Syndrome of Inappropriate Antidiuretic Hormone (SIADH)
SIADH is a condition in which the body makes too much antidiuretic hormone (ADH), leading to water retention and low blood sodium levels (hyponatremia). It can be caused by various underlying conditions.
Common Symptoms
- Nausea
- Vomiting
- Headache
- Confusion
- Weakness
Clinical Sources
- SIADH (Syndrome of Inappropriate Antidiuretic Hormone Secretion)Cleveland Clinic
- Hyponatremia: Causes, Symptoms, Diagnosis & TreatmentCleveland Clinic
Diagnostic Lab Tests
Tests commonly used to diagnose or monitor Syndrome of Inappropriate Antidiuretic Hormone (SIADH):
Urine Sodium
Sodium is the primary extracellular electrolyte responsible for maintaining osmotic pressu...
Chloride
Chloride is the major extracellular anion and works closely with sodium to maintain osmoti...
Urine Specific Gravity
Urine Specific Gravity (USG) measures the concentration of particles in the urine compared...
TSH Receptor Antibody
TSH Receptor Antibodies (TRAb) are autoantibodies that bind to the thyroid-stimulating hor...
Chlorides
Chloride is one of the most important electrolytes in the blood. It helps maintain the bal...
Urine Osmolality
Urine Osmolality is a precise measurement of the concentration of dissolved particles in t...
Osmolality (Serum)
Serum Osmolality measures the concentration of dissolved particles in the blood, primarily...
Serum Cortisol
Cortisol is often referred to as the 'stress hormone' and is a vital steroid hormone produ...
Platelet Count (PLT)
Platelets (thrombocytes) are specialized cell fragments essential for hemostasis (blood cl...
Free T3, Free T4
Free T3 (Triiodothyronine) and Free T4 (Thyroxine) are the 'active' forms of thyroid hormo...
Chloride, Urine
Urine Chloride is a vital measurement for evaluating the body's acid-base balance and elec...
Thyroglobulin Levels
Thyroglobulin (Tg) is a large glycoprotein produced exclusively by the follicular cells of...
Carcinoembryonic Antigen (CEA)
CEA is a glycoprotein involved in cell adhesion. While primarily associated with colorecta...
Chloride
Serum Chloride is a major extracellular anion that works closely with sodium, potassium, a...
Serum CEA (Carcinoembryonic Antigen)
Carcinoembryonic Antigen (CEA) is a glycoprotein involved in cell adhesion. It is normally...
Urine Potassium
Potassium is a vital electrolyte essential for nerve conduction, muscle contraction, and m...
Aldosterone-Renin Ratio
The Aldosterone-Renin Ratio (ARR) is the most reliable screening test for Primary Aldoster...
Potassium
Potassium is a critical mineral and electrolyte that facilitates nerve transmission and th...
Benedict's Test
Benedict's test is a biochemical assay used to detect the presence of reducing sugars in t...
Urine For Sugar
The 'Urine for Sugar' test, commonly referred to as a glucose urine test, measures the amo...
Serum Progesterone
Progesterone is a steroid hormone primarily produced by the corpus luteum in the ovaries d...
Osmolality (Urine)
Urine osmolality is a measure of the concentration of particles dissolved in the urine, pr...
Glucose
Glucose is the primary source of energy for the body's cells and the only energy source fo...
Anti Thyroglobulin Antibodies
Anti-Thyroglobulin (Anti-Tg) antibodies are autoantibodies produced by the immune system t...
Carcinoembryonic Antigen
Carcinoembryonic Antigen (CEA) is a glycoprotein involved in cell adhesion. It is normally...
Serum Electrolytes
Electrolytes are electrically charged minerals found in your blood and other body fluids. ...
Thyroid Stimulating Hormone
Thyroid Stimulating Hormone (TSH), also known as thyrotropin, is produced by the anterior ...
Aldosterone
Aldosterone is a steroid hormone produced by the adrenal cortex. Its primary function is t...
Thyroid Peroxidase Antibodies (TPOAb)
Thyroid Peroxidase (TPO) is an enzyme normally found in the thyroid gland that plays a cru...
Plasma Renin Activity
Plasma Renin Activity (PRA) measures the capacity of the enzyme renin to generate angioten...
Thyroid Stimulating Hormone (TSH)
TSH is a glycoprotein hormone secreted by the anterior pituitary gland to regulate the pro...
Platelet Count
Platelets, or thrombocytes, are small cell fragments in the blood that are essential for n...
Fluid Chlorides
Chloride is a major extracellular anion that helps maintain osmotic pressure, acid-base ba...
Thyroid Stimulating Hormone (TSH)
TSH, produced by the anterior pituitary, is the most sensitive marker for screening thyroi...
Total Cholesterol
Cholesterol is a waxy, fat-like substance found in all cells of the body. It is essential ...
Angiotensin Converting Enzyme
Angiotensin-Converting Enzyme (ACE) is a critical enzyme primarily produced by epithelial ...
Serum Osmolality
Serum osmolality is a measure of the concentration of dissolved particles in the blood, pr...
Lactate Dehydrogenase (LDH)
Lactate dehydrogenase (LDH) is an enzyme found in nearly all living cells. It plays a crit...
Thyroid Stimulating Hormone (TSH)
TSH is produced by the anterior pituitary gland to regulate the production of T4 and T3 by...
Sodium
Sodium is the primary extracellular cation and is essential for maintaining osmotic pressu...
Free Thyroxine (FT4)
Free Thyroxine (FT4) is the active, unbound form of the hormone T4 produced by the thyroid...
BCR/ABL Quantitative PCR
The BCR-ABL1 quantitative test measures the amount of the BCR-ABL1 fusion transcript in th...
TPO Antibodies
Thyroid Peroxidase (TPO) is an enzyme normally found in the thyroid gland that plays a cru...
Sodium
Sodium is the primary extracellular cation and is critical for maintaining osmotic pressur...
Bleeding Time and Clotting Time
The Bleeding Time (BT) and Clotting Time (CT) tests are fundamental screening tools used t...
17-Alpha Hydroxy Progesterone
17-hydroxyprogesterone (17-OHP) is a precursor hormone in the synthesis of cortisol. The e...
Bleeding Time (Ivy Method)
Bleeding Time is a functional test that assesses the primary hemostatic response, which in...
Urine For GTT
The Urine Glucose Tolerance Test (GTT) is performed in conjunction with the oral blood glu...
Uric Acid
Uric Acid is the metabolic byproduct of purine degradation. In an Arthritis Basic Screen, ...
Sodium, Urine (24-Hour)
Urine Sodium measurement is a vital tool in assessing renal handling of electrolytes and v...
Plasma Aldosterone
Aldosterone is a mineralocorticoid hormone produced by the adrenal cortex that regulates s...
Serum Sodium
Sodium is the primary extracellular electrolyte and is vital for maintaining fluid balance...
Blood Pressure
Blood pressure (BP) measures the force of blood pushing against the walls of the arteries....
Amphetamines
This component of a toxicology panel screens for the presence of amphetamine-class stimula...
HIV RNA PCR
The HIV RNA PCR (Polymerase Chain Reaction) test, often called a 'Viral Load' test, is a m...
Specific Gravity
Specific Gravity (SG) measures the ratio of the density of urine to the density of water. ...
Urine Electrolytes
Urine Electrolyte testing measures the concentration of minerals—specifically sodium (Na),...
Urine For Spot Sodium
Sodium is a critical electrolyte that regulates the amount of water in the body and plays ...
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