What Tests Exactly Should My Doctor Order for the 24-Hour Urine Collection?

What tests EXACTLY should my doctor order for the 24-hour urine collection?

This is a common question for stone formers and, frankly, many doctors are unsure of what exactly to look for—below I list the values most typically ordered. 

Remember to read this article to understand the importance of getting a urine collection ordered.

Yes, I do like Litholink for testing. I worked there for many years; this was Dr. Coe’s lab. He sold it to LabCorp, and we make no nickles from talking about it. Litholink’s reporting process is remarkable, which is why LabCorp bought them. BUT. Your doctor doesn’t have to use Litholink. Many doctors are contracted with a specific lab and have no choice in where they order their 24-hour urine collections. Just get the darn thing ordered, no matter where it comes from.


Here is what should ideally be tested for in the 24-hour urine collection (found from Litholink).

• Volume
• Calcium
• Creatinine
• Citrate
• Phosphorus
• pH
• Sodium
• Urea Nitrogen
• Oxalate
• Chloride
• Ammonium
• Magnesium
• Potassium
• Uric Acid
• Sulfate
• Qualitative Cystine screen
• Urine Time Collection
• Supersaturation calculations.

Here are the tests typically ordered for the fasting blood draw that the doctor SHOULD order with your 24-hour urine collection, but often does not.

• Potassium
• Chloride
• C02
• Creatinine
• Calcium
• Phosphorus
• Magnesium
• Uric Acid

If your doctor doesn’t order the fasting blood draw, don’t let that hinder you from getting the urine collection ordered—that is the most important thing. You can always get the blood test later. I am alerting you to the Gold Standard of testing, but not all labs will report on precisely these values. It should be pretty darn close, though. 

Please, I beg you, please tell your doctor to order a 24-hour urine collection if you have kidney stones. These tests can reveal the causes of your stones and they are often things you’d never expect.

If you already have your test results and want to better understand them so you can have more productive doctor visits, schedule a urine consult. You’ll be glad you did. Promise.

Thanks for being here with me. Your trust is never taken for granted.

Your friend and advocate,
Jill