Will the little hand you owe to the child often hurt the black hand to the scalp?
(Source: soogif)
When scratching the scalp, can you often pick out some small particles?
Looking at the small particles of blood scabs and herpes in the slits of your fingers, will your little head be full of question marks?
(Source: soogif)
There are two possible scenarios.
1. Relatively healthy
Appearance: white or light yellow, small size, small grain size.
Cause: Too much oil comes out of the scalp, stasis in the ducts of the hair follicle sebaceous glands. If it is not discharged in time, it will gradually concentrate and become a granular "white head".
(Source: self-drawn)
The rest of your body secretes a lot of oil, especially your face, chest, and back, which is the "oil skin" [1].
More oil, indicating that your male hormone secretion is a bit strong. You're either a 30-60 year old tough guy or a girl who hasn't been menopausal[1], I guessed it right?
2. Relatively unhealthy
Appearance: large particles, even flaky, as large as snowflakes; at the same time, there is scalp itching, dander, etc.
Cause: Folliculitis is most likely; in severe cases, there are abscesses in the scalp hair follicles [2].
These particles that are cut down are the blood scabs, pustules, and mixtures of bacteria and fungi that grow after the abscess is broken.
Some bacteria may be causing folliculitis, but it is more likely that a fungus called "Malassezia" is also called "Furophyllum furunculosa" [2-4]. It accounts for 96% of the total number of fungal fungi on the scalp [5].
(Malassezia under a scanning electron microscope[1]. Source: Lasers Surg. Med）
Malassezia is fond of fat, and their scalps are their "cafeteria".[5]
It is also a conditional pathogen [5]. As the name suggests, Malassezia usually has nothing to do with us, and only under certain conditions will it cause disease.
For example, there is too much oil production, or low immunity, or constant unwashing of hair [3].
At this time, Malassezia can be eaten vigorously and can be vigorously grown, thus forming folliculitis.
But don't be too nervous, not as long as you can cut off the small particles, you are infected by the fungus.
If it is accompanied by itchy scalp, rashes, pustules, secretions, etc., the possibility of fungal infection is greater.
To confirm, you need to go to the hospital for a fungal test.
Malassezia multiply too fiercely, and the offspring take root in the hair follicles of the scalp, which will destroy the protective layer of the scalp - keratinocytes.
Destroyed keratinocytes fall off and can form dandruff.
(Source: self-drawn)
If the inflammation is not controlled in time, the scalp will continue to be destroyed and the stratum corneum will become significantly thinner.
For old people with dandruff, scalp cells average less than 10 layers, while healthy people have 25 to 35 layers of scalp cells. Apparently, the scalp's defensive barrier is severely weakened [7,8].
(Source: self-drawn)
Malassezia in the process of "gluttony" head oil, will "pull" out some "volatile organic compounds (VOCs)". When measured in large quantities, it emits an unpleasant odor.[9]
Even more frightening is hair loss! In people with hair loss, the proportion of malassezia infection is significantly higher [10].
Malassezia multiplyes in large numbers within the hair follicle and breaks down the oils in the hair follicle area into free fatty acids. Free fatty acids repeatedly irritate the hair follicles, eventually causing the follicles to dilate and rupture, and the contents are released into the surrounding tissues to create an inflammatory response. Hair follicles will also be destroyed one by one, resulting in hair loss!
(Source: self-drawn)
Although hair loss is related to many factors, such as heredity, age, sex hormone levels, nutrient intake of hair, mental state, etc.[11], the loss of scalp "species" and the destruction of "ecosystems" can still make your hair ruthlessly abandon you.
There are also hair follicle stem cells responsible for regeneration in the hair follicle, and if they are also attacked, they will be replaced by scars, forming "scar alopecia". This alopecia is irreversible, i.e. permanent.[12]
1. Eat less spicy and irritating foods and do not drink alcohol [13-15].
2. Don't scratch your head when it's okay.
Image source: Stand Cool Helo
3. Pay attention to rest, do not stay up late.
4. Wash your hair frequently and choose a shampoo that inhibits fungus, such as ketoconazole lotion.
5. Replace the pillowcase 1 to 2 times a week.
If the situation is serious, full of rashes or pustules, pus, exudate, scalp itching, pain symptoms, affecting work or even sleep, do not hesitate, hurry to the dermatologist!
Image source: Stand Cool Helo
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Contributing Author: Gong Long | Doctor of Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College
bibliography
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Lei Wanjun, Dai Tao. Dermatology[M]. People's Military Medical Publishing House, 2011.
[3] Malassezia species in healthy skin and in dermatological conditions. Prohic A, Jovovic Sadikovic T, Krupalija-Fazlic M, Kuskunovic-Vlahovljak S. Int J Dermatol. 2016 May;55(5):494-504.
[4] Malassezia ecology, pathophysiology, and treatment. Theelen B, Cafarchia C, Gaitanis G, Bassukas ID, Boekhout T, Dawson TL Jr. Med Mycol. 2018 Apr 1;56(suppl_1):S10-S25.
[5] C. W. Saunders, A. Scheynius, J. Heitman, 《Malassezia fungi are specialized to live on skin and associated with dandruff, eczema, and other skin diseases》, PLoS Pathog., 卷 8, 期 6, 页 e1002701, 2012, doi: 10.1371/journal.ppat.1002701.
[6] J. W. Lee, B. J. Kim 和 M. N. Kim, 《Photodynamic therapy: new treatment for recalcitrant Malassezia folliculitis》, Lasers Surg. Med., 卷 42, 期 2, 页 192–196, 2 月 2010, doi: 10.1002/lsm.20857.
Lu Yonghong, Ran Yuping. Malassezia and dandruff[J]. Journal of Dermatological and Venereal Disease Diagnosis and Treatment, 2001, 008(004):267-268,263.
[8] Kerr K, Darcy T, Henry J, Mizoguchi H, Schwartz JR, Morrall S, Filloon T, Wimalasena R, Fadayel G, Mills KJ. Epidermal changes associated with symptomatic resolution of dandruff: biomarkers of scalp health. Int J Dermatol. 2011 Jan;50(1):102-13.
[9] Gonzalez M, Celis AM, Guevara-Suarez MI, Molina J, Carazzone C. Yeast Smell Like What They Eat: Analysis of Volatile Organic Compounds of Malassezia furfur in Growth Media Supplemented with Different Lipids.Molecules. 2019 Jan 24;24(3):419.
[10] Nematian J, Ravaghi M, Gholamrezanezhad A, Nematian E.Increased hair shedding may be associated with the presence of Pityrosporum ovale. Am J Clin Dermatol. 2006;7(4):263-6.
[11] Al Aboud AM, Zito PM. Alopecia.2020 Sep 29. In: StatPearls [Internet].
Qi Shiling, Zhao Ying, Zhang Xiaoting, et al. Clinical and pathological characteristics of 53 cases of scarring alopecia[J]. Chin J Dermatology, 2013, 46(010):731-735.
Zhang H, Chao H An, Wu Chipeng, et al. Risk factors for sebum-related diseases in adolescents and their correlation with gastrointestinal diseases[J]. Chinese Journal of Dermatology, 2006, 39(2):102-104.
Li Junfeng, Ma Junping, Liu Jie, et al. Keloid folliculitis of Xiangbu[J]. Chinese Journal of Dermatology and Venereology, 2011(11):60.
[15] Anon. Epidemiological study of malassezia infection-related diseases in Changchun area[J]. Chinese Journal of Endemic Disease Prevention and Control (Issue 5): 492-493.
*The content of this article is a popularization of health knowledge and cannot be used as a specific diagnosis and treatment recommendation, nor is it a substitute for face-to-face consultation by a practicing physician, for reference only.
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