Volume 214 - Issue 6
Palmoplantar keratosis caused by arsenic toxicity
Authors: Kajal Patel, Alexander Gin and Laura Scardamaglia
Med J Aust 2021; 214 (6): 258-258. || doi: 10.5694/mja2.50965
Published online: 5 April 2021
Published online: 5 April 2021
A 74-year-old Vietnamese man presented with a 1-year history of pruritic nodules on his feet
A 74‐year‐old Vietnamese man presented with a 1‐year history of pruritic nodules on his feet. There was no history of gastrointestinal cancer or hereditary palmoplantar keratoderma. Examination found bilateral, focal, palmoplantar keratoses of the soles (~ 6 × 8 cm), with mild palmar involvement (~ 1 × 1.5 cm) (Figure). The differential diagnoses were psoriasis, lichen planus and verrucae vulgaris, but there were no other clinical features consistent with these conditions.
History revealed substantial ingestion of green tea imported from Japan (10 cups per day over 50 years), which was steeped continuously, allowing significant absorption into the water.
Arsenic toxicity was suspected. Elevated levels of arsenic were identified in the patient’s urine (2620 nmol/24 h; reference interval, < 470 nmol/24 h) and blood (0.294 µmol/L; reference interval, < 0.160 µmol/L). Malignancy screen and histology of the keratoses found no malignancy. The patient’s condition improved after treatment with topical emollients and cessation of green tea.
Competing interests
No relevant disclosures.