A deficiency or excess of certain required vitamins or minerals can cause specific findings in the skin, hair, nails, and mucosae. This chapter provides images of many of these findings, both common and rare.
Deficiencies in some essential nutrients cause a particular constellation of mucocutaneous and systemic signs and symptoms worth outlining. These include the bleeding gums, corkscrew hairs, easy bruising. and perifollicular hemorrhages seen in the setting of vitamin C deficiency, or scurvy. In pellagra, or vitamin B 3 (niacin) deficiency, a combination of a photodistributed eruption appearing sunburn-like, scaly, hyperpigmented, or atrophic can be seen along with protracted diarrhea, weakness, dementia, paresthesias, and depression. Kwashiorkor, or protein-energy malnutrition, may present with general lightening of the skin and hair, a scaly eruption with superficial peeling of skin resembling flaking paint, and a dermatitis with cracked skin resembling “crazy pavement” in the setting of a patient with signs of edema and poor growth. These nutritional deficiencies can occur due to general malnutrition where food is scarce, but can also occur in individuals with restricted diets or eating disorders (e.g. anorexia nervosa). Lastly, malabsorption states as found in inflammatory bowel diseases can lead to nutritional deficiencies.
Another relatively common deficiency that presents most commonly during infancy is zinc deficiency leading to acrodermatitis enteropathica. In this condition, scaly and erosive patches tend to be well demarcated with heaped-up, sometimes crusted, borders that consistently affect the perioral region, distal extremities, and groin. Affected infants with acrodermatitis enteropathica are notably irritable. Acrodermatitis enteropathica–like conditions can be seen in some inherited metabolic conditions, including those leading to biotin deficiency.