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subsequent degranulation of mast cells with release of histamine and other
mediators.
When large amounts of these mediators are released, generalized flushing,
persistent diarrhea, or hypotension may ensue. Children with these symptoms
require therapy directed against histamine and prostaglandin D2 . Long-acting H1
blockers like cetirizine are often combined with long-acting H2 blockers like
ranitidine. Shorter-acting H1 blockers, such as diphenhydramine and hydroxyzine,
are sometimes used as rescue agents. Caution needs to be used with medications
that potentially degranulate mast cells, such as opioids, NSAIDs and anesthetics,
as well as avoidance of physical stimuli. Children who suffer from persistent
histamine-induced diarrhea may benefit from the addition of oral cromolyn
sodium. Over time, the condition can improve although it may not completely
resolve before adolescence.
Hypopigmentation/Depigmentation
In the neonatal period, skin findings characterized but loss of pigment are most
likely related to pigment patterning in development. Pigmentary mosaicism exists
when an individual is composed of two or more genetically different cell
populations that lead to color variation. With pigmentary mosaicism, both hypoand hyperpigmentation can occur within a Blaschkoid distribution. While small
areas require reassurance, larger areas can be associated with neurologic, eye,
cardiac, and skeletal anomalies. No definitive therapy exists.


FIGURE 69.16 Infant with urticaria pigmentosa and positive Darier sign.

Partial albinism occurs when localized areas of skin and hair are devoid of
pigment. Ocular albinism is also seen. Two syndromes with albinism are
Waardenburg syndrome (white forelock, heterochromia of the iris, and
sensorineural hearing loss) and Chediak–Higashi syndrome (immunodeficiency
and leukocytes with giant granules).

Loss of pigmentation can be a result of the absence of melanocytes as in
vitiligo and halo nevi. Vitiligo is a symmetric, patchy loss of pigmentation with a
likely autoimmune etiology. Hairs located in areas of vitiligo are often white.
Vitiligo can be associated with alopecia areata, pernicious anemia, Addison
disease, hypothyroidism, diabetes mellitus, hypoparathyroidism, and other
endocrine disorders.
Suppression of melanocytic pigment production can cause loss of
pigmentation, as in postinflammatory hypopigmentation. An example of this
condition is the white patch of hypopigmentation and scaling often seen on the
face, trunk, or extremities of children with atopic eczema. The ash-leaf macule is
a flat, hypopigmented (whitish) spot that is present in more than 90% of patients
with tuberous sclerosis.
Hyperpigmentation
In the neonatal period, hyperpigmented birth marks are relatively common.
Pigment deep in the dermis appears gray or blue at the surface of the skin.
Mongolian blue spots, now called dermal melanocytosis, are an example of this
phenomenon ( Fig. 69.17 ). The Nevus of Ota is dermal pigment in the
distribution of the ophthalmic branch of the fifth nerve; this pigmentation can also
involve the sclera and palate. Patients with Nevus of Ota have a risk of glaucoma.


FIGURE 69.17 Dark blue patches on the buttocks and back of infant with dermal
melanocytosis, formerly called Mongolian spots.

Additionally, certain syndromes such neurofibromatosis, are associated with
early-onset pigmented skin lesions. Patients with this disease can initially present
with café-au-lait spots, which are flat, nonpalpable, coffee-colored lesions of
varying size and shape. When six or more lesions are present, greater than 0.5 cm
in size, neurofibromatosis should be considered. The Peutz–Jeghers syndrome is a
dominantly inherited condition that includes freckle-like lesions of the lips, nose,

buccal mucosa, fingertips, and subungual areas associated with polyps in the
small intestine, stomach, or colon. Melena and intussusception are the chief
complications that may develop, usually in the second decade of life. McCune–