them some history—every time it escapes their lips. We can also refer them to the original paper in which the organism was renamed but the abbreviation was not.

    • Joel Gallant says:

      I should have cited the paper: Stringer JR, Beard CB, Miller RF, Wakefield AE. A new name (Pneumocystis jiroveci) for pneumocystis from humans. Emerg Infect Dis 2002;8:891-6.

      Quoting from the abstract: “Changing the organism’s name does not
      preclude the use of the acronym PCP because it can be read “PneumoCystis Pneumonia.”

      I also learned from this paper that the species name is pronounced “yee row vet zee,” not “jai row ve see” or “jai row vet cee ai.”

  7. David Kaufman says:

    I’m concerned about the high incidence of side effects reported in The Medical Letter for Shingrix. 17% of recipients experienced severe local reactions ‘preventing normal daily activities’ for a mean of 2 days. This seems an awful price to pay. Maybe we should just give the vaccine on Fridays to ruin a few weekends but no workdays?

    • Paul Sax says:

      David,

      I completely agree that safety and tolerability will be critically important to monitor once the drug is in widespread use. Often “real world” (sorry for that overused term) experiences do not match clinical trials.

      Paul

  8. MN MD says:

    Perhaps a woman planning pregnancy and on TDF/FTC/RPV should hold off on the switch to TAF formulation given the limited data on TAF in pregnancy.

  9. Laura Novak says:

    Re: catching shingles. I really am a scientist, but anecdotally I have had many (> 0.0379%) patients tell me they got shingles after a grandchild visited with chicken pox (I am old). I had 4 bridge partners get shingles within a week of each other after one’s grandchild visited. So that is why the myth persists. One grandchild trumps reams of science.

  10. Max Voysey says:

    I know a rat that could sniff out the difference between a cold and the need for Azithromycin with 100% accuracy – an Azithromycin Drug Rep. (am I allowed to say this naughty thought?).

  11. Pharmacy Student says:

    On my pharmacy rotations, I have noticed that HIV specialists have largely referred to PCP as PCP, and on my current Transplant rotation, I have noticed most of the transplant nephrologists and pharmacists refer to it as PJP.

    In the pharmacies that I have worked in, we have essentially stopped carrying Zostavax and only carry Shingrix now.

    In the specialty pharmacy where I intern, we still see a decent amount of the TDF containing medications prescribed, with occasional switches from a TAF regimen back to a TDF regimen that the patient was previously stable on – we don’t receive explanations, but it has happened a lot more than once.

    In regards to those awful spam journals: https://xkcd.com/870/

  12. Candace Walkley says:

    From Real World Practice Inc:

    Adults: depends on what kind of a mood I’m in, how many times they’ve been in for same complaint, whether they’re the “kind” of personality that I think can be made happy with some perles (or codeine for that matter), how likely they are to come back again if they don’t get abx today, and whether I can finagle any history out of them of purulent nasal discharge that I can intellectually reckon as sinusitis.
    Which Rx they get is based on answers to all above questions. I find more patients just want a work excuse than actually want abx. I always consider it a win when I can ascertain they just want off work.

    Re: Kids
    More than 10 days of cough. This comes from Nelson’s textbook. Surprised me.

  13. ohide says:

    Does the ampicillin & ceftriaxone synergy apply to Benpen and Ceftriaxone?

  14. Henry says:

    Is the OFID podcast listed on the Podcast Addict app/platform? I had tried searching for it on there before and had no luck finding it. Is there any way you can get it listed there?

  15. Dimi says:

    face! soon there’s going to be a facial recognition of bacterial vs viral infection (think of a smartphone app?) http://rspb.royalsocietypublishing.org/content/285/1870/20172430
    dim

  16. Heather says:

    re. catching shingles
    Anecdotally we all know of cases where this seems to have happened. So what’s the evidence that exposure to small doses of the virus can’t be one of the possible triggers for virus reactivation?

  17. DrManzoor says:

    Overuse of antibiotics may cause resistance which is very dangerous for the upcoming generations according to WHO we should develop more new antibiotic as the old one will not work anymore.. Anyhow it is Very well and balance article

HIV Information: Author Paul Sax, M.D.

Paul E. Sax, MD

Contributing Editor

NEJM Journal Watch
Infectious Diseases

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