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traumatized areas) ( Fig. 88.10 ). JXG lesions may also look like xanthomas.
Unlike xanthomas, however, abnormal lipid levels do not occur with JXGs.

FIGURE 88.8 Pyogenic granuloma.


FIGURE 88.9 Urticaria pigmentosa with Darier sign.

Mastocytoma, Urticaria Pigmentosa
These are red/brown papules that urticate. For additional information please see
Chapter 69 Rash: Neonatal .
Juvenile Xanthogranulomas
Juvenile xanthogranuloma. JXGs can be confused with urticaria pigmentosa or
xanthomas. Numerous yellow or reddish-brown papules appear on the face and
upper trunk in the first year of life. The number of lesions may increase until the
child is 18 months to 2 years of age. Serum lipid levels are normal, and the Darier
sign (urtication after scratching) is negative. The lesions often disappear
spontaneously after 2 years of age; therefore, intervention is generally
unnecessary. When JXGs are multiple, particularly on the head and neck,
evaluation of the eyes for intraocular JXGs is recommended because of their
potential for visual impairment. The presence of JXGs in a young child with
neurofibromatosis (type 1) has been a marker associated with an increased risk of
juvenile myelomonocytic leukemia.


FIGURE 88.10 Juvenile xanthogranuloma (JXG).

Skin-Colored Papules
Many entities may present as skin-colored papules. Here we will highlight lichen
striatus and lichen nitidus. When the papules are arranged linearly, streaming
down an extremity or across the face or neck, lichen striatus should be

considered. If the papules are not arranged linearly but are tiny pinpoint, skincolored papules, lichen nitidus should be considered, especially if a Koebner
phenomenon is present. Flat warts may be skin colored as well.
Lichen Striatus
Lichen striatus is an asymptomatic eruption of unknown cause. The flat-topped
papules are arranged linearly and may be confluent. Lesions may occur in a wide
band but remain characteristically linear or more accurately curvilinear patterns
corresponding to lines of Blaschko. The lesions are skin colored to erythematous
in Caucasians and often hypopigmented in African Americans. The eruption
follows the long axis of an extremity ( Fig. 88.11 ) or may involve any other part
of the skin surface (especially the face). Because the eruption resolves
spontaneously within 2 years, no treatment is necessary.


Lichen Nitidus
Lichen nitidus is characterized by tiny, pinpoint, flat-topped, skin-colored papules
( Fig. 88.12 ). The papules are often grouped and are found in scratch lines (i.e.,
the Koebner phenomenon). Although any skin surface may be involved, the trunk
and genitalia are common sites. The lesions are often asymptomatic but may
occasionally itch. The lesions persist for variable periods and generally do not
respond to therapy.

PLAQUES
Annular Plaques
Granuloma Annulare
Granuloma annulare is believed to be an idiosyncratic response to trauma and
looks to many like tinea corporis (“ringworm”) without the scale. This skin
change may begin as a skin-colored or violaceous papule that clears centrally as
the margins advance, or it may appear as a group of papules arranged in a ringlike configuration ( Fig. 88.13 ). The central portion of the lesion is often dusky
or hyperpigmented. The key point on physical examination is the lack of scaling.
This physical finding distinguishes granuloma annulare from tinea corporis. The

border is firm on palpation, unlike tinea corporis. The rings can be 5 cm in
diameter or larger.

FIGURE 88.11 Lichen striatus.