Cortisol in urine



Test Description:

In response to a stimulus such as stress, the hypothalamus secretes corticotropinreleasing
hormone. This hormone stimulates the secretion of adrenocorticotropic
hormone (ACTH) by the anterior pituitary gland. ACTH, in turn, causes the adrenal
cortex to release the glucocorticoid hormone, cortisol. Cortisol has several functions,
including:

          • stimulation of glucose formation (gluconeogenesis)
          • stimulation of stored energy molecular breakdown (fats, proteins, carbohydrates)
          • promotion of sympathetic responses to stressors
          • reduction of inflammation and immune function
          • stimulation of gastric acid secretion
Most of the cortisol present in the body is bound to cortisol-binding globulin and
albumin. Five to ten percent is “free” or unconjugated, and is thus filtered by the
kidneys into the urine. It is the free urinary cortisol which is measured by this test,
which is used to evaluate adrenal function, especially hyperfunction. Generally, the
urinary cortisol level will increase when the plasma cortisol level increases, and will
decrease when the plasma cortisol level decreases. The creatinine level in the
24-hour urine specimen is usually measured along with the urinary cortisol level to
confirm that the urine volume is adequate.

Normal Values

                                        10–100 mcg/24 hour (27.6–276 nmol/day SI units)

 Possible Meanings of Abnormal Values

Increased                                                             Decreased

Amenorrhea                                                       Addison’s disease
Cushing’s syndrome                                          Hypopituitarism
Hyperthyroidism                                               Hypothyroidism
Lung cancer                                                       Renal glomerular dysfunction
Pituitary tumor
Pregnancy
Stress

Contributing Factors to Abnormal Values

• Exercise and stress can affect cortisol levels.
• Drugs which may increase urinary cortisol levels: amphetamines, corticotropin,
estrogens, nicotine, oral contraceptives, spironolactone, synthetic glucocorticoids
(prednisone, prednisolone).
• The drug dexamethasone may decrease urinary cortisol levels.

Interventions/Implications

Pretest
• Explain 24-hour urine collection procedure to the patient.
• Stress the importance of saving all urine in the 24-hour period. Instruct the patient to
avoid contaminating the urine with toilet paper or feces.
• Inform the patient of the presence of a preservative in the collection bottle.

Procedure
• Obtain the proper container containing 10 g of boric acid as preservative from the
laboratory.
• Begin the testing period in the morning after the patient’s first voiding, which is
discarded.

• Timing of the 24-hour period begins at the time the first voiding is discarded.
• All urine for the next 24 hours is collected in the container, which is to be kept refrigerated
or on ice.
• If any urine is accidentally discarded during the 24-hour period, the test must be discontinued
and a new test begun.
• The ending time of the 24-hour collection period should be posted in the patient’s room.
• Gloves are worn whenever dealing with the specimen collection

Posttest
• At the end of the 24-hour collection period, label and send the urine container on ice to
the laboratory as soon as possible.
• Report abnormal findings to the primary care provider.
Clinical Alerts                  
• It is not recommended for this test to be performed if the patient is on prednisone/
prednisolone therapy due to a cross-reactivity with the antibody used in this
assay.

تعليقات

إرسال تعليق

المشاركات الشائعة من هذه المدونة

Anti-Parietal Cell Antibody

Test Description The anti-parietal cell antibody test (APCA) measures the presence of antibodies against gastric parietal cells. When antibodies form against the parietal cells in the stomach, their production of intrinsic factor is disrupted. This results in pernicious anemia due to an autoimmune process. Thus the APCA test is used in the evaluation of pernicious anemia. It may be elevated in atrophic gastritis and in some other autoimmune processes. Normal Values Negative Possible Meanings of Abnormal Values Positive CREST syndrome Scleroderma Contributing Factors to Abnormal Values • Drugs that may increase antiscleroderma antibody levels: aminosalicylic acid, isoniazid,   methyldopa, penicillin, propylthiouracil, streptomycin, tetracycline.    Interventions/Implications Pretest • Explain to the patient the purpose of the test and the need for a blood sample to be drawn. • No fasting is required before the test. Procedure • A 7-mL bl...
قراءة المزيد

انواع تحاليل السكر

1- تحليل السكر العشوائي  R.B.S { Random Blood Glucose }  فائدته فقط أنه يعطي فكرة عامة عن مستوى السكر في دم المريض حيث يتم تحليل العينة في أي وقت خلال اليوم ، سواء لمريض السكر أو الشخص السليم وتؤخذ نتائج هذا التحليل إلى الطيبب ليقوم بتقييم حالة المريض. 2- تحليل سكر الصائم: F.B.S { Fasting Blood Glucose }   يجرى هذا التحليل على المريض بحيث يكون صائمآ من 6 – 8 ساعة علمآ أن المستوى الطبيعي للسكر في الدم يتراوح ما بين 70 – 110 مجم لكل 100ملليتر دم، فإذا زادت النسبة عن 120 فهذا مؤشر لحدوث الاصابة بالسكر في المستقبل، وإذا تجاوزت 130 فهذا يعتبر مريضآ بالسكر، ويتم التأكد من ذلك بإعادة التحليل لمرتين أو 3 مرات متتابعة على الأقل بفاصل اسبوع بين كل قياس.  3- تحليل السكر بعد ساعتين من الأكل  P.P.S { Post Prandial Sugar } يتم هذا التحليل على المريض بعد وجبة طبيعية ( أو 75 جرام جلوكوز) ثم نقيس له السكر في الدم بعد ساعتين من الاكل ، وفائدة هذا التحليل أنه يعطينا فكرة عن مستقبل حدوث مرض السكر عند هذا المريض وهل سوف يحتاج إلى تحليل منحنى السكر أو لا. فإذا تجاوز...
قراءة المزيد