Diagnosing Foot Pain Associated With Systemic Disease
Several systemic diseases can trigger foot pain, including different types of arthritis. The most common type of arthritis in your feet is gout, or crystal-induced arthritis, if we want to include pseudogout, too. These diseases are triggered by the accumulation inside the articulation of sodium urate or calcium pyrophosphate dihydrate crystals, respectively.
In this regard, it is essential to remember your gender because gout is more common in males than women, and it is usually located in the great toe with sudden attacks of excruciating pain, swelling, and hyperreactive skin. So, if you come with these symptoms as a male, the doctor will probably think of gout as the first diagnostic suspicion and order a uric acid blood test. The diagnosis is confirmed when the joint is aspirated, and sodium urate crystals are seen under the microscope. But not all patients will go through an aspirate. A clinical suspicion and high uric acid levels in the blood are usually enough to start the treatment and give you some lifestyle measures to consider. You may also need to go through a radiograph showing periarticular erosion. In contrast, pseudogout involves the metatarsophalangeal joint and looks like a degenerative joint disease in the radiograph.
Other types of arthritis should be ruled out, including rheumatoid arthritis and seronegative variants of arthritis. Rheumatoid arthritis is diagnosed by evaluating the pattern of the disease. When one foot is affected, the other should also be affected to suspect arthritis. It is a symmetric pattern in most cases and is three times more likely in women than men. The onset of the disease is usually not a sudden problem that will take you to the emergency room. Thus, rheumatoid arthritis is more likely a diagnosis you will get in a scheduled visit to a rheumatologist.