Not Your Ordinary Rash.

Abstract

A 17-year-old, 6-week pregnant female presented to the emergency department with symptoms of abdominal pain, nausea, and vomiting for 2 days. Although she initially complained of only low right abdominal pain, by the next day, she complained of a generalized abdominal ache. Laboratory values upon admission included a plasma sodium concentration of 118 mmol/L, potassium of 3.0 mmol/L, and chloride of 80 mmol/L. On the third day of admission, she experienced 2 seizures. She denied previous history of seizures or other neurological diseases, but she did have a long history of “eczema-like” rashes on her face, neck, and hands that had been unresponsive to prednisone. A urine drug screen was negative, and physical examination was unremarkable. On review of her chart, it was noted that 6 months before her hospital admission, the patient had consulted a dermatologist who described numerous small eroded papules and scarring on the back of the patient s hands, neck, and upper chest. Urine and plasma specimens collected during this dermatology appointment had been sent to a reference laboratory for porphyrin fractionation and porphobilinogen (PBG)3 measurement. Results are presented in Table 1. Because of the patient s symptoms upon presentation to the emergency department and previously increased urine PBG concentration, she was treated with daily hemin infusions for 4 days and her symptoms resolved. Over the consequent 2 days, her plasma sodium concentration increased to 135 mmol/L and she was discharged.\n\nView this table:\n\nTable 1. \nPlasma porphyrin fractionation, urine PBG, and urine porphyrin fractionation results.\n\n\n\n### DEFECTIVE HEME SYNTHESIS\n\nThe porphyrias are a group of metabolic disorders caused by functional alterations in the enzymes responsible for heme synthesis, resulting in the accumulation of heme precursors. Porphyrias are categorized as either acute or cutaneous, and presenting symptoms are defined by the enzymatic defect and the properties of the accumulated heme intermediate (1). (Fig. 1) These …