Skin lesions and infectious diseases of the integumentary system

Infections

Infections of the integumentary system can be caused by many different pathogens. When working with patients in this specialty, it is important to have an understanding of the different types of infections. These infections are discussed in the following sections.

Bacterial infections

When working in dermatology, a medical assistant should be familiar with the common bacterial infections that are found in the integumentary system. The following sections discuss those bacterial infections.

Impetigo

Impetigo is a common, superficial infection caused by Streptococcus sp. or Staphylococcus aureus that usually affects children. Initially, impetigo looks like small vesicles on the face (especially around the nose and mouth) that quickly enlarge and rupture, excreting a honey-colored exudate. The exudate forms crusty lesions, and beneath the crust, the area is inflamed and moist. Pruritus accompanies the infection, and scratching helps spread the lesions at the site. Impetigo is contagious, and bacteria are transmitted by direct contact with the drainage, whether this occurs at other sites or with other children through the sharing of toys and physical contact. Consistent handwashing is required to help break the chain of infection. It is also important to keep personal items that may be contaminated, such as washcloths, linens, and drinking glasses, away from other members of the family. If the areas of infection are limited, topical treatment with an antibiotic ointment may be effective. However, impetigo caused by streptococci may result in glomerulonephritis; more involved infections may require treatment with oral antibiotics.

Acne vulgaris

Acne vulgaris is a skin condition that occurs when a hair follicle becomes plugged with oil and dead skin cells. Acne is most common on the face, but it can occur on other sites of the body, such as the neck, chest, shoulders, and back. Acne is most common during adolescence, but it can occur at any age. Because acne can cause scarring, it is best treated as early as possible to minimize scars and emotional distress. The main causes of acne include excess oil production, pores clogged with dead skin cells and oil, and bacterial infections. Once a pore is clogged, bacteria trapped in the pore multiply and cause inflammation. Risk factors for acne include age (adolescents are most prone due to hormonal changes), medications (corticosteroids, androgens, oral contraceptives, and lithium), stress, and diet (a diet that is high in dairy products and simple carbohydrates, such as refined sugars, processed foods, and sweets, can make acne worse). The signs and symptoms of acne can vary in severity. Common symptoms include the following:

• Whiteheads and blackheads
• Papules and pustules
• Large, solid, painful nodules
• Painful, pus-filled lumps beneath the skin’s surface, known as cystic acne There are many treatments used for acne, from simple over-the-counter (OTC) lotions to more extensive use of medications, antibiotics, and dermatologic procedures:
• Common medications include topical prescription-strength benzoyl peroxide, antibiotics, retinoids, and oral contraceptives.
• Common dermatologic procedures include light therapy, chemical peels, extraction of whiteheads and blackheads by a provider, and steroid injections.
• Common dietary changes recommended include reducing or eliminating dairy products, refined sugar, and simple carbohydrate foods. Examples include juice, soda, sweets, pasta, and bread.
• More extensive treatments include dermabrasion, laser resurfacing, and minor skin surgery to repair areas of damage or excessive scarring. Acne often requires extended treatment and follow-up, depending on the severity of the condition.

Rosacea

Rosacea is a chronic disease seen most frequently in women between the ages of 30 and 60. It causes inflammation and pustule formation and begins as frequent flushing across the nose, forehead, cheeks, and chin. As the condition progresses, capillaries of the face dilate and are visible across affected areas as small, red, edematous lines; these are accompanied by eye inflammation and photosensitivity. Over time, the face appears red, eye inflammation is more apparent, and painful nodules and pustules form. Men with rosacea may develop rhinophyma, a large, inflamed, bulbous nose caused by hyperplasia of sebaceous nasal tissue. Individuals with rosacea eventually may develop an obvious thickening of the skin across the forehead, nose, cheeks, and chin. The condition is treated with topical antibiotics and, as symptoms progress, with oral antibiotics, such as doxycycline (Oracea), which helps reduce the number of pimples and bumps on the face; however, it may not reduce the redness and flushing.

Furuncles and Carbuncles

A furuncle, or boil, is a localized staphylococcal infection that begins as inflammation of a hair follicle (folliculitis) or skin gland. The affected area is raised, inflamed, and painful and eventually may produce purulent drainage. A carbuncle is a collection of furuncles that have joined to form a large, infected area that may drain through multiple sites or form an abscess. Both infections are treated with oral antibiotics, frequent cleansing of the area, application of an antibiotic ointment and, in some cases, surgical incision and drainage of the purulent material.

Cellulitis

Cellulitis is an acute infection of the skin and subcutaneous tissue caused by staphylococci or streptococci. It begins from a small cut or as a result of a skin injury or develops at the site of a furuncle or an ulcer. The area surrounding the site becomes inflamed, edematous, and painful, with red streaks along the lymph vessels that lead from the infection. The condition is treated with oral antibiotics. Warm compresses applied locally aid healing, and analgesics may be needed to relieve discomfort. It is important that patients with cellulitis are treated appropriately because a systemic infection can develop if the lymph glands become involved.