Version October 2024
| Sex | Age of onset | Timeline of eruption | Location | Common lesion morphology and symptoms | Family history | Action spectrum | Phototesting | Laboratory findings | Duration/ resolution | Key features | |
| Polymorphous light eruption | F>M | First 3 decades | Hours after sun exposure, lasts days to weeks; most conspicuous in spring; improves during summer | Sun-exposed areas | Pruritic papules, papulovesicles, plaques. | May be present | UVA, UVB, visible | Normal MED; provocative phototesting may induce lesions. | Recurrent over the course of years, may improve over time | Most common photodermatosis; "hardening" phenomenon may occur. | |
| Juvenile spring eruption | M>F | Primarily childhood; also may be seen in young adults | As with polymorphous light eruption | Classically, helices of ears | Erythematous papules, bullae. | May be present | UVA? | As with polymorphous light eruption. | Recurrent over years, may improve with age | ||
| Actinic prurigo | F>M, M>F reported in adult onset in Asia | Childhood; adult onset may occur in Asians | Persistent during summer; may also be present year round | Sun-exposed areas, may also affect unexposed areas | Pruritic papulonodules, crusts, excoriations, lichenification, cheilitis. | Yes, in up to 50% | UVA>UVB | 60% with reduced MED, 60 to 70% with positive provocative phototests. | Improves in adolescence, but also may persist | More common in American Indians and Mestizos. May have ocular findings. | |
| Hydroa vacciniforme | Slight M>F | Childhood | Hours after sun exposure | Face, dorsal hands | Erythematous macules, papules, vesicles, crusts. | Rarely positive | Likely UVA | May show reduced MED to UVA in some cases. | Usually resolves by adolescence/young adulthood, but may persist | Lymphoproliferative disease association with severe cases. | |
| Chronic actinic dermatitis | M>F | Older, but may be seen in younger patients | Persistent; worsens in summer, may have findings year round | Sun-exposed areas | Eczematous patches, lichenification, may see palmoplantar involvement. | UVA, UVB, visible light | Decreased MEDs to UVA, UVB, or visible light. | May see Sézary cells in severe cases | Persists for years, may resolve | Often coexistent contact dermatitis. | |
| Solar urticaria | F>M | Young or mid-adulthood | Appears within minutes, individual lesions resolve within 24 hours | Sun-exposed areas | Urticarial plaques (hives), occasional systemic symptoms. | UVA, UVB, visible light | Evaluated with MUD. | Persists for years, may resolve | "Hardening" phenomenon may occur. | ||
| Phototoxicity | M = F | Any age | Appears within hours of sun exposure, can occur after first dose of drug | Sun-exposed areas | Exacerbated sunburn appearance. | UVA | In systemic phototoxicity, MED for UVA decreased, UVB and visible light MEDs normal. | Resolves when drug discontinued and cleared from body | Can occur in anyone. | ||
| Photoallergy | M = F | Any age | Appears 1 to 2 days after exposure to sun and inciting agent in sensitized individual | Sun-exposed areas | Pruritic, eczematous lesions. | UVA | In systemic photoallergy, MED for UVA decreased, UVB and visible light MEDs normal. Occasional drugs have reduced MED to UVB rather than UVA. | Resolves with discontinuation of inciting agent | Usually due to topical agents. | ||
| Erythropoietic protoporphyria | M = F | Onset in early childhood; rarely in adults with clonal bone marrow disorders | Symptoms may begin within minutes of sun exposure; worse in spring and summer, improves in winter | Nose, cheeks, hands | Acute prodromal burning pain, itching, stinging; continued exposure followed by severe pain, swelling, systemic symptoms. Skin findings absent or mild scarring, leathery changes on knuckles or face. | Variable, autosomal recessive, often skips generations | Soret band (400 to 410 nm) | Often normal, some patients may note stinging sensation or lesions. | Markedly elevated erythrocyte protoporphyrin (approximately 85 to 100% metal-free) | Lifelong | Altered behavior and impaired quality of life. May develop liver disease, which may be severe. |
| X-linked protoporphyria | M>F | Onset in early childhood; rarely in adults with clonal marrow disorders | Symptoms may begin within minutes of sun exposure; worse in spring and summer, improves in winter | Nose, cheeks, hands | Acute prodromal burning pain, itching, stinging; continued exposure followed by severe pain, swelling, systemic symptoms. Skin findings absent or mild scarring, leathery changes on knuckles or face. | Variable, X-linked inheritance | Soret band (400 to 410 nm) | Often normal, some patients may note stinging sensation or lesions. | Markedly elevated erythrocyte protoporphyrin (approximately 50 to 85% metal-free) | Lifelong | Altered behavior and impaired quality of life. May develop liver disease, which may be severe. |
| Porphyria cutanea tarda | M>F | Middle age, may occur earlier | Lesions develop subsequent to and may seem unrelated to light exposure | Dorsal hands, face, feet and other sun-exposed areas | Chronic, mostly painless skin fragility, bullae, crusts, scarring, hypertrichosis, hyper- and hypopigmentation, sclerodermoid changes. | Uncommon; approximately 20% have heterozygous UROD mutations with low penetrance; some have HFE (hemochromatosis) mutations | Soret band (400 to 410 nm) | Elevated urine and plasma porphyrins (mostly uroporphyrin and heptacarboxyl porphyrin) | Chronic; readily treated by phlebotomy, low-dose hydroxychloroquine or antivirals for hepatitis C | Iron-related disorder with combinations of contributing factors, either acquired (alcohol, smoking, hepatitis C, estrogens) or inherited (UROD and HFE mutations). | |
| Pseudoporphyria | F>M | Any age; 10% of children taking naproxen | Sun-exposed areas | Skin fragility, bullae, crusts, scarring, milia. | Negative | UVA | Normal porphyrin levels | Symptoms resolve with sun protection, avoidance of tanning bed use, and discontinuation of the causative medications | May be caused by medications, renal failure and hemodialysis, and excessive tanning bed use. |
Do you want to add Medilib to your home screen?
