2/ First, I want to emphasize that this project highlights many of the reasons I chose to pursue a #PhD in clinical & translational science. As a long-time microbiologist, I can say that the clinical lab doesn't often have a seat at the clinical effectiveness / research table.
3/ This project focuses on the tracheal aspirate culture- a diagnostic process that is greatly limited by contamination with normal respiratory flora, and which lacks consensus or standardization across labs and hospitals. @ASCLS @ASMicrobiology @ASCP_Chicago
4 / When combing through the literature, you will often find that ventilator-associated pneumonia ( #VAP)(and/or tracheitis) studies rely on different laboratory methods for TAs, which makes the findings hard to interpret or apply across centers.
5/ Additionally, studies seem to make assumptions about what the lab is doing with TAs, or even go so far as to have a clinician perform testing elements such as reading Gram stains (instead of the lab). Most importantly: the lab is never really asked about their process.
6/ We wanted to dive deeper in to the TA culture process on the laboratory side. TA cultures serve as a major stewardship problem that needs to be addressed on both the clinical & lab side. If we are going to improve the process, we HAVE TO TALK TO THE LAB!
#ASMClinMicro @ASCLS
7/ We used the PHIS database to identify pediatric hospitals and assess for eligibility. We excluded any labs that did not perform microbiology in-house, or for which there was no contact information. This = 107 Adult+peds & 46 freestanding peds hospitals.
8/ An important thing to understand about labs: Not all #labs have a PhD-level director, and even if they do, that person may not be the person who can speak to the intricacies of the bench-level procedure for tracheal aspirate cultures.
9 / I personally reached out to every lab to ask for participation and ensure that we were surveying the most appropriate people. I loved this part. Microbiologists are wonderful.
@ASMicrobiology #ASMClinMicro
10 / The overall response rate was 48% (73/153), including a response rate of 69% (32/46) for freestanding pediatric hospitals. Considering this was a digital survey of (mostly) total strangers, this is great!
11 / We found a lot of interesting things from this survey, but here are the key findings:
1. There is a lot of variability across hospitals when it comes to the tracheal aspirate culture process. This is true from start to finish
12 / Only 7% of labs reported being aware of if a TA specimen has been diluted with saline when it arrives in the lab. We know that saline is frequently used during suctioning, but the lab is rarely made aware of this. This affects the results and the way things are reported.
13 / 44% of labs have rejection criteria based on how long it takes the sample to reach the lab, but those criteria varied quite a bit.

23% of labs reject TA specimens based on Gram stain criteria, but there wasn't a whole lot of agreement on the method for this either.
14 / There is a lot of variability in other Gram staining components such as which objective to use to quantify human cells - the majority use the 10x objective, but 10% use 40x and 23% use 100x.

56% of labs use minimum field review criteria, but these ranged from 5-100 fields
13/ In the culture domain of the survey, we asked about ID & reporting practices for organisms that are potential pneumonia pathogens. For each, we wanted to know: if they are ALWAYS reported (no matter what), or when other factors like predominance or Gram stain come into play.
14 / Bottom line: this varies quite a bit between labs.
Overall, nonacademic labs are more likely to always ID and report S. pneumoniae, S. aureus, P. aeruginosa, enteric GNRs and nonfermenting GNRs regardless of factors like purity, predominance, original Gram stain (P<0.05).
15 / Freestanding pediatric labs are more likely to always identify and report Group A strep and P. aeruginosa, regardless of other factors like purity, predominance in culture, or original Gram stain results (P<0.05).
16 / Important themes that emerged from the free-response section include:
1. Microbiologists find the existing process to be frustrating, challenging, and in need of formal guidance.

2. Pressure from clinicians to report certain organisms is a big issue (and drives processes)
17 / Concluding thoughts:
1. We use TA cultures in pediatrics a lot. They are less-invasive, and when collected appropriately and interpreted well, can be very helpful for the diagnosis of pneumonia or tracheitis...which are very serious conditions. BUT...
18/
2. The lack of standardization on both the clinical and laboratory side render them unhelpful (and often confusing).
3. It is really hard to determine what is a colonizing organism and what is a respiratory pathogen in each patient.
19/
4. We are all doing different things. This makes interpretation, quality improvement, and communication around these cultures challenging.

5. Without data to support the microbiology lab, it is hard to implement changes to the process due to clinician preferences.
20/ So, what to do next?
✔️Demonstrate that weeding out the contaminated, poorly collected, unhelpful TA cultures =better patient care.
✔️Use these data to help support labs make appropriate changes to their process.
✔️No more siloed diagnostics work! Involve all parties.
21/Optimize and utilize dissemination and implementation science techniques to better understand the context around this diagnostic tool. Involve EVERYONE -- pulmonary, microbiology, infectious diseases, critical care, etc. Implement something that is sustainable.
#TeamScience
23/ Finally, I am so thankful to all of the microbiologists who took the time to share their process and opinion(s). The #IDTwitter world functions well because of your added expertise. You play an enormous role in #diagnostic and antimicrobial #stewardship. Also, I love you.
You can follow @andreaprinzi.
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