Thread by @ebtapper

Why is your pt's ALT (or AST) >1000?
A #livertwitter #tweetorial

Take-homes:
1. Top 3 causes of acute liver injury
2. I always say it's ischemic hepatitis; 50% of the time, I'm right every time

Brought to u by:
@tonybreu et al. What causes severe ALI?
cghjournal.org/article/S1542-…

The liver is awesome.

Yet its vocabulary is ... limited.

We can all tell when it is upset - high ALT, AST.

But that could mean anything!

So what's your specific patient's specific reason for high ALT?

First - a poll:
What's the most common cause of severe acute liver injury
(ALT or AST > 10xULN)?

Chances are, in your hospital, a sky-high ALT earns six pints worth of serologic tests

A few months ago, I saw someone check Parvo

Parvo is the new EBV

But ... what ACTUALLY causes severe acute liver injury?

Check out this multicenter study (community/transplant/VA) led by THE @tony_breu - hot off the presses

Top 3:
- Ischemic hepatitis
- Stones / biliary causes
- Drugs

ref: cghjournal.org/article/S1542-…

Notice...blood tests may not find the top 3

There are 4 types of blood tests for ALI:

1: HAV/HBV/HCVtylenol
2: Things that never-ever cause ALI (Fig1)
3: Things that are occ. helpful and often misleading (Fig2)
4: Things the AGA recommends NOT testing (ceruloplasmin, Fig 3)

Knowing the true DDx tells us what 2 do

1. Drugs: Start NAC if tylenol! If not, NAC still ok (Fig1)
2. Acute CBD stones happen! (Fig2). Ultrasound vs MRCP --> ERCP.
3. Ischemic hepatitis... see act 2

Summary (Fig 3): Stepwise testing for severe ALI
journalofhospitalmedicine.com/jhospmed/artic…

Act 2:

Who gets ischemic hepatitis?

1. It's not just about hypotension!(Fig1) If it was, every patient in the ICU would have ALI.
2. 90-100% of patients w/ischemic hepatitis have CHF, almost always right heart failure (Fig1-2)
3. Indeed, 🔼ALT is a risk biomarker in CHF (Fig3)

The mechanism of ischemic hepatitis:
1. Liver has dual blood supply. 75% portal vein(5mmHg), 25% hepatic artery(Fig1)
2. CHF▶️congestion▶️venous htn >portal pressure🔽o2 diffusion in sinusoid
3. Liver arterializes▶️dependent on hep art(Fig2)
4. Transient🔽BP▶️🔥(Fig3)

Why tweet about this?

1. Ischemic hepatitis is common and deadly.(Fig1) Often unrecognized.
2. I suspect right CHF is under-recognized. Correct me if wrong
3. While you are checking liver labs, please think about ischemic hepatitis and right HF.

ref: sciencedirect.com/science/articl…

This concludes a #livertwitter #tweetorial on ischemic hepatitis. I hope you enjoyed it. Thanks as always to @tony_breu for his #meded-inspiration