Synovial fluid crystals analysis

Your healthcare practitioner may order a synovial fluid crystals analysis to diagnose the type of inflammatory disease affecting your joints, primarily gout and CPPD disease.

Some of the symptoms associated with gout are:

• Swelling in a joint
• Redness around a joint
• Joint pain or soreness
• Pain and swelling in a big toe, ankle or knee
• Joints warm to touch
• Reddish or purple discolouration of the skin

Gout symptoms occur as the attack and may last for three to ten days after which they are resolved spontaneously.

The symptoms of CPPD disease are similar to those of gout and include:

• Pain in the joints 
• Swelling of joints
• Redness of the skin around the joint 
• A feeling of warmth in the affected joint

Fasting may be required before this test. Also, your doctor may ask you to avoid vigorous exercise sometime before the test.

In case you are taking any prescribed, non-prescribed, illicit or herbal medicines, or vitamins and supplements, please let your doctor know about them. Your doctor may advise you to discontinue some medicines before the test. Do not stop taking any medicine on your own.

The following medications and conditions may affect the test results:

• Purine-rich foods, such as mushrooms, dried peas and beans, organ meats, seafood and fish
• Aspirin
• Levodopa
• Cyclosporine
• Vitamin B3
• Chemotherapy or radiotherapy
• Diuretics

Your doctor will use a procedure called arthrocentesis or joint aspiration to withdraw a small amount of synovial fluid from your body. Here is how it will be done: 

• Your doctor will ask you to sit or lie down in a comfortable position so he gets easy access to the joint. Joint aspiration is mostly done on the knee.
• He/she will inject a medicine to numb the area around the joint. 
• Once the area is numb, the doctor will clean the skin over the joint and the surrounding area and insert a needle to collect the fluid.
• An ultrasound is sometimes used to guide the needle.
• Once the required amount of fluid is collected the doctor will withdraw the needle and cover the area with a bandage.
• He/she will then label the sample and send it to the laboratory for testing.

You may feel slight pain in the joint area after the procedure, though it will go away after a few hours. In rare cases, an infection, excess bleeding or an allergic reaction occurs at the needle insertion site. Talk to your doctor if any of you notice persistent discomfort. 

Normal results:

A healthy person does not have any crystals in their synovial fluid.

Abnormal results:

An abnormal result is reported when any crystals are seen in the synovial fluid. The joint disease is diagnosed based on the shape of the crystals seen. For example, uric acid crystals seen in gout are often needle-shaped, while calcium pyrophosphate crystals in CPPD disease are usually rhomboidal in shape.

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.