The human body is comprised of approximately 60% water, and several types of fluids contribute to that number. Given our anatomy's majority aqueous state, body fluid testing is integral to diagnosing and managing a multitude of medical conditions. Here, we'll review common biofluid tests, how they are conducted and the insights they provide into a patient’s health status.
Types of body fluid tests
Body fluid tests are valuable tools for assessing a patient’s well-being, especially when symptoms aren't initially present, and diagnosing various medical conditions affecting different organ systems. While healthcare providers often rely on blood and urine samples for diagnostic purposes, other biofluids are equally beneficial. Some of the most common bodily fluids assessed are:
- Peritoneal fluid in the space (peritoneum) between membranes that line the belly
- Pericardial fluid in the sac (pericardium) surrounding the heart
- Pleural fluid in the space between the membranes that separate the chest and the lungs
- Synovial fluid in joints such as knees, shoulders and hips
- Fluid from the genital area, such as semen or cervical mucus
How are body fluid tests done?
In most cases, this form of diagnostic testing involves extracting samples using a needle from the specific fluid source. However, for genital tests, specimens are collected through swabs or direct fluid sampling. For example, a doctor collects cervical mucus from the vagina or cervix in a way similar to a Pap test (Pap smear).
Learn more about the importance of cervical screenings.
What can the results of body fluid tests reveal?
Biofluid test results can identify signs of infection or inflammation. For example, Gram stain and culture and sensitivity analyses can determine the type of bacteria causing an infection and what medication will best treat it. Additionally, these screenings can detect cancer or other diseases. Here are some other indicators providers can garner from the most common fluid tests:
- The results of peritoneal fluid tests look for bacteria, white and red blood cells, protein and glucose. They can also show the cause of fluid buildup, which can include infection, heart failure, cirrhosis and kidney disease.
- Pericardial fluid may indicate why the fluid is building up around the heart. Reasons can include infection, chest trauma, heart failure and kidney problems.
- Pleural fluid can help diagnose pneumonia, tuberculosis (TB), fungus or other infections. Tests could also show signs of lung cancer.
- Synovial fluid may reveal uric acid-derived crystals that are a sign of gout. A cell count test of the fluid can show if there is an increase in certain types of white blood cells. That could be a sign of an infection or rheumatoid arthritis. Glucose levels in the fluid also can help a doctor diagnose osteoarthritis or rheumatoid arthritis.
- Fluid from the genital area looks for bacteria and other viruses that cause infections, such as HPV, chlamydia, gonorrhea, genital herpes or yeast infections.
Final remarks
From joint problems to infections, body fluid tests are crucial to understanding the complexities of many medical conditions. Doctors can make better decisions and create treatment plans tailored to each patient's needs using the information from these tests.
If you have questions about preparing for or scheduling a body fluid test, speak with your primary care provider. Visit our website to schedule your appointment or call our 24/7 access line at 877-PPG-TODAY. Additionally, Parkview Health Laboratories offers direct access testing (DAT) for select lab tests, eliminating the need for a physician's order.
Copyrighted material adapted with permission from Healthwise, Incorporated. This information does not replace the advice of a doctor.
