Both diseases have variable manifestations, ranging from asymptomatic disease to severe debilitating illness.
Regardless, the diseases are treatable, but the specific approach will vary from person to person.
Normally, excess uric acid is eliminated in the urine or by the gut.
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Diet and alcohol intake can affect serum uric acid levels as well.
Cartilage cells (chondrocytes) naturally produce a substance called pyrophosphate.
Most uric acid is excreted through the urine and gut.
Conditions that can cause this are common and includeobesity,chronic kidney disease, dehydration, andhypothyroidism.
Less commonly,inherited disorderscan lead to decreased uric acid excretion or increased uric acid production.
Diet can affect uric acid levels in the blood.
Calcium Pyrophosphate Dihydrate Crystals
The causes of CPPD crystal formation in the joints are less well understood.
Crystal formation in the joints may be inherited (familialchondrocalcinosis).
Also, joint trauma and certain metabolic conditions may be associated with the development of pseudogout.
For example,hemochromatosisandhyperparathyroidismmay be associated with the disease, as are some rare genetic disorders.
Patients may also have more general symptoms like fever or malaise.
An acute gout flare-up usually involves one joint and is characterized by intense pain, redness, and swelling.
Some patients may experience flare-ups that affect multiple joints.
Eventually, attacks may occur more often, last longer, and do not resolve completely between episodes.
This may lead to chronic gout disease, which can cause long-term joint damage.
Tophaceous gout happens when solid collections of uric acid form in soft tissues, causing inflammation and tissue damage.
These collections, or tophi, may occuraround joints, in tendons, or inbursae.
They may also occur in the ears or other soft tissues.
Chronically elevated levels of uric acid may also affect the kidneys.
Pseudogout
CPPD disease can also vary widely in its presentation.
Patients may be asymptomatic.
Symptomatic patients may have acute or chronic disease.
CPPD disease attacks larger joints more commonly than gout.
Acute CPPD disease attacks may affect one or several joints.
Joint injury, surgery, or severe illness may precede an attack.
Patients commonly experience pain, redness, warmth, and decreased function of the affected joint.
The illness usually goes away on its own, though it may take days or weeks to do so.
Chronic CPPD disease may mimic other forms of arthritis.
Symptoms may coexist with those of degenerativeosteoarthritis, which causes progressive joint degeneration.
Yourbloodmay be checked to determine if you havehigh levels of uric acid.
The joint fluid is examined under polarized light microscopy.
Under polarized light, gout crystals appear needle-shaped and yellow, a property called negative birefringence.
Patients with uric acid kidney stones may present with symptoms such as flank pain or blood in the urine.
The best way to do this is to analyze stones that have already been passed.
Tests of urine uric acid levels and acidity (pH) may be evaluated to further guide treatment.
Like gout, the diagnosis of CPPD disease ultimately rests on the identification of CPPD crystals in joint fluid.
Under polarized light microscopy, CPPD crystals appear blue, a property called positive birefringence.
This distinguishes them from the negatively birefringent crystals of gout.
SPECT CT and musculoskeletal ultrasound are also used.
CPPD disease is more common in patients over 65, and may mimic osteoarthritis or rheumatoid arthritis.
Treatment
The treatment of acute gout focuses on reducing pain and inflammation.
This can be achieved withnonsteroidal anti-inflammatory agents(NSAIDs),steroid medications, orcolchicine.
Treatment should be started within 24 hours of the onset of symptoms.
In chronic gout, treatment focuses on lowering uric acid levels to prevent acute attacks.
For that reason, these drugs are not started during an acute flare.
Anti-inflammatory medications may be given when starting uric acid-lowering therapy.
Once started, therapy with uric acid-lowering medications is usually lifelong, so adhering to the medications is important.
The treatment of pseudogout aims mostly to relieve symptoms.
Patients with frequent CPPD attacks may be prescribed low-dose colchicine to reduce the number of episodes.
A Word From Verywell
Crystal-induced arthropathies like gout and CPPD disease can be painful and debilitating.
Fortunately, a variety of treatment options exist, and the diseases can usually be managed effectively with medications.
Talk to your healthcare provider about the treatment strategy that makes the most sense for you.
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