Melanonychia refers to a condition involving your toenails or the nails of your fingers. In this condition, black or brown lines tend to appear on your nails. This decolorization usually appears in the form of a stripe that begins at the bottom of the nail bed and comes all the way up to the top.
Melanonychia can occur in one or multiple nails. Sometimes, these lines naturally occur on your nails, especially if you have a dark complexion.
What are the causes of melanonychia? There can be multiple reasons why you are suffering from this condition. Therefore, it is important that you get an appointment fixed with a doctor.
This is also important because sometimes, melanonychia might be associated with a dangerous health issue.
Keep reading to know about melanonychia, also known as longitudinal melanonychia or melanonychia striata.
What are the Types of Melanonychia?
Broadly speaking, there are two different forms of melanonychia:
- Melanocytic activation: In this type, there is an increase in the production of melanin in your nails leading to an increased deposit of this pigment. However, no increase in the pigment cells is observed.
- Melanocytic hyperplasia: In this type of melanonychia, there is an increase in the pigment cells present in your nail bed.
What can be the Causes?
The nails of your fingers and toes are translucent and do not contain any pigments. Melanonychia, on the other hand, occurs as soon as the pigment cells, also called as the melanocytes, start depositing melanin pigment into your nails.
Melanin is a type of pigment with brown color which gets deposited into your nails and starts accumulating. As the nail grows, it causes black or brown stripes to appear on your nails.
What causes melanocytes to start depositing melanin in your nails? There are two processes, each with a different set of causes.
The melanocytic activation may be caused by:
- racial variations
- carpal tunnel syndrome
- any deformity in foot causing friction in the shoes
- lichen planus
- nail infection
- skin cancer
- viral warts
- Cushing syndrome
- Addison’s disease
- Skin cancer
- Dysfunction of the growth hormone
- Having too much iron in the body
- Exposure to phototherapy
- Exposure to X-ray
- Consumption of chemotherapeutic drugs
- Consumption of anti-malarial drugs
Melanocytic hyperplasia, on the other hand, may be triggered by:
- Cancer of the nails
- Birthmarks or moles (benign most of the time)
- Benign lesions
Beyond the two primary reasons mentioned above, melanonychia may be caused by:
- Certain types of bacteria
- Hair dye
- Silver nitrate
Sometimes, genetics may also play a role. For example, people with an African descent are more likely to experience melanonychia as compared to other races.
What are the Treatment Options?
The treatment for melanonychia varies from person to person and mainly depends upon the underlying cause. If your condition is occurring due to a benign cause which is noncancerous, there may be no need of undertaking any treatment.
If the condition is being caused by a certain medication, the doctor may ask you to stop taking it or change it altogether if possible. If you are unable to stop taking the specific medication, you may have to live with melanonychia for the rest of your life as a side effect to the drugs you are taking.
Some other treatment options that depend upon the primary cause include:
- Using an antifungal or antibiotic medication, especially if the cause is any underlying infection
- Treating any underlying medical condition or disease which is triggering melanonychia
If the melanonychia is cancerous or malignant, you may just have to get the affected area completely removed. This may mean that you will have to let go the whole of your nail or a small part of it. In certain cases, the toe or the finger that has the tumor may have to be detached to protect the rest of the body.
You can get a diagnosis of melanonychia after running a series of diagnostic tests and exams. The doctor will start off with a physical exam in which they will check all the nails of your fingers and toes one by one.
This exam will cover different areas and confirm if there are any broken or deformed nails, the total number of nails affected with melanonychia, and the shape, color, and size of the condition.
The doctor may also check your previous medical history and take a lot at all the drugs that you are using at the moment. This is to see if there is a preexisting medical problem or a certain drug that is triggering melanonychia in your nails.
The next step of the examination involves the dermatoscopic examination with the help of a special type of microscope. This step is required to get a closer look at the discolored areas. During this step, the doctor will search mainly for the signs if the melanonychia is malignant.
The following signs determine if your melanonychia is malignant:
- Presence of brown pigment which is irregular
- Deformity in the nail
- Presence of grey or black color in addition to the brown hue
- Granular looking pigmentation
- Discoloration of more than two-thirds of your nail plate
In addition to looking for the symptoms of possible cancer, the doctor may also combine the findings gathered from the physical exam and dermoscopy to know the type pf melanonychia and its cause.
After accomplishing these two steps, a doctor may proceed with the biopsy of the nail. This requires removing a small part of your nail along with the nail tissue. This part of the nail is then placed under a microscope and stained with different dyes to check for possible symptoms.
This step is mostly performed in the cases of melanonychia unless you are unable to find any signs of possible cancer. A biopsy is an extremely important step in diagnosing melanonychia and discovering its cause. It will also tell the doctor for sure if your melanonychia is benign or malignant.
Can there be any Complications?
Some of the possible complications of melanonychia include bleeding under the nail, cancer, deformity of the nail, or nail splitting. The biopsy itself may lead to the deformity of nails since it includes removal of a small part of the nail.
The Bottom Line
The outlook for most causes of benign melanonychia is good and there is no treatment required. However, remember that this condition does not tend to go away on its own.
The outlook for the malignant cases of melanonychia, on the other hand, is not as good. This problem requires a complete removal of the tumor which sometimes includes amputating the whole toe or finger.
Cancer of the nails is also quite challenging to detect in the early stages, mostly because it is quite similar to the benign types of melanonychia. However, with proper biopsy, cancer can be caught and treated at the right time.