CASE REPORT
An eight year-old Hispanic female with a history of pre-B cell acute lymphoblastic leukemia presented to our clinic due to excessive hair on her face and arms for 16 months (Figure 1). Her family believed this started one month after she completed chemotherapy treatments. She had been previously treated with vincristine, 6-mercaptopurine, methotrexate, doxorubicin, PEG asparaginase, cyclophosphamide, thioguanine, and cytarabine. She denied any other symptoms, including abdominal pain. Previous work-up for hypertrichosis revealed normal serum levels of androstenedione, testosterone, and insulin-like growth factor 1. Her past medical history was also significant for asthma for which she was treated with fluticasone (44mcg) inhaler two puffs twice daily, albuterol (2.5 mg/3mL) inhaler 1 unit dose every 6 hours as needed, and montelukast 5 mg by mouth every night.
Physical examination revealed hypertrichosis of the patient’s forehead, upper cheeks, and arms. Also noted were erosions, crusts, scarred papules, and milia on the dorsal surfaces of her hands (Figure 2). An in-office urine sample exhibited fluorescence when viewed using a Wood’s lamp (Figure 3). PCT was suspected based on the constellation of her clinical findings, as well as her urine sample. This suspicion was confirmed by a 24-hour urine sample that showed grossly elevated uroporphyrins (5039.4 mcg/24h) and heptacarboxyporphyrins (1550.2 mcg/24h). In addition, pentacarboxyporphyrin (67.0 mcg/24h) and hexacarboxyporphyrin (7.6 mcg/24h) were elevated. Other potential causes of hypertrichosis were ruled out with normal serum levels of 17-hydroxyprogesterone (17 ng/dl) and DHEA sulfate (<15mcg/dl). There was no known family history of PCT. Baseline labs revealed hemoglobin of 13.7g/dL, hematocrit of 40.7%, platelets of 134,000/u, and elevated ferritin at 1331 ng/mL. We recommended phlebotomy treatment for this patient, with goal hemoglobin between 10-11 g/dL.
DISCUSSION
PCT results from decreased activity of UROD in the heme biosynthetic pathway, leading to an accumulation of porphyrins, specifically uroporphyrinogen and heptacarboxyporphyrin. The most common clinical findings are skin fragility, bullae, erosions, and milia on the dorsal surface of the hands, feet, or face. These skin changes result from a photosensitivity reaction in which long-wave UV light excites the excess porphyrins in the skin, releasing oxygen radicals and leading to tissue damage.7 Hypertrichosis of the face is also a common finding associated with this disorder.8 PCT usually occurs in adults and is most commonly associated with ethanol use, hepatitis C, or elevated estrogen levels8. There is also a familial form of the disorder caused by a UROD mutation, which is present in about 25% of PCT patients.9 Even with a UROD mutation, symptoms do not manifest until UROD activity is less than 20%, such as when the mutation is combined with one of the known susceptibility factors.10 UROD inhibition is thought to be caused by uroporphomethene, which is created by iron-dependent oxidation.10 There have been oc-
