An unusual patient with Rothmund-Thomson syndrome, porokeratosis and bilateral iris dysgenesis.

Rothmund-Thomson syndrome (RTS) is a rare autosomal recessive genodermatosis characterized by poikiloderma and the variable presence of other features including skeletal and ocular abnormalities, ectodermal defects, and susceptibility to certain malignancies. We report a 40-year-old woman with known RTS who developed porokeratoses on her limbs in adulthood, an association that has not previously been reported. In addition, she had bilateral iris dysgenesis, which has only been described once before in RTS.