Thread by @JonathanRyderMD

My 3rd week of general ID @UNMC_ID has come to a close with #PasteurellasFellas, led by the wonderful @KellyCawcuttMD! Really appreciate her critical care insight on ID. We had some fascinating discussions this week. Time for another recap! #IDTwitter #IDPearls

A fundamental question this week was TB or not TB (sorry, not sorry for the pun @bergmanscott)

ncbi.nlm.nih.gov/pmc/articles/P…

We discussed the differential diagnosis of miliary nodules on imaging. TB leads the list, but dimorphic fungi (histo, blasto, cocci) can be just as common in endemic areas. Malignancy as well.

atsjournals.org/doi/pdf/10.151…
ncbi.nlm.nih.gov/pmc/articles/P…

The idea of a "TB rule out" was discussed. You can now use 2 negative GeneXpert MTB/RIF PCRs to remove airborne precautions as this makes INFECTIOUS TB unlikely (does not rule out TB). This is much faster than 3 negative AFB smears (saves PPE too!)

tbcontrollers.org/docs/resources…

We asked, "what role does IGRA play in diagnosis of active TB?" TLDR: not much per this meta-analysis.

For Quant Gold, sensitivity 80%, specificity 79%.

For T-Spot, sensitivity 81%, specificity 59%.

Not high enough to rule in or rule out active TB

erj.ersjournals.com/content/erj/37…

All month we have discussed AmpC & the SPICE (or SPACE) organisms

The concepts of inducible AmpC vs stable derepression (or hyperproducers) has always been confusing to me, but this article helps to clarify with a great graphic

ncbi.nlm.nih.gov/pmc/articles/P…

For these AmpC organisms, I generally use cefepime for treatment. However, this study challenged that for me, showing pip-tazo to have nearly equivalent outcomes (albeit some limitations).

aac.asm.org/content/aac/61…

And while on the gram negatives subject, we had another #ShorterIsBetter conversation when it comes to gram negative BSI. 7 days non-inferior to 14 days. (Note to self: this is NOT the STOP-IT trial, that is for cIAI! My bad team!)

academic.oup.com/cid/article/69…

Let's finish up with the TB of the Midwest: histoplasmosis! So much to learn with this topic, so I'll hit some highlights. First, is the amazing #tweetorial from @TxID_Edu on histoplasma antigen testing!

https://twitter.com/TxID_Edu/status/1186731997424738306

For a great review on the topic, this paper by @FungalDoc & others is succinct & high-yield

id.theclinics.com/article/S0891-…

The histoplasmosis guidelines are over a decade old, but still provide guidance on treatment

To no one's surprise given their geography, I see lots of familiar names from @UNMC_ID & @IUIDfellowship contributing to many key histo papers!

academic.oup.com/cid/article/45…

When it comes to histo treatment, itraconazole is invariably involved. As I learned from @eColeID, itraconazole is best absorbed in an acidic environment. @CocaCola has been shown to increase itraconazole absorption (due its pH of 2.37!) OJ works too

pubmed.ncbi.nlm.nih.gov/9218932/

That's it for this week! One more week left of gen ID with this crew, can't wait! #PasteurellasFellas @MrSmartyPants_1 @ADreessen21 @HannahLuksa @tiff_truong @Molly_M_Miller @amandav_pharmd @UNMCIMResidency