What is the crystal shape characteristic of pseudogout?

The correct answer is rhomboid/rod-shaped crystals, which are characteristic of pseudogout. Pseudogout, also known as calcium pyrophosphate dihydrate (CPPD) crystal deposition disease, involves the deposition of CPPD crystals in the joints and is often associated with osteoarthritis. The rhomboid shape of these crystals is distinct and helps differentiate pseudogout from gout, which involves needle-shaped monosodium urate crystals resulting from uric acid deposition.

The identification of these rhomboid-shaped crystals through polarized light microscopy is crucial for accurate diagnosis and management of the condition. This characteristic crystal shape reflects the underlying biochemical and structural differences in the crystal types involved in different types of arthritic conditions. Recognizing the rhomboid/rod shape is essential for clinicians when performing joint aspiration and analyzing synovial fluid in patients with joint pain, leading to appropriate treatment strategies.