What does synovial fluid analysis primarily test for?

Synovial fluid analysis primarily tests for the presence of crystals and joint infection because this fluid is found in the cavities of synovial joints and serves several important functions, including lubrication and nourishment of the joint structures. The analysis of this fluid can provide critical information about various joint disorders.

For instance, the presence of urate crystals can indicate gout, while calcium pyrophosphate crystals are associated with pseudogout. Additionally, testing for infection involves looking for white blood cells and bacteria, which can signal conditions such as septic arthritis. Therefore, synovial fluid analysis is a key diagnostic tool in evaluating joint inflammation, infections, and other related disorders, making the first choice the most appropriate answer.

The other options focus on different types of bodily fluids or tests that do not relate to joint analysis: red blood cell count and hemoglobin levels pertain to blood tests, semen volume and sperm count relate to reproductive health, and abnormal hemoglobin examination is associated with conditions like sickle cell disease and thalassemia, none of which are relevant to synovial fluid analysis.