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Why is this test performed? This hormone test is evaluated in different conditions, such as Adrenal insufficiency, in Acromegaly and Cushing Syndrome. In Addison's disease, the level of Adrenocorticotropic hormone (ACTH) is noted more than 1000 pg/ml. In Adrenal carcinoma, Adenoma, and Adrenocortical insufficiency, the level of Adrenocorticotropic hormone (ACTH) decreases.…
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…
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…
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…
To assess gastric acid secretion, acid output from the stomach is measured in a fasting state and after injection of a drug which stimulates gastric acid secretion. Basal acid output (BAO) is the amount of hydrochloric acid (HCl) secreted in the absence of any external stimuli (visual, olfactory, or auditory). Maximum acid…
Microscopic examinations done on fecal sample are shown in Figure 846.1. Collection of Specimen for Parasites A random specimen of stool (at least 4 ml or 4 cm³) is collected in a clean, dry, container with a tightly fitting lid (a tin box, plastic box, glass jar, or waxed cardboard…
Chemical examination of feces is usually carried out for the following tests (Figure 845.1): Occult blood Excess fat excretion (malabsorption) Urobilinogen Reducing sugars Fecal osmotic gap Fecal pH Figure 845.1: Chemical examinations done on fecal sample Test for Occult Blood in Stools Presence of blood in feces which is not…
Tests to Assess Proximal Tubular Function Renal tubules efficiently reabsorb 99% of the glomerular filtrate to conserve the essential substances like glucose, amino acids, and water. 1. Glycosuria In renal glycosuria, glucose is excreted in urine, while blood glucose level is normal. This is because of a specific tubular lesion…
Normally, a very small amount of albumin is excreted in urine. The earliest evidence of glomerular damage in diabetes mellitus is occurrence of microalbuminuria (albuminuria in the range of 30 to 300 mg/24 hours). An albuminuria > 300-mg/24 hour is termed clinical or overt and indicates significant glomerular damage. (See…
Two biochemical parameters are commonly used to assess renal function: blood urea nitrogen (BUN) and serum creatinine. Although convenient, they are insensitive markers of glomerular function. Blood Urea Nitrogen (BUN) Urea is produced in the liver from amino acids (ingested or tissue-derived). Amino acids are utilized to produce…
One can estimate GFR from age, sex, body weight, and serum creatinine value of a person from the following formula (Cockcroft and Gault): Creatinine clearance in ml/min = (140 - Age in years) × (Body weight in kg) …
Glomerular filtration rate refers to the rate in ml/min at which a substance is cleared from the circulation by the glomeruli. The ability of the glomeruli to filter a substance from the blood is assessed by clearance studies. If a substance is not bound to protein in plasma, is completely…
Renal biopsy refers to obtaining a small piece of kidney tissue for microscopic examination. Percutaneous renal biopsy was first performed by Alwall in 1944.
