Medical Tests and Their Indicators

A test that detects hidden blood in stool. It can be used to screen for colorectal issues like colon cancer.

Non-invasive (no surgery) and relatively cheap.

Only detects blood, not the cause. Can have false positive or negative results.

Detects human chorionic gonadotropin (hCG) in urine or blood, a hormone produced during pregnancy.

First morning urine usually has the highest concentration of hCG.

The human body contains 1-2 kg of calcium, with 99% located in bones. Calcium exists in three forms: ionized (biologically active), protein-bound (inactive), and complexed (bound to anions).

The normal range for total calcium in blood is 8.8-10.4 mg/dL (2.2-2.6 mmol/L). This reflects the combined levels of all calcium forms.

Factors that influence calcium absorption include acidic pH, vitamin D, parathyroid hormone (PTH), and a high protein diet.

Ionized calcium represents 50% of circulating calcium and is the biologically active form. It is diffusible, meaning it can move freely across cell membranes.

Complexed calcium accounts for 10% of circulating calcium and is bound to ions like phosphate, bicarbonate, and citrate. It is also diffusible.

Protein-bound calcium represents 40% of circulating calcium and is biologically inactive. It is not excreted and not freely diffusible.

Hypocalcemia is a decrease in total plasma calcium levels. It can lead to hyper-excitability of the neuromuscular junction, causing symptoms like pins and needles, tetany, paralysis, and convulsions.

Hypercalcemia is an increase in total plasma calcium levels. It can cause kidney damage, calcium stones, constipation, dehydration, tiredness, and depression.

A test that measures the level of calcium in urine. It helps diagnose conditions like kidney stones or hyperparathyroidism.

A positive result indicates calcium presence in the urine, causing cloudiness or precipitate formation.

A negative result indicates no detectable calcium in the urine.

Measures the amount of chloride ions in blood or urine. It assesses fluid balance and electrolyte levels.

Can be caused by dehydration, excessive salt intake, kidney disease or parathyroidism.

Minerals like chloride that carry an electric charge in bodily fluids. They maintain fluid balance and regulate many bodily functions.

The proper distribution of water between body compartments (intracellular and extracellular).

The force of blood pushing against the walls of blood vessels.

This occurs when the body retains too much water, often due to conditions like SIADH, Addison's disease, metabolic alkalosis, heart failure, and persistent vomiting.

This test checks for the presence of chloride in urine by reacting it with silver nitrate and nitric acid, forming a white precipitate if positive.

This part of urinalysis examines urine under a microscope to detect insoluble substances that might indicate renal disorders.

This helps identify and quantify insoluble substances in urine, providing valuable information for diagnosing renal diseases.

Specimen preparation, volume, and centrifugation are crucial for reliable results in microscopic urine examination.

Combining physical, chemical, and microscopic urine examination findings is crucial for accurate and valid results.

It is the most time-consuming part of urinalysis but essential for detecting insoluble substances in urine that might indicate renal disorders.

Specimen preparation, volume, and the centrifugation process are all crucial factors to consider for an accurate and reliable microscopic examination.

A laboratory test that examines urine sediment under a microscope to identify cells, casts, crystals, and other components.

The solid particles that settle at the bottom of a urine sample after centrifugation.

May indicate bleeding in the urinary tract, ranging from mild irritation to serious conditions.

High WBC counts suggest infection or inflammation in the urinary tract.

Cells lining the urinary tract, usually present in small numbers. Increased amounts can indicate irritation, infection, or other conditions.

Tiny molds of the tubules in the kidneys, formed from protein and other substances. Their presence can indicate kidney disease.

Can form in the urine due to various factors, often harmless but some may indicate kidney stones or other issues.

Can indicate a urinary tract infection (UTI), a common infection in the bladder or kidneys.

A hormone produced by the placenta during pregnancy. It's detectable in urine, blood, and other body fluids.

Pregnancy tests can be biological (using animal tests) or immunological (using antibodies).

This test uses latex particles coated with HCG to detect pregnancy. The presence of HCG in the sample prevents agglutination (clumping).

The latex particles do not clump, indicating the presence of HCG and therefore pregnancy.

The latex particles clump, indicating the absence of HCG, and therefore no pregnancy.

HCG helps confirm pregnancy, investigate abortions, and differentiate pregnancy from other conditions like a hydatidiform mole.

The test requires HCG-bound latex particles, anti-HCG antibody reagent, and positive and negative controls.

A drop of urine is added to a test plate, followed by a drop of anti-HCG reagent and HCG-bound latex particles.