- Malignant melanoma:
- signs of malignancy include irregular borders, increasing in size, odd colors.
- They are generally more than 5 mm in diameter.
- Excisional biopsy is the FSOM to confirm the diagnosis and stage the lesion.
- Eventually, if it is melanoma, you’ll want to do a complete excision, which is curative a lot of the time.
- Melanoma:
- Majority of melanomas are associated with excess sun exposure.
- It happens more often in fair-skinned people, and usually develops in areas of the body that are intermittently exposed to
intense sunlight. - Should wear protective clothing when exposed to the sun.
- Sunscreen can reduce the incidence of basal and squamous cell cancer, but no evidence it helps to prevent melanoma.
- When hairs have split ends,
- it means that there is a toxic/chemical reaction causing the hair loss.
- Numerous drugs can cause hair loss (ex Li, thallium, chemo) but they do not affect the hair shaft or produce split ends.
- Psoriasis:
- an inflammatory skin disorder characterized by hyperproliferation and abnormal differentiation of the epidermis.
- There are sharply demarcated erythematous plaques involving the scalp, knees, extensor surface of elbows, neck, and back.
- Plaques are raised, with a thick silvery scale covering the surface.
- Psoriasis can also involve nails and joints, leading to psoriatic arthritis.
- Nail involvement presents as pitting over the nail plates.
- Arthritis can present with early morning stiffness which is relieved by physical activity.
- Some drugs can worsen psoriasis (b-blocker, Li, ACEI, NSAIDs, and antimalarials).
- Dx is a clinical one.
- Histology shows epidermal hyperplasia or hyperproliferation with neutrophilic infiltration in the stratum corneum and thinned to the absent layer of the epidermis.
- Worsening of psoriasis by certain drugs:
- As a general rule, all drug-induced skin rashes should be
managed by d/c the drug.
- As a general rule, all drug-induced skin rashes should be
- Rx of psoriasis:
- depends on the severity of the disease.
- Mild localized skin disease is Rx with topical steroids (betamethasone) or emollients or coal tar products (anthralin or calcipotriene).
- For extensive/widespread disease, Rx includes methotrexate, cyclosporine, UV radiation, or immunomodulators.
- Methotrexate is the initial DOC for pt with psoriasis and arthritis.
- Tinea Versicolor:
- fungal infection of the skin caused by Malassezia furfur.
- Presents with multiple small circular maculae which varies in color (white, pink, brown).
- Rash is more prominent in the summertime.
- Generally, the lesions are the only symptom.
- Rx with terbinafine antifungals.
- Alternatively, any of the azoles can also be used.
- Onychomycosis:
- fungal infection of toenails or fingernails.
- MCC is Trichophyton rubrum.
- Nail dystrophies from other diseases can mimic this (psoriasis, lichen planus).
- You can confirm dx with KOH exam of the nail scrapings.
- The KOH exam will show dermatophytes hyphae and arthrospores.
- Terbinafine is the TOC.
- An alternative is an itraconazole.
- Rosacea:
- chronic acneiform condition characterized by vascular dilation in the central face.
- Presents in adults 30-60.
- There are exacerbations and remissions.
- Symptoms include facial erythema, telangiectasias, and papules/pustules.
- Looks a lot like acne, but no comedones are present.
- Rx with topical metronidazole.
- Pt with rosacea often have ocular symptoms.
- Chalazion is a common one (it’s a cyst in the eyelid). Other eye complications include foreign body sensation and conjunctivitis.
- Alopecia Areata:
- Discrete, smooth, and circular areas of hair loss over the scalp with no scaling.
- Usually develops over a few weeks and has a recurring pattern.
- There is usually regrowth of hair in the involved areas over time. There is no associated scaling, scarring, or inflammation.
- Rx is with topical or intralesional steroids.
- Even after Rx, there is still a chance of recurrence, although it does speed up hair growth.
- Tinea capitis:
- Can present with a patch of hair loss on the scalp.
- The lesion is well-demarcated, scaling, and somewhat erythematous.
- Dx is usually with KOH exam of the hair stubs.
- Microsporum Canis is a cause, which will have a bright green fluorescence when a lesion is observed under Wood’s UV lamp.
- Keloid:
- benign fibrous growth that develops in scar tissue.
- These lesions can be painful and disfiguring.
- Rx with intralesional steroids.
- Look for hx of trauma (ex earring piercings)
- Actinic Keratosis:
- Presents as a slowly growing reddish-brown skin lesion.
- It’s pre-malignant, with the potential to become squamous cell cancer of the skin.
- Tetracycline:
- often used for Rx of acne.
- Doxycycline is a phototoxic agent and makes ppl more susceptible to sunburn.
- On a side note, doxy can also cause esophageal ulceration if you don’t drink it with enough liquid.
- Rx for sunburn includes replacement of lost fluids and relief for pain/pruritis with NSAIDs.
- Diphenhydramine can be used for the itching.
- Isotretinoin (systemic retinoid):
- can cause hypertriglyceridemia in up to 25% of pt.
- Thus, there is a risk of acute pancreatitis.
- Look for the kid who is getting isotretinoin for acne Rx who develops pancreatitis.
- If a pt develops triglyceridemia > 800, should d/c the drug.
- Topical Retinoid:
- teratogenic.
- Topical retinoids aren’t associated with systemic side effects (hyperTG or hepatotoxic).
- Herpes Zoster:
- d/t reactivation of latent VZV infection earlier In life.
- Any kind of stress on the body (fracture, infection, surgery) can reactivate the latent infection.
- Presents with grouped vesicles in a specific dermatome, usually unilateral.
- Pain is another prominent feature.
- Rx with acyclovir.
- Localized zoster lesions are transmitted only via direct contact with open lesions.
- Contact precautions aren’t necessary for the community setting.
- In the hospital, however, should put the pt in contact isolation until all the lesions have crusted.
- As age increases, there is a higher chance that a recurrence will happen.
- Postherpetic neuralgia (PHN):
- Defined as persistence of pain or other symptoms for > 1 month after the resolution of skin lesions of herpes zoster.
- It’s described as a burning sensation in the involved dermatome.
- Agents proven to be effective for the pain include TCA, topical capsaicin cream, gabapentin, and long-acting oxycodone.
- Photoaging:
- arises from aging and UV light damage.
- Intrinsic aging tends to cause fine wrinkles on an otherwise smooth skin surface.
- If there is photodamage, it can result in coarse, deep wrinkles on a rough skin surface.
- Photoaged skin is often marked with actinic keratoses, telangiectasias, and brown spots.
- Cigarette smoke can have a significant impact on the skin (more wrinkles, especially at lateral corners of eyes).
- Rx with tretinoin.
- It helps reduce fine wrinkles, mottled hyperpigmentation, and roughness of the face.
- It can also reduce actinic keratoses.
- Erythrasma:
- infection of the skin that occurs most often in intertriginous spaces and is d/t C. minutissimum.
- Use of wood lamp shows coral-red fluorescence caused by Corynebacterium porphyries.
- Pityriasis rosea:
- self-limited condition manifests first as a single primary plaque (herald patch).
- A generalized eruption develops 1-2 weeks later, with fine, scaling papules and plaques in a Christmas tree distribution.
- Poison Ivy dermatitis:
- presents with pruritic dermatitis composed of papules and vesicles which are distributed in a linear fashion.
- Multiple lesions can be present in various areas around the body since touching other parts of the body will transfer the poison ivy resin.
- More serious reactions can evolve into vesicles which can exude a serous fluid.
- Tinea pedis:
- MC dermatophyte infection.
- Usually accompanied by involvement in another area (hands, neck, nails, or groin).
- Presents as a slowly progressive, pruritic, erythematous lesion, usually btw the toes and extending to the sole and side of the foot.
- There is a sharp border btw the involved and uninvolved skin.
- Self limiting, but recurrent.
- Rx with an antifungal cream.
- Seborrheic Dermatitis (dandruff):
- Pink-red erythema and scaliness in the scalp, face, and sometimes upper trunk.
- Pruritis is usually mild.
- Rx with selenium shampoo.
- Sometimes it’s the first presenting sign of HIV infection.
- Lichen Planus:
- generally presents in middle age.
- Involves skin, nails, mucous membranes of the mouth, and external genitalia.
- Lesions are shiny, discrete, intensely pruritic, polygonal-shaped violaceous plaques and papules that are present on the flexural surfaces of the extremities.
- Wrists are commonly involved.
- A characteristic whitish lacy pattern is often seen on the surfaces of the papules and plaques.
- Mucous membranes of the mouth and external genitalia can also be involved.
- Dx is clinical.
- Histology can show hyperkeratotic epidermis with irregular acanthosis and focal thickening in the granular layer of the epidermis.
- Lichen planus is seen in association with liver disease, especially advanced disease 2/2 hep C infection.
- Consider screening for it with H and P if you see lichen planus.
- Acne Rx:
- Mild acne is Rx initially with a topical retinoid.
- Moderate acne can be Rx with topical retinoid and benzoyl peroxide or topical antibiotic.
- More severe acne is treated by adding a topical antibiotic or systemic abx.
- Abx are used only in combination with the other stuff.
- Very severe cases can be rx with oral isotretinoin is no response after 3-6 months with combo of abx, topical retinoid, and benzoyl
peroxide.
- Pressure Ulcer:
- Stage 1 has nonblanchable erythema of intact skin.
- Stage 2 has a partial thickness loss of the epidermis, dermis, or both.
- Stage 3 is deeper, causing a full-thickness loss with damage that might involve underlying fascia.
- Stage 4 is very deep, and can possibly extend into the bone, muscle.
- Should cover the wound with dressing/saline moistened gauze.
- Pt should be turned every 2 hours to prevent it.
- Sporotrichosis:
- fungal infection d/t sporothrix schenckii.
- Usually seen in ppl who do outdoor activities.
- Starts as a popular lesion over the site of inoculation.
- Eventually, the lesion ulcerates and there is non-purulent drainage over the lesion.
- Dx is clinical and with culture.
- Itraconazole for 3-6 months is Rx.
- Tattoo:
- Laser removal of tattoos can be done, but they lead to scar marks and skin discoloration.
- Porphyria cutanea tarda:
- d/t deficiency of uroporphyrinogen decarboxylase.
- Painless blisters and increased fragility of the skin are seen.
- There can also be facial hypertrichosis and hyperpigmentation.
- Dx is with elevated urinary uroporphyrins.
- Phlebotomy or hydroxychloroquine can provide relief.
- There is often an association with hep C, and if pt also has Hep C, can give interferon-alpha.
A Future Doctor
