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Intralesional
corticosteroids for alopecia areata
Although research over the last few years has yielded valuable
data on the etiology and pathogenesis of the insidious form of
hair loss in alopecia areata, the answers of many unfathomable
questions remain elusive to scientists and medical experts. With
a mysterious etiology, there is neither a permanent cure for alopecia
areata nor a universally proven therapy for inducing remission.
Corticosteroids are, so far, the mainstay of treatment for patchy
alopecia areata. There is supporting evidence to substantiate
the theory that alopecia areata is a T-cell mediated response
and corticosteroids are known to exert a strong inhibitory effect
on the activation of T lymphocytes. Corticosteroids also reduce
inflammation and pain, and can be administered in four different
ways; topically as a cream or lotion, intralesional as local injections
into the bald patches, and systemically either as injections into
a muscle or taken orally. Each of these methods of administration
varies in their potency, and also bears different rates of success
and side effects.
In general, treatment of alopecia areata patients is based on
criteria like age and extent of disease, and potentially everyone
with alopecia areata is capable of re-growing hair even after
many years of hair loss. Intralesional steroids are used frequently
to treat alopecia areata, particularly localized patches, and
these injections are a very popular compromise between topical
application and systemic use.
Intralesional corticosteroid therapy implies injecting a drug
directly into the skin lesion for faster action and better results.
The concept of intralesional injection is to let the drug pass
the barrier zone and establish a sub-epidermal depot thus allowing
a higher concentration of the drug to act at the site of the disease.
However, once disease extent exceeds 50 percent of the scalp,
the use of intralesional steroid is hindered by the total amount
of drug required to cover the affected area.
Typically, the procedure involves the injection of a steroid
solution (usually triamcinolone acetonide) just below the epidermis,
using a 1-mL tuberculin syringe and a 30-gauge 1/2-inch or 1-inch
needle. Up to 0.1 mL is typically injected per site, and injections
are spread out to cover the affected areas. In effect, the cortisone
removes the confused immune cells and allows the hair to grow.
Care must be taken during the procedure, as injection just a
millimeter too deep will render the steroids much less effective.
The purpose is to get as much of the steroid directly to the root
of the affected hair follicles where the associated inflammatory
infiltrate is present, as injected into the fat, the steroid will
result in the development of atrophy and elicit an ineffective
response.
Some clinics use compressed air guns to "inject" the
steroids, which are much faster and usually less painful. Depending
on the extent of hair loss there may be a need for numerous injections
over the bald regions. It can take up to 2 months before noticeable
hair growth develops. Use of steroid injections is a popular form
of treatment for eyebrow hair loss. Interestingly, intralesional
steroids have also been used to initiate eyelash hair re-growth
in some alopecia areata patients.
It is important to note that there are significant problems in
defining and comparing the success rate of intralesional corticosteroids
with other treatment routines for alopecia areata. Many reports
on trials involve perhaps a small number of patients without any
control group for comparison. This leads to the limitation of
the inability to compare trials using different treatments. Absence
of age matched groups with alopecia areata of similar extent and
duration coupled with the different parameters individual clinicians
use to define satisfactory hair re-growth, make comparison between
different treatment types almost impossible.
In practice it is impossible to treat alopecia totalis or extensive
alopecia areata by intralesional steroid injections alone and
this line of treatment is only indicated in patchy alopecia with
long standing bald areas.
Success
rate of intralesional corticosteroids in alopecia areata treatment
Studies have been conducted comparing the use of different steroid
preparations. Commonly used preparations for intralesional use
are triamcinolone acetonide or triamcinolone hexacetonide. Five
to 10 mg/mL are typically administered to scalp lesions and 3
to 5 mg/mL to eyebrow areas. On an average, hair re-growth is
noticed at the injected site within 2 to 6 weeks of injection.
In one particular study, 84 patients with various degrees of
alopecia areata were administered injections of 0.1 mL of 5 mg/mL
of triamcinolone acetonide every 1 to 2 weeks times, using a Porto
Jet needle-less injector. 6 weeks after the procedure, 92 percent
of patients with patchy disease and 61 percent of those with alopecia
totalis showed evidence of pigmented terminal hair re-growth.
However, a substantial proportion of both groups lost this re-growth
by 12 weeks (re-growth maintained in 71 percent of patients with
alopecia areata and 28 percent of those with alopecia totalis).
This form of therapy elicited a poor response in patients with
rapidly progressive alopecia areata, those with extensive alopecia
areata, and those in whom the duration of alopecia areata was
2 years or more.
However, there is no strong evidence to suggest that drug-induced
remissions or therapies alter the course of alopecia areata, and
it is increasingly clear that the available treatment options
at best manage to suppress the underlying process. Early intervention
is crucial, and most patients can be offered hope and support
to help them cope with the months of treatment usually needed
to achieve reduction in disease symptoms. Intralesional therapy
is immunomodulatory in action, and new-targeted therapies are
needed especially for children, and for those with chronic persistent
disease.
Precautions
and side effects of intraleisonal corticosteroid treatment
In any dermatological condition, the ideal treatment would be
one that is effective, easy to apply, painless, free of side effects,
and inexpensive. Therapeutic management should always be commenced
with the treatment module that fulfills as many of these criteria
as possible, and should always be undertaken by dermatologist
or a physician with experience in the treatment of hair diseases.
The two main complications of intralesional steroid therapy include
pain with drug delivery and transient atrophy of the skin (wasting).
Large depot injections should be avoided, as this can lead to
tissue
loss and severe depression of the skin. If injections are given
too frequently and if atrophied areas are re-injected, this atrophy
may become permanent and interfere with hair re-growth. Blood
vessel occlusion and uniocular amaurosis (blindness) have been
reported with the administration of intralesional hydrocortisone
suspension and methylprednisolone acetate suspension to the frontal
and/or temporoparietal region. This complication is rarely seen
now because of the availability of solutions containing microsize
steroid particles.
If injections are done on a regular basis in the periocular area,
a baseline eye exam and regular follow-up examinations are recommended
to check for glaucoma (an eye disease characterized by abnormally
high intraocular fluid pressure) and/or cataracts (opacity of
the lens or capsule of the eye, causing impairment of vision).
Intralesional corticosteroid therapy is a therapy for which partial
success has been claimed and is more effective in those with milder
forms of the disease and is much less effective in people with
extensive hair loss. Large areas obviously cannot be treated because
the discomfort and the high dosage of medication can result in
side effects similar to those of the oral regimen. One cannot rule
out the risk of systemic absorption of the steroid with all its
associated side effects if the injected doses are
too high or too frequent.
Intralesional
corticosteroids for alopecia areata references
- Kubeyinje EP. Intralesional triamcinolone
acetonide in alopecia areata amongst 62 Saudi Arabs. East Afr
Med J. 1994 Oct;71(10):674-5.
PMID: 7821250
- Selmanowitz VJ, Orentreich N. Cutaneous
corticosteroid injection and amaurosis. Analysis for cause and
prevention. Arch Dermatol. 1974 Nov;110(5):729-34. PMID: 4422330
- Abell E, Munro DD. Intralesional treatment
of alopecia areata with triamcinolone acetonide by jet injector.
Br J Dermatol. 1973 Jan;88(1):55-9. PMID:
4686543
- Porter D, Burton JL. A comparison
of intra-lesional triamcinolone hexacetonide and triamcinolone
acetonide in alopecia areata. Br J Dermatol. 1971 Sep;85(3):272-3.
PMID: 5111692
- Orentreich N, Sturm HM, Weidman AI, Pelzig A. Local injection
of steroids and hair regrowth in alopecias.
Arch Dermatol. 1960 Dec;82:894-902. PMID:
13731135
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