Chalky urate in a patient with bullous tophi
Authors: Hsi Yen, Hsing‐Jou Su and Wei‐Ti Chen
Published online: 6 September 2021
An 86-year-old man presented with multiple, asymptomatic tense, white bullae over bilateral toes one week after a resolved episode of acute gouty arthritis
An 86‐year‐old man presented with multiple, asymptomatic tense, white bullae over bilateral toes (Figure, A) one week after a resolved episode of acute gouty arthritis. White, chalk‐like material expressed from the bullae demonstrated monosodium urate crystals that exhibited strong negative birefringence by light microscopy (Figure, B; the white arrow shows the axis of the red compensator). Bullous tophi are an unusual presentation of gout. As patients can be asymptomatic with normal serum urate concentrations, diagnosis is aided by identifying monosodium urate crystals from chalky urate.1 Manual compression was done to drain the bullae after making a superficial needle puncture, and urate‐lowering therapy prevented recurrence.

Competing interests
No relevant disclosures.
References
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