<Things you should know> Correct knowledge about "Keratosis pilaris" (1) Explanation of the causes and symptoms of keratosis pilaris
During puberty, many people have probably wondered what these small bumps on their upper arms, thighs, and other parts of their skin could be. These bumps are actually a skin condition called keratosis pilaris.
Here, under the supervision of a dermatologist, we will introduce the symptoms of keratosis pilaris and who is prone to developing it.
What is keratosis pilaris?
First, let's look at the characteristics and symptoms of keratosis pilaris, and the conditions that make someone more susceptible to developing it.
What is keratosis pilaris?
Keratosis pilaris is a skin condition characterized by numerous keratinized, millet-grain-sized bumps in the pores of the skin. It is a type of "keratosis pilaris," where excessive keratinization occurs in the hair follicles (the tissue surrounding the hair roots), and is sometimes called "shark skin." It mainly occurs on the upper arms, but as will be explained in more detail later, it can also occur on the thighs and other areas.
Keratosis pilaris is indeed a skin condition, but it's a common one, affecting about 30-40% of teenagers. If you're not bothered by the appearance, treatment is rarely necessary; it's better to think of it as a bothersome skin symptom rather than a disease.
The condition typically begins around the age of 5 or 6, when children enter elementary school, and becomes most noticeable during adolescence. After that, the severity of the condition naturally subsides with age, and it becomes less noticeable after the age of 30.
What are the main symptoms of keratosis pilaris?
As mentioned earlier, keratosis pilaris causes small bumps in the pores of the skin. The rash feels rough to the touch, but it rarely causes pain or other noticeable symptoms. The pores where the rash occurs become enlarged and clogged with keratin plugs. The size of the rash is approximately 1 to 3 mm. In addition, the rash may be red or the skin may become discolored due to hyperpigmentation.
Furthermore, it is not uncommon for "facial follicular erythema melanosis" to occur in combination with keratosis pilaris. Facial follicular erythema melanosis is a skin condition mainly seen in adolescent men, characterized by reddish rashes from the ears to the cheeks. Like keratosis pilaris, it usually resolves spontaneously with age, and in most cases, no special treatment is necessary.
Areas where keratosis pilaris is likely to develop
Keratosis pilaris most commonly occurs on the upper arms, but it can also appear on other parts of the body.
- shoulder
- Back (the back around the shoulder blades)
- Buttocks
- Thighs
In rare cases, it can also occur on the trunk and distal limbs. It can be described as a skin disease that can affect a wide range of areas of the body.
Who is most likely to develop this condition?
The following conditions are considered to make you more susceptible to developing keratosis pilaris:
- Someone in my family has keratosis pilaris.
- Ichthyosis vulgaris (a condition in which the skin becomes dry and peels off) is observed.
- Atopic dermatitis is present.
- Obese
It is said that rashes are particularly noticeable in obese individuals.
Furthermore, there is no difference in incidence between men and women. Although it is often thought that it is more common in women because women tend to be more concerned about the appearance of the affected area, there is no difference due to gender.
It should be noted that keratosis pilaris is not contagious.
The mechanism of keratosis pilaris
As briefly mentioned earlier, keratosis pilaris occurs when keratinization of the hair follicles within the hair pores progresses excessively. Keratinization is a series of processes in which "basal cells," located in the deepest part of the epidermis, change shape into spinous cells and then granular cells, gradually being pushed to the surface. Through this keratinization process, the basal cells born deep within the skin eventually become the hard keratin on the surface of the skin.
Keratinization itself is a normal function of skin and is not necessarily a bad thing. However, if this cycle continues to occur at a faster-than-normal rate, it can lead to keratosis pilaris, a type of keratosis pilaris.
Supervised by: Dr. Tomoko Fujimoto, Director of Ikebukuro Nishiguchi Fukuro Dermatology Clinic
After graduating from the Faculty of Medicine, Hamamatsu University School of Medicine, he joined the Department of Dermatology at Tokyo Medical and Dental University. Subsequently, he served as an assistant professor at the same university, and as chief of dermatology at Tama Southern Regional Hospital and Tokyo Metropolitan Otsuka Hospital before opening Ikebukuro Nishiguchi Fukuro Dermatology Clinic. He is a certified dermatologist by the Japanese Dermatological Association.