What kind of crystals are typically found in gout?

Gout is characterized by the presence of monosodium urate crystals, which are derived from the precipitation of uric acid in joint fluids. The important diagnostic feature of these crystals is that they are negatively birefringent when viewed under polarized light microscopy. This means that when the crystals are oriented in a specific way, they will exhibit distinct colors against the background, which can assist clinicians in diagnosing gout effectively.

In contrast, positively birefringent rhomboid crystals are associated with conditions like pseudogout, which is caused by calcium pyrophosphate dihydrate deposits. Calcium oxalate crystals are linked to conditions involving kidney stones, not gout. Amorphous crystals indicate a lack of distinct crystalline structure and are typically not associated with gout.

Thus, the identification of negatively birefringent uric acid crystals is crucial in confirming a diagnosis of gout, highlighting their significance in the clinical context of joint inflammation and pain caused by the accumulation of uric acid.