Integumentary Flashcards
Sun Damage
Melanin synthesis peaks about 10 days after initial sun exposure, which is why pale-skinned individuals tend to suffer sunburns of the epidermis initially. Dark-skinned individuals can also get sunburns but are more protected than are pale-skinned individuals. Too much sun exposure can eventually lead to wrinkling due to the destruction of the cellular structure of the skin, and in severe cases, can cause sufficient DNA damage to result in skin cancer. When there is an irregular accumulation of melanocytes in the skin, freckles appear. Moles are larger masses of melanocytes, and although most are benign, they should be monitored for changes that might indicate the presence of cancer
Basal Cell Carcinoma
Basal cell carcinoma is a form of cancer that affects the mitotically active stem cells in the stratum basale of the epidermis. It is the most common of all cancers that occur in the United States and is frequently found on the head, neck, arms, and back, which are the most susceptible to long-term sun exposure. Although UV rays are the main culprit, exposure to other agents, such as radiation and arsenic, can also lead to this type of cancer. Wounds on the skin due to open sores, tattoos, burns, et cetera may be predisposing factors. Basal cell carcinomas start in the stratum basale and usually spread along this boundary. At some point, they begin to grow toward the surface and become an uneven patch, bump, growth, or scar on the skin surface (see Figure 5.11). Like most cancers, basal cell carcinomas respond best to treatment when caught early. Treatment options include surgery, freezing (cryosurgery), and topical ointments.
Squamous Cell Carcinoma
cancer that affects the keratinocytes of the stratum spinosum and presents as lesions commonly found on the scalp, ears, and hands (see Figure 5.12). It is the second most common skin cancer. The American Cancer Society reports that two of 10 skin cancers are squamous cell carcinomas, and it is more aggressive than basal cell carcinoma. If not removed, these carcinomas can metastasize. Surgery and radiation are used to cure squamous cell carcinoma.
Melanoma
cancer characterized by the uncontrolled growth of melanocytes, the pigment-producing cells in the epidermis. Typically, a melanoma develops from a mole. It is the most fatal of all skin cancers, as it is highly metastatic and can be difficult to detect before it has spread to other organs. Melanomas usually appear as asymmetrical brown and black patches with uneven borders and a raised surface (see Figure 5.13). Treatment typically involves surgical excision and immunotherapy.
ABCDE for Melanoma Diagnosis
Doctors often give their patients the following ABCDE mnemonic to help with the diagnosis of early-stage melanoma. If you observe a mole on your body displaying these signs, consult a doctor:
• Asymmetry: the two sides are not symmetrical
• Borders: the edges are irregular in shape
• Color: the color is varied shades of brown or black
• Diameter: it is larger than 6 mm (0.24 in)
• Evolving: its shape has changed
Some specialists cite the following additional signs for the most serious form, nodular melanoma:
• Elevated: it is raised on the skin surface
• Firm: it feels hard to the touch
• Growing: it is getting larger
Albinism
a genetic disorder that affects (completely or partially) the coloring of skin, hair, and eyes. This is primarily due to the inability of melanocytes to produce melanin. Individuals with albinism tend to appear white or very pale due to the lack of melanin in their skin and hair. Recall that melanin helps protect the skin from the harmful effects of UV radiation. Individuals with albinism tend to need more protection from UV radiation, as they are more prone to sunburns and skin cancer. They also tend to be more sensitive to light and have vision problems due to the lack of pigmentation on the retinal wall.
Treatment of this disorder usually involves addressing the symptoms, such as limiting UV light exposure to the skin and eyes.
Vitiligo
the melanocytes in certain areas lose their ability to produce melanin, possibly due to an autoimmune reaction. This leads to a loss of color in patches (see Figure 5.14). Neither albinism nor vitiligo directly affects the lifespan of an individual.
Jaundice
Liver disease or liver cancer can cause the accumulation of bile and the yellow pigment bilirubin, leading to the skin appearing yellow or jaundiced.
Darkening of the skin
Tumors of the pituitary gland can result in the secretion of large amounts of melanocyte-stimulating hormone (MSH), which results in a darkening of the skin.
Deep bronze coloration of the skin
Addison’s disease can stimulate the release of excess amounts of adrenocorticotropic hormone (ACTH), which can give the skin a deep bronze color
Ashen skin coloration
A sudden drop in oxygenation can affect skin color, causing the skin to initially turn ashen (white).
Cyanosis
After a prolonged reduction in oxygen levels, dark red deoxyhemoglobin becomes dominant in the blood, making
the skin appear blue, a condition referred to as cyanosis. This happens when the oxygen supply is restricted, as when someone is experiencing difficulty in breathing because of asthma or a heart attack. However, in these cases, the effect on skin color has nothing to do with the skin’s pigmentation.
Eczema
an allergic reaction that manifests as dry, itchy patches of skin that resemble rashes (see Figure 5.15). It may be accompanied by swelling of the skin, flaking, and in severe cases, bleeding. Symptoms are usually managed with moisturizers, corticosteroid creams, and immunosuppressants.
Acne
a skin disturbance that typically occurs on areas of the skin that are rich in sebaceous glands (face and back). It is most common along with the onset of puberty due to associated hormonal changes, but can also occur in infants and continue into adulthood. Hormones, such as androgens, stimulate the release of sebum. Overproduction and accumulation of sebum along with keratin can block hair follicles. This plug is initially white. The sebum, when oxidized by exposure to air, turns black. Acne results from infection by acne-causing bacteria (Propionibacterium and Staphylococcus), which can lead to redness and potential scarring due to the natural wound healing process
Ringworm (what it is and what are the different location names)
Tinea or dermatophytosis is often referred to as ringworm. Ringworm presents as a circular rash that is itchy and red
and
• • • • • •
can be found on various parts of the body. It is referred to by the location that it is found:
Tinea pedis – feet (commonly referred to as athlete’s feet) Tinea capitis – scalp
Tinea barbae – beard
Tinea manuum – hands
Tinea unguium – toenails and fingernails (also called onychomycosis)
Tinea corporis – body parts such as arms and legs (Center for Disease Control and Prevention, n.d.-a)
Psoriasis
a chronic autoimmune disorder that results in patches of thick red skin with the appearance of silvery scales. These patches can be found on elbows, knees, scalp, low back, face, feet, fingernails, toenails, and even the mouth. Psoriasis can be confused with other skin diseases, so a dermatologist is the best physician to diagnose psoriasis. Treatments may include creams, ointments, ultraviolet light therapy, and medication
Skin Injury Healing Process
• The first step to repairing damaged skin is the formation of a blood clot that helps stop the flow of blood and scabs over time. Many different types of cells are involved in wound repair, especially if the surface area that needs repair is extensive.
• Before the basal stem cells of the stratum basale can recreate the epidermis, fibroblasts mobilize and divide rapidly to repair the damaged tissue by collagen deposition, forming granulation tissue.
• Blood capillaries follow the fibroblasts and help increase blood circulation and oxygen supply to the area.
• Immune cells, such as macrophages, roam the area and engulf any foreign matter to reduce the chance of
infection.
Rule of Nines (Burn)
Head and Neck 9%
Upper limbs 9%
Trunk 36%
Genitalia 1%
Lower limbs 18%
First degree burn
a superficial burn that affects only the epidermis. Although the skin may be painful and swollen, these burns typically heal on their own within a few days. Mild sunburn fits into the category of a first- degree burn.
Second degree burn
deeper and affects both the epidermis and a portion of the dermis. These burns result in swelling and a painful blistering of the skin. It is important to keep the burn site clean and sterile to prevent infection. If this is done, the burn will heal within several weeks.
Third degree burn
fully extends into the epidermis and dermis, destroying the tissue and affecting the nerve endings and sensory function. These are serious burns that may appear white, red, or black; they require medical attention and will heal slowly without it.
Fourth degree burn
burn is even more severe, affecting the underlying muscle and bone.
Oddly, third and fourth-degree burns are usually not as painful because the nerve endings themselves are damaged. Full-thickness burns cannot be repaired by the body, because the local tissues used for repair are damaged and require debridement, or amputation in severe cases, followed by grafting of the skin from an unaffected part of the body, or from skin grown in tissue culture for grafting purposes. Skin grafts are required when the damage from trauma or infection cannot be closed with sutures or staples.
Keloid
an overproduction of scar tissue, because the process of collagen formation does not stop when the wound is healed; this results in a keloid.
Atrophic scars
In contrast, scars that result from acne and chickenpox have a sunken appearance and are called atrophic scars.
Bedsores/Decubitus Ulcers
Skin and its underlying tissue can be affected by excessive pressure. One example of this is called a bedsore. Bedsores, also called decubitus ulcers, are caused by constant, long-term, unrelieved pressure on certain body parts that are bony, reducing blood flow to the area and leading to necrosis. Bedsores are most common in elderly patients who have debilitating conditions that cause them to be immobile. Most hospitals and long-term care facilities have the practice of turning the patients every few hours to prevent the incidence of bedsores. If left untreated, bedsores can be fatal if they become infected.
Corn
a specialized form of callus. Corns form from abrasions on the skin that result from an elliptical-type motion.
