Diseases of the nail (Onychopathies)

• Nail Disorders can happen in a several skin conditions, either alone or accompanied by rashes.
• Common affections of the nails include :

1. Nail infection (bacteria, fungi, yeast and virus)
2. Paronychia: an infection of the nail fold
3. Nail disorder due to skin disease (psoriasis…)
4. Trauma to the nail

Infection of the Nails

• The commonest nail infection is due to a fungus. Fungal nail infection can affect the finger and toe nails.
• The infection reaches the nail plate from the free margin and sides of the nails. The nail plate may become brittle, thickened or completely destroyed.
• Fungal nail infection can be confirmed by microscopic examination of clippings of the nail.
• Treatment with oral antifungal tablets and/or antifungal lotion may be prescribed by your doctor. Treatment may last from 2 to 12 months depending on the type of infection and the oral antifungal tablets prescribed. However, the nail may take a few months to return to near normal appearance even after the treatment has been stopped.
• Another common nail disorder called wart is caused by viral infection of the nail fold and nail bed. The condition is called periungual warts. This condition is best treated by laser surgery.

Paronychia

• Paronychia is an inflammation of the nail folds. Nail fold damage usually results from injury to the proximal nail fold. Causes of injury include habit biting and constant wet work. People whose hands are frequently exposed to water (housewives, canteen operators, cooks…) are more prone to develop paronychia.
• Secondary infection by bacteria of fungus will cause painful swelling of the nail fold. If the infection is present for a long time, the nail plate becomes deformed.
• Treatment of paronychia includes:

1. draining pus in the infected nail fold
2. oral antibiotics.

• Topical antifungal and antiseptic lotions may be used to treat paronychia. Patients with paronychia must avoid prolonged wet-work and injury to the hands. Wearing of waterproof gloves during wet work helps to prevent paronychia.

Skin Diseases affecting Nails

• Nail changes in psoriasis are very diverse. They may appear as pits on the nail plate. The nail plate may be separated from the nail bed (onycholysis). The nail may lose its normal luster and appear discoloured. Gross thickening of the nail is another feature of psoriasis. Typical psoriasis rash is often be present on the fingers, toes and elsewhere on the body.

Nail Psoriasis: Onycholysis and “Oil Spot”

Nail Psoriasis displaying pitting and a rough surface

Trauma to the nail

• The nail can be damaged by:

1. nail-biting
2. habit-tic (scratching the nail folds, bad manicuring or industrial accident…).

• Damaged nails may appear ridged or cracked or broken.

Source of information: here