Androgenetic Alopecia Not Uncommon in Children, Teens
June 2011
Androgenetic alopecia is fairly common in the pediatric population,
and in adolescent girls it should prompt an evaluation for
hyperandrogenism, according to Dr. Seth J. Orlow.
Androgenetic alopecia is a presenting symptom of polycystic ovary
syndrome (PCOS) in a considerable number of cases, he said at the
annual meeting of the Florida Society for Dermatology and
Dermatologic Surgery. "I think this is a place where we can really
make a difference as dermatologists," said Dr. Orlow, chair of
dermatology and professor of pediatric dermatology, cell biology,
and pediatrics at New York University.
One of the most useful laboratory tests in adolescent girls
presenting with early androgenetic alopecia is free and total
testosterone, which at elevated levels can serve as a marker for
PCOS.
"In a girl who presents with early-onset androgenetic alopecia,
think about early presentation of PCOS. Its definitely worth it to
test them," he said.
A chart review of 438 consecutive pediatric patients with alopecia
seen by Dr. Orlow and his colleagues over a 12-year period
underscored the importance of looking for this diagnosis, and
illustrated other characteristics of androgenetic alopecia in both
girls and boys. The study showed that androgenetic alopecia was the
second most common type of alopecia (after alopecia areata, which
accounted for 55% of cases), involving 13% of the cases overall.
Among the 123 adolescent patients, however, 42% (52 patients: 36
boys and 16 girls) had androgenetic alopecia, for a total of 38 boys
and 19 girls with androgenetic alopecia among the 438 studied.
Female Findings
Of the 19 girls, 9 had hyperandrogenism. Three had clinical signs
and 6 had biochemical signs of hyperandrogenism. Of the six with
biochemical signs, three had elevated free and total testosterone
levels, one had elevated free and total testosterone and elevated
dihydroepiandrosterone sulfate, one had an elevated free
testosterone level only, and one had an elevated total testosterone
level only
Seven of the girls were oligomenorrheic, and two were premenarchal.
Clinical signs other than the androgenetic alopecia included
hirsutism in four girls, acne in six, and seborrheic dermatitis in
two.
Other laboratory findings in the 19 girls with androgenetic alopecia
included antithyroid antibodies in 1of 5 tested and low serum iron
in 3 of 14 tested. None of the girls tested had abnormal thyroid
function, iron deficiency anemia, or low testosterone levels, Dr.
Orlow said.
The most common presentations in girls were diffuse scalp thinning
and thinning at the crown, each occurring in 8 of the 19 patients.
The remaining three girls presented with frontal thinning only.
Male Findings
Findings in the boys presenting with androgenetic alopecia included
antithyroid antibodies in 1 of 7 tested, hyperandrogenemia in 2 of
14 tested, and low testosterone levels in 3 of 14 tested. None of
the boys had abnormal thyroid function, low serum iron, or iron
deficiency anemia.
A disproportionate number of boys (13 of the 38) presented with
classic female pattern androgenetic alopecia with diffuse thinning
of the crown. The remaining boys presented with bitemporal vertex
thinning (18 boys), vertex only thinning (4 boys), or frontal and
vertex thinning (3 boys), Dr. Orlow said.
Concomitant findings included acne in 32% of the girls and 50% of
the boys, and seborrheic dermatitis in 37% of the girls and 16% of
the boys. A family history of androgenetic alopecia was present in
both, with 82% of the boys and 87% of the girls having an affected
first- or second-degree relative.
Differential Diagnoses
It is important to consider possible differential diagnoses in
patients presenting with what appears to be androgenetic alopecia,
Dr. Orlow said.
These include acute telogen effluvium, chronic telogen effluvium
(particularly in girls), and diffuse alopecia areata.
If the clinical diagnosis is unclear in boys with female pattern
hair loss, in girls with very young onset, or if the patient or
parents have a great deal of anxiety about the diagnosis a biopsy
may be helpful, he said.
Of the 57 patients with androgenetic alopecia included in his chart
review, 14 (5 girls and 9 boys) underwent biopsy; all of the
biopsies showed typical features of androgenetic alopecia, including
increased vellus/telogen hairs and connective tissue
streamers/follicular stelae below small vellus follicles.
Eight of the 14 also had varying degrees of peri-infundibular
lymphocytic inflammatory infiltrate and fibrosis.
Treatment
Treatment options for patients with androgenetic alopecia include
minoxidil, finasteride (in boys), and spironolactone.
Minoxidil was used in 16 of the 19 girls; 4 of 6 with greater than 6
months of follow-up had stabilized at 1 year. One developed
increased facial hair on treatment, which resolved with a switch
from a 5% to a 2% formulation, Dr. Orlow said.
Two patients discontinued treatment because of a lack of efficacy
and/or headache and nausea.
In the boys, 36 of the 38 were treated with minoxidil, and 18 of 23
with at least 6 months of follow-up were stabilized. Two patients
never started treatment and two discontinued for lack of efficacy
and acne.
Finasteride was used in nine boys, including seven who also received
minoxidil. In six boys, with at least 6 months of follow-up, all had
better hair density (including four on concomitant minoxidil). One
experienced sexual dysfunction, which resolved spontaneously, Dr.
Orlow said.
"I did not treat and would not treat girls [with finasteride], nor
did I find any case reports of finasteride use in girls," he said.
There are a few case reports, however, of spironolactone being used
in girls with some success, he noted.
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