Eating disorders are significant causes of morbidity and mortality in adolescent females and young women. They are associated with severe medical and psychological consequences, including death, osteoporosis, growth delay and developmental delay. Dermatologic symptoms are almost always detectable in patients with severe anorexia nervosa (AN) and bulimia nervosa (BN), and awareness of these may help in the early diagnosis of hidden AN or BN. Cutaneous manifestations are the expression of the medical consequences of starvation, vomiting, abuse of drugs (such as laxatives and diuretics), and of psychiatric morbidity. These manifestations include xerosis, lanugo-like body hair, telogen effluvium, carotenoderma, acne, hyperpigmentation, seborrheic dermatitis, acrocyanosis, perniosis, petechiae, livedo reticularis, interdigital intertrigo, paronychia, generalized pruritus, acquired striae distensae, slower wound healing, prurigo pigmentosa, edema, linear erythema craquelé, acral coldness, pellagra, scurvy, and acrodermatitis enteropathica. The most characteristic cutaneous sign of vomiting is Russell’s sign (knuckle calluses). Symptoms arising from laxative or diuretic abuse include adverse reactions to drugs. Symptoms arising from psychiatric morbidity (artefacta) include the consequences of self-induced trauma.
The role of the dermatologist in the management of eating disorders is to make an early diagnosis of the ‘hidden’ signs of these disorders in patients who tend to minimize or deny their disorder, and to avoid over-treatment of conditions which are overemphasized by patients’ distorted perception of skin appearance. Even though skin signs of eating disorders improve with weight gain, the dermatologist will be asked to treat the dermatological conditions mentioned above. Xerosis improves with moisturizing ointments and humidification of the environment. Acne may be treated with topical benzoyl peroxide, antibacterials or azaleic acid; these agents may be administered as monotherapy or in combinations. Combination antibacterials, such as erythromycin with zinc, are also recommended because of the possibility of zinc deficiency in patients with eating disorders. The antiandrogen cyproterone acetate combined with 35μg ethinyl estradiol may improve acne in women with AN and should be given for 2–4 months. Cheilitis, angular stomatitis, and nail fragility appear to respond to topical tocopherol (vitamin E). Russell’s sign may decrease in size following applications of ointments that contain urea. Regular dental treatment is required to avoid tooth loss.