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Indian Journal of Dermatology, Venereology and Leprology
Medknow Publications on behalf of The Indian Association of Dermatologists, Venereologists and Leprologists (IADVL)
ISSN: 0378-6323 EISSN: 0973-3922
Vol. 71, Num. 6, 2005, pp. 386-392
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Indian Journal of Dermatology, Venereology and Leprology, Vol. 71, No. 6, November-December, 2005, pp. 386-392
Review Articles
Nail changes and disorders among the elderly
Singh Gurcharan, Haneef NayeemSadath, A Uday
Department of Dermatology and STD, Sri Devaraj Urs Medical College, Tamaka, Kolar
Correspondence Address:108 A, Jal Vayu Vihar, Kammanhalli, Bangalore-560043,
gurcharan@vsnl.com
Code Number: dv05130
Abstract Nail disorders are frequent among the geriatric population. This is due in part to the impaired circulation and in particular, susceptibility of the senile nail to fungal infections, faulty biomechanics, neoplasms, concurrent dermatological or systemic diseases, and related treatments. With aging, the rate of growth, color, contour, surface, thickness, chemical composition and histology of the nail unit change. Age associated disorders include brittle nails, trachyonychia, onychauxis, pachyonychia, onychogryphosis, onychophosis, onychoclavus, onychocryptosis, onycholysis, infections, infestations, splinter hemorrhages, subungual hematoma, subungual exostosis and malignancies. Awareness of the symptoms, signs and treatment options for these changes and disorders will enable us to assess and manage the conditions involving the nails of this large and growing segment of the population in a better way.
Keywords: Nail changes, Nail disorders, Geriatric
INTRODUCTION Nail disorders comprise approximately 10% of all dermatological conditions and affect a high percentage of the elderly.[1] Various changes and disorders are seen in the aging nail, many of which are extremely painful, affecting stability, ambulation and other functions. The prevention and management of these conditions require periodic cutting of the nails and appropriate medical care. Unfortunately, these are difficult for the elderly because of thickness of the nails, difficulty in accessing the feet, poor vision and sometimes, lack of motivation for personal care. This article reviews the age associated nail changes and disorders along with related management.
SENILE CHANGES IN NAILS
The senile changes in the nails are thought to result from impaired peripheral circulation, commonly due to arteriosclerosis.[2] Though nail plate is an efficient sunscreen,[3],[4] UV radiation may play a role in such changes. Trauma, faulty biomechanics, infections, concurrent dermatological or systemic diseases and their treatments are also contributory factors.[5],[6] The following changes are observed in human nails as part of the aging process:
a) Alteration in chemical composition
The calcium and iron contents of the aging nails are increased and
decreased respectively.[2]
b) Alteration in histology
The nail plate keratinocytes are increased in size, with increased
number of ′pertinax bodies,′which are remnants of keratinocyte
nuclei. The nail bed dermis shows thickening of the blood vessels and
degeneration of the elastic tissue, especially beneath the pink part
of the nail.[7]
c) Alteration in nail growth
Fingernails and toenails grow at an average rate of 0.1 mm/day (3.0
mm/month) and 0.03 mm/day (1.0 mm/month) respectively.[7] In
the elderly, the rate of nail growth decreases by approximately 0.5%/year
between 25 to 100 years of age.[8]
As observed by Oreintreich and Scharp (1967),[2] thumbnail
growth decreases on an average by 38% between the third and the
ninth decade. In this study, the decrease in growth of nails in females
was greater up to the sixth decade; thereafter no change was observed
till the eighth decade, whereas in males, the slowing was more pronounced
from the sixth to the eighth decade.[2]
d) Alteration in nail color
Senile nails may appear pale, dull, and opaque, with the color ranging
from white (leuconychia) or yellow to brown or grey.[7] Leuconychia
may be true (due to matrix involvement), which may be total, subtotal,
transverse, punctate or longitudinal; pseudoleu-conychia (of exogenous
origin), seen in onychomycosis, and keratin granulations after nail enamel
application; and apparent leuconychia (due to changes in the underlying
tissue).
The clinical presentations are varied like
i) Terry′s nails: The nails are colored white proximally
and have a distal normal pink band of 0.5-3 mm width. These are seen
in seen in cirrhosis of the liver, chronic congestive heart failure,
adult-onset diabetes mellitus and malnutrition.
ii) Half and half nails of Lindsay: Seen in uremic patients,
the nails have a proximal dull white area with the distal 20-60% portion
brownish.[9]
iii) Muehrcke′s paired, narrow white bands: The bands
are present parallel to the lunula. This is seen in hypoalbuminemia (less
than 2.2g/100ml),[10] nephrotic
syndrome, glomerulonephritis, malnutrition, acrodermatitis enteropathica[10] or
following chemotherapy.[11]
iv) The lunula may be decreased or absent altogether.[12],[13]
v) Neapolitan nails, which can be seen in up to 20% of the persons
older than 70 years, are characterized by three bands similar to the
colors of Neapolitan ice-cream, i.e. a proximal white portion with absent
lunula, a central normal pink band and an opaque distal free edge.[14]
e) Alteration in contour
Senile nails usually have an increased transverse curvature and
a decreased longitudinal curvature. Flattening of the nail plate (platyonychia),
spooning (koilonychia), and pincer nail deformity (involution), are found
more frequently.[8],[15]
f) Alteration in surface texture
Normally, the nails have a smooth surface. The senile nail may have
increased longitudinal striations due to altered turnover rate of the
matrix cells. The striations are termed "onychorrhexis" if they are superficial and "ridges" or "sausage-link ridges" or "beading" if
deep.[7],[8] Aging
is the commonest cause of onychorrhexis.[10] Beau′s
lines (transverse ridges) and pitting are also found frequently.[16] The
nails may be rough (trachyonychia) with splitting and fissuring.
g) Alteration in thickness
Fingernails have a normal average thickness of 0.6 mm in males and
0.5 mm in females. Toenails are thicker, 1.65 ±0.43 mm and 1.38±0.2
mm in males and females respectively.[17] The
nail plates of the thumb and great toe are the thickest, whereas the
little finger has the thinnest nail plate. In the elderly, the nail plate
thickness may increase, decrease or may remain unchanged.[7],[8]
NAIL DISORDERS AMONG THE ELDERLY
a) Brittle nails (Fragilitas unguium)
The nail plate hardness is dependent on its state of hydration, the
normal water content being 18% (10-30%). Nails become brittle when the water content is less than 16% and become soft when it is above 25%.[7] In persons older than 60 years, brittle nails are common, manifesting as excessive longitudinal ridges, roughness of the nail plate (trachyonychia), horizontal lamellar splitting of the distal nail plate (onychoschizia), and/or irregularity of the distal edge of the nail plate (Castle battlement appearance).[5],[18],[19]
Repeated cycles of hydration and dehydration, as occur in excessive domestic wet work or overuse of dehydrating agents like nail enamels, nail enamel removers and cuticle removers, may precipitate brittle nails.[5],[18],[20] The first three fingers of the dominant hand are particularly susceptible.[18]
After elimination of the exacerbating factors, local measures should be undertaken to re-hydrate the nail plate, cuticle and the nail folds. This can be achieved by soaking the nails in lukewarm water for 10 to 20 minutes, followed by application of moisturizers such as lactic acid, urea, phospholipids or mineral oils, preferably under occlusion (cotton gloves or socks).[5] Oral biotin, iron, thiamine, cysteine, pantothenic acid, PABA, have been found to be effective.[6],[21],[22] In intractable cases, formaldehyde containing nail enamels can be helpful, which should be removed and reapplied not more than once a week.[5]
b) Clubbing (Hippocratic nails/watch glass nails)
Digital clubbing is said to be present if the angle between the
normal nail plate and the skin of the finger at the proximal nail fold
(Lovibond′s angle) is less than 180°, usually close to 160°.[23]
Bilateral clubbing occurs generally (80%) due to cardiopulmonary
disease. Disorders of the liver, gastrointestinal tract and kidney may
also present with bilateral digital clubbing. Endocarditis, congestive
heart failure, cirrhosis of the liver, ulcerative colitis and chronic pyelonephritis
are the conditions commonly associated. Unilateral clubbing is seen in
lymphadenitis, Pancoast tumor of the lungs and erythromelalgia. Uni-digital
clubbing occurs in vascular lesions of the same extremity like an aneurysm,
arteriovenous fistula or peripheral shunt.[23] The syndrome of acquired hypertrophic pulmonary osteoarthropathy is a combination of clubbing, muscle weakness, joint pains, and swelling and hypertrophy of the upper and lower extremities. There is associated soft tissue proliferation, bone pain, proliferative periostitis and peripheral neurovascular disease. This condition occurs in association with a malignant thoracic tumor, especially bronchogenic carcinoma.[23]
c) Onychodystrophies from faulty biomechanics and trauma
Bony deformities of the digits or foot-to-shoe incompatibility can cause faulty biomechanics leading to onychodystrophies such as nail plate hypertrophy (onychauxis), subungual corn (onychoclavus), ingrowing toe nails (onychocryptosis), onychogryphosis, onycholysis, subungual hematoma and subungual hyperkeratosis.[5],[7]
Treatment should address the underlying bony deformity, foot care and appropriate footwear. Velcro shoes are convenient for the elderly. A molded shoe or an orthotic insert helps in non-surgical management of bony deformities.[5],[7]
d) Infections/Infestations
The nail apparatus may get primarily infected or involved in infections of the adjacent structures.
Generally, onychomycosis is the commonest nail infection, accounting
for 40% of all onychopathies and 30% of all cutaneous fungal
infections.[24] The prevalence
of onychomycosis increases with age, reaching nearly 20% in patients
over 60 years.[25] It is especially
common in the elderly, often involving both toenails and fingernails. The
great toenail is the commonest one involved. The subtypes of onychomycosis
are distal subungual onychomycosis (DSO, the commonest type), proximal
subungual onychomycosis (PSO), white superficial onychomycosis (WSO) and
candidal onychomycosis. The first three types are usually caused by dermatophytes
such as Trichophyton rubrum and Trichophyton mentagrophytes .
Non-dermatophyte molds, such as Scopulariopsis brevicaulis , Hendersonula toruloidea and Scytalidium hyalinum, are
found more frequently in the elderly.[5]
In view of the prolonged duration of therapy, multiple drug interactions
and side effects associated with the use of systemic therapies with griseofulvin
and ketoconazole, topical antifungal therapy (e.g., ciclopirox lacquer)[26] is
preferred in the elderly, although it provides only partial and symptomatic
relief.[5] Short duration therapy
or pulse therapy with itraconazole, terbinafine or fluconazole can be tried.[24] Terbinafine
is the most preferred drug because of its superior mycologic cure rates
and fewer drug interactions.[25] Nail
avulsion can be employed for severe disease affecting only one or two nails.[5],[7],[27]
Paronychia (infection/inflammation of the nail fold) can be acute or chronic.
Acute paronychia is a bacterial infection of the nail folds, usually caused
by Staphylococcus aureus or Pseudomonas species. Most
cases are trauma induced and involve only one nail.[24] Treatment
is similar to that of other bacterial infections of the skin and involves
draining of the abscess, warm saline soaks, systemic antibiotics and topical
antibiotics such as 2% mupirocin ointment.[5],[24] Severe
infections, particularly those caused by Pseudomonas , may warrant
nail avulsion.
Chronic paronychia, caused by c andida species or gram negative
bacteria ( Proteus sp. or Klebsiella sp.), appears as red,
swollen, boggy, tender nail folds with loss of cuticle and a patent proximal
nail groove. Multiple transverse ridges may be seen in the nail plate.[5],[24] Treatment
is prolonged and includes keeping the nail folds and the surrounding skin
dry, application of a topical antifungal or a topical antiseptic such as
4% thymol in alcohol and if necessary, excision of the chronic hypertrophic
proximal nail fold. In cases with severe inflammation, topical or intra-lesional
steroids can be used.[5],[24]
Sarcoptes scabiei may inhabit the subungual hyperkeratotic debris,
leading to persistent infestations or epidemics of scabies. The nails should
be cut short and fingertips should be brushed with a scabicide in affected
patients.[5]
Periungual warts are due to infection with human papilloma virus. These
occur especially in persons receiving immunosuppressive therapy.[5],[7]
The nails can be involved in leprosy, (93% in multibacillary vs 57% in
paucibacillary), leading to dry, lusterless, narrow, shrunken nails with
longitudinal ridging and subungual hyperkeratosis.[28] Onychomycosis
occurs in 32% of these patients.[29] Clofazimine
causes pigmentation of the nails.[29]
Nail changes in syphilis include dullness, brittleness, pitting, splitting
(onyxis craquelι), onycholysis, elkonyxis, shedding, distortion, Beau′s
lines in secondary syphilis, and amber coloured nails, and paronychia in
tertiary syphilis.[1],[30],[31]
e) Onychauxis/Pachyonychia
Onychauxis (localized hypertrophy of the nail plate) manifests as
hyperkeratosis, discoloration, and loss of translucency of the nail plate,
with or without subungual hyperkeratosis.[7] This
may be complicated by distal onycholysis, pain, increased susceptibility
for onychomycosis, subungual hemorrhage and subungual ulceration.[7]
Periodic partial or total debridement of the thickened nail should
be done with the help of electric drills or burrs. Chemical (40% urea
paste) or surgical avulsion may be needed. Permanent ablation with chemical
(phenol)
or surgical matricectomy may be required for recurrent and troublesome
onychauxis.[5],[7],[32]
f) Onychogryphosis
This refers to enlargement and thickening of the nail plate, which
appears "ram′s horn-like" or "oyster-like", mostly involving the
great toenail. The nail plate appears uneven, thickened and brown to opaque,
often with multiple transverse striations and hypertrophy of the underlying
nail bed. This is mainly due to infrequent cutting of the nails. Other
etiologies include trauma, hypertrophy of the nail bed and bony deformities
like hallux valgus.[5],[7] The
nail plate initially grows upwards and thereafter deviates laterally towards
the other toes, the direction of growth being influenced by pressure from
footwear and matrix activity. A few patients develop subungual gangrene
due to pressure effects, especially in the presence of diabetes mellitus
or peripheral vascular disease.[5],[18]
In hemi-onychogryphosis, a condition mimicking onychogryphosis, the nail
plate grows laterally from the beginning. This may be a complication of
persistent congenital malalignment of the great toenails. This condition
can be prevented by regular nail plate trimming and foot care.[5],[18]
Treatment is required for cosmetic reasons and for complications like subungual
gangrene. Conservative management is by filing the nail plate with an electric
drill or burr with removal of subungual hyperkeratosis, and subsequent
periodic trimming of the nail plate. Surgical or chemical nail avulsion,
with or without matricectomy, can be employed in persons with a good vascular
supply.[5],[7]
g) Onychophosis
This refers to localized or diffuse hyperkeratosis on the lateral
or proximal nail folds, in the space between the nail folds and nail plate,
and also subungually. It results from repeated minor trauma, and nail fold
and adjacent soft tissue deformities such as nail fold hypertrophy, onychomycosis,
onychocryptosis, xerosis, etc. The first and the fifth toes are commonly
affected.[5],[7]
Onychophosis can be prevented by the use of appropriate footwear to
minimize pressure effects. It is treated by debridement of the hyperkeratotic
tissue
by means of keratolytics (urea 20%, lactic acid 12% or salicylic acid 6-20%),
followed by application of emollients, thinning of the nail plate, packing
of the nail and, if necessary, surgery.[5],[7]
h) Onychoclavus (Subungual heloma/corn)
It is a hyperkeratotic process in the nail area, mostly under the
distal nail margins, due to a bony deformity or abnormal foot function.
It should be differentiated from subungual melanoma, subungual exostosis,
a foreign body or an epidermoid cyst.[5],[7] It
can be enucleated by removing the corresponding section of the nail plate
with excision of the hyperkeratotic tissue. Any bony abnormality should
be corrected and modified footwear, protective pads or tube foam should
be used to prevent recurrence.[5],[7]
i) Onychocryptosis (Ingrown nails)
This condition results when part of the nail plate pierces the lateral
nailfold. Three major types are known: over-curvature of the nail plate
(pincer nail), subcutaneous ingrowing toenail and hypertrophy of the lateral
nail fold. Clinically, it manifests as inflammation of the nail fold, often
with granulation tissue formation, sepsis, pain and tenderness of the involved
digit.[5],[7]
The causes include improper cutting of the nails, external pressure due
to ill-fitting footwear, long toes and other deformities, hyperhidrosis,
poor foot hygiene, prominent nail folds, and presence of a spicule.[5],[7] In
the elderly with impaired arterial circulation and sensation, infection
and gangrene may supervene.[5],[7]
Predisposing factors should be corrected. Any offending spicule should
be removed.[15] The distal
nail plate should be cut straight across, so that the curves of the nail
plate are beyond the distal edge of the lateral nail folds. Placing a small
wisp of cotton beneath the lateral free edge of the nail plate prevents
ingrowing.[5],[7] Warm
soaks, topical and systemic antibiotics, with application of a silver nitrate
stick or curettage to remove granulation tissue, can be done.[16] In
severe and intractable cases, complete or partial avulsion of the ingrown
nail and excision of the involved adjacent tissue (nail folds/nail bed)
can be done.[6] Other options
are partial (lateral) matricectomy with phenol, stainless steel wire nail
brace (orthonyx technique), and cryotherapy.
j) Onycholysis
Separation of the nail plate from the nail bed beginning distally
and progressing to the proximal end may be idiopathic or due to trauma,
impaired circulation.[16]
k) Onychoatrophia
This condition presents as dystrophic fingernails and toenails showing
triangular residual nail plates. This occurs as a component of Cronkhite-Canada
syndrome (alopecia, nail defects and polyposis of the gastrointestinal
tract).[33]
l) Splinter hemorrhages and subungual hematomas
Splinter hemorrhages, which are most commonly traumatic in the elderly,
are black and located in the middle or distal third of the fingernail.
In contrast, splinter hemorrhages induced by systemic disorders are red
in color and proximal in location.[5],[7]
Subungual hematomas, which are also traumatic, are red and painful when
of recent onset, and dark blue and non-tender when old. Characteristically,
these are carried forward with the growth of the nail, unlike a pigmented
lesion of the nail matrix or nail bed.[5],[7] In
a few patients, distal onycholysis with eventual auto-avulsion of the nail
plate can occur. Acute lesions should be drained to relieve pressure, by
piercing the nail plate with a needle or electric drill. In chronic cases,
melanoma should be ruled out.[5],[7]
m) Nail changes in some skin diseases
Nail involvement is very common in psoriasis and consists of pitting,
onycholysis, discoloration (yellow or green) and thickening. Although psoriasis
is the most common condition producing pitting, nail pits may also be seen
in alopecia areata, eczema involving the digits, fungal infections and
erythroderma.[16]
n) Neoplastic nail conditions
Subungual exostosis is a benign, tender, nodular, hyperkeratotic bony
proliferation most commonly involving the medial side of the great toe.
This is associated with onychodystrophy/onychoclavus of the overlying nail.[34] Trauma
and faulty biomechanics are the commonest causes in the elderly. It manifests
as an inverted ′U′shaped nail plate due to hypertrophic nail
bed, often with accentuation of the dorsal interphalangeal joint skin crease
and onychocryptosis. It may lead to pincer nail deformity.[2],[5] Treatment
is by aseptic removal of the excess bone after radiographic confirmation.[2],[5]
Myxoid pseudocysts (mucous cysts or periungual ganglion) are probably the
commonest benign tumors. They are commoner in females and usually involve
the proximal nail fold of fingers. These are asymptomatic, soft to firm,
cystic/fluctuant, sometimes causing transverse nail depressions. They can
be treated with intralesional injections of triamcinolone or surgical removal.[2]
Subungual melanoma, mostly affecting the great toe, is common in the elderly
white population. The peak incidence was in eighth decade in one study.[2] Bowen′s
disease, squamous cell carcinoma, basal cell carcinoma and glomus tumor
are also more frequent in this age group.
o) Adverse effects due to nail cosmetics
Geriatric patients may show nail changes due to prolonged use of nail
cosmetics. Nail polish may cause yellow-orange staining, superficial friability
("granulation") and brittleness of the nail plate. Allergic dermatitis
due to nail polish can affect sites other than the nail, and also the spouse
of the user. Metal pellets in the nail polish bottles may precipitate reactions
due to nickel and onycholysis. Acetone containing nail removers cause excessive
dryness of the nail plate and paronychia. Sculptured artificial nails (methyl
methacrylate), preformed plastic nails and stick on nail dressing may cause
onychodystrophy, onycholysis, thinning, splitting and discoloration of
the nail, nail fold dermatitis and loss of cuticle. Nail hardeners (formaldehyde)
may cause subungual hemorrhage and bluish discoloration of the nail. Cuticle
removers may cause irritation. Manicuring instruments may damage the nail.
The nails may also be affected by cosmetics used at other sites like
hair removers, hair tonics and bleaching agents.[3]
CONCLUSION
"The test of any civilization is the measure of consideration and care which it gives to its weaker members".
The elderly, who are one of the more vulnerable sections of our society,
show various age related changes and disorders involving the nails. These
may result in pain and interfere with their daily activities. The esthetic
aspect of the nails is significant even in the elderly, as it may affect
social as well as intra-family interactions. Awareness of the clinical
conditions affecting nails in the geriatric age group and related management
options is essential. This will help in reducing the psychological impact
of nail disorders among the aged and improve their quality of life.
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