Discoloration of nail plates. Many chemicals can discolor nail plates. Solutions of potassium permanganate and silver nitrate stain nail plates brown-purple and jet black, respectively. In the case illustrated here, the stain derived from resorcinol. Such stains are harmless and can be easily removed by superficial scaling with the edge of a glass slide.
Fordyce’s condition. The face abounds in sebaceous glands. Normally their distribution stops sharply at the junction of the skin and vermilion of the lips. Commonly, however, ectopic sebaceous glands are found within the lips under the vermilion and sometimes within the oral mucosa of the lips and even in the buccal mucosa. The condition is harmless and may have been present long before the patient or parents became aware of it. No treatment is required or available.
Thrush is an infection of the mouth caused by the candida fungus, also known as yeast. Candida infection is not limited to the mouth; it can occur in other parts of the body as well, causing diaper rash in infants or vaginal yeast infections in women.
Dermatofibroma. These are benign dermal nodules that represent a focal proliferation of fibroblasts; the overlying epidermis is slightly thickened. Their occurrence is not unusual in children and adolescents. Dermatofibromas are firm and may be black, red, brown, or flesh-colored. Their diameter generally ranges from 0.5 to l.5 cm, although they may occasionally be larger. Dermatofibromas may be solitary or multiple, and they develop either spontaneously or after minor trauma to the skin, such as an insect bite. Most are asymptomatic but sometimes may be painful on palpation. A very useful diagnostic maneuver is executed by exerting lateral pressure on the lesion. The skin overlying a dermatofibroma will frequently dimple. Dermatofibromas require surgical treatment only when they are of cosmetic concern to the patient. However, biopsy analysis is occasionally required in order to confirm the diagnosis and to differentiate it from more serious disorders.