Dermatology ImagesHARVARD PCIM 2019

Psoriasis Vulgaris - slide 1The typical lesion of psoriasis is a sharply demarcated erythematous papule or plaque with an adherent silvery scale. The regions of psoriasis generally occur on the elbows, knees, scalp, and gluteal cleft. Nail involvement is present in over 50% of patients (including "pitting" or onycholysis of the nail). Psoriasis can also be in a generalized distribution throughout the body, or can be located in intertriginous areas. Plaques located in intertriginous areas tend to lack scale secondary to being located in a moist environment. The differential diagnosis for psoriasis includes tinea corporis, candidiasis, intertrigo, seborrheic dermatitis, pityriasis rubra pilaris, secondary syphilic and pityriasis rosea.

Psoriasis Vulgaris - slide 2The typical lesion of psoriasis is a sharply demarcated erythematous papule or plaque with an adherent silvery scale. The regions of psoriasis generally occur on the elbows, knees, scalp, and gluteal cleft. Nail involvement is present in over 50% of patients (including "pitting" or onycholysis of the nail). Psoriasis can also be in a generalized distribution throughout the body, or can be located in intertriginous areas. Plaques located in intertriginous areas tend to lack scale secondary to being located in a moist environment. The differential diagnosis for psoriasis includes tinea corporis, candidiasis, intertrigo, seborrheic dermatitis, pityriasis rubra pilaris, secondary syphilic and pityriasis rosea.

Pityriasis Rosea - slide 1Pityriasis rosea is an acute self-limiting inflammatory dermatosis of unknown etiology. A "herald patch" may be a single lesion which precedes the onset of multiple oval scaling papules and plaques which are located on the trunk and neck and may include the proximal extremities. The scale, described as a collarette scale, is a delicate scale near the border of the papule or plaque. The lesions are typically a tan or salmon colored papule or plaque and the distribution may be similar to that of a "Christmas tree pattern" which is that the lesion starts at the neck or upper trunk and spreads downward to the proximal extremities.

Pityriasis Rosea - slide 2The differential diagnosis includes tinea corporis, guttate psoriasis, lichen planus, drug eruption or secondary syphilis. It is very important to examine the palms, soles and oral mucosa which may be affected in secondary syphilis but should be clear of lesions in patients with pityriasis rosea.

Bullous PemphigoidBullous pemphigoid is an autoimmune disorder which generally occurs in patients between ages 60 to 80. The lesions as noted above can vary between a pink urticarial plaque which can progress to a large tense bulla. The bullae may arise in normal or erythematous skin. The lesions can be in a generalized or localized distribution and often occur in the axilla, groin, and flexural areas. Approximately 1/3 of patients also have involvement of the oral mucosa. Differential diagnosis includes pemphigus, erythema multiforme, bullous drug eruption or dermatitis herpetiformis.

Herpes Simplex - slide 1Herpes simplex is a virus infection which is characterized by grouped vesicles on an erythematous base. The vesicles may contain a clear or yellow fluid. A herpes simplex infection may be a primary infection, or recurrent. A primary herpes outbreak may be accompanied by fever, headache, myalgia and malaise. A recurrent herpetic infection is often preceded by a prodrome which may include a burning, numbness, itching or tingling sensation before the eruption appears.

Herpes Simplex - slide 2The differential diagnosis for a primary intraoral herpes simplex virus infection includes aphthous stomatitis, erythema multiforme, or hand-foot-and-mouth disease. The differential diagnosis in a recurrent lesion includes a contact dermatitis or a fixed drug eruption.

Herpes zosterHerpes zoster is associated with reactivation of the varicella virus. Herpes zoster is characterized by unilateral, dermatomal, root and confluent pink erythematous papules, vesicles, and pustules. The lesions may become crusted or shallow erosions with time. Herpes zoster occurs predominantly on the thoracic dermatomes. In immunocompromised patients, herpes zoster may be multidermatomal, generalized or recurrent. The differential diagnosis of herpes zoster includes a contact dermatitis, bullous impetigo, erysipelas, or a zosteriform herpes simplex virus infection.

Peutz JeghersPeutz Jeghers syndrome is an autosomal dominant disorder that can include numerous lentigines occurring around the mouth, eyes, and on the lips, oral mucosa, hands, and feet. The above slide demonstrates the brown labial macules located on the upper and lower lips. Peutz Jeghers syndrome can be associated with gastrointestinal polyps or malignant neoplasms. Differential diagnosis for mucosal pigmentation includes normal variant of racial pigmentation, drug induced pigmentation, or amalgam tattoo.

Acanthosis NigricansA diffuse, velvety thickening and hyperpigmentation of the skin which occurs predominantly in the axillae, elbows, knees, over knuckles of the hands and other body folds. This slide demonstrates the hyperpigmentation with a thickening of the skin with a velvety appearance and accentuation of the skin lines. The differential diagnosis of hyper-pigmented and thickened flexural skin includes tinea versicolor, x-linked ichthyosis, or nicotinic acid ingestion. A variant, malignant acanthosis nigricans, may be related to adeno-carcinoma of the GI or GU tract or lymphoma. This can involve the body folds, mucus membranes and mucocutaneous junctions. Benign acanthosis nigricans can be related to endocrine disorders and insulin resistance should be evaluated.

Seborrheic KeratosisThis is a benign epidermal growth which can vary in size from 2 mm to approximately 2 cm. This lesion is a brown and dark brown, "stuck-on" appearing sharply marginated growth. The surface of these lesions can be warty, crumbly, or greasy. These lesions commonly occur on the trunk, head, neck, and extremities and spare the palms and soles. The DDX includes a nevus, pigmented basal cell carcinoma, malignant melanoma, wart, or actinic keratoses. If a patient notes a rapid increase in the size and number of seborrheic keratoses accompanied by pruritus, then the "sign of Leser-Trelat" needs to be considered. This can be a cutaneous sign of an internal malignancy such as adeno-carcinoma of the stomach, ovary, breast, or uterus.

Alopecia AreataAlopecia areata is a localized loss of hair in a round or oval patch with no inflammation. In the slide you see two sharply outlined portion of the scalp without any evidence of scale, erythema, atrophy, or scarring. Alopecia areata most often affects the scalp and can also affect the eyebrows, eyelashes, beard, or hair located elsewhere on the body. The differential diagnosis of nonscarring alopecia includes secondary syphilis, trichotillomania, and fungal infection. Alopecia areata can be associated with autoimmune diseases, such as Hashimoto's thyroiditis, atopic dermatitis, vitiligo and pernicious anemia.

ScabiesScabies is an infestation of the skin caused by Sarcoptes scabiei. The lesions in the slide are multiple crusted papules and plaques which are located on the abdomen. The distribution is generalized and common sites include the web spaces, wrist, areola, peri- umbilical area, genital area, and feet. In a male a "scabeticnodule" on the glans penis is highly suggestive of a diagnosis of scabies. A common diagnostic finding in scabies is a burrow which is a serpiginous line located most commonly in the web spaces. Scabies is intensely pruritic. The differential diagnosis includes irritant or contact dermatitis, other bites or infestations, or drug eruption. The diagnosis can be made with a scraping which can reveal a scabies mite or feces or eggs as depicted in the slide.

Scabies Preparation

Scabies Mite

Pyoderma gangrenosumPyoderma gangrenosum is a rapidly developing, painful ulcer with undermined borders and a necrotic base. The primary lesion as shown above can be a deep seated nodule which can quickly progress to an ulcer with purulent drainage. Pyoderma gangrenosum is frequently associated with rheumatoid arthritis, myeloproliferative diseases, Crohn's disease and ulcerative colitis. The differential diagnosis includes stasis ulcer, arterial ulcers, polyparteritis nodosa,

rheumatoid vasculitis, atypical mycobacterial infection, and Wegener's granulomatosis.

Necrobiosis lipoidicaNecrobiosis lipoidica is a cutaneous disorder which usually occurs on the lower legs in diabetic patients. Early lesions include a well demarcated orange-red, indurated plaque with an atrophic epidermis and visible telangiectatic blood vessels. The older lesions as seen above, often have ulceration within the plaque and when these ulcers heal there is often a depressed scar. The differential diagnosis of a cutaneous yellow/ brown plaque includes sarcoidosis, diabetic dermopathy and a xanthoma.

Pseudomonas infection of the nailPseudomonas infection of the nail is caused by Pseudomonas aeruginosa. Clinical findings include as seen above a green-black discoloration of the nail. The differential diagnosis includes a fungal infection, hemorrhage, or an acral-lentiginous melanoma

Erythema nodosumErythema nodosum is an inflammatory reaction in the subcutaneous fat. It often represents a hypersensitivity response to an infection or inflammation. Clinical findings include erythematous, painful, tender nodules on the lower legs. This can be accompanied by ankle edema. Erythema nodosum has multiple etiologies, and it is important to rule out an underlying infection, sarcoidosis, or drugs such as sulfonamides or oral contraceptives which may precipitate the development of erythema nodosum.

Dysplastic nevusA nevus is a neoplasm of pigment forming cells. Dysplastic nevi are either congenital or acquired. Clinical features of a dysplastic nevus include a nevus which is irregular in color, is asymmetrical in shape, has an irregular border, is greater than 6 mm and is changing in size. The differential diagnosis includes a malignant melanoma or a seborrheic keratosis.

Lentigo malignaA lentigo maligna is a flat, intraepidermal neoplasm and a precursor of a lentigo maligna melanoma. Lentigo malignas can vary in size from 3.0 to 20.0 cm in size. The lesion can have irregular borders, and variable colors including tan, white, brown, dark brown, and black. Lentigo maligna is a precursor lesion for a lentigo maligna melanoma. The differential diagnosis includes a pigmented actinic keratosis, a pigmented basal cell carcinoma, a lentigo and a melanoma.

Melanoma-in-situ with regressionMalignant melanoma is a cancerous neoplasm of the melanocytes or nevus cells. Clinical features of a melanoma include asymmetry in shape, border irregularity, mottled color including variable colors such as brown, black, gray, red, white, and blue; and diameter is usually larger than 6.0 mm. Regression in a melanoma lesion is characterized by areas of hypopigmentation such as illustrated in the slide above. The differential diagnosis for a pigmented lesion which exhibits asymmetry, border irregularity, color change, or diameter greater than 6 mm is a malignant melanoma.

Melanoma, recurrentThe clinical description of a recurrent melanoma is a pigmented lesion which arises in a pre-existing scar at the site of a previous melanoma. The lesion pictured above is a dark brown/ black pigmented papule with an irregular "smudged border" and the lesion is arising out of a scar.

Blue nevusBlue nevi are small, blue or gray nodules which usually occur early in life. Clinically a blue nevus can appear similar to a nodular melanoma, and the differential diagnosis includes a malignant melanoma or a "lead" tattoo.

Kaposi's sarcomaKaposi's sarcoma is a malignant tumor derived from the endothelial cells. It is manifested by multiple vascular tumors that usually occur on a cutaneous surface where they can appear as a purple macule, plaque, or nodule. The clinical findings of a Kaposi's sarcoma include purple macules, papules, plaques, and nodules. In the "classic type" of Kaposi's sarcoma, multiple lesions are located on the lower legs in loder Mediterranean or Jewish males and may be accompanied by edema. In AIDS associated Kaposi's sarcoma lesions can occur anywhere on the body. Lymphadenopathy is also present in many AIDS patients with Kaposi's sarcoma. The differential diagnosis includes ecchymosis, hemangioma, and bacillary angiomatosis.

UrticariaUrticaria is a condition characterized by wheals resulting from acute dermal edema. Clinical findings of urticaria include edematous plaques with pale centers and red borders. They can also have geographic shapes and may also be confluent. The lesions are usually generalized, but may be scattered. Pruritus is usually present with urticaria. The differential diagnosis includes erythema multiforme, a drug eruption, urticarial vasculitis, the urticarial phase of bullous pemphigoid and erythema marginatum.

Sarcoid, cutaneousSarcoidosis is a chronic granulomatous inflammation which can affect multiple organs but commonly presents with cutaneous plaques, bilateral hilar adenopathy, and pulmonary infiltration. Clinical characteristics of the cutaneous sarcoid lesion include an annular pink or tan plaque ranging in size from 0.5 to 1.0 cm. The lesions can be located on the extremities, buttocks, trunk, face, in old scars, or a scarring alopecia may be present in the scalp. The differential diagnosis of the lesion noted above includes tinea facialis, leprosy, leishmaniasis, discoid lupus and a superficial basal cell carcinoma.

Dermatomyositis - slide 1Dermatomyositis is a systemic disease in which the cutaneous manifestations include a heliotrope rash on the face, erythema of the face, neck or upper trunk, and flat topped papules over the knuckles (Gottron's papules) as pictured above. The nails have a characteristic finding of periungual telangiectasia as pictured above.

Dermatomyositis - slide 2The differential diagnosis of these cutaneous findings includes lupus erythematosus, mixed connective tissue disease, steroidmyopathy and toxoplasmosis.

Secondary syphilis - slide 1Syphilis is a sexually transmitted infection caused by treponema pallidum. A painless ulcer or chancre at the site of inoculation is a cutaneous finding in primary syphilis, and it is most commonly firm with an indurated border. Secondary syphilis appears 2-6 months after the primary infection and 2-10 weeks after the appearance of the primary chancre. The cutaneous manifestations of secondary syphilis include scattered macules and papules and papulosquamous lesions located in a generalized eruption on the trunk.

Secondary syphilis - slide 2The lesions generally occur on the palms and the soles and can be described as discrete copper colored keratotic papules. The differential diagnosis for a disseminated papulosquamous eruption involving the trunk and body includes pityriasis rosea, viral exanthem, tinea corporis, acute guttate psoriasis, and a drug eruption.

Malar rash of lupus erythematosusSystemic lupus erythematosus is a connective tissue disease which includes fever, cutaneous lesions, arthritis, renal, cardiac and pulmonary disease. Cutaneous findings in systemic lupus erythematosus as noted above include a malar rash which is a bright red, sharply demarcated plaque on the face which spares the nasolabial folds. The malar rash in lupus can often have a violaceous hue and is often accompanied by telangiectasia. The differential diagnosis of a malar rash includes seborrheic dermatitis, and rosacea.

Porphyria cutanea tardaPorphyria cutanea tarda is a disorder of abnormal porphyrin metabolism and excessive accumulation of various porphyrins. PCT is characterized by subepidermal blisters on the dorsum of the hands, and excessive uroporphyrin excretion in the urine. Cutaneous manifestations can also include facial hair on the temples and cheeks and a mottled facial pigmentation. The lesions on the hand noted above include multiple tense bullae, erosions, crust, milia and scars on the dorsum of the hand.

Henoch-Schonlein purpura: HSP is a hypersensitivity vasculitis associated with IgA desposition in blood vessels; group A streptococci may be the antecedent infection. Hypersensitivity vasculitis causes "palpable purpura," and the lesions pictured are round papules with hemorrhagic blister and necrosis. The differential diagnosis of palpable pupura includes leukocytoclastic vasculitis, drug eruption, rheumatoid vasculitis, PAN, meningococcemia, and gonococcemia.