In a patient with gouty arthritis, synovial fluid aspiration will show –
**Core Concept**
Gouty arthritis is a form of inflammatory arthritis characterized by the deposition of monosodium urate crystals within the synovial fluid of joints. This condition is caused by hyperuricemia, which can result from increased production of uric acid, decreased excretion, or a combination of both.
**Why the Correct Answer is Right**
Synovial fluid aspiration in a patient with gouty arthritis will typically reveal the presence of needle-shaped, negatively birefringent monosodium urate crystals under polarized light microscopy. These crystals are the hallmark of gout and are formed when uric acid supersaturates the synovial fluid. The presence of these crystals triggers an intense inflammatory response, leading to the characteristic pain, swelling, and redness associated with gouty arthritis.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the presence of calcium pyrophosphate dihydrate (CPPD) crystals, not monosodium urate crystals, is characteristic of pseudogout, another type of inflammatory arthritis.
**Option B:** This option is incorrect because the presence of glucose crystals is not a feature of gouty arthritis. The synovial fluid in gouty arthritis may show elevated levels of glucose due to the inflammatory response, but glucose crystals are not a diagnostic feature.
**Option C:** This option is incorrect because the presence of calcium crystals is characteristic of calcific tendinitis, not gouty arthritis.
**Option D:** This option is incorrect because the presence of lipid crystals is not a feature of gouty arthritis. Lipid crystals can be seen in conditions such as pseudogout or calcific tendinitis.
**Clinical Pearl / High-Yield Fact**
The presence of monosodium urate crystals in the synovial fluid is a diagnostic hallmark of gouty arthritis. A mnemonic to remember the characteristics of gout is "CRUSH": Crystal deposition, Redness, Swelling, Heat, and Joint pain.
**Correct Answer: C. Monosodium urate crystals.**