Causes and Symptoms

Skin Conditions

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Nail Disease2020-01-15T09:58:07+11:00

Nail Disease

Causes & Symptoms

Discoloured, distorted or otherwise unsightly fingernails and toenails are common problems in people of all ages. Nail damage is frequently caused by injury, trauma or fungal infections. However, this may need further investigation to discover the true problem behind the condition. Nails can provide valuable clues about your overall health.

Nail Disease can often be a symptom of other skin conditions such as psoriasis, eczema and alopecia areata. In addition, an underlying internal condition can also be seen in the nails and might prompt further investigation (e.g. bulbous nails, known as clubbing, can result from disorders affecting the lungs, heart or liver).

Below is a list of commonly experienced nail problems:

Lifting of the Nail Plate (Onycholysis)

  • This is usually due to a repeated minor injury to the underside of the nail. It appears white instead of pink due to air getting under the nail. Other causes for this can also be psoriasis, fungal nail infections (onychomycosis) or water immersion.


  • This describes individual depressions around the size of a pinhead. This condition is usually seen in psoriasis and other causes such as eczema and alopecia areata (hair loss).


  • Ridging This refers to either vertical (longitudinal) or horizontal (transverse) nail ‘ridges’. Longitudinal ridging commonly appears with age and can be associated with conditions such as lichen planus and repetitive nail injury. Transverse depressions usually appear after a significant illness or due to episodes of paronychia, which is often related with nail biting.  Furthermore, fiddling with nails or cuticles can also produce irregular ridging.

Thickening of Nail (Onychogryphosis)

  • This is frequently seen in toenails, especially elderly people. Often this is a result from long term use of ill-fitting footwear and neglect of the nails. It may also be due to other medical conditions such as psoriasis or fungal infections.


  • Yellow is commonly due to a fungal nail infection (oncychomycosis). However, nails affected by psoriasis may also appear yellow. Smoking can also leave the nails yellow in colour. In rare conditions ‘yellow nail syndrome’ can be seen and is due to an underlying disorder affecting the lungs and lymphatics.
  • Green nails are usually due to a bacterial nail infection (pseudomonas) as well as infection due to a yeast called candida. Pseudomonas infection can often affect nails that have been damaged by a common fungal infection or trauma
  • Brown colouring can be caused by medications, chemicals from hair dyes, nail varnish, nicotine, trauma, chemotherapy and antibiotics. In rare conditions, melanomas may present a brown or black pigmentation on or under the nail. It is of high importance to seek medical advice to rule out melanoma in the case of a single brown or black nail.
  • White (leuconychia) nail colour may run in families or can be caused by any medical condition that results in low levels of protein in the blood.

Inflammation of the Nail Fold (Paronychia)

  • Acute infection of the nail cuticle can cause redness, swelling, tenderness and pain, sometimes with  pus formation. This is commonly a result of over-zealous manicuring or when nails are immersed in water for long periods of time. Occasionally, this condition can also be seen in infants who suck their thumbs.

Treatment at The Skin Hospital

There are many possible underlying causes of the problems mentioned above. Sometimes a diagnosis can be made without the need for any tests. Furthermore, fungal nail infections are very common; therefore a nail clipping can be taken for examination under a microscope to assess if a fungus is present. Sometimes a nail biopsy may be carried out under local anaesthetic; however this is very rarely required.

The treatment you receive will depend on the underlying cause. If your changes in the nail are due to a skin or medical condition then treatment of this problem will usually improve the appearance of the nails. However, improvements may take months to show as nails grow very slowly.

The different treatments available are:

  • Topical therapy: antifungal paints and creams may be used to treat infections affecting small parts of the nails. Topical therapies have little side effects; however, success is not guaranteed and may require many months of treatment.
  • Oral therapy: antifungal tablets (e.g. terbinafine, itraconazole, fluconazole) can be used alone or in combination with topical treatments and need to be continued for many months to have a beneficial effect. These tablets can interact with other medications and may not be appropriate in some patients. Therefore, it is important to update the treating dermatologist with your relevant medical conditions. Blood tests may be needed prior to starting treatment and during therapy.
  • Physical therapy: lasers have been shown to effectively treat fungal infection in some cases, though there is somewhat limited evidence available for this treatment. Laser treatments are available at our Darlinghurst and Westmead sites.

The Skin Hospital runs a speciality clinic dedicated to the treatment of nail disease at Darlinghurst run by Dr Hanna Kuchel. If you would like to find out more about this speciality clinic please contact us.

Dr Hanna Kuchel
Dr Tanumay Raychaudhry

Further Information

If you would like further information on nail disease the sites below provide more in-depth descriptions of nail disease:

Nail Terminology – DermNet NZ 

Find a Specialist

All our dermatologists are highly skilled in diagnosing and treating Nail Disease. Click on the link below to find a dermatologist who can help you with your skin condition.

General Dermatology