Mildly Elevated LFTs: A Primary Care Guide | Hippo Education

It starts the same way almost every time. You’re clicking through routine labs — A1c, lipids, CBC — all normal. Then you pause. AST 52. ALT 68. The patient feels fine. The visit was for knee pain. And now you’re left holding a lab abnormality that’s just… sitting there. Not high enough to panic. Not normal enough to ignore. So what do you do next? About 1–4% of asymptomatic patients have abnormal liver enzymes, and most of us see this every week in clinic.

First, Zoom Out: What Are We Really Looking At?

AST and ALT are markers of hepatocellular injury, but they’re not specific to the liver alone. Muscle, for example, can contribute, and importantly, “mild elevation” usually means less than 5 times the upper limit of normal. In primary care, the most common causes include:

• Metabolic-Associated Steatotic Liver Disease (MASLD)
• Alcohol use
• Medications or supplements
  
  

Step 1: The History You Almost Rushed Past

This is where most of the diagnosis lives.

A few high-yield questions can save you a cascade of unnecessary and expensive testing:

• Medications & supplements: NSAIDs, statins, antibiotics, herbals, gym supplements
• Alcohol use: Not just yes/no — quantity and pattern matter
• Metabolic risk: Diabetes, obesity, hypertension
• Viral risk factors: Travel, sexual history, tattoos, prior transfusions
• Family history: Hemochromatosis, liver disease

And don’t forget the subtle stuff such as new protein powders, “liver cleanse” teas (my favorite) and intense exercise.

Step 2: Don’t Overreact, Repeat First!

If the patient is asymptomatic and labs are only mildly elevated, it’s reasonable to:

Repeat LFTs in 2–3 months before launching a full workup.

Why? Transient elevations happen. Illness, exercise, and medications can all nudge enzymes up temporarily.

Step 3: When It Persists, Start a Focused Workup

A solid first-pass workup includes:

• Hepatitis B and C serologies
• Iron studies (Iron Panel, Ferritin)
• CBC
• Abdominal ultrasound

At this point, most patients fall into three buckets:

1. Looks Like MASLD

Clues:

• Metabolic risk factors
• ALT > AST (ratio <1)
• Ultrasound shows steatosis

What next?

• Lifestyle modifications
• Consider fibrosis risk stratification (e.g., NAFLD fibrosis score)
• Use ultrasound to assess liver structure

Then risk-stratify:

• Low risk → Continue lifestyle modification
• Higher risk → Intensify changes and consider GI referral

2. Workup Is Negative

You’ve ruled out the big stuff. The patient feels fine. Labs are still mildly abnormal.

Now what?

• Observe
• Consider extrahepatic causes

Commonly missed contributors:

• Thyroid disease (check TSH)
• Celiac disease (check TTG, total IgA)
• Muscle injury (check CK if relevant)

If everything stays stable and mildly elevated, watchful waiting is reasonable.

3. Something Comes Back Positive

If your labs point to a specific diagnosis — viral hepatitis, iron overload, autoimmune disease — follow that thread.

And this is where you may consider a GI referral.

Clinical Pearls You’ll Actually Use

• AST: ALT ratio matters
• 2 → think alcohol-related liver disease
• <1 → think MASLD
• Alkaline phosphatase isn’t always liver
• Check GGT to confirm hepatic source
• Normal synthetic labs (Albumin, PT/INR) don’t rule out early disease
• MASLD is everywhere — and increasing

The Part We Don’t Always Say Out Loud

These cases can feel deceptively low-stakes. The patient feels fine. The numbers are only a little off. It’s easy to push it down the problem list. But here’s the tension:

• MASLD is becoming a leading cause of liver transplant
• Cirrhosis remains a major cause of morbidity and mortality
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So What Should You Actually Do Tomorrow?

When you see that slightly elevated AST/ALT:

1. Pause but don’t panic
2. Ask more detailed history questions
3. Repeat before reacting
4. Run a focused, not exhaustive, initial workup
5. Lean into lifestyle counseling
6. Refer when the story stops making sense

Not every abnormal lab is a crisis. But some are invitations to look a little closer, take a more detailed history, and catch something early enough to matter. Mildly elevated LFTs live in that space, and when handled well, they’re one of those everyday primary care moments where we really do change a patient’s trajectory.