Prurigo pigmentosa is a rare pruritic inflammatory dermatosis with a unique staged clinicopathological presentation. It was first reported by Nagashima in 1971, and recently, more cases have been reported We introduce a case of a young Saudi female who developed biopsy proved prurigo pigmentosa after she followed strict ketogenic diet. Her condition resolved after she resumed a regular diet.

Skin metastasis commonly manifest as subcutaneous or intradermal violaceous nodules that coalesce with a firm rubbery appearance. Few cases reported an erythema ab igne-like appearance in the presence of internal malignancy. We report a case of metastatic colorectal adenocarcinoma with erythema ab igne-like presentation. We also review cases of erythema ab igne in association with internal malignancy.