Unexplained Black Spots on Skin: Possible Causes and Solutions

Unexplained black lesions on the skin?

Hello doctor, my skin has been like this for two to three years.
It doesn't hurt or itch unless I touch it, and deeper areas feel normal while shallower areas feel slightly raised (the calf is more sensitive).
Since it's on the back of my leg, I usually don't notice it.
It extends from my thigh to my calf to my ankle, and I suddenly noticed many black, block-like formations of varying shades, but only on my left leg.
I also had blood tests done at the rheumatology and immunology department, and all the reports came back normal.
I'm not sure what the issue could be.

33, 20~29 year old female. Ask Date: 2019/06/24

Dr. Huang Hongshuo reply Family Medicine

I apologize for the delayed response.
Could you please provide any photos for reference? Based on the description of the symptoms, it seems to be a lesion in the superficial skin or subcutaneous tissue.

Reply Date: 2019/06/24

More Info

Unexplained black spots on the skin can be concerning, especially when they appear without any accompanying symptoms such as pain or itching. Based on your description, it seems that you have developed these spots over a period of two to three years, primarily on your left leg, extending from the thigh down to the ankle. The fact that they are not painful or itchy is a positive sign, but it still warrants further investigation.

There are several potential causes for the appearance of black spots on the skin. One common cause is hyperpigmentation, which can occur due to various factors such as sun exposure, hormonal changes, or skin trauma. In some cases, post-inflammatory hyperpigmentation can develop after an injury or inflammation, even if the initial issue was minor. This could explain why you have noticed these spots without any recent trauma.

Another possibility is a condition known as acanthosis nigricans, which is characterized by dark, velvety patches of skin, often found in body folds. This condition is frequently associated with insulin resistance and can be a marker for metabolic syndrome or diabetes. Given your concern about the black spots and their persistence, it may be worth discussing your overall health and any potential metabolic issues with your healthcare provider.

Additionally, certain skin conditions, such as lentigines (often referred to as age spots or liver spots), can also present as dark spots on the skin. These are typically benign and result from sun exposure over time. However, since you mentioned that these spots are somewhat raised in certain areas, it might be worth considering other dermatological conditions, such as seborrheic keratosis, which are also benign but can appear as dark, raised lesions.

Given that you have already undergone blood tests with normal results from a rheumatology and immunology perspective, it is essential to follow up with a dermatologist. A dermatologist can perform a thorough examination of your skin and may recommend a biopsy if there is any uncertainty about the nature of the spots. This is a crucial step in ruling out any serious conditions, including skin cancers or other dermatological disorders.

In the meantime, here are some general recommendations to consider:
1. Sun Protection: Always apply sunscreen to the affected areas when exposed to sunlight. UV exposure can exacerbate hyperpigmentation and lead to further darkening of the spots.

2. Moisturization: Keep your skin well-moisturized to maintain its barrier function and overall health. This can help prevent any potential irritation that might arise from dryness.

3. Avoid Scratching or Picking: Although the spots are not itchy, avoid any actions that could irritate the skin further, as this can lead to inflammation and potentially worsen hyperpigmentation.

4. Monitor Changes: Keep an eye on the spots for any changes in size, shape, or color. If you notice any significant changes, it is crucial to seek medical advice promptly.

5. Healthy Lifestyle: Maintaining a balanced diet, staying hydrated, and managing stress can positively impact your skin health and overall well-being.

In conclusion, while the black spots on your skin may not be causing immediate discomfort, it is essential to consult with a dermatologist for a comprehensive evaluation. They can provide a definitive diagnosis and recommend appropriate treatment options tailored to your specific condition. Early intervention can often lead to better outcomes, so do not hesitate to seek professional advice.

Similar Q&A

Dealing with Raised Dark Spots on Skin: Causes and Solutions

I have been troubled for several years by small, round, slightly raised black spots that feel a bit bumpy. What methods are available to address this issue? I appreciate the hard work of the doctors in answering my questions.

Dr. Li Yufen reply Dermatology
Hello: It is not possible to diagnose skin diseases based solely on a textual description. If the skin lesions do not improve or worsen, it is advisable to consult a nearby dermatologist for a diagnosis. A definitive diagnosis is necessary to determine the appropriate treatment m...

Understanding Yellowish Skin with Black Spots: Dermatology Insights

There is a yellow-green patch of skin on my body that appears yellow with black spots. The black spots become more noticeable when I stretch the skin, but they don't look very dark, and there are many of them. The location is on the right side of my waist, and the spots are ...

Dr. Wu Yuxin reply Dermatology
Please seek medical attention! It's unclear what issue you are trying to express.

Understanding Back Acne: Causes and Effective Treatments

I have acne and dark spots on my back. I want to know what I should use to treat it and why it is happening!

Dr. Li Yufen reply Dermatology
Hello: It is not possible to diagnose skin diseases solely based on a textual description. If the black spots are related to acne, they may be clogged comedones or post-inflammatory hyperpigmentation. For more information about acne, you can refer to the detailed introduction on ...

Understanding Skin Discoloration: Possible Causes and When to Seek Help

Dear Doctor, I would like to inquire about a skin issue concerning my friend's father, who is around 50 years old. He has been reluctant to seek medical attention, so I am seeking help online. For about a year, he has developed strange white patches on his cheeks, which sta...

Dr. Hong Zhengsheng reply Dermatology
Hello, Xiao Hei: Age spots, keratosis, and skin proliferative disorders are all possible causes. I apologize for not being able to provide a diagnosis based solely on your description. My best advice is to consult a trusted dermatologist. I recommend that when you notice the symp...