Actinic Keratosis: Two Cases

September 2, 2002

A 63-year-old woman seeks evaluation of a persistent, rough, red area onthe dorsum of her left index finger. The lesion has been present for severalmonths. The patient’s manicurist is convinced it is a wart.

Case 1:
A 63-year-old woman seeks evaluation of a persistent, rough, red area onthe dorsum of her left index finger. The lesion has been present for severalmonths. The patient's manicurist is convinced it is a wart.

What does it look like to you?

A.

A wart.

B.

A granuloma annulare.

C.

An actinic keratosis.

D.

A seborrheic keratosis.

E.

A dermatophyte infection.

Your initial approach is to:

F.

Perform a potassium hydroxide evaluation.

G.

Perform cryosurgery.

H.

Offer reassurance only.

I.

Prescribe a corticosteroid cream.

J.

Prescribe a combination antifungal/corticosteroid cream.

Case 1:
The clinical appearance of this erythematous, hyperkeratotic lesion ona sun-exposed surface led to the diagnosis of an actinic keratosis,C. Thelesion was excised with cryosurgery, G.

Granuloma annulare is not typically keratotic; seborrheic keratosis is usuallywell-defined and not erythematous. Dermatophyte infections are scaly, not keratotic.A wart is more defined, rougher, and less keratotic than this patient's lesion.

Case 2:
A 70-year-old woman presents with anasymptomatic lesion on the top ofher scalp, which was first noticed byher hairdresser.

Which course of action do youpursue?

A. Perform a shave biopsy.
B. Perform a punch biopsy.
C. Perform an excisional biopsy.
D. Perform cryosurgery.
E. Prescribe 5-fluorouracil cream.
F. Provide reassurance, and reevaluatein 3 months for any changes.

Case 2: The lesion's clinical appearance and location in a sun-exposed areastrongly suggested the diagnosis of actinic keratosis. Although these precancerouskeratotic lesions are usually pink, as seen on the finger of the patient in Case1, they may be pigmented and can appear along the part line on the scalp ofwomen. Pigmented actinic keratoses may mimic seborrheic keratoses, nevi, ormelanomas. The keratotic surface is a clinical clue; if the lesion's identity is indoubt, a biopsy can confirm the diagnosis.

Cryosurgery, D, and topical 5-fluorouracil, E, are effective treatments.This patient responded well to cryosurgery; the lesion healed without scarring.

Case 3:For 2 months, a 68-year-old woman has been bothered by a pruritic rash on herlegs. She has mild hypertension; her blood pressure medication was changedshortly before the rash erupted.

Which of the conditions in the differential is the likely diagnosis?

A. Adverse drug reaction.
B. Stasis dermatitis.
C. Contact dermatitis.
D. Asteatotic eczema.
E. Lichen simplex chronicus.

Case 3: Some antihypertensive agents can cause fluid retention. In this patient, the recently prescribed calcium channelblocker produced significant fluid retention, which caused pitting edema and stasis dermatitis,B. The addition ofa diuretic to the drug regimen or a change in the class of antihypertensive can resolve this condition. The patient'srash cleared after her medication was changed.

A drug reaction features more extensive lesions. The patient had no history of contact dermatitis. Typically, lichensimplex chronicus erupts on the lateral aspect of the legs. The areas of dry skin of asteatotic eczema are more widespreadand not confined to the legs alone.

Case 4:
A 67-year-old man's thickened great toenails are unsightly and cause discomfortwhen he wears shoes. He seeks medical advice for the problem.

Can you identify this condition?

A.

Onychomadesis.

B.

Onycholysis.

C.

Onychoschizia.

D.

Trachyonychia.

E.

Onychogryphosis.

Case 4:Onychogryphosis,E-hypertrophyof the nails that results incurved growth-can be caused bytrauma, hallus vagus, chronic venousinsufficiency, and epidermal dysplasia.Generally, the nail of the great toe isaffected. Occasionally, poor nail hygienemay lead to a dermatophyte infectionin onychogryphotic nails; apotassium hydroxide evaluation ruledout a fungal infection in this patient.

Filing the nail and applications ofurea paste can be helpful. In recalcitrantcases, nail removal or matrixectomymay be required.

Onychomadesis is nail shedding;in onycholysis, the nail plate separatesfrom the nail bed. Onychoschizia featureslamellar splitting of the distalnail plate. Rough, brittle nails characterizetrachyonychia.