Tests starting with the letter G
Laboratory Test Guide: Tests Starting with the Letter "G"
A complete list of all tests beginning with the letter "G" performed at Egemed Hospitals’ Medical Laboratories is provided below. To help our patients understand these tests, a brief medical description and the laboratory’s intended use for each test group are clearly stated.
Microbiology and Stool (Fecal) Analyses
Fecal Microscopy
Description: This involves the direct examination of a stool sample under a microscope and the cultivation of pathogenic (disease-causing) bacteria by inoculating them onto specialized laboratory culture media.
Purpose: This test is used to identify the causative bacterial agent in cases of bloody, mucus-containing, or prolonged severe diarrhea (such as those caused by Salmonella or Shigella) and to select the appropriate antibiotic (based on antibiotic susceptibility testing).
Adenovirus Antigen in Stool
Rotavirus Antigen in Stool
Description: This test uses rapid testing methods to detect the structural proteins (antigens) of the two most common viruses that cause intestinal infections in a stool sample.
Objective: To rapidly identify the viral cause of epidemic diarrhea (acute gastroenteritis), particularly in infants and children, and thereby prevent the unnecessary use of antibiotics.
in Stool Giardia Antigen in Stool
Description: This procedure involves searching for cellular fragments of intestinal parasites (Entamoeba histolytica and Giardia lamblia) in stool samples, which may not always be visible under a microscope.
Purpose: This test is ordered to definitively diagnose parasitic infections that cause dysentery, chronic diarrhea, abdominal pain, and bloating.
Helicobacter Pylori Antigen in Stool
Description: This test measures the excretion of proteins from the H. pylori bacterium—which colonizes the stomach and is resistant to acid—in the stool.
Purpose: To diagnose suspected gastric ulcers and gastritis without the need for endoscopy (using a non-invasive method) and to verify whether the bacteria have been completely eradicated following treatment.
Blood in the Stool
Description: This involves the detection of microscopic amounts of blood in the stool—too small to be seen with the naked eye—through chemical reactions.
Purpose: It is the primary screening test for the early detection of colon (large intestine) cancer, intestinal polyps, and gastrointestinal bleeding (such as ulcers).
Stool Digestion Analysis Stool Digestion
Description: This involves the microscopic examination of stool samples to detect undigested fat droplets, muscle (meat) fibers, and starch residues from ingested food.
Purpose: This test is ordered to evaluate pancreatic insufficiency, bile duct disorders, or malabsorption in the small intestine.
Reducing Agent in Feces
Description: This procedure involves the detection of sugars (particularly carbohydrates such as lactose and galactose) that pass directly into the stool because they cannot be digested in the intestines.
Purpose: It is used to diagnose lactose intolerance and glucose-galactose malabsorption, particularly in newborns and children.
Gruber-Widal Test
Description: This test measures the antibodies formed in the patient’s blood (serum) against Salmonella bacteria using the agglutination method.
Purpose: This test is used for the serological (blood) diagnosis of typhoid and paratyphoid infections characterized by prolonged, persistent fever and diarrhea.
Group A Streptococcus test
Description: This is a rapid screening test that detects the antigen of "Group A Beta-Hemolytic Streptococcus" bacteria within minutes using a swab taken from the tonsils or throat.
Objective: To provide an urgent diagnosis of severe throat infections, commonly known as "strep throat," which can lead to rheumatic fever if left untreated.
Biochemistry, Hormone, and Metabolism Tests
Glucose (Fasting Blood Glucose)
Description: This is a measurement of the primary sugar in the bloodstream—the body’s main source of energy—taken after an 8- to 10-hour fast (fasting blood sugar).
Purpose: This is a basic test used to diagnose diabetes, screen for the risk of insulin resistance, and monitor blood sugar control in patients with existing diabetes.
Glucose-6-phosphate dehydrogenase
GLUCOSE-6-PHOSPHATE DEHYDROGENASE (G6PD)
Description: This test measures the blood level of a vital enzyme that protects red blood cells (erythrocytes) against cellular stress and breakdown (hemolysis).
Purpose: To diagnose the genetic cause of acute hemolysis and anemia that develops following the consumption of fava beans (favism) or the use of certain medications (such as some antibiotics and antimalarial drugs).
Growth Hormone
Description: A hormone (somatotropin) secreted by the pituitary gland at the base of the brain that regulates bone growth and cell regeneration.
Purpose: This test is ordered to diagnose developmental delay (dwarfism) or excessive growth (gigantism) in children, and "acromegaly"—a condition characterized by enlargement of the hands and face—in adults.
Immunology, Allergy, and Neurology Panels
GANG LIOSIDE ANTIBODY PANEL IgG
GANGLIOSIDE ANTIBODY PANEL IgG, CSF
GANGLIOSIDE ANTIBODY PANEL IgM
GANGLIOSIDE ANTIBODY PANEL IgM, CSF
Description: This test screens for neurological autoantibodies produced by the body against "ganglioside" molecules found in the protective sheath (myelin) of peripheral nerves, both in the blood and in cerebrospinal fluid (CSF).
Purpose: This study aims to establish a definitive diagnosis of autoimmune neurological disorders such as Guillain-Barré Syndrome (GBS) and Miller Fisher Syndrome, which are characterized by sudden-onset muscle weakness and paralysis.
GLUTEN (F79) CLIA
Description: This test measures the levels of specific allergic (IgE) antibodies produced by the body in response to the gluten protein found in grains such as wheat, barley, and rye, using the chemiluminescence immunoassay (CLIA) method.
Purpose: This test is requested to diagnose "wheat/gluten allergy," which develops independently of classic celiac disease.
Genetic and Molecular (PCR) Analyses
GALACTOSEMIA GENETIC ANALYSIS (GALTgen)
Description: This involves the molecular-level screening for disease-causing mutations in the gene encoding the GALT enzyme, which breaks down galactose—a type of milk sugar—in the body.
Purpose: To establish a definitive diagnosis of hereditary galactosemia, a condition that causes liver failure, cataracts, and intellectual disability in newborns.
EYE INFECTION PCR PANEL
Description: This is a multiplex PCR test that simultaneously screens for the DNA of numerous pathogens (such as adenovirus, HSV, CMV, Chlamydia, etc.) that cause eye infections in eye fluids or conjunctival swabs.
Objective: To identify the underlying cause of persistent and severe eye infections—such as keratitis or uveitis—that carry a risk of blindness within hours, thereby initiating treatment to save the eye.