Congenital triangular alopecia is a patch of hair loss in the
temple area of the scalp found mainly in very young children
from birth up to 5 years of age. The affected area is probably
present from birth, but because hair growth can be sparse in
can be some months or even years before it becomes significantly
noticeable. The affected area is often roughly triangular shaped
but may be oval in some individuals. The affected skin contains
mostly vellus hair follicles or no hair follicles at all.
The cause of congenital triangular alopecia is not known, but
its presence is not usually associated with any adverse disease
Affected individuals are typically entirely healthy. The suggested
frequency for this condition in the general population is around
0.11% (Garciahernandez 1995). The hair loss is non-progressive
and does not expand beyond these areas. It is a non-inflammatory,
form of hair loss easily confused with alopecia areata. In one
report the condition was incorrectly believed by the parents
to be induced
by doctors inserting intravenous cannulas into scalp vessels during
the neonatal period (Armstrong 1996). The condition is permanent
and the affected skin does not change later in life.
no treatment other than to graft hair follicles to the affected
if the affected area is small in size, the affected patch of skin can be surgically
removed and the edges sown together.
triangular alopecia references
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