A two-years-old boy presented with abnormal body
pigmentation and body asymmetry noted since birth. A
preceding vesicular eruption was absent. He was
developmentally normal. Family history was insignificant.
Examination revealed linear and whorled hyperpigmented
macules in a reticulate pattern along the Blaschko’s lines
over trunk and limbs with sparing of palms, soles and mucous
membranes (Fig. 1), suggestive of Linear and
Whorled Nevoid Hypermelanosis (LWNH). There was left-sided
hemi-atrophy. Systemic examination was unremarkable.
Fundoscopy was normal. Skin punch biopsy revealed increased
pigmentation of the basal layer without incontinence of the
pigment. Karyotype, echocardiography and MRI brain were
normal.
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Fig. 1 Linear and Whorled
Nevoid Hypermelanosis: Linear and whorled
hyperpigmented macules in a reticulate pattern along
the Blaschko’s lines over trunk and limbs.
|
LWNH is a rare disorder and may be
associated with developmental delay, autism, seizures,
ocular, cardiac and skeletal abnormalities. Hemi-atrophy has
been reported only rarely. It needs to be differentiated
from other linear pigmentary disorders distributed along the
Blaschko lines. Incontinentia pigmenti is an X-linked
dominant disorder presenting in females with a vesicular
phase preceding the pigmentary phase. Linear epidermal nevus
has characteristic hyperkeratotic plaques. Hypomelanosis of
Ito and segmental nevus depigmentosus present with
hypopigmented lesions.
