Gout is a metabolic disease of hyperuricemia in which crystals of monosodium urate are deposited in tissues. When deposited cutaneously, they are called tophi. Common locations of tophi include acral joints, extensor surfaces, and the helix of the ear. Less commonly, they can involve the finger pads and nails. Gouty tophi in the nail matrix or nail bed may cause onychodystrophy including longitudinal ridging and grooves in the nail plate. Hyperkeratotic lesions mimicking squamous cell carcinomas have also been reported. It is rare for tophi to involve the nails without evidence of additional tophi in more classic locations.
ICD10CM: M10.9 – Gout, unspecified
SNOMEDCT: 90560007 – Gout
Differential Diagnosis & Pitfalls
A yellow papule of the nail apparatus may also represent:
Below is a list of drugs with literature evidence indicating an adverse association with this diagnosis. The list is continually updated through ongoing research and new medication approvals. Click on Citations to sort by number of citations or click on Medication to sort the medications alphabetically.