There is a large variety of nail diseases that span an array of different conditions. Fungal and bacterial infections are the most common causes and are often the underlying root of most nail disorders. Common instances include yeast infection and infection by dermatophytes, a class of fungi that includes athlete's foot and ringworm of the skin. Other less-serious nail diseases involve disfigurements and blemishes of the nail and can originate from injury, trauma, nutritional deficiencies or genetics. These include white spots, ingrown nails, ram's horn nails, spoon nails and onychoptosis, or nail shedding.
Fungal infections of the nail are most often characterized by discoloration, increased roughness and crumbling of the nail. Yeast infections are more common in fingernails, whereas dermatophyte infections are more common in toenails. Most infections result in onycholysis, a separation of the nail plate from the skin, with visible debris underneath. This is caused by the fungus digesting the keratin protein of which the nail is made, and if left untreated, the nail might eventually break down and fall off. Fungal infections can sometimes be treated with topical creams but are most effectively cured through oral medications.
Bacterial infections are characterized by redness, swelling and pain around the nails. They are most commonly caused by an injury to the area or by overexposure to chemicals or water, and they can be highly contagious in certain cases. Bacteria can enter the nail either through the side folds of the nail or from underneath the nail plate. These bacteria are referred to as paronychia and pseudomonas, respectively, with the latter often resulting in a greenish discoloration. If untreated, the infection might eventually cause the nail plate to lift and fall off.
White spots, while extremely common, are among the least harmful of all nail diseases. The majority of them are caused by simple air bubbles underneath the nail. These are usually caused by trauma, though they might also be partially hereditary. In most cases, the white spots will grow out with the nail, and no treatment is required. In rarer, more severe cases, a large number of white spots clearly not caused by injury might indicate infection.
Ingrown nails are common among the less adverse nail diseases, and they cause the nail to grow into and cut the nail bed. They are more common in toenails, suggesting that pressure from walking or tight shoes is a primary factor. Most cases are noninfectious, and properly trimming and rounding off the nail is a satisfactory treatment. In serious cases usually involving infection, surgery might be necessary.
Ram's horn nail is a nail disease characterized by increased thickness and curving of the nail. This is a result of an injury to the matrix of the nail, and it can be hereditary or can be caused by long-term neglect. Typically, ram's horn nails are brownish, thick and difficult to cut, often aggravating the condition. Consistent and frequent trimming is the most effective long-term solution.
Spoon nails usually affect the fingers and are characterized by unnaturally thin nails that are curved or wavy, with raised ridges. These are most often the result of an iron deficiency, and they typically undergo a process in which they grow thinner and become brittle before finally becoming spoon-shaped. A physician's advice is normally the best bet to treating the deficiency properly.
Onychoptosis literally means "falling nail" and is characterized by the shedding of the toenail. Its most common causes are traumatic injury and prolonged infection. Periodic shedding also can be a byproduct of syphilis, fever or an adverse reaction to prescription drugs.