Ans. b (Atopic dermatitis) (Ref. H - 18th/pg. 52, 52)Half of patients with Atopic dermatitis (AD) present within the first year of life, and 80% present by 5 years of age. About 80% ultimately coexpress allergic rhinitis or asthma. The infantile pattern is characterized by weeping inflammatory patches and crusted plaques on the face, neck, and extensor surfaces. The childhood and adolescent pattern is marked by dermatitis of flexural skin, particularly in the antecubital and popliteal fossae. AD may resolve spontaneously, but approximately 40% of all individuals affected as children will have dermatitis in adult life. The distribution of lesions may be similar to those seen in childhood; however, adults frequently have localized disease, manifesting as lichen simplex chronicus or hand eczema (see below). In patients with localized disease, AD may be suspected because of a typical personal history, family history, or the presence of cutaneous stigmata of AD such as perioral pallor, an extra fold of skin beneath the lower eyelid (Dennie-Morgan folds), increased palmar skin markings, and an increased incidence of cutaneous infections, particularly with Staphylococcus aureus. Regardless of other manifestations, pruritus is a prominent characteristic of AD in all age groups and is exacerbated by dry skin. Many of the cutaneous findings in affected patients, such as lichenification, are secondary to rubbing and scratching.SKIN FEATURES OF ATOPIC DERMATITIS# Atopic Pleat (Dennie-Morgan fold): An extra fold of skin that develops under the eye.# Cheilitis: Inflammation of the skin on and around the lips.# Hyperlinear Palms: Increased number of skin creases on the palms.# Hyperpigmented Eyelids: Eyelids that have become darker in color from inflammation or hay fever.# Ichthyosis: Dry, rectangular scales on the skin.# Keratosis Pilaris: Small, rough bumps, generally on the face, upper arms, and thighs.# Lichenification: Thick, leathery skin resulting from constant scratching and rubbing.# Papules: Small raised bumps that may open when scratched and become crusty and infected.# Urticaria: Hives (red, raised bumps) that may occur after exposure to an allergen, at the beginning of flares, or after exercise or a hot bath.# White dermographism: excessive redness along line of stroke with thin objecteTYPES OF ECZEMA (DERMATITIS)# Allergic contact eczema (dermatitis): A red, itchy, weepy reaction where the skin has come into contact with a substance that the immune system recognizes as foreign, such as poison ivy or certain preservatives in creams and lotions.# Atopic dermatitis: A chronic skin disease characterized by itchy, inflamed skin.# Contact eczema: A localized reaction that includes redness, itching, and burning where the skin has come into contact with an allergen (an allergy-causing substance) or with an irritant such as an acid, a cleaning agent, or other chemical.# Dyshidrotic eczema: Irritation of the skin on the palms of hands and soles of the feet characterized by clear, deep blisters that itch and bum.# Neurodermatitis: Scaly patches of the skin on the head, lower legs, wrists, or forearms caused by a localized itch (such as an insect bite) that become intensely irritated when scratched.# Nummular eczema: Coin-shaped patches of irritated skin--most common on the arms, back, buttocks, and lower legs--that may be crusted, scaling, and extremely itchy.# Seborrheic eczema: Yellowish, oily, scaly patches of skin on the scalp, face, and occasionally other parts of the body.# Stasis dermatitis: A skin irritation on the lower legs, generally related to circulatory problems.