Derm Flashcards
Molluscum Contagiosum is caused by? Treatment?
This young patient is presenting with firm, dome-shaped papules that started as small spots and have rapidly grown. The appearance of these lesions is classic for molluscum contagiosum (MC), a skin growth caused by poxvirus infection. The disease is spread by physical contact. Self-inoculation can occur, so once lesions are localized, they should be covered and touched as little as possible. The lesions of MC are 2 to 5 mm in diameter, with a shiny surface and central indentation or umbilication, and can sometimes be polypoid or even have a stalk-like base. In children, MC can be observed and will usually self-resolve over 12 months, but in patients with a high risk of transmission or in whom the lesions are distressing, cryotherapy can be beneficial.
There are a variety of treatments for molluscum contagiosum. In general, adolescents and adults with sexually transmitted molluscum contagiosum should be treated to avoid the spread of the disease to others. Early treatment is also indicated in the setting of immunocompromised individuals in whom infections can become severe. As noted above, treatment in children should be individualized to the situation.
Erythema Multiforme is associated with?
The patient is suffering from erythema multiforme (EM), a cutaneous hypersensitivity inflammatory disease. This is evidenced by the vesicular rash on his lip and the prodrome of fever and malaise common to acute viral illnesses.
The most common triggers for EM are herpes simplex virus (HSV) infection, followed by Mycoplasma pneumoniae infection. It occurs most often in young men. A prodrome of fever, malaise, and itching or burning at the site of the eruption can occur. Early lesions are red maculopapular spots and progress to the characteristic “targetoid” lesions. Targetoid lesions have a center blister surrounded by pale edema and a ring of erythema. Target lesions are the hallmark of EM, although they may not always be present. Lesions are usually symmetric and most commonly appear in a symmetrical distribution on the extensor surfaces of the acral extremities and subsequently spread in a centripetal manner. The lesions may be asymptomatic, but they also may present with itching and burning.
Eruptions can also occur in the oral cavity and can often be associated with the vesicular lesions of HSV. EM can progress to toxic epidermal necrosis or Stevens-Johnson syndrome. If linked to an HSV infection, acyclovir can be prescribed to decrease recurrent rashes.
Because of the association between HSV and EM, all patients with EM should be closely evaluated for concomitant HSV infection and appropriate treatment.
What is bullous pemphigoid?
This elderly patient is presenting with a 1-month history of an intensely pruritic rash followed by the development of tense bullae over her chest and arm without mucous membrane involvement and a negative Nikolsky sign. This is the classic presentation of bullous pemphigoid.
Bullous pemphigoid is a bullous disorder of autoimmune origin, characterized by autoantibodies to the epidermal basement membrane. Most patients are over 60 years of age and present with widespread blistering. Often there is a prodrome for weeks to months that consists of an intensely pruritic papular rash that may coalesce and form plaques. These blisters are often described as tense. Plaques and papules, if present, may turn darker in color as vesicles and bullae rapidly appear on their surface. Firm pressure on the blister will not result in extension into normal skin (negative Nikolsky sign). Immunofluorescence reveals autoantibodies against hemidesmosomal proteins with IgG and C3 at the basement membrane zone in most cases. Management is often with oral prednisone. Prognosis is variable, with many cases spontaneously resolving.
What is Pemphigus Vulgaris?
Flaccid vesicles and erosions of the skin and mucous membranes, desquamative gingivitis; scalp involvement common
Almost always has oral involvement
Flaccid blisters
Positive Nikolsky sign
No pruritis
What determines the border cuts for melanoma excision?
Malignant melanoma is an aggressive type of skin cancer, causing the highest number of deaths of all skin cancers. Prognosis is directly related to tumor thickness. Cure rates by stage are: Stage I (T1 or T2a, N0, M0) >80%; Stage II (T2b-4, N0, M0) 60-80%; Stage III (N1-3), M0) 10-60%; Stage IV (M1) < 10%. Many factors may influence survival, including the presence of tumor-infiltrating lymphocytes, mitotic rate, location, ulceration, gender, age, and regression. Tumor thickness, ulceration, and lymph node involvement have the greatest predictive value regarding prognosis and therapy.
Although the presence of a vertical growth phase may be an independent risk factor for metastases of these tumors, the single greatest risk factor for metastasis is the depth of invasion. Current guidelines for adequate resection margins of melanoma of the skin are based on several prospective, randomized clinical trials. The overall guidelines for resection margins based on these investigations are:
0.5 cm for melanoma in situ
1 cm margins for tumors less than 1mm thick
1-2 cm margins for tumors between 1mm and 2mm thick
2 cm for tumors greater than 2mm thick
what is characteristic of Rosacea? Treatment?
Given this patient’s history of rash, facial flushing, and episodic nature, she is most likely suffering from rosacea. Rosacea can often be confused with acne (even called acne rosacea if there are pustules), but there are differences, as noted below.
Rosacea is a chronic inflammatory condition characterized by facial erythema and sometimes closed comedones; this is termed acne rosacea or papulopustular rosacea. Rosacea affects all ages and consists of 4 different types: erythematotelangectatic; papulopustular or acne rosacea; phymatous rosacea, which includes the presence of rhinophyma or enlargement of the nose; and ocular rosacea. Factors that commonly trigger rosacea include sunlight, emotional stress, weather changes, exercise, alcohol consumption, and spicy foods. Studies of rosacea and Demodex mites reveal that people with rosacea have an increased number of Demodex mites on the skin, with the rosacea possibly being a response of the skin to the feces of the mites. Management of rosacea involves behavioral modifications such as avoidance of triggers and strict use of daily sunscreen, in addition to topical metronidazole cream or oral antibiotics, most commonly doxycycline or tetracycline. Azaleic acid is also commonly used topically to treat the papules, pustules, and erythema associated with rosacea.
In Melanoma when to do a sentinel lymph node biopsy?
Melanoma is an increasingly common malignancy that can be cured with early detection and excision. Breslow depth is the measured vertical thickness of the melanoma and is the single most important prognostic factor. Clark level involves an anatomic level of invasion. Management of melanoma is dependent on the depth of invasion and the stage of the melanoma. Melanomas of >0.8 mm thickness or <0.8 mm with ulceration are the accepted indications for sentinel lymph node biopsy. Management of a positive sentinel lymph node has become controversial. Historically, a positive sentinel lymph node resulted in a complete lymphadenectomy. However, recent data suggest observation with serial ultrasonography may be adequate. Melanoma in situ (not penetrating the epidermis) requires excision with 5-mm margins. Depending on the stage of the disease, the excision margins, and sentinel lymph node biopsy, use of adjuvant treatment, such as oncologic drugs, may be warranted. There are currently new drugs, such as BRAF inhibitors, that are being used in the treatment of metastatic disease with good results.
Describe Pemphigus Vulgaris? Pathophysiology? Treatment?
Pemphigus vulgaris (PV) is an autoimmune bullous disorder of the skin, characterized by the presence of autoantibodies directed against adhesion molecules (specifically desmoglein 3 as well as 1) in the epidermis. The mean age of onset is 60 years old, and there is no gender predilection. PV usually manifests with painful, fragile blisters in the oropharynx, chest, face, or perineal regions. Bullae often originate in the mouth, making it difficult for patients to eat as once these rupture they tend to leave open erosions. In some patients, there may not be any intact bullae and erosions may be the only finding visible on examination. Traction pressure on intact skin causes bullae formation or skin sloughing (Nikolsky sign). Erosions last for weeks before healing. This often results in areas of skin hyperpigmentation that heal completely without scarring. Biopsy of the skin shows separation of the epidermal cells with the retention of an intact basement membrane. Anti-epidermal antibodies (IgG and C3) are demonstrated by immunofluorescence. Management is typically with oral prednisone with or without adjuvant agents such as azathioprine or cyclophosphamide.
Psoriasis treatment?
This patient is presenting with pruritic, plaques over his elbow and arm that are consistent with psoriasis. Topical agents are generally the most appropriate treatment for mild cases of psoriasis(usually defined as < 5% body surface area involved) such as in this patient. Topical therapy is usually a combination of a high potency corticosteroid such as betamethasone combined with either vitamin D analogs (calcipotriene or calcitriol) or the vitamin A derivative tazarotene. Options for more severe and diffuse psoriasis include phototherapy, anthralin, methotrexate, cyclosporine, and biologic agents such as TNF-alpha inhibitors. Even in severe cases, topical therapy is generally used for limited, resistant, lesions.
Psoriasis is a common, chronic, inflammatory disorder of the skin and joints that affects nearly 7 million persons nationwide. Not all cases of psoriasis itch, and it is commonly estimated that some 10%-40% of patients have no pruritis with psoriasis. The etiology is multifactorial, with both genetic and environmental factors leading to the development of the disease. Factors that may exacerbate psoriasis include human immunodeficiency virus (HIV) infection, physical trauma, infections, drugs, and the winter season due to low humidity.
Psoriasis characteristically appears as red scaly patches on extensor surfaces of the skin as seen in the image. The scaly patches caused by psoriasis, called psoriatic plaques, result from areas of inflammation and excessive skin production that rapidly accumulate at these sites and take a silvery-white appearance. Although plaques frequently occur on the extensor surfaces, they can affect any area of the body, including the scalp and genitals. Psoriasis may affect the scalp and nails, and may also cause psoriatic arthritis, a type of inflammatory arthritis, which affects 5%-8% of psoriatic patients.
How to biopsy a melanoma?
This patient presents with a family history of skin cancer with a changing mole, in which case malignant melanoma should always be suspected. Malignant melanoma is the least common type of skin cancer, but causes the most deaths from skin cancers. Risk factors for the development of melanoma include personal or family history of melanoma, history of multiple blistering sunburns, history of atypical nevi, and fair skin. Remember the ABCDEs of melanoma: Asymmetry, Borders, Color, Diameter greater than 6 mm, and Evolution (evolution or changing of the lesion is the most important of these factors). Poor prognosis is associated with depth of invasion of the lesion. Excisional biopsy is ALWAYS the method of choice for removal of suspected melanotic lesions, as this allows for full-thickness biopsy and helps to determine depth of invasion, which is vital in the staging of this disease. Management of malignant melanoma is dependent on the stage of disease, and may involve excision with margins, sentinel lymph node biopsy, and chemotherapy. Early detection of these lesions greatly improves prognosis of the disease.
ABCDE’s of melanoma? what is the strongest predictor of melanoma even more than family hx?
Remember the ABCDEs of melanoma: A, asymmetry; B, borders (irregular borders); C, color (change in color: dark brown, red, blue, and white are most concerning); D, diameter (>6 mm diameter), and E, evolution (MOST IMPORTANT of the ABCDEs as a predictor of melanoma).
What is a common nail bed finding with psoriasis?
The most common nail findings associated with psoriasis include onycholysis, oil spots, and nail pitting with others generally being considered to be less common (see below). Psoriasis of the distal nail bed often causes onycholysis.
