Water Deprivation Test
Precautions: Severe dehydration (hypotension, tachycardia) may occur in patients with true diabetes insipidus. Weight loss should not be allowed to exceed 5 % of initial body weight and blood pressure should…
Seventy Two Hours Fast for Insulinoma
Symptoms, signs, or both Glucose (mg/dl) Insulin (µU/ml) C-peplide (nmol/L) Proinsulin (pmol/L) β-Hydroxy -butyrate (nmol/liter) Glucose increase after glucagon (mg/dl) Circulating oral hypoglycemic Antibody to insulin Diagnostic Interpretation No < 55…
Mixed Meal Hypoglycemia Test
If a patient is symptomatic and blood glucose is normal, diagnosis of postprandial syndrome can be made. Caveats: An oral glucose tolerance test should never be used for the evaluation…
Levothyroxine Absorption Test
Precautions: Supervise patient continuously during the procedure. Interpretation: Absorption is calculated by using the following formula [1]: Volume of distribution (Vd) in deciliters: 4.42 × body mass index [1]. More than 60–80 %…
Intravenous Saline Suppression Test
Assay for Aldosterone: Enzymatic radioimmunoassay (RIA). Precautions: Do not perform this test in patients with severe uncontrolled hypertension, renal insufficiency, cardiac insufficiency, cardiacarrhythmia, or severe hypokalemia. Interpretation: Postinfusion plasma aldosterone…
Thyroid Cancer Follow-Up: Thyrogen Injection with Scan With/Without Treatment
− 14 Day and date Start with low-iodine diet. Continue this diet until after you have your blood work done on Day 5 1 Day and date Have labs (TSH and…
ACTH Stimulation Test for Late Onset (Nonclassic) 21-Hydroxylase Deficiency
Assay for 17 OHP: Radioimmunoassay (RIA) . Interpretation: With late onset 21-hydroxylase deficiency, the absolute value of 17-hydroxyprogesterone at 60 min sample is > 10 ng/dl [2, 3]. Caveats: Baseline androgen levels return…
Combined CRH Dexamethasone Suppression Test
Assay for Cortisol: Chemiluminescence Immunoassay (CLIA) . Precautions: None. Interpretation: Serum cortisol concentration more than 1.4 mcg/dl at 15 min after Combined Dex-CRH test is suggestive of Cushing’s syndrome [1]. Caveats: We…
Glucagon Stimulation Test for GHD (GST)
Assay for GH: Immunoenzymatic Precautions: Nausea (30 %), vomiting/retching (10 %), and headaches (10 %) may occur during and after the test. (Administration of intravenous antiemetics can be considered.) Late hypoglycemia may rarely…
ACTH Stimulation Test for Adrenal Insufficiency with Free Cortisol Levels
Assay for Cortisol: Electrochemiluminescence immunoassay (ECLIA) . Precautions: Cosyntropin is category C of pregnancy. Interpretation: Normal response: Peak stimulated cortisol value > 1.2 mcg/dl [3, 4] at 30 or 60 min. Most…
