Tests starting with the letter O/Ö
Laboratory Test Guide: Tests Beginning with the Letters "O" and "Ö"
A complete list of all tests beginning with the letters "O" and "Ö" performed at Egemed Hospitals’ Medical Laboratories is provided below. To help our patients understand these tests in advance, a brief medical description of each test group and its intended laboratory use are clearly stated.
Biochemistry and Metabolism Tests
Oxalate in a 24-Hour Urine Sample
Description: This test measures the amount of oxalate crystals—one of the primary causes of kidney stone formation in the body—excreted by the kidneys over a 24-hour period.
Purpose: This test is ordered to assess the risk of recurrent kidney stones and to diagnose rare inherited metabolic disorders such as primary hyperoxaluria.
OXALATE (Serum)
Description: A precise analysis of the amount of oxalate molecules present in a free state in the bloodstream (serum) that cannot be excreted in the urine.
Purpose: To detect and monitor the deposition of oxalate in other organs (systemic oxalosis) in patients with severe renal failure.
Oxalate in Urine
Description: This is a rapid oxalate test performed by measuring the creatinine ratio in a single (spot) urine sample collected at any time of the day.
Purpose: To perform a rapid screening for the risk of kidney stones, particularly in infants and children where 24-hour urine collection is difficult.
OSMOLALITY, Urine
Explanation: This is a highly specific measurement that indicates the total concentration of all particles (sodium, potassium, urea, etc.) present in a dissolved state in urine.
Purpose: This test is used to evaluate the kidneys’ ability to concentrate or dilute urine and to determine the body’s rate of fluid loss.
OSMOLALITY, Serum
Description: This test involves calculating the total particle concentration in the blood to accurately analyze the body’s fluid balance and electrolyte levels.
Purpose: It plays a vital role in the diagnosis of severe fluid loss (dehydration), water intoxication, and antidiuretic hormone disorders such as "diabetes insipidus."
Immunology and Neurology (Neuroimmunology) Panels
OLIGOCLONAL BAND ANALYSIS (IEF)
Description: This test involves screening for specific antibody bands (IgG) produced by the immune system in cerebrospinal fluid (CSF) and a concurrent blood sample using the isoelectric focusing (IEF) method.
Purpose: This is the gold standard test used to definitively diagnose multiple sclerosis (MS) and chronic inflammatory conditions of the central nervous system (encephalitis).
AUTOIMMUNE LIVER ANTIBODY PROFILE
Description: This test involves screening for a broad panel of autoantibodies that result from the immune system going out of control and attacking the person’s own liver cells and bile ducts.
Purpose: To definitively distinguish between "autoimmune hepatitis" and "primary biliary cholangitis"—conditions in which the body attacks itself—and viral hepatitis (such as hepatitis B or C).
AUTOIMMUNE LIMBIC ENCEPHALITIS PANEL
Description: This is an advanced, highly specific test that detects the presence of antibodies in the blood that cause neurological damage by targeting cells in the "limbic" region of the brain, which regulates memory, emotion, and behavior.
Objective: To diagnose autoimmune encephalitis, a condition characterized by unexplained, persistent seizures (epilepsy), sudden memory loss, and severe psychiatric symptoms.
AUTOIMMUNE LIMBIC ENCEPHALITIS PANEL, CSF
Description: This procedure involves collecting and analyzing autoantibodies that attack the brain directly from the target site—that is, from the cerebrospinal fluid (CSF).
Purpose: To definitively confirm autoimmune or cancer-related (paraneoplastic) brain inflammation that is actively ongoing within the nervous system, even if blood test results are negative.
Hematology and Genetic (DNA) Tests
OSMOTIC FRAGILITY (Incubated)
Description: This is a laboratory test to determine how easily red blood cells (erythrocytes) break down (their resistance to hemolysis) after being incubated for 24 hours in solutions with reduced salt concentration.
Purpose: This test is used to diagnose hemolytic disorders caused by congenital abnormalities of the cell membrane, particularly "hereditary spherocytosis."
OSTEOGENESIS IMPERFECTA (COL1A1)
Description: This test screens for hereditary DNA mutations in the "COL1A1" gene at the molecular level that disrupt the production of Type 1 collagen, the protein responsible for bone strength.
Objective: To establish a definitive genetic diagnosis of Osteogenesis Imperfecta—commonly known as “Brittle Bone Disease”—which is characterized by frequent bone fractures, and to identify risks within the family.