EPP Case 1: A Teenager with Recurrent Light-Induced Pain and Swelling

"EPP Case 1: A Teenager with Recurrent Light-Induced Pain and Swelling" opens the first of two patient cases, presented by Dr. Bonkovsky.

Dr. Bonkovsky presents a 15-year-old girl who comes to dermatology with her mother after eight years of recurrent light-induced pain and swelling of the hands and face. Symptoms began around age 7 as mild burning after brief outdoor play in Seattle and worsened after the family moved to Phoenix. At age 12 her pediatrician diagnosed a sunscreen allergy and eczema and prescribed SPF 100 sunscreen, antihistamines, and topical corticosteroids. None of them helped, and after a soccer tournament last month she was treated for sunburn at urgent care. Episodes begin with burning and tingling within 10 to 15 minutes of sun or intense visible light, and redness and swelling resolve over 24 to 48 hours, generally without blistering. Her examination is normal.

Dr. Bonkovsky calls this a very typical presentation and contrasts it with porphyria cutanea tarda, congenital erythropoietic porphyria, and hepatoerythropoietic porphyria. Those conditions cause prominent bullae, slowly healing and often infected lesions, and sclerodermatous change, and patients often do not link the rash to sunlight because it is not immediate. In EPP or XLP he expects, at most, lichenification over the knuckles and mild fissuring around the mouth.

The patient misses two to three school days a month, has left her travel soccer team, and feels isolated, and her younger brother has similar unevaluated sun sensitivity. Dr. Bonkovsky's priority is a firm diagnosis with genetic testing to distinguish classical EPP from XLP. He would then test the brother and other first-degree relatives using whole blood protoporphyrin at Mayo and targeted mutation analysis. He would also assess liver status and vitamin D levels.

Up next, in "Recognizing EPP: Diagnostic Red Flags, Psychosocial Burden, and Confirmatory Workup," Dr. Bonkovsky examines the missed clues, the psychosocial toll on the patient, and her confirmatory workup.