Introduction 10 13 1 10 10 13 23 Fig. 1 ALA: δ-aminolevulinic acid  10 20 10 4 10 13 14 4 11 13 23 Here, we describe a girl with EPP with an unusual clinical course, demonstrating that parents and physicians cannot always recognize how much the patients suffer. Case report An otherwise healthy, 4-year-old Dutch Caucasian girl presented with a 1-year history of suddenly occurring severe itching and pain in the hands, feet, and nose after sunlight exposure. These sensations lasted up to 3 days, and she reported on three such incidents during the last 12 months. The symptoms developed either immediately or up to 8 h after UV exposure. Erythema or other skin manifestations were not seen. The condition worsened in the summer months and during vacations in sunny climates. Itching commenced immediately after sunlight exposure and reached a maximum at night. After a few hours, the itching changed into pain. Application of wet towels or cold baths led to partial relief, and the symptoms usually vanished spontaneously after a couple of cloudy days without intense UV exposure. Looking back, her parents also remembered that at the age of 1 year, during a summer vacation, she had suffered from an unexplained acute swelling of the hands and feet. At that time no specific diagnosis was made, besides the suspicion of an allergy. During that vacation at the sea side, the overall family life was disturbed because she was continuously agitated, cried a lot without an apparent reason, and did not sleep well. Upon physical examination in our outpatient clinic at the age of 4, she showed no skin symptoms except for few minimal excoriations on the dorsal aspects of the feet. The family history revealed eczema in the mother and atopy in the paternal grandmother, but was unremarkable regarding increased photosensitivity. Eventually, a pediatrician suggested the differential diagnoses polymorphic light eruption, warmth intolerance, or hypochondria, and the girl was treated unsuccessfully with antihistamines. Due to continuation of her complaints, a pediatric dermatologist was consulted who suspected EPP despite the absence of cutaneous manifestations. Blood porphyrin analysis revealed elevated free erythrocyte protoporphyrin (FEP) levels of 9,821 μg/l (normal 0–300 μg/l), confirming the diagnosis of EPP. Affirmative phototesting showed maximal cutaneous sensitivity at a wavelength of 400 nm (violet light). Full blood count and liver enzymes were normal. Therapeutically, strict UV light avoidance, protective sunscreens, and annual follow-up visits were advised. Still, her photosensitivity did not improve, and mild hyperpigmentation and sores at her nose and upper lip as well as pronounced knuckles and progressive lichenification developed at the age of 6. To date, she has not shown liver enzyme alterations. Discussion Here we present a girl with EPP who suffered from a significant decrease of quality of life due to severe itching and pain of the skin. Clinically, EPP is characterized by cutaneous photosensitivity manifesting early in life. Acute photosensitivity episodes include burning, stinging, and pruritus in sun-exposed skin, particularly on the nose, cheeks, and dorsal aspects of the hands, followed by erythema, edema, and wax-like scarring. Skin symptoms can occur within minutes of sun exposure, often starting early in spring time, continuing through the summer, and diminishing in fall and winter. 1 2 11 15 19 21 23 30 31 22 23 2 22 12 28 22 3 7 13 17 25 15 18 28 15 23 Another diagnostic modality includes fluorescence microscopy of erythrocytes  2 17 5 21 24 26 27 29 2 22 13 18 23 6 13 13 28 FECH 31 32 FECH 13 28 FECH FECH 8 9 13 2 28 13 14 18 28 FECH 16 In conclusion, the diagnosis of EPP is often delayed or missed. Therefore, EPP should always be considered in photosensitive children, especially when the subjective discomfort is disproportionate to the extent of visible skin manifestations because we obviously do not always see what these patients feel. If cutaneous symptoms are completely absent, an accurate diagnosis is difficult and requires all diagnostic abilities of the attending physicians.