Overlap is common because these abnormalities commonly occur together.
3.
Every week I will add my thoughts to this #pathtweetorial . I feel strongly about this topic because I see SO much smoking-related lung pathology that is misinterpreted and underrecognized. Not just SRIF (👇🏾) but also pigmented macrophages, commonly dismissed as “anthracotic”
4.
Let us start with pigmented macrophages. These are extremely common in the airspaces (alveolar lumens) of current and ex-smokers. Known since 1974 when Niewohner et al described them in @NEJM (PMID 4414994) in the lungs of young smokers.
5.
This paper is the origin of the problematic term “respiratory bronchiolitis”. Why problematic? These cells are neither limited to bronchioles nor a true “itis”.
In reality, you will most commonly see these pigmented macrophages within alveoli.
6.
Look at these pics. Are these cells in bronchioles or alveoli?
Such a common smoking-related finding, yet we either use the wrong location (RB) or misrepresent the etiology by implying it’s related to coal (anthracotic). Why? Because we don’t have a better term.
7.
I used to label them as RB but have started calling them what they are: pigmented airspace macrophages.
If I see them in a known smoker and I’m sure the pigment is not hemosiderin, I say: pigmented airspace macrophages, smoking-related
8.
I do not mean to disparage the Niewohner paper by pointing out that respiratory bronchiolitis was not the best term.
The paper is a landmark in our understanding of the histologic changes that smoking causes in the lungs before emphysema develops.
Key cells: macrophages
9. Correction: PMID is 4414996. Interestingly, this highly cited study was done at Case Western Reserve Univ, just a few minutes’ walk from where I am right now.
Others (Pratt 1969, Harris 1970) had previously noticed increased macrophages in BAL specimens from smokers.
10.
The very next year, an electron microscopic study looked at these pigmented macrophages from smokers in breathtaking detail!
The study was by Brody and Craighead, 1975. They called the cytoplasmic particles derived from cigarette smoke “smokers’ inclusions”
PMID: 163418
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1/4 (4-tweet thread)
A recent study in @ModernPathology
by Xie et el examined the ability of a deep convolutional neural network to diagnose which tumor in pleural effusions? #pathpolls
3/4
The authors claim the sensitivity and specificity of the deep convolutional neural network was somewhere between senior and junior cytopathologists. What were the numbers (sensitivity, specificity)?
cc: @DrNetto
1/ Announcing a contest to win a free pathology textbook!
Thanks to a brilliant idea by @DrMissWV and a generous offer by @science_press and @LizMontgomeryMD we are giving away a few free textbooks in an educational tweet contest called #pathbracket . See thread 👇🏾
2/
If you want to enter the contest, create a NEW educational pathology tweet between today and March 15 and tag it with #pathbracket
You must tag your own tweet. The tweet must have educational value. Tweetorials are allowed too. Contest is open to all.
3/ On March 16, #PathTweetAward judges led by @DrGeeONE will donate their time to pick 32 of the best tweets to enter in a bracket similar to #MarchMadness . Credit with the idea of a bracket goes to @DrMissWV
Progression through the bracket will be on the basis of polls.
1. How do we tell primary lung cancer from metastatic cancers from other sites?
It’s correct to say we should use all available clinical, radiologic and pathologic information, but that’s too vague to be helpful in a practical sense.
2. This #pathtweetorial is applicable mainly to #pulmpath . The principles in each organ are different. A carcinoma in a lymph node is a metastasis by definition. Not so in lung or colon.
IMHO it’s a mistake to approach a carcinoma in the lung as carcinoma of unknown primary
3. Most metastatic carcinomas to the lung occur after the primary carcinoma has already been diagnosed in another site.
💥Clinicians: give your pathologists this information! If you don’t, this is substandard, dangerous patient care.
I’m starting a thread on #COVID19 just to keep everything I learn about it in one place.
🌹 New information
🌹 well summarized information
🌹 Things that changed my mind
🌹 Things that I did not expect
2. Great update with Dr. Fauci
Most interesting tidbit: why is well controlled hypertension a risk factor? Could ACE inhibitors be predisposing to coronavirus infection by increasing ACE receptors?
Link to video 👇🏾
3. Podcast episode 3/17 by @nytimes . Very moving interview with a pulmonologist who has treated dozens of patients in Bergamo, Italy. Warning: it will make you cry.
“Nothing is as before”
They see 50-70 patients with severe pneumonia every single day