[Isolated cutaneous pigmentation: adrenal insufficiency may be the cause].

INTRODUCTION

Addison's disease is a primary global deficiency in adrenocortical hormones resulting from the progressive total destruction of the adrenal glands.

CASE: A 15-year-old girl consulted after four months of pigmentation on sun-exposed areas, with photosensitivity. She reported no weakness, no decline in her general status, and no menstrual disorders. Cutaneous examination showed diffuse pigmentation of the face, the dorsal hands, the feet and palmar folds. Pigmented macules were also seen on the palms, soles, tongue and cheek mucosa. Blood and urinary electrolyte levels were within normal ranges. Plasma cortisol was low, plasma ACTH high, and the synacthen test negative. These findings led us to diagnose Addison's disease. Antithyroid antibodies were noted without antinuclear factors or antiadrenal antibodies. The patient was treated with hydrocortisone, 40 mg daily. Outcome was favorable.

DISCUSSION: Because of the presence of isolated melanoderma of the sun-exposed areas and macular pigmentation of oral mucosa in this patient, we tested for Addison's disease: hormonal testing confirmed the diagnosis. Because our patient had no electrolyte disorders, Addison's disease might have remained unknown until the onset of acute adrenal insufficiency. Etiology in this case was probably autoimmune. In the case of persistent pigmentation of sun-exposed areas, even isolated, Addison's disease must be considered and hormonal testing performed to avoid acute adrenal insufficiency.