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Detection of a fake or adulterated urine sample is necessary before going to the further process of urine testing in the laboratory. Urine adulteration causes false-positive and false-negative results. However, most attempts of a fake or adulteration in a urine sample can be detected either by a trained collection site…
The peritoneal cavity is a potential space in the abdomen lined by mesothelial cells and normally containing about 30-50 ml of serous fluid. The fluid is an ultrafiltrate of plasma and its formation is dependent upon hydrostatic pressure, plasma oncotic pressure, and capillary permeability.
It is a clear, colorless fluid formed in the ventricles of the brain mainly by choroid plexus (an interlaced structure or meshwork of tiny small blood vessels in the lateral third and fourth ventricles). It is mainly an ultrafiltrate of plasma.
Waste products excreted from the digestive tract are composed of water (up to 75%), indigestible residue, undigested food, food which is digested but not absorbed, bile, epithelial cells, secretions from the digestive tract, inorganic material, and bacteria. The normal amount of feces in an adult is 100-200 grams per day.…
Collection of sample This test is performed with the patient's serum. There is no restriction for a fasting sample. The test can be done by a random blood sample the patient. About 3 to 5 ml of blood is collected in a plain test tube, and blood is allowed to…
Why is this test performed? This test is performed for the diagnosis and differentiation of jaundice. This test is also done in a patient with hemolytic anemia in adult and newborn. This test is very useful to evaluate liver functions and for the follow-up of a patient with treatment. Collection…
Why is this test performed? This test is evaluated in different conditions and diseases such as nephrotic syndrome, liver diseases, kidney diseases, in a patient suspected of malnutrition, and patients severe burn. See also: Procedures for the collection of blood for hemotological investigations. Collection of sample For the estimation of…
Why is this test performed? This hormone test is evaluated in different conditions, such as Hyperaldosteronism, Cushing's syndrome and Virilizing syndrome. Lab tests for various adrenal abnormalities Primary Adrenal Insufficiency (Addison's disease): This is due to the diseases of the gland. Level of sodium in serum is low. Cortisol level…
Total serum thyroxine includes both free and protein-bound thyroxine and is usually measured by competitive immunoassay. Normal level in adults is 5.0-12.0 μg/dl. Test for total thyroxine or free thyroxine is usually combined with TSH measurement and together they give the best assessment of thyroid function. Causes of…
Among the endocrine disorders, disorders of the thyroid are common and are only next in frequency to diabetes mellitus. They are more common in women than in men. Functional thyroid disorders can be divided into two types depending on the activity of the thyroid gland: hypothyroidism (low thyroid hormones), and…
The ovaries are the sites of production of female gametes or ova by the process of oogenesis. The ova are released by the process of ovulation in a cyclical manner at regular intervals. Ovary contains numerous follicles that contain ova in various stages of development. During each menstrual cycle, up…
The male reproductive system consists of testes (paired organs located in the scrotal sac that produce spermatozoa and secrete testosterone), a paired system of ducts comprising of epididymis, vasa deferentia, and ejaculatory ducts (collect, store, and conduct spermatozoa), paired seminal vesicles and a single prostate gland (produce nutritive and lubricating…
Anatomically, stomach is divided into four parts: cardia, fundus, body, and pyloric part. Cardia is the upper part surrounding the entrance of the esophagus and is lined by the mucus-secreting epithelium. The epithelium of the fundus and the body of the stomach is composed of different cell types including: (i)…
Hollander’s test (Insulin hypoglycemia test): In the past, this test was used for confirmation of completeness of vagotomy (done for duodenal ulcer). Hypoglycemia is a potent stimulus for gastric acid secretion and is mediated by vagus nerve. This response is abolished by vagotomy. In this test, after determining BAO, insulin…
Gastric intubation for gastric analysis is contraindicated in esophageal stricture or varices, active nasopharyngeal disease, diverticula, malignancy, recent history of severe gastric hemorrhage, hypertension, aortic aneurysm, cardiac arrhythmias, congestive cardiac failure, or non-cooperative patient. Pyloric stenosis: Obstruction of gastric outlet can elevate gastric acid output due to raised gastrin (following…
In gastric analysis, amount of acid secreted by the stomach is determined on aspirated gastric juice sample. Gastric acid output is estimated before and after stimulation of parietal cells (i.e. basal and peak acid output). This test was introduced in the past mainly for the evaluation of peptic ulcer disease…
