7-Ketolithocholic Acid Test

Your gut bacteria do more than digest food. They take the bile acids your liver releases and rework them into dozens of secondary compounds, some of which feed back into liver health, blood sugar control, and gut function. 7-KLCA (7-ketolithocholic acid) is one of those microbe-made byproducts, and shifts in its level have shown up in liver disease, diabetic kidney disease, and other conditions where the gut and liver are out of sync.

This is a research-grade marker without standardized clinical cutpoints, so a single number is not a diagnosis. What it offers is a baseline view of your bile acid chemistry that standard liver enzymes and stool panels do not capture, and a starting point for tracking how your gut and liver are responding to changes you make.

What This Bile Acid Actually Is

Your liver makes primary bile acids, mainly chenodeoxycholic acid and cholic acid, to help you digest fat. Once those bile acids reach the colon, gut bacteria carrying enzymes that strip and rearrange chemical groups (such as 7-alpha-hydroxysteroid dehydrogenase) convert them into secondary forms. 7-ketolithocholic acid is one of those secondary forms, sitting on the pathway between chenodeoxycholic acid and ursodeoxycholic acid, the same bile acid used as a medication for liver disease.

Because it is microbe-made, the level of 7-KLCA in your stool reflects two things at once: how much bile your liver is sending into the gut, and which bacteria are present to process it. That makes it a snapshot of the gut-liver axis, the constant chemical conversation between your liver, your microbes, and your intestinal wall.

Liver Disease and Fibrosis

The clearest signal that 7-KLCA matters comes from fatty liver disease. In a study of 102 adults across the spectrum of NAFLD (non-alcoholic fatty liver disease), plasma 7-ketolithocholic acid was higher in people with NASH (non-alcoholic steatohepatitis), more advanced fibrosis, hepatocyte ballooning, and steatosis. The finding sits inside a broader pattern of elevated 7-keto bile acids tracking with worse liver histology and faster disease progression.

That study measured plasma rather than stool, so the evidence does not directly prove that fecal 7-KLCA tracks fibrosis the same way. Still, since stool levels reflect the same microbial conversion that feeds plasma levels, an unusually high fecal reading in someone with metabolic risk factors is worth taking seriously alongside liver enzyme testing and imaging.

Diabetic Kidney Disease

In a study of 60 adults with type 2 diabetes and biopsy-confirmed kidney disease, fecal 7-ketolithocholic acid was among the bile acids that shifted as kidney function declined. The pattern was step-wise, meaning levels changed across mild, moderate, and more advanced stages, suggesting fecal 7-KLCA tracks the bile acid disturbance that accompanies progressing kidney damage in diabetes rather than just reflecting the diabetes itself.

If you have type 2 diabetes and an elevated 7-KLCA, that result alone is not a kidney diagnosis, but it earns the right to be paired with eGFR (estimated glomerular filtration rate, a measure of kidney filtration) and a urine albumin-to-creatinine ratio so you can see whether the bile acid signal lines up with kidney function changes.

Other Disease Associations

In a study of 432 adults with schizophrenia, serum 7-ketolithocholic acid was lower than in healthy controls as part of a broader reduction in circulating bile acids. The clinical meaning of a low fecal 7-KLCA in mental health is not established, and these data come from blood rather than stool, so they should be read as a hint that bile acid biology connects to brain health rather than as a diagnostic threshold.

In a smaller observational study of children with biliary atresia, lithocholic acid derivatives, including 7-keto species, correlated with the gut bacterium Enterococcus faecium and with markers of ongoing liver injury. This is a specialized pediatric setting and does not translate to adult screening.

Reference Ranges

There are no consensus clinical reference ranges for fecal 7-ketolithocholic acid. Major guideline bodies have not defined cutoffs for normal, borderline, or elevated levels, and population studies have not produced widely accepted percentile distributions. Different labs use slightly different testing methods, and absolute values can shift between assays.

What this means in practice: rather than chasing a fixed target, use your first reading as your personal baseline and compare future tests within the same lab. If your level is unusually high or low compared to the lab's reported range, treat it as a flag to investigate the rest of your bile acid panel and your gut-liver health, not as a standalone diagnosis.

Tracking Your Trend

A single stool measurement of any bile acid is a snapshot of a system that changes daily with diet, sleep, and microbial composition. The trend matters more than the number. If your first result is elevated, retest in 3 to 6 months after making meaningful changes (fiber, probiotic strategy, treating underlying liver or metabolic conditions) so you can see whether the trajectory is moving in the right direction.

For ongoing monitoring, an annual recheck is reasonable for proactive adults, with shorter intervals if you are actively managing a metabolic or liver condition. Always retest in the same lab to keep results comparable.

When Results Can Be Misleading

• Recent antibiotics: wiping out part of your microbiome can collapse secondary bile acid production within days. A reading taken during or shortly after a course of antibiotics may not reflect your usual bile acid chemistry. Wait at least 4 to 6 weeks after finishing antibiotics before testing.
• A single high-fat meal or recent fasting: bile acid output rises with meals and falls during fasting. Follow your lab's collection instructions exactly so your sample reflects your usual diet.
• Bile acid sequestrant medications (cholestyramine, colesevelam): these drugs bind bile acids in the gut and shift the entire fecal bile acid profile. Levels can change without any change in the underlying gut-liver biology you are trying to assess.
• Gallbladder removal or recent gut surgery: anatomical changes alter how bile acids cycle through the gut and can shift the relative balance of primary, secondary, and keto species without indicating disease.

What to Do With an Abnormal Result

An abnormal 7-KLCA reading is most useful when read alongside the rest of your bile acid panel and your broader gut and liver picture. If the result is elevated, look at total fecal bile acids, primary versus secondary balance, and other secondary species like deoxycholic and lithocholic acid. Pair the panel with liver enzymes (ALT, AST, GGT), an updated lipid profile, and, if you have metabolic risk factors, fasting insulin and HbA1c.

Patterns that warrant a closer look include high fecal 7-KLCA alongside elevated liver enzymes (a hepatology workup), high 7-KLCA with declining kidney function in someone with diabetes (a nephrology consultation), or a globally distorted bile acid profile suggesting microbial imbalance (a gastroenterologist familiar with bile acid biology). A single elevated reading without other findings is a reason to retest and watch the trend, not to start aggressive treatment.