A form of progressive mucocutaneous pigmentation caused by singly dispersed melanosomes within keratinocytes.
Acquired Universal Melanosis; Progressive Black Carbon Hyperpigmentation of Infancy; Melanosis Universalis Hereditaria; Diffuse Congenital Melanosis; Progressive Hyperpigmentation.
Unknown, but no more than 10 cases have been published.
The etiology of Carbon Baby Syndrome remains to be determined, but excessive production of β-melanocytes-stimulating hormone, or increased sensitivity of melanocytes to normal or abnormal endocrine and/or neural stimuli due to a genetic defect have been discussed. Family history, laboratory workup, personal and maternal medical history, as well as exposure to drugs or toxins are typically unremarkable. Diffuse and progressive hyperpigmentation of the skin is present from early infancy on (age of 3-6 months), often starts on the limbs and face and then eventually spreads to the rest of the body within 2 to 4 years. The finger- and toenails may show black-pigmented lines along the longitudinal axis. Most patients are otherwise perfectly healthy and have no other symptoms (including the eyes), while others present with facial features that may include sparse scalp hair with decreased pigmentation, broad cheeks, a long and bulbous nose, anomalies of the external female genitalia, severe melanosis oculi of sclera and conjunctiva with normal fundus, and mental retardation. In some patients, the hyperpigmentation may be patchy, also include the oral mucosa, while the genital region, palms, and soles may be spared. The skin texture and sweat secretion are normal. Histologic examination of the skin reveals keratinocytes with free granules of melanin in their cytoplasm, orthohyperkeratosis, excessive melanin pigmentation of the epidermal basal and suprabasal layers (including stratum corneum), and the presence of melanophages in the dermis. Melanin production in the melanocytes is increased, but the number of melanocytes is usually normal. Shortening and blunting of rete ridges may be present, whereas junctional activity or nevus cells are absent. One reported patient had gray staining of his white underwear after 1 hour of wearing it.
Precautions before anesthesia
Routine preoperative assessment. Developmental delay may cause agitation and stress in the perioperative period, thus anxiolytic and sedative premedication and/or presence of a parent (or primary caregiver) for induction of anesthesia may be beneficial.
There are no anesthetic concerns specific to this disorder. In the neonate, diffuse discoloration may be caused by adrenal insufficiency and should be excluded prior to surgery or anesthesia. A transient gray-brown color can be seen following phototherapy for hyperbilirubinemia.
None specific to this disorder.
Other conditions to be considered