Ib

PRIM AKY I.ESION 1 Hifí NITION

Vc.vfV

l'<i[viiif ih.ii i'nttains vl< Ji thi'.l; a biistM >

Ueijvs >im¡>k-x . :.I lirijn':- ''(«iii:■',: : D;.si)!il|.>ln eivi-uu O :iiUKI .k ntuuu, ■

1'UsUllt"

:J.01 ,Ui/c>l Huh; colic« ts-M: '> ur. ia liur.i'U r; ■.■:■ I n;,!r \v;i,:!c

I'.ipuii lh.il i "iiOms p'.n lilrul ni.il' Tia!

Nodule that n.muir.s fluid or M. nuvilid .'»¡.lli ri.il

:J.01 ,Ui/c>l Huh; colic« ts-M: '> ur. ia liur.i'U r; ■.■:■ I n;,!r \v;i,:!c

Nodule that n.muir.s fluid or M. nuvilid .'»¡.lli ri.il

IVjii|ihi;;:us vuHyvis Kiitloti-. |i'.nipii¡;¿. .id ]!.ulh >ti-. iaipecigtv.

hpiiV-roMwi i.p;

Vitiligo: depigmentation of unknown etiology; associated with pernicious anemia, hypothyroidism, Addison's disease, and diabetic mcllitus; may have autoimmune basis. Patients often have antibodies to melanin, parietal cells, or thyroid.

Pruritus: may be a clue to diagnosis of serious and common conditions; seen in obstructive biliary disease, uremia, polycythemia rubra vera (classically after a warm shower or bath), contact or atopic dermatitis, scabies, and lichen planus.

Contact dermatitis: often due to a ty pe IV hypersensitivity reaction; also may be due to irritating or toxic substance. Look for question that mentions new exposure to a classic offending agent (poison ivy, nickel earrings, deodorant).The rash is well circumscribed and found only in the area of exposure; skin is red and itchy and often has vesicles or bullae. Avoidance of the agent is required; patch testing can be done, if needed, to determine the antigen.

Atopic, dermatitis: look for family and personal history of allergies (e.g., hay fever) and asthma. This chronic condition begins in the first year of life with red, itchy, weeping skin on the head, upper extremities, and sometimes around the diaper area.The biggest problem is scratching, which leads to skin breaks and possible bacterial infection. Treatment involves avoidance of drying soaps, antihistamines, and topical steroids (see figure, top of next page).

Seborrheic dermatitis: causes the common conditions known as cradle cap and dandruff as well as blepharitis (eyelid inflammation). Look for scaling skin on the scalp and eyelids, and treat with, dandruff shampoo.

Fungal skin infections (dermatophyte infections, ringworm), depending on location, are known as:

1. Tinea corporis (body/trunk): look for red ring-shaped lesions that have raised, borders and tend to clear centrally while they expand peripherally.

Phases of atopic dermatitis. A, Infantiie phase. Typica! erythematous, oozing, and crusted plaques seen on the cheek of an infant with atopic dermatitis, B, Childhood phase. Closo-up viow of a lichenified, excoriated, crusted, and secondarily infected pfaque on the right knee of a 4-year-old girl. C, Adolescent or young adult phase. (From Ftapatrick JE, Aeling JL: Dermatology Secrete. Philadelphia, Hanley & Belfus, 1996, with permission.)

1. Tinea pedis (athlete's foot): look for macerated, scaling web spaces between the toes that often itch and thickened, distorted toenails (onychomycosis). Good foot hygiene h part of treatment.

3. Tinea unguium (onychomycosis): thickened, distorted nails with debris under the nail edges.

4. Tinea capitis (scalp): mainly affects children (highly contagious), who have scaly patches of hair loss and may have an inflamed, boggy granuloma of the scalp (known as a kerion), which usually resolves on its own.

SL Tinea cruris (jock itch): more common in obese males, usually in the crural folds of the upper inner thighs.

Most fungal skin infections are due to Trichophyton species. Infections are diagnosed by scrap ing the lesion and doing a potassium hydroxide (KOH) preparation to visualize the fungus or a culture. Griseofulvin (oral) must be used to treat tinea capitis and onychomycosis; the others can be treated with topical antifungals (e.g., miconazole, clotrimazole, ketoconazole) or griseofulvin, which is better for severe or persistent infectious, In tinea capitis, if the; hair fluoresces underWood's lamp, Microsporum sp. is the cause; if it does not, the probable cause is Trichophyton sp.

Candidiasis: thrush (creamy white patches on the tongue or buccal mucosa that can be scraped off) may be seen in normal children, and candidal vulvovaginitis is seen in normal women, especially when they are pregnant or after taking antibiotics. However, at other times and in different patients, candidal infections may be a sign of diabetes meliitus or immunodeficiency. For example, thrush in an adult male should make you think about the possibility of HIV/AIDS. Treat with local or topical nystatin or imidazoles (e.g., miconazole, clotrimazole); oral therapy (nystatin or ketoconazole) is used for extensive or resistant disease,

Tinea versicolor: Pityrosporon sp. infection that presents most commonly in young adults with multiple patches of various size and color (brown, tan, and whi te) on the torso. It often becomes noticeable in the summer because the affected areas fail to tan and look white. Diagnose from lesion scrapings (KOH preparation). Treat with selenium sulfide shampoo or topical imidazoles.

Tinea versicolor demonstrating hypopigmented scaly papules, (horn Rtzpatrick Jk, Aeling JL: Darmatology Secrets. Philadelphia, Hanley & Belfus, 1996, with permission.)

Scabies: caused by the mite Stncopies scabei, which tunnels into the skin and leaves visible bur rows on the skin (know what they look like), classically in the linger web spaces and flexor surface of the wrists. Facial involvement sometimes is seen in i nfants. Patients have severe pru ritus, and itching may lead to secondary bacterial infection. Diagnosis is made by scraping the mite out of a burrow and viewing it under a microscope. Treat with permethrin cream applied to the whole body. Remember to treat all contacts (e.g., the whole family). Do not use lindane to treat unless permethrin is not a choice. Lindane used to be the treatment of choice but can cause neurotoxicity, especially in young children.

Lice (pediculosis): lice can infect the head (Peciiculus capitis, which is common in school aged children), body (Pdictilus corporis, which is unusual in people with good hygiene), or pubic area (crabs, caused by Phthirus pubis and transmitted sexually). Infected areas tend to itch, and diag nosis is made by seeing the lice on hair shafts. Treat with permethrin ire am (preferred over lindane because of lindanes neurotoxicity), and decontaminate sources of reinfection (wash or sterilize combs, hats, bed sheets, clothing).

Warts: caused by human papillomavirus (HPV); infections are most commonly seen in older children, often on the hands. Treatments include salicylic: acid, liquid nitrogen, curettage, and others. Genital warts also are caused by HPV (types 1 6 and 18 are associated with cervical cancer). (See figure, top of next page. )

Molhist'um cont agios urn: a poxvirus infection that is common in children but also may be transmitted sexually. A child who has genital molluseum may or may not have contracted the infection from sexual contact; auto'truioaiiatiori is possible. Do not automatically assume child abuse, although it must be ruled out. Diagnosis is made by the characteristic appearance of the lesions (skincolored, smooth, waxy papules with a central depression [umbilicatedj that are roughly O. S cm) or by looking at contents of the lesion, which include cells with characteristic inclusion bodies. Usually treated with freezing or curettage.

Same common types of warts. A, Rat warts of the face. B, Wart of the hand. (From Fitzpatrick JE, AfiJing JL: Dermatology Secrets. Philadelphia, Hanley & Belfiis, IflEtB, with permission.)

Acne: know the description of acne: comedones (whiteheads, blackheads), papules, pustules, inflamed nodules, superficial pus-filled cysts with possible inflammatory skin changes. Propionilwctcrium acnes is thought to be partially involved i n pathogenesis as well as blockage of pi-losebaceous glands. Acne has not been proved to be related to food (but if the patient relates it to a food, you can try discontinuing it), exercise, or sex/masturbation, but cosmetics may aggravate it. Treatment options are multiple. Start with topical benzoyl peroxide, then try topical clindamycin, oral tetracycline, oral erythromycin (for P. acnes eradication), and topical tretinoin.The last resort is oral isotretinoin. Isotretinoin is highly effective but teratogenic (pregnancy testing before and during therapy is mandatory) and may cause dry skin and mucosae, muscle and joint pain, and liver function abnormalities.

Rosacea: looks like acne but starts in middle age. Look for rhinophyma (bulbous red nose) and coexisting blepharitis.Treat with topical metronidazole or oral tetracycline.The pathogenesis is unknown, but it is not related to diet.

Hirsutism: most commonly idiopathic, but other signs of virilization (deepening voice, clitoromegaly, frontal balding) indicate an androgen-secreting ovarian minor. Other causes include corticosteroid administration, Gushing s syndrome, Stein-Leventhal syndrome (polycystic ovary), and, drugs (minoxidil and phenytoin).

Baldness: watch out for trichotillomania (psychiatric patients pulling out their hair) and alopecia areata (idiopathic and associated with antimicrosomal and other autoantibodies, lupus, syphilis, or chemotherapy) as exotic causes of irregular, patchy baldness. Male-pattern baldness is considered a genetic disorder that requires androgens to be expressed.

Psoriasis: know what classic lesions look like and how they are described (dry, not pruritic, well-circumscribed, silvery, scaling papules and plaques). 'Family history is often positive. Psoriasis occurs mostly in whites with onset in early adulthood. Classic lesions are found on the scalp and extensor surfaces of the elbows and knees. Patients may have pitting of the nails and arthritis that resembles rheumatoid arthritis but is rheumatoid factor-negative. Diagnosis is made by appearance, but biopsy can be used for doubtful cases. Treatment is complex but involves exposure to ultraviolet light (e.g. sunlight), lubricants, topical corticosteroids, and keratolyses (coal tar, salicylic acid, anthralin). (See figure, top of next page.)

demonstrating typical well-demarcated, red plaques with silvery scale. (From Rtzpatrick JE, Aeling JL: Dermatology Secrets. Philadelphia, Hanley & Belfus, 1996, with permission.)

Pityriasis rosea; seems to lie a popular dermatology question. Pityriasis rosea is seen in adults. Look for a "herald patch" (slightly erythematous, ring-shaped or oval, and. scaly patch classically seen on the trunk.) followed 1 week later by many similar lesions that tend to itch. Look for lesions on the back with a long axis that parallels the Langerhans' skin cleavage lines, typically in a "Christmas tree" pattern. Pityriasis rosea usually remits spontaneously in I month. Think about syphilis in the differentia] diagnosis. Treat with reassurance.

Lichen planus: look for the four Ps (pruritic, purple, polygonal papules) and oral mucosal lesions.

Drug reactions: penicillin, cephalosporins, and sulfa drugs commonly cause rashes; tetracycline and phenothiazjnes commonly cause photosensitivity.

Erythema multiforme: look for classic target (iris) lesions. Usually caused by drugs or infections (e.g., herpes). The severe, form is known as Stevens Johnson syndrome, which often is fatal. Treat suppouivcly. (See figure below.)

A, Stevons-Jnhrison syndrome. Iypioal mucosal inflammation of the mouth, lips, and conjunctiva.

B, Erythema multiforme or Stevens-Johnson syndrome, the eruption consists of annular and papular erythema over the acral areas. (From Htzpatrick JE, Aelinçi JL: Dermatology Secrets. Philadelphia, Hanley & Belfus, 1H96, with permission.)

A, Stevons-Jnhrison syndrome. Iypioal mucosal inflammation of the mouth, lips, and conjunctiva.

B, Erythema multiforme or Stevens-Johnson syndrome, the eruption consists of annular and papular erythema over the acral areas. (From Htzpatrick JE, Aelinçi JL: Dermatology Secrets. Philadelphia, Hanley & Belfus, 1H96, with permission.)

Erythema nodosum: inflammation of the subcutaneous tissue and skin, classically over the shins (pretibial). Tender, red nodules are present. Look for exotic diseases such as sarcoidosis, coccidioidomycosis, and ulcerative colitis as the cause, although more commonly the cause is unknown or due to a streptococcal infection.

Pemphigus: an autoimmune disease of the middle aged and elderly that presents with multiple bullae, starting in the oral mucosa and spreading to the skin of the rest of the body. Biopsy can be stained for antibody and shows a linear immunofluorescence pattern. Treat with corticosteroids.

Dermatitis herpetiformis: should alert you to the presence of ghtten--sensitivity; look for diarrhea and weight loss. Skin lias IgA deposits even in unaffected areas. Patients present with intensely pruritic vesicles, papules, and wheals on the extensor aspects of the elbows and knees, possibly on the face and neck.Treat with gluten free diet.

Decubitus ulcers (bedsores or pressure sores): due to prolonged pressure against the skin. The best: treatment is prophylaxis. Periodic turning of paralyzed, bedridden, or debilitated patients prevents bedsores. Cleanliness and dryness also help to prevent tins condition, and periodic skin inspection makes sure that you catch the problem early. When missed, the lesions can ulcerate down to the bone and become infected, possibly leading to sepsis and death. Treat major skin breaks with aggressive surgical debridement and antibiotics if signs of infection are present.

Excessive perspiration: think of hyperthyroidism and pheochromocytoma.

Moles: common and benign, but malignant transformation is possible. Excisc any mole (or do a biopsy if the lesion is very large) if it enlarges suddenly, develops ir regu lar borders, darkens or becomes inflamed, changes color (even if only one small area of the mole changes color), begins to bleed, begins to itch, or becomes painful. Dysplastic nevus syndrome is a genetic condition with multiple dysplastic appearing nevi (usually > 100); also look for a family history of melanoma. Treat with careful follow-up and excision/biopsy of any suspicious-looking lesions as well as sun avoidance and sunscreen use.

Keratoacanthoma: mainly important because it mimics skin cancer (especially squamous cell cancer),This flesh colored lesion with a central crater contains keratinous material classically is found on the face. The best way to differentiate it from cancer is that a keratoacanthoma has a very rapid onset, and grows to full size in 1-2 months. Such rapid growth almost never occurs with squamous cell cancer. The lesion involutes spontaneously in a few months and requires no treatment. If you are unsure, the best option is a biopsy, but choose observation/keratoacanthoma if the history is classic.

Keloid: an overgrowth of scar tissue after an injury, most frequently seen in blacks. Usually slightly pink and classically found on the upper back, chest, and deltoid area. Also look for keloids to develop after ear piercing.

Basal cell cancer: begins as a shiny papule and slowly enlarges and develops an umbilicated center (which later may ulcerate) with peripheral telangiectasias. Basal cell cancer rarely metastasizes. As with all skin cancer, sunlight exposure increases risk. It is more common in light skinned people.Treat with excision. Biopsy any suspicious skin lesion in elderly patients.

Squamous cell cancer: look for preexisting actinic keratoses (hard, sharp, red, often scaly lesions in sun-exposed areas) or burn scars that become nodular, warty, or ulcerated. Do a biopsy if this happens! Squamous cell cancer in situ is known as Bowen's disease. (See figure, top of next page.)

Squamous cell carcinoma of the Gar, demonstrating a nodulo with central scale and crust. (From Ftopatrsck JE, Aeling JL: Dermatology Secrets. Philadelphia, Hanlfiy & Belfus, 1996, with permission.)

Malignant melanoma: usually arises from preexisting moles. Remember your ABCDs: asymmetry, irregular borders, color change, and increasing diameter). Prognosis is directly related to the depth of vertical invasion. Superficial spreading melanoma tends to stay superficial and has the best prognosis. Nodular melanoma is the worst because it tends to grow downward first. Although uncommon in blacks, melanoma tends to be of the acrolentiginous type. Look for black dots on the palms and soles or under the fingernail. Treat with surgery; if surgery fails, the prognosis is poor.

Kaposi's sarcoma: seen in AIDS patients. Look for classic mucosal lesions or an expanding, strange rash or skin lesion that does not respond to multiple treatments. (See figure below.)

Paget'« disease of the nipple: watch for a unilateral red, oozing, and crusting nipple in an adult woman. An underlying breast: cancer with extension to the skin must be ruled out.

Stomatitis: watch for deficiencies of B-complex vitamins (riboflavin, niacin, pyridoxine) or vitamin C,

Classic cerebrospinal fluid findings in different conditions

0 0

Post a comment