3. Definition
Different fungal organisms may infect the nails, with
different patterns of presentation, affecting any part
of the nail from the nail bed to the nail matrix and
plate.
The most common result is a poor cosmetic
appearance of the affected nail(s); however, the
condition may also cause pain, disfigurement and
functional impairment.
4. Epidemiology
This is one of the most commonly occurring
dermatological conditions.
prevalence reports a range from 3-26%
worldwide.
The incidence of new cases of onychomycosis
(OM) appears to be rising due to the increasing
prevalence of diabetes and more ageing
population.
5. Risk factors
Age : adults are 30 times more likely than children to
suffer the condition.
Immunosuppression illness or medications that
suppress immune responses greatly increase the
likelihood of developing OM.
Diabetes mellitus
Cutaneous fungal infection co-exists with OM in about
30% of cases.
Living in a warm, humid climate.
Participation in athletic/sporting activities, regular
communal bathing and occlusive footwear.
Prior trauma to the nail.
6. Infecting organisms
Dermatophytes causes over 90% of cases.
Yeasts : These cause 8% of total infections, particularly
Candida albicans.
Non-dermatophyte moulds These cause about
1-10% of total infections in the general population -
However, they are the predominant causative
organisms in patients who also have HIV.
9. Distal and lateral subungual
onychomycosis (DLSO)
•Nearly always caused by dermatophytes
Can either affect a healthy nail or one already diseased - eg, by
psoriasis.
•Affect the hyponychium (epithelium of nail bed), often at the lateral
edges initially.
•Spread proximally along the nail bed, causing creamy/buff
discolouration, subungual hyperkeratosis and onycholysis.
The nail plate is not affected initially but may become so in time.
•May be confined to one side of the nail or spread sideways to
involve the whole nail bed.
10. Superficial white onychomycosis
(SWO)
SWO is less common than DLSO:
It is usually due to dermatophyte infection .
It presents as white chalky plaque on the proximal nail
plate, almost exclusively on the toenails.
The surface of the nail plate is affected rather than the
nail bed. The nail plate may become eroded and even
lost.
There is white rather than creamy discolouration.
Onycholysis is not usually a feature.
Concurrent tinea pedis is less common than in DLSO.
11. Superficial white
onychomycosis (SWO)
•SWO is less common than DLSO
•It is usually due to dermatophyte infection .
It presents as white chalky plaque on the
proximal nail plate, almost exclusively on the
toenails.
•The surface of the nail plate is affected rather
than the nail bed. The nail plate may become
eroded and even lost.
•There is white rather than creamy
discolouration.
12. Proximal subungual
onychomycosis (PSO)
•PSO is uncommon:
•Candidal OM occurs in three different
types:
•Candidal paronychia: initially
appears as oedema, erythema and
pain of the nail fold, from which pus
can be expressed.
•Subungual abscess with DLSO
•Total nail dystrophy
•Causes chronic paronychia with
secondary nail dystrophy.
13. Total dystrophic
onychomycosis (TDO)
•Represents a long-standing,
severe, end-stage disease
progressing from all the above
clinical patterns.
•Complete destruction of the
nail plate is observed.
14. Differential diagnosis
Only about 50% of discoloured or dystrophic-appearing nails have a
fungal infection confirmed with dermatophyte on culture. Other
causes include:
Onychogryphosis (thickening and distortion of the nail, typically of
the big toe, thought to be due to previous nail bed trauma).
Trauma (tight shoes, nail biting).
Poor foot care.
Eczema (irritant or allergic contact dermatitis).
Lichen planus.
Subungual melanoma.
Raynaud's phenomenon
Bacterial paronychia - eg, Pseudomonas spp. infection.
Systemic disease - eg, thyroid disease, diabetes, peripheral arterial
disease.
15. Investigations
Nail material should be sent for microscopy. There is
a high false negative rate (30-40%)
Culture of nail material should also be undertaken,
as this increases sensitivity and will determine
species but may take several weeks.
Nail histology is not usually necessary unless there
is reason to suspect another cause of nail pathology,
such as psoriasis.
Polymerase chain reaction is an effective method of
detecting dermatophytes but is not used in routine
practice.
17. Associated diseases
Diabetes mellitus
Any cause of immunocompromise
Raynaud's phenomenon
Peripheral arterial disease
Tinea pedis
Occupational dermatitis of hands
Psoriasis
Nail trauma
18. How to recognize Nail Fungus?
Nail fungus is made up of tiny organisms (Tinea
Unguium) that can infect fingernails and toenails.
The nails of our fingers and toes are very effective
barriers. This barrier makes it quite difficult for a
superficial infection to invade the nail. Once an
infection has set up residence however, the same
barrier that was so effective in protecting us
against infection now works against us, making it
difficult to treat the infection.
19. Is Nail Fungus contagious?
Yes, it can be.
The organisms can sometimes spread from one person
to another because these critters can live where the air
is often moist
This can happen in places like shower stalls,
bathrooms, or locker rooms or it can be passed around
on a nail file or emery board. So, don't share them.
Nail fungus may also spread from one of your nails to
other nails.
20. Nail Fungus: Treatment &
Prevention.
The best treatment of course is prevention.
Keep your nails cut straight across. If nails are hard to
cut, soften by soaking in salt water (use 1 teaspoon per
gallon of water and then dry well).
Keep feet dry and well ventilated.
Be careful with artificial nails and be selective about
choosing your manicurist. Ask about how they sterilize
their instruments. See a podiatrist or your health care
provider if you see signs of fungus.
22. Cosmetic treatment
Referral to a chiropodist may be helpful.
Nail filing and nail polish can lessen cosmetic effects.
It is helpful to trim dystrophic nails.
In DLSO, remove nail and hyperkeratotic nail bed
with clippers.
In SWO debride abnormal nail with a curette.
23. Medical treatment
Topical therapy
They should be reserved for mild distal disease in up to two nails,
cases of SWO or where there are contra-indications to systemic
therapy.
Treatment should be given daily for six months to one year.
Can be used in cases of SWO or early DLSO where infection is
confined to the distal edge of the nail.
5% amorolfine is effective and appears to be the best topical agent in
terms of its ability to penetrate the nail matrix.
28% tioconazole is also available but the evidence base for its
effectiveness is weak.
Newer topical therapies such as tavaborole, efinaconazole and
luliconazole are being explored.
Evidence for combination treatment with oral and topical antifungals
is weak and not currently recommended.
24. Systemic therapy:
Systemic treatment is recommended for most
people, as it is more effective. The slow growth
of nails means that they do not appear normal
even after effective treatment.
Terbinafine
Currently first-line with evidence of greater
efficacy compared to itraconazole.
Itraconazole
Griseofulvin
25. Side-effects of systemic
antifungals
headache
itching
loss of sensation of taste
gastrointestinal symptoms
rash
fatigue
abnormal liver function.
26. Surgery
Nail avulsion, removal of nail plate,
chemical treatments (eg, 40-50% urea
solution for very thickened nails) and
matrixectomy may enhance the
effectiveness of oral treatment.
27. Complications
Poor cosmetic appearance of hands/feet.
Disfigurement and total destruction of the nail plate.
Paronychia.
Damage to diabetic feet.
Cellulitis, osteomyelitis, sepsis and necrosis in elderly
patients and people with diabetes.
Psychosocial problems due to embarrassment at
cosmetic appearance.
Pain and limitation of function, particularly in older
patients.
28. Prognosis
The prognosis is variable and depends on the
type of infection as well as host factors such as
comorbidities and age.
Fingernail infections usually have much higher
cure rates 70%.
Untreated, fungal nail disease is usually
progressive, leading to gradual destruction of the
nail plate.
29. R e f e r e n c e S
Eisman S, Sinclair R; Fungal nail infection: diagnosis and
management. BMJ. 2014 Mar 24;348:g1800. doi: 10.1136/bmj.g1800.
Hwang SM, Suh MK, Ha GY; Onychomycosis due to
nondermatophytic molds. Ann Dermatol. 2012 May;24(2):175-80.
Epub 2012 Apr 26.
Szepietowski JC, Reich A; Stigmatisation in onychomycosis
patients: a population-based study. Mycoses. 2008 Sep 12.
Grover C, Khurana A; Onychomycosis: newer insights in
pathogenesis and diagnosis. Indian J Dermatol Venereol Leprol.
2012 May-Jun;78(3):263-70.
Rosen T, Friedlander SF, Kircik L, et al; Onychomycosis:
epidemiology, diagnosis, and treatment in a changing landscape.
J Drugs Dermatol. 2015 Mar;14(3):223-33.
30. Hoy NY, Leung AK, Metelitsa AI, et al; New concepts in median nail
dystrophy, onychomycosis, and hand, foot, and mouth disease nail
pathology. ISRN Dermatol. 2012;2012:680163. Epub 2012 Jan 26.
Lee MH, Hwang SM, Suh MK, et al; Onychomycosis caused by
Scopulariopsis brevicaulis: report of two cases. Ann Dermatol. 2012
May;24(2):209-13. Epub 2012 Apr 26.
Westerberg DP, Voyack MJ; Onychomycosis: Current trends in
diagnosis and treatment. Am Fam Physician. 2013 Dec 1;88(11):762-70.
Tracey C et al; How to Treat Dystrophic Nails, Podiatry Today, 2013
Fungal Skin and Nail Infections: Diagnosis and Laboratory
Investigation - Quick Reference Guide for Primary Care; GOV.UK
British Association of Dermatologists’ guidelines for the
management of onychomycosis 2014; British Association of
Dermatologists
Fungal nail infection; NICE CKS, September 2014 (UK access only)