Laboratory tests

Laboratory tests
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Purpose	Diagnosis, monitoring, and screening of diseases
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Laboratory tests are medical procedures that involve testing samples of blood, urine, or other tissues or substances in the body. These tests are crucial for diagnosing diseases, monitoring health conditions, and guiding treatment decisions. Laboratory tests can provide valuable information about the functioning of organs, the presence of infections, and the levels of various substances in the body.

Types of Laboratory Tests

Laboratory tests can be broadly categorized into several types based on their purpose and the type of sample being tested.

Blood Tests

Blood tests are among the most common laboratory tests. They can measure a wide range of substances in the blood, including glucose, cholesterol, electrolytes, and proteins. Common blood tests include:

• Complete Blood Count (CBC): Measures the levels of different blood cells, such as red blood cells, white blood cells, and platelets.
• Blood Chemistry Tests: Assess the levels of various chemicals in the blood, such as glucose, calcium, and electrolytes.
• Liver Function Tests: Evaluate the health of the liver by measuring enzymes and proteins in the blood.

Urine Tests

Urine tests analyze the content of urine to detect abnormalities. They are often used to diagnose urinary tract infections, kidney disorders, and diabetes. Common urine tests include:

• Urinalysis: A general test that checks for the presence of substances such as proteins, glucose, and ketones in the urine.
• Urine Culture: Identifies bacteria or fungi in the urine that may be causing an infection.

Other Body Fluid Tests

Tests can also be performed on other body fluids, such as cerebrospinal fluid, saliva, and synovial fluid, to diagnose various conditions.

Genetic Tests

Genetic tests analyze DNA to identify changes in genes that may cause or increase the risk of certain diseases. These tests can be used for:

• Carrier Testing: Determines if a person carries a gene for a genetic disorder.
• Prenatal Testing: Detects genetic abnormalities in a fetus.

Purpose of Laboratory Tests

Laboratory tests serve several important purposes in medical practice:

• Diagnosis: Identifying the cause of symptoms and confirming a diagnosis.
• Monitoring: Tracking the progress of a disease or the effectiveness of treatment.
• Screening: Detecting diseases in their early stages before symptoms appear.

Interpreting Laboratory Test Results

Interpreting laboratory test results requires understanding the normal ranges for each test and how various factors can affect these results. Factors such as age, sex, diet, and medications can influence test outcomes. It is important for healthcare providers to consider these factors when interpreting results.

Limitations of Laboratory Tests

While laboratory tests are valuable tools, they have limitations. False positives and false negatives can occur, and test results must be interpreted in the context of the patient's overall health and other diagnostic information.

Also see

• Medical diagnosis
• Clinical pathology
• Biochemistry
• Hematology
• Microbiology