Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
Many changes in fingernails or toenails may cause people to think they have a fungal infection of the nails, medically known as onychomycosis.
Fungal infection of the nails sometimes makes the condition sound contagious or related to poor hygiene. In fact, up to 10% of all adults in Western countries have fungal infection of the nails. This percentage increases to 20% of adults who are age 60 or older.
In reality, abnormal-looking nails may be caused by a number of conditions including, but not limited to, fungal infection. There are many other reasons why your nails may look different.
What other conditions can be mistaken for fungal nails?
Here are some other conditions you may have instead of fungal nails:
Lines and ridges: These are common and may be considered normal. They may worsen during pregnancy. A large groove down the center of the nail can be caused by nail biting.
Senile nails: As you age, the nails become brittle, develop ridges and separation of the nail layers at the end of the nail. To avoid this, try to clean solutions, and don't soak the nails in water.
Whitish or yellowish nails can occur due to onycholysis. This means separation of the nail from the nail bed. The color you see is air beneath the nail. The treatment is to trim the nail short, don't clean under it, polish if you want to hide the color, and wait two to three months.
Red or black nails due to a hematoma, or blood under the nail, usually occur from trauma (like whacking yourself on the thumb with a hammer). The discolored area will grow out with the nail and be trimmed off as you trim your nails. If you have a black spot under your nail that was not caused by trauma, you may want to see a dermatologist to make sure it is not melanoma.
Green nails can be caused by Pseudomonas bacteria, which grow under a nail that has partially separated from the nail bed. The treatment is to trim the nail short every four weeks, don't clean it, polish if you want to hide the color, and wait two to three months. It is also advised to avoid soaking the nail in any sort of water (even if inside gloves) and to thoroughly dry the nail after bathing. If the problem continues, there are prescription treatments that your doctor may try.
Pitted nails may be associated with psoriasis or other skin problems that affect the nail matrix, the area under the skin just behind the nail. This is the area from which the nail grows. Nails affected by psoriasis can also be tan in color.
Swelling and redness of the skin around the nail is called paronychia. This is an infection of the skin at the bottom of the nail (cuticle). If the infection is acute (has a rapid onset), it is usually caused by bacteria. It may respond to warm soaks but will often need to be drained by a doctor. A chronic paronychia occurs when a cuticle becomes inflamed or irritated over time. Sometimes, yeast will take advantage of the damaged skin and infect the area as well. Therapy begins with keeping the skin dry and out of water. Sometimes a steroid cream such as hydrocortisone can be used with success. If the problem continues, a physician
should be consulted.
Chronic nail trauma, such as repeatedly starting and stopping, kicking, and other athletic endeavors, can cause damage to the nails that can look a lot like fungal nails. This sort of repetitive trauma can also occur with certain types of employment or wearing tight-fitting shoes.
Onychomycosis is a fungal infection usually caused by a special type of fungus known as a dermatophyte.
Since most of these infections are relatively superficial, it would seem that topical treatments ought to work well. This is not the case because the nail unit is relatively impenetrable.