WHAT IS ONYCHOMADESIS?OnychomadesisOnychomadesis is a nail disorder in which the nail detaches from the nail bed at the top (near the cuticle). It is caused by a temporary cessation of nail growth. When the nails begin to grow again later, the new nail slides under the old, partially detached nail. The new nail slowly slides up, and eventually the detached nail falls off on its own. Onychomadesis can affect all nails simultaneously, but it can also affect only one nail.WHAT IS THE CAUSE OF ONYCHOMADESIS?Onychomadesis is caused by illnesses that temporarily stop the nails from growing. It occurs, for example, after internal illnesses accompanied by a high fever . It can also develop after chemotherapy , radiotherapy , oxygen deprivation , nail damage , and severe stress . It is always only visible after a few months, when the nails begin to grow again. It can also develop after a viral infection . The photos below show a child who had a viral infection with blisters on the hands, feet, and in the mouth (hand-foot-mouth disease). The infection has long since cleared up, but a few weeks later the nails begin to fall off. Hand-foot-mouth disease is a common cause of onychomadesis in young children. A few months later, the nails are completely normal again.
 |
 |
| onychomadesis after hand foot & mouth disease |
Onychomadesis can also occur after serious skin conditions . For example, with blistering conditions that can affect a large part of the body, such as toxic epidermal necrolysis and Stevens-Johnson syndrome (both allergic reactions to medications), erythema exsudativum multiforme (a condition with blisters and other lesions on the skin and mucous membranes), epidermolysis bullosa (an inherited blistering condition), and bullous pemphigoid (a blistering condition common in the elderly). The photos below are of a patient who had a severe blistering condition affecting his entire body, caused by medications. The skin lesions have since completely healed. However, six weeks later, it was noticed that the nails had begun to loosen. The new nails grew under the old nails. After three months, the nails were completely normal again.
 |
 |
| onychomadesis following a drug reaction |
Another cause of onychomadesis is the autoimmune disease alopecia areata . This causes patchy hair loss on the scalp, but the nails can also be affected. Onychomadesis can also occur spontaneously, without an underlying cause ( cause unknown ).
 |
 |
| alopecia areata |
cause unknown |
WHAT IS THE PROGNOSIS?The outlook is good. The new nail will naturally push the old one off. After 2-4 months, a completely healthy nail will emerge again. Toenails take longer to heal than fingernails because toenails grow much more slowly. |
