Which class of porphyrias is typically associated with photosensitivity?

• A. Neurologic
• B. Cutaneous
• C. Erythropoietic
• D. Hepatic

Answer: (B)

Photosensitivity from porphyrias happens when porphyrin compounds build up in the skin and absorb light, causing skin damage in sun-exposed areas. The group most characteristically linked to this issue is the cutaneous porphyrias, which present with light-induced skin fragility, blistering, and discoloration (porphyria cutanea tarda being a classic example). Other porphyrias are categorized by where the excess heme precursors originate—hepatic porphyrias tend to present with neurovisceral symptoms, while erythropoietic porphyrias arise from the erythroid lineage and can have systemic features; though some erythropoietic forms can cause photosensitivity, the defining association with skin-light sensitivity points to the cutaneous class.