Spot Diagnosis

An 8-month-old infant presents to the pediatric dermatology clinic with his mother for the evaluation of dry scaly skin that has been unresponsive to topical emollients.

A 13-week-old boy presents to the pediatric dermatology clinic for the evaluation of a dark lesion on his back, present since birth.

A 41-year-old man presents to the dermatology clinic for the evaluation of dark linear lesions on his back. He has a medical history of chronic kidney disease (stage II), alcohol dependency and Hodgkin’s lymphoma, for which he is currently undergoing treatment.

A 71-year-old woman presents to the emergency room with fever, malaise and a peeling rash. She has a history notable for poorly controlled diabetes mellitus and had started a course of sulfamethoxazole–trimethoprim and ciprofloxacin for cellulitis of the right foot 8 days ago.

A 75-year-old man with a history of chronic obstructive pulmonary disease (COPD) and colon cancer presents with a 3-day history of an intensely pruritic and painful rash on his left mid-back.

A 58-year-old African American man presents as a referral for the evaluation of a patchy, erythematous, pruritic rash that is primarily on his trunk and legs.

A 64-year-old Caucasian woman with a history of hypertension, rheumatoid arthritis and poorly controlled type II diabetes mellitus presents for evaluation of colour changes on her left foot.

A 3-year-old boy presented to the clinic with a dark spot in his hair that measured 3 cm by 3 cm. The skin in this region was lightly pigmented, with dark hairs; the lesion had been more pigmented at birth.

A 58-year-old healthy man was evaluated for a toothache of 2 days' duration. He was treated with oral penicillin and an opiate analgesic and advised to have the affected teeth pulled.

What is the diagnosis based on this image ?