Cortisol is a steroid hormone synthesized from cholesterol by a multienzyme cascade in the adrenal glands. It is the main glucocorticoid in humans and acts as a gene transcription factor influencing a multitude of cellular responses in virtually all tissues. Cortisol plays a critical role in glucose metabolism, maintenance of vascular tone, immune response regulation, and in the body's response to stress. Its production is under hypothalamic-pituitary feedback control.
Only a small percentage of circulating cortisol is biologically active (free), with the majority of cortisol inactive (protein bound). As plasma cortisol values increase, free cortisol (ie, unconjugated cortisol or hydrocortisone) increases and is filtered through the glomerulus. Urinary free cortisol (UFC) in the urine correlates well with the concentration of plasma free cortisol. UFC represents excretion of the circulating, biologically active, free cortisol that is responsible for the signs and symptoms of hypercortisolism.
UFC is a sensitive test for the various types of adrenocortical dysfunction, particularly hypercortisolism (Cushing syndrome). A measurement of 24-hour UFC excretion, by liquid chromatography-tandem mass spectrometry (LC-MS/MS), is the preferred screening test for Cushing syndrome. LC-MS/MS methodology eliminates analytical interferences including carbamazepine (Tegretol) and synthetic corticosteroids, which can affect immunoassay-based cortisol results.
------------------
Values in the normal range may occur in patients with mild Cushing syndrome or with periodic hormonogenesis. In these cases, continuing follow-up and repeat testing are necessary to confirm the diagnosis.
Suppressed cortisol values may also be observed in primary adrenal insufficiency and hypopituitarism. However, many normal individuals may also exhibit a very low 24-hour urinary cortisol excretion with considerable overlap with the values observed in pathological hypocorticalism. Therefore, without other tests, 24-hour urinary cortisol measurements cannot be relied upon for the diagnosis of hypocorticalism.
Understand and improve your laboratory results with our health dashboard.
Upload your lab reports and get your interpretation today.
Our technology helps to understand, combine, track, organize, and act on your medical lab test results.
Most patients with Cushing syndrome have increased 24-hour urinary excretion of cortisol. Further studies, including suppression or stimulation tests, measurement of serum corticotrophin concentrations, and imaging are usually necessary to confirm the diagnosis and determine the etiology.
Interpret Your Lab Results
Upload your lab report, and we'll interpret and provide you with recommendations today.
Get StartedMonthly plan
Annual plan
Own it for life
Our exclusive data entry service is a convenient way to get your results into your private dashboard. Simply attach an image or a file of your lab test results, and one of our qualified data entry team members will add the results for you. We support all sorts of files, whether PDFs, JPGs, or Excel. This service is excellent whether you have a lot of reports to upload or are too busy to do the data entry yourself.
We strive to make the data entry process easy for you. Whether by offering dozens of templates to choose from that pre-populate the most popular laboratory panels or by giving you instant feedback on the entered values. Our data entry forms are an easy, fast, and convenient way to enter the reports yourself. There is no limit on how many lab reports you can upload.
$15 /month
billed every month
Most popular
Data entry included
$79 /year
$6.60/month billed annually
Data entry included
$250 /once
own it for life
Are You a Health Professional?
Get started with our professional plan
Welcome to Healthmatters Pro.
Save time on interpreting lab results with the largest database of biomarkers online. In-depth research on any test at your fingertips, all stored and tracked in one place. Learn more
Pro Monthly Plus
for health professionals
$75 per month
At HealthMatters, we're committed to maintaining the security and confidentiality of your personal information. We've put industry-leading security standards in place to help protect against the loss, misuse, or alteration of the information under our control. We use procedural, physical, and electronic security methods designed to prevent unauthorized people from getting access to this information. Our internal code of conduct adds additional privacy protection. All data is backed up multiple times a day and encrypted using SSL certificates. See our Privacy Policy for more details.
21-Hydroxylase Antibodies, Acetylcholine Receptor Ganglionic (Alpha 3) AB, Adamts13 Activity, Alpha 2 Antiplasmin, Ana Pattern, AnaChoice Screen, Arachidonic Acid, B2 GLYCOPROTEIN I (IGA)AB, B2 GLYCOPROTEIN I (IGG)AB, B2 GLYCOPROTEIN I (IGM)AB, Beta 2 Transferrin, CARNITINE ESTERS, Chromogranin A (CgA), COPEPTIN, Cortisol, Free, Urine, CORTISOL,FREE,LC/MS,S, DNA Ab (ds) Crithidia, IFA, EPA/ARACHIDONIC ACID Ratio, ESTERIFIED/FREE RATIO, ESTRADIOL (Quest), GLUCOSE-6-PHOSPHATE DEHYDROGENASE, Glutamic Acid Decarboxylase 65 AB, Helicobacter Pylori, Urea Breath Test, Hexagonal Phase Confirm, HISTAMINE RELEASE (CHRONIC URTICARIA), HISTAMINE, PLASMA, IGF 1, LC/MS, IMMUNOGLOBULIN M, Immunoglobulin Subclass 4, LH, Lithium, LKM-1 Antibody (IgG), LUPUS ANTICOAGULANT, Metanephrine, Free, Mutated Citrullinated Vimentin (MCV) Ab, Neuron Specific Enolase (NSE), Normetanephrine, Free, NT PROBNP, OMEGA 3 (EPA+DHA) INDEX, OMEGA 6/OMEGA 3 Ratio, Parathyroid Hormone, intact, PARTIAL THROMBOPLASTIN TIME, ACTIVATED, PREGNENOLONE, LC/MS, PROGESTERONE, LC/MS, PROSTAGLANDIN D2 (PG D2), URINE, Prostaglandin E2, Serum/Plasma, PROSTAGLANDINS (PG D2), SERUM/PLASMA, PROSTAGLANDINS: (PLASMA/SERUM), PROTHROMBIN ANTIBODY (IGG), Ribosomal P Antibody, Soluble Liver Antigen (SLA) Autoantibody, T3 REVERSE, LC/MS/MS, T3, FREE, Total Glutathione, Total, Free (MN+NMN), TRYPTASE, TSI - Thyroid-Stimulating Immunoglobulin, Serum, Vascular Endothelial Growth Factor (VEGF), Z SCORE (FEMALE), Z SCORE (MALE)