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Nail
changes in alopecia areata
Alopecia areata is a non-scarring, inflammatory, hair loss disease
that is seen in men, women and children. There are no universally
accepted criteria to describe and classify the clinical manifestations
seen in alopecia areata, but between 10% and 66% of peole with
alopecia areata also have aberrant nail formation. The nail changes
associated with alopecia areata usually accompany the hair loss,
but may occasionally precede or follow the onset of alopecia by
months or years. The presence and severity of nail changes may
indicate a more severe and recalcitrant disease. Marked nail dystrophy
occurs more commonly in alopecia totalis (where all the scalp
hair is lost), and alopecia universalis (where there is loss of
all hair on the head and body).
The clinical aspect of the nail disease depends on the structure
of the normal nail. Therefore, to understand the abnormal nail
changes of alopecia areata, it is necessary to first be familiar
with the anatomy of the human nail. In essence, nails are just
overgrown hair follicles. Nails are made of keratin produced by
a modified form of epidermis called the nail matrix. The matrix
is in fact the root of the nail. Keratin is a protein complex,
which gives the nails its hard property. The nail plate begins
adjacent to the nail matrix and extends to the lunula, the white
half-moon shaped portion often seen at the base of the nail plate.
It is a hard keratinized structure derived from keratinocytes
within the nail matrix under the skin at the base of the fingernail.
The whitish half moons are keratin cells that have not yet been
completely flattened and still have some of their content. The
proximal and distal nail matrices generate the dorsal and ventral
nail plate, respectively. As the nail grows, the distal part of
the matrix produces the deeper layers of the nail plate, while
the proximal portion makes the superficial layers. The hyponychium
is the area between the nail plate and the end of the nail at
the fingertip. It is the junction between the free edge of the
nail and the skin of the fingertip, also providing a waterproof
barrier. The primary function of the nail is probably protection
of the fingers (and in my experience for removing staples), but
for humans the nails are mostly for show.
Types
of nail problems in alopecia areata
Despite untiring efforts by medical researchers in the field
of alopecia areata, the exact causes of the disease are still
largely unknown, and the causes of nail changes remain obscure.
However, it seems likely that because the nails are similar in
structure and growth to hair follicles, that the nails are targeted
by the same type of inflammatory cells that target hair follicles
in alopecia areata. Nail changes in alopecia areata may involve
all, some, or just one of the nails. The aberrant nail changes
as seen in alopecia areata patients include the following:
- Nail pitting is the most commonly seen abnormality and
represents irregular keratinization in the nail matrix. When
an inflammatory condition affects the nail matrix keratin is
formed
abnormally. This abnormal keratin detaches itself from the nail
plate leaving behind punctuated depressions or pits in the nail
plate.
- Longitudinal ridging or striations can also be found
and are probably a result of mild disruption of the nail matrix
which produces the nail plate.
- Koilonychia is represented by
transverse and longitudinal concavity of the nail, resulting
in a "spoon-shaped" nail.
The spoon-shaped, concave nails of koilonychia commonly occur
as a result of thinning and softening of the nail plate.
- Onychorrhexis
are brittle nails, which often split vertically, peel and/or
have vertical ridges.
- Spotting of the lunula, the white half-moon
shaped portion often seen through the nail plate.
- Onycholysis
is the distal (away from the point of attachment at the root)
separation of the nail plate from the underlying
nail bed.
- Onychomadesis is the proximal (close to the nail root)
separation of the nail plate from the nail bed, which typically
results in shedding of the nail. The precipitating event causes
complete cessation of nail matrix activity.
- Periungual erythema
or redness of the skin around the nail may be present in patients
experiencing active inflammation
in the nail matrix.
- Anonychia (absence of nails) and scarring
are not seen.
The clinical presentation of nail changes in alopecia areata
varies according to the severity and localization of the lesion.
In
essence, all these changes are the result of matrix disease.
Onycorrhexis (brittle nails), trachyonychia (roughening of
the surface of nails) and irregular pits are noted when the
proximal
part of the matrix is affected. If both the proximal and distal
parts are affected, the nail shows as a thinned plate. This
may be associated with a compensatory hypertrophy of the root
of the nail and of the hyponychium (the area between the nail
plate and the fingertip). When severe, this thinning may lead
to eventual destruction of the plate, as well as the proximal
separation of the nail plate from the nail bed (onychomadesis),
white lines or spots in the nail plate (leuconychia) or spoon
shaped nails (koilonychias).
Histology
of nail changes in alopecia areata
Fragments of nail keratin can be removed and observed by using
both light and electron microscopic techniques. Documentation
of such research shows that most of the nail changes seen in alopecia
areata have been found to be related to changes within the proximal
matrix. The extent of disease seems to be maximum within the proximal
matrix, minor in the distal matrix and negligible in the nail
bed, with the subungual (beneath the nail) keratin being largely
preserved.
Results of nails observed under light microscopy show that the
nail plate is often thin but complete atrophy is rare. A slight
parakeratosis (retention of nuclei in the cells of the stratum
corneum of the epidermis) and thin slits or even slight longitudinal
scratches of the plate can be observed. The nuclei are either
distributed homogeneously or concentrated in small centers. This
corresponds to an architectural disorder of the corneocyte arrangement
(dead cells of the horny outer layer of the epidermis), which
is shown by wave-like bands of hyperchromatic (overpigmented)
cells.
The photonic observations of nail changes in alopecia areata
reveals that the morphological abnormalities observed take on
a typical topography: they are concentrated most particularly
in the upper plate of the nail plate. Specifically, the upper
edge is disintegrating and sometimes shows little depressions,
more often thin parallel slits giving a flaky aspect. As a rule,
the subungual (beneath the nail) keratin is spared; it does not
reveal hyperchromatic blocks and usually shows only light parakeratosis.
The presence of cup-shaped dips of the upper part of the nail
plate corresponds to pits, which are very often seen clinically
as aberrant nail changes of nail in alopecia areata.
Under electron microscopy, the plate is more clearly reshaped. The cytoplasm
is full of many variably sized vacuoles (cavities), which appear either
optically empty or full of a granulous material. The dimension of those
granules is not more than 80 nm. The network of keratin fibers is also changed.
Also, the presence of nuclei or of fragments of internalized membranes in
the cytoplasm is sometimes seen. The spaces between cells are enlarged.
All these changes are common to the whole plate but more obvious in the
upper than in the lower part. As under the light microscope, the subungual
keratin shows a small change: just a few nuclear residues and a slight widening
of the intercellular spaces and a discrete disorganization of the corneocytes
can be noted.
The presence of associated nail changes in alopecia areata hair
loss can be a bad prognostic sign. Therefore, it is necessary
for the physician to be familiar with abnormal nail findings associated
with alopecia areata and also to inspect nails carefully during
physical examinations and co-relate findings to assess treatment
regimes.
Table
of references for alopecia areata in association with nail
dystrophy
In evolutionary terms, our hair follicles, nails, eyes and teeth
were all derived from the same basic structure. There are many
similarities between these organs and it has been suggested that
if the immune system can target hair follicles then why not other,
related structures? We certainly know that nails can be disrupted
in people with alopecia areata (nails are just overgrown hair
follicles). There are no recent publications on alopecia areata
and aberrant teeth - although tooth decay was believed to cause
alopecia areata by Jaquet and supporters at the turn of the century
(Jacquet 1902, Decelle 1909).
| Percentage with AA plus nail problems
| Structure
| Citation
|
| 10%
| Nails
| Samman 1978
|
| 66%
| Nails
| Horn 1980
|
| *
| Red lunulae - Nails
| Misch 1981
|
| *
| Nails
| Dotz 1985
|
| *
| Nails
| Laporte 1988
|
| 3.65%
| Trachyonchia - Nails
| Tosti 1991
|
| 46%
| Nails
| Tosti 1994
|
| *
| Trachyonchia - Nails
| Tosti 1995
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Nail
changes in alopecia areata references
- Baran R, Dawber RP, Haneke E. Hair
and nail relationship.
Skinmed. 2005 Jan-Feb;4(1):18-23. PMID: 15654160
- Olsen EA, Hordinsky MK, Price VH, Roberts JL, Shapiro J, Canfield
D, Duvic M, King LE Jr, McMichael AJ, Randall VA, Turner ML,
Sperling L, Whiting DA, Norris D; National Alopecia Areata Foundation.
Alopecia areata investigational assessment
guidelines--Part II. National Alopecia Areata Foundation. J
Am Acad Dermatol. 2004 Sep;51(3):440-7. PMID: 15337988
- Scheinfeld NS. Trachyonychia: a case
report and review of manifestations, associations, and treatments.
Cutis. 2003 Apr;71(4):299-302. PMID: 12729094
- Papadopoulos AJ, Schwartz RA, Janniger CK. Alopecia areata.
Pathogenesis, diagnosis, and therapy. Am J Clin Dermatol. 2000
Mar-Apr;1(2):101-5. PMID: 11702308
- Khoo BP, Giam YC. A pilot study on
the role of intralesional triamcinolone acetonide in the treatment
of pitted nails in children. Singapore Med J. 2000 Feb;41(2):66-8.
PMID: 11063205
- Sharma VK, Dawn G, Muralidhar S, Kumar B. Nail changes in
1000 Indian patients with alopecia areata. J Eur Acad Dermatol
Venereol. 1998 Mar;10(2):189-91. PMID: 9553924
- Noronha PA, Zubkov B. Nails and nail
disorders in children and adults. Am Fam Physician. 1997 May
1;55(6):2129-40.PMID: 9149641
- Tosti A, Bardazzi F, Piraccini BM, Fanti PA, Cameli N, Pileri
S. Is trachyonychia, a variety of alopecia
areata, limited to the nails? J Invest Dermatol. 1995 May;104(5
Suppl):27S-28S. PMID: 7738383
- Tosti A, Morelli R, Bardazzi F, Peluso AM. Prevalence of nail
abnormalities in children with alopecia areata. Pediatr Dermatol.
1994 Jun;11(2):112-5.
PMID: 8041648
- Bergner T, Donhauser G, Ruzicka T.
Red lunulae in severe alopecia areata. Acta Derm Venereol. 1992;72(3):203-5.
PMID: 1357860
- Tosti A, Fanti PA, Morelli R, Bardazzi F. Trachyonychia associated
with alopecia areata: a clinical and pathologic study. J Am
Acad Dermatol. 1991 Aug;25(2 Pt 1):266-70.
PMID: 1918465
- van der Steen PH, van Baar HM, Happle R, Boezeman JB, Perret
CM. Prognostic factors in the treatment
of alopecia areata with diphenylcyclopropenone. J Am Acad Dermatol.
1991 Feb;24(2 Pt 1):227-30.
PMID: 2007667
- Wilkerson MG, Wilkin JK. Red lunulae
revisited: a clinical and histopathologic examination. J Am
Acad Dermatol. 1989 Mar;20(3):453-7. Review.
PMID: 2645322
- Laporte M, Andre J, Stouffs-Vanhoof F, Achten G. Nail changes
in alopecia areata: light and electron microscopy. Arch Dermatol
Res. 1988;280 Suppl:S85-9.
PMID: 2457356
- Dotz WI, Lieber CD, Vogt PJ. Leukonychia
punctata and pitted nails in alopecia areata. Arch Dermatol.
1985 Nov;121(11):1452-4.
PMID: 4051533
- Shelley WB. The spotted lunula. A
neglected nail sign associated with alopecia areata. J Am Acad
Dermatol. 1980 May;2(5):385-7.
PMID: 7381066
- Horn RT Jr, Odom RB. Twenty-nail dystrophy
of alopecia areata. Arch Dermatol. 1980 May;116(5):573-4. PMID:
7377792
- Samman PD. Trachyonychia (rough nails).
Br J Dermatol. 1979 Dec;101(6):701-5.
PMID: 534617
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