INTRODUCTION

Post edited by Ariel Acurio 



The integumentary system is an organ system consisting of the skin, hair, nails, and exocrine glands. The skin is only a few millimeters thick yet is by far the largest organ in the body. The average person’s skin weighs 10 pounds and has a surface area of almost 20 square feet. Skin forms the body’s outer covering and forms a barrier to protect the body from chemicals, disease, UV light, and physical damage. Hair and nails extend from the skin to reinforce the skin and protect it from environmental damage. The exocrine glands of the integumentary system produce sweat, oil, and wax to cool, protect, and moisturize the skin’s surface.

Anatomy of the Integumentary System

Epidermis 

The epidermis is the most superficial layer of the skin that covers almost the entire body surface. The epidermis rests upon and protects the deeper and thicker dermis layer of the skin. Structurally, the epidermis is only about a tenth of a millimeter thick but is made of 40 to 50 rows of stacked squamous epithelial cells. The epidermis is an avascular region of the body, meaning that it does not contain any blood or blood vessels. The cells of the epidermis receive all of their nutrients via diffusion of fluids from the dermis

Dermis 

The dermis is the deep layer of the skin found under the epidermis. The dermis is mostly made of dense irregular connective tissue along with nervous tissue, blood, and blood vessels. The dermis is much thicker than the epidermis and gives the skin its strength and elasticity. Within the dermis there are two distinct regions:  the papillary layer and the reticular layer.

The papillary layer is the superficial layer of the dermis that borders on the epidermis. The papillary layer contains many finger-like extensions called dermal papillae that protrude superficially towards the epidermis. The dermal papillae increase the surface area of the dermis and contain many nerves and blood vessels that are projected toward the surface of the skin. Blood flowing through the dermal papillae provide nutrients and oxygen for the cells of the epidermis. 


Hypodermis 

Deep to the dermis is a layer of loose connective tissues known as the hypodermis, subcutis, or subcutaneous tissue. The hypodermis serves as the flexible connection between the skin and the underlying muscles and bones as well as a fat storage area.  Areolar connective tissue in the hypodermis contains elastin and collagen fibers loosely arranged to allow the skin to stretch and move independently of its underlying structures. Fatty adipose tissue in the hypodermis stores energy in the form of triglycerides. Adipose also helps to insulate the body by trapping body heat produced by the underlying muscles


Hair 

Hair is an accessory organ of the skin made of columns of tightly packed dead keratinocytes found in most regions of the body. The few hairless parts of the body include the palmar surface of the hands, plantar surface of the feet. Hair helps to protect the body from UV radiation by preventing sunlight from striking the skin.  Hair also insulates the body by trapping warm air around the skin.

The structure of hair can be broken down into 3 major parts: the follicle, root, and shaft. The hair follicle is a depression of epidermal cells deep into the dermis. Stem cells in the follicle reproduce to form the keratinocytes that eventually form the hair while melanocytes produce pigment that gives the hair its color. Within the follicle is the hair root, the portion of the hair below the skin’s surface. As the follicle produces new hair, the cells in the root push up to the surface until they exit the skin. The hair shaft consists of the part of the hair that is found outside of the skin.

The hair shaft and root are made of 3 distinct layers of cells: the cuticle, cortex, and medulla. The cuticle is the outermost layer made of keratinocytes. The keratinocytes of the cuticle are stacked on top of each other like shingles so that the outer tip of each cell points away from the body. Under the cuticle are the cells of the cortex that form the majority of the hair’s width. The spindle-shaped and tightly packed cortex cells contain pigments that give the hair its color. The innermost layer of the hair, the medulla, is not present in all hairs. When present, the medulla usually contains highly pigmented cells full of keratin. When the medulla is absent, the cortex continues through the middle of the hair.

Nails

Nails are accessory organs of the skin made of sheets of hardened keratinocytes and found on the distal ends of the fingers and toes. Fingernails and toenails reinforce and protect the end of the digits and are used for scraping and manipulating small objects. There are 3 main parts of a nail: the root, body, and free edge. The nail root is the portion of the nail found under the surface of the skin. The nail body  is the visible external portion of the nail. The free edge is the distal end portion of the nail that has grown beyond the end of the finger or toe.

Nails grow from a deep layer of epidermal tissue known as the nail matrix, which surrounds the nail root. The stem cells of the nail matrix reproduce to form keratinocytes, which in turn produce keratin protein and pack into tough sheets of hardened cells. The sheets of keratinocytes form the hard nail root that slowly grows out of the skin and forms the nail body as it reaches the skin’s surface. The cells of the nail root and nail body are pushed toward the distal end of the finger or toe by new cells being formed in the nail matrix.

Diseases of the integumentary system 

Dermatologists specialize in treating diseases, disorders and injuries of the skin, hair and nails. They treat common conditions such as acne and warts; chronic skin conditions such as eczema and psoriasis; and more serious diseases like skin cancer, according to the AAD. A residency in dermatology involves one year as an intern in either surgery or internal medicine, followed by a three-year residency.

After this, many dermatologists pursue further training through one- or two-year fellowships in specialized fields, such as cosmetic surgery, laser medicine or immunodermatology, the AAD noted. 

Skin cancer 

There are three main types of skin cancer, the most common of which is basal cell carcinoma, said Dr. Charles E. Crutchfield III, a clinical professor of dermatology .More than 2 million cases of this skin cancer are diagnosed in the United States every year, according to the AAD. This type of cancer is skin colored or has a slight pearl color to it. It rarely metastasizes (i.e., it rarely spreads to other parts of the body), but it can be very problematic if it's not treated, Crutchfield cautioned. According to the AAD, basal cell carcinoma can destroy skin tissue and bone.

The second most common skin cancer is squamous cell carcinoma. This is a rough-surfaced skin-colored lesion. Squamous cell skin cancer causes death in about 10 percent of affected patients.  

The most serious skin cancer is melanoma, which looks like a dark, changing, bleeding skin spot, Crutchfield said. Melanoma is fatal in as many as 35 percent of patients diagnosed with this form of skin cancer.

Warts

Warts
Warts are rough bumps caused by a viral infection. They commonly occur on the hands and feet. Sometimes, tiny black dots will be visible in a wart, Crutchfield noted. "Those are blocked blood vessels, which is a common occurrence with a papilloma viral infection." The best treatment for warts is to cause a mild irritation of the wart — usually by freezing, liquid irritation and lasers — so the immune system can recognize the viral infection and get rid of it. 

Eczema

Eczema are little points that appears in your skin due to many reasons. 
Also known as dermatitis, eczema looks like red, itchy, flaky skin. It can occur anywhere. Sometimes, it happens by itself, and other times, it is caused by outside factors such as poison ivy, according to Crutchfield. Dermatitis is best treated with topical anti-inflammatory creams and ointments. For mild cases, over-the-counter medications work well, but a prescription may be required for more severe cases.

Treatment of atopic dermatitis is typically with moisturizers and steroid creams.The steroid creams should generally be of mid- to high strength and used for less than two weeks at a time as side effects can occur. Antibiotics may be required if there are signs of skin infection. Contact dermatitis is typically treated by avoiding the allergen or irritant. Antihistamines may help with sleep and to decrease nighttime scratching.

Dermatitis was estimated to affect 245 million people globally in 2015Atopic dermatitis is the most common type and generally starts in childhood.In the United States it affects about 10-30% of people. Contact dermatitis is twice as common in females than males. Allergic contact dermatitis affects about 7% of people at some point in time.Irritant contact dermatitis is common, especially among people who do certain jobs; exact rates are unclear.

Acne 

Acne, probably you are experiencing this problem in the adolescence. Dont worry ,is a disorder of the hair and oil glands, is among the most common conditions treated by dermatologists, Crutchfield said. "It is under the control of hormonal changes, hence the initial flare during adolescence," he said.

Popping a pimple should not be done by anyone but a qualified dermatologist. Pimple popping irritates skin, can make the bacteria spread, and can cause scars. If you must pop a pimple yourself, it is advised to apply warm water to the area before popping it and to wash your hand thoroughly before beginning so as to avoid spreading bacteria via the hands. Applying hot water will open up the pores and reduce the damage because it will require less force to pop it.

Acne presents itself as red bumps and pimples on the face, chest and back, Crutchfield said. Treatments include vitamin A products (retinols), salicylic acid (to unplug pores), benzoyl peroxides (to decrease bacteria) and antibiotics (to reduce inflammation).
There is nothing to care about this, with water and good alimentation the problem will dissapear.

Vitiligo 

Vitiligo is a condition in which the cells that produce skin color — melanocytes — no longer function properly. Some are attacked by the immune system. Sometimes, the cells mysteriously die or stop working, Crutchfield noted. "When this happens, the person with vitiligo can get multiple patches of white skin. One of the best treatments for vitiligo is specialized light treatment from a doctor."

OTHER COMMON PROBLEMS 

Psoriasis 

Psoriasis is an inflammatory skin condition in which red, itchy plaques commonly occur on the knees and elbows. Crutchfield explained that the nails can have pits and the scalp can be red and itchy, flaky and inflamed. "About 3 percent of all people have psoriasis to some degree, and it does run in families many times," he noted. Some patients with psoriasis can also develop arthritis, called psoriatic arthritis. The best treatment for psoriasis are topical medicines, light treatments and, in severe cases, systemic prescription medicines.

Moles 

Moles are normal parts of the skin. Moles can be flat or raised, and they can be red, brown, black or skin-colored. If a mole start changing — in size, color or shape, or if it bleeds and doesn't heal on its own in three weeks — it should be evaluated by a doctor to make sure it is not turning into a skin cancer, .

The nutrition is important to help the intergumentary system. Theres a fact that says that the 80 % of adolescents suffers acne because of the bad nutrition. The bad nutrition is comon on the kids, thats why we need start to change. here we give you some tips to mejorate your nutrition: 

Eat a variety of foods 

Base your diet on foods rich in carbohydrates

Take lots of fruits and vegetables

Maintain a healthy body weight and feel good

Eat moderate rations: reduce, do not eliminate food

Eat regularly

Drink plenty of fluids 

Move