Hand and Foot Dermatitis

A hallmark histologic feature of dermatitis is edema between epidermal keratinocytes (spongiosis). When enough edema accumulates, cell-cell adhesions (desmosomes) rupture, forming microvesicles. The microvesicles become visible macroscopically only after they enlarge. In areas other than the hands and feet, these vesicles typically rupture quickly and are not noticed. However, on the hands and feet, because of their thicker stratum corneum, vesicles tend to persist longer and become visible. Visibility of these vesicles indicates dyshidrotic dermatitis (a misnomer because it has nothing to do with sweating or abnormal sweat glands).

The most severe form of dyshidrotic dermatitis, pompholyx, is characterized by coalescence of vesicles, forming larger bullae. Pompholyx is called cheiropompholyx when on the hands, podopompholyx when on the feet, and cheiropodopompholyx when on both hands and feet.

Erythema, scaling, and skin thickening may progress to pruritic vesicles or bullae on the palms, sides of the fingers, or soles (called dyshidrotic dermatitis), which can rupture, resulting in erosions and crusting. The vesicles may be the first symptom noticed. Depending on the etiology and exposures, symptoms can be intermittent.

Frequent or prolonged water contact (eg, frequent handwashing, work involving water or wet substances), particularly with detergents, is a common trigger, particularly in patients with atopy.

Diagnosis of hand and foot dermatitis can usually be inferred from location and appearance of the skin lesions.

Differential diagnosis of hand and foot dermatitis includes

Fungal infections Overview of Dermatophytoses Dermatophytoses are fungal infections of keratin in the skin and nails (nail infection is called tinea unguium or onychomycosis). Symptoms and signs vary by site of infection. Diagnosis is by... read more , which have a similar skin inflammatory reaction, also cause pruritus, erythema, and scaling. Vesicles and blisters may become apparent (bullous tinea), typically visible only on the hands and feet, as with hand and foot dermatitis. The most discriminating differentiating feature, when present, is the characteristic annular shape of the fungal infection due to the centrifugal growth of dermatophytes in the skin.

Palmoplantar psoriasis Psoriasis Psoriasis is an inflammatory disease that manifests most commonly as well-circumscribed, erythematous papules and plaques covered with silvery scales. Multiple factors contribute, including... read more may also be difficult to differentiate from hand and foot dermatitis. Features of palmoplantar psoriasis that can help in differentiation include erythematous and scaly plaques that are very sharply demarcated, sterile pustules, and other signs of psoriasis, such as psoriatic nail changes and psoriatic plaques elsewhere. Also, vesicles are possible with hand and foot dermatitis but are not a feature of palmoplantar psoriasis. However, vesicles and pustules can both be visible, for example:

Many disorders other than dermatitis can affect the hands and feet. Among these are

Keratolysis exfoliativa (also known as lamellar dyshidrosis or dyshidrosis lamellosa sicca) is not an inflammation of the skin (and thus not a dermatitis). It affects the hands and feet and is characterized by annular erythema over the volar aspects of the hands and feet with air-filled blisters, possibly followed by peeling. Small annular collarettes of white scale may affect the palms (less often the soles) but spare the dorsal hands and feet. No fluid-filled blisters are present. Keratolysis exfoliativa may be aggravated by warm weather, hyperhidrosis, friction, and water contact.

Hand-foot syndrome is known by a variety of terms, including acral erythema, palmar-plantar erythrodysesthesia, toxic erythema of the palms and soles, Burgdorf reaction, and toxic erythema of chemotherapy. It represents cutaneous toxicity caused by certain systemic chemotherapies (eg, capecitabine, cytarabine, fluorouracil, idarubicin, doxorubicin, taxanes, methotrexate, cisplatin, tegafur). Symptoms begin with tingling in the palms and/or soles, followed by edema and tender, symmetrical erythema, particularly over the fat pads of the distal phalanges. Pain, numbness, flaking, or blistering of the palms and soles can develop.

Treatment should be directed at the cause when possible.

Patients should avoid contact allergens Allergic contact dermatitis (ACD) Contact dermatitis is inflammation of the skin caused by direct contact with irritants (irritant contact dermatitis) or allergens (allergic contact dermatitis). Symptoms include pruritus and... read more as well as skin irritants Irritant contact dermatitis (ICD) Contact dermatitis is inflammation of the skin caused by direct contact with irritants (irritant contact dermatitis) or allergens (allergic contact dermatitis). Symptoms include pruritus and... read more , particularly frequent or prolonged contact with water and detergents.

Topical corticosteroids can be used, with the potency based on dermatitis severity. Antihistamines can help control pruritus.

Phototherapy with narrowband ultraviolet B (UVB) or with soak PUVA (in which patients soak their hands and/or feet in a psoralen solution before exposure to UVA) can help.

Superinfection is treated with topical or systemic antibiotics. For severe disease, systemic corticosteroids can be used, preferably only short term. Occasionally, if long-term systemic immunosuppressive treatment is required, cyclosporine, mycophenolate, or methotrexate can be given.