(See also Definition of Dermatitis Definition of Dermatitis The meaning of the word "dermatitis" is inflammation of the skin. However, in clinical dermatology, dermatitis is used to describe a variety of different skin conditions that share the same... read more .)
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 (called cheiropompholyx when on the hands, podopompholyx when on the feet, and cheiropodopompholyx when on both hands and feet).
Symptoms and Signs
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 can 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:
When dyshidrotic dermatitis and palmoplantar psoriasis coexist
When vesicles in dyshidrotic dermatitis become superinfected
When patients with palmoplantar psoriasis become sensitized (eg, to topical corticosteroids) and develop an allergic contact dermatitis
When palmoplantar psoriasis is triggered (koebnerized) by an allergic contact reaction
Many disorders other than dermatitis can affect the hands and feet. Among these are
Fungal infections (eg, tinea manuum, tinea pedis Tinea Pedis (Athlete's Foot) Tinea pedis is a dermatophyte infection of the feet. Diagnosis is by clinical appearance and sometimes by potassium hydroxide wet mount, particularly if the infection manifests as hyperkeratotic... read more , cutaneous yeast infections Candidiasis (Mucocutaneous) Candidiasis is skin and mucous membrane infection with Candida species, most commonly Candida albicans. Infections can occur anywhere and are most common in skinfolds, digital web spaces, genitals... read more )
Viral infections (eg, herpetic whitlow Herpetic Whitlow Herpetic whitlow is a cutaneous infection of the distal aspect of the finger caused by herpes simplex virus. (See also Overview and Evaluation of Hand Disorders.) Herpetic whitlow may cause... read more , warts Warts Warts are common, benign, epidermal lesions caused by human papillomavirus infection. They can appear anywhere on the body in a variety of morphologies. Diagnosis is by examination. Warts are... read more )
Bacterial infections (eg, impetigo Impetigo and Ecthyma Impetigo is a superficial skin infection with crusting or bullae caused by streptococci, staphylococci, or both. Ecthyma is an ulcerative form of impetigo. Diagnosis is clinical. Treatment is... read more , atypical mycobacterial infections Nontuberculous Mycobacterial Infections Mycobacteria other than the tubercle bacillus sometimes infect humans. These organisms (called nontuberculous mycobacteria) are commonly present in soil and water and are much less virulent... read more )
Parasitic infections (eg, scabies Scabies Scabies is an infestation of the skin with the mite Sarcoptes scabiei. Scabies causes intensely pruritic lesions with erythematous papules and burrows in web spaces, wrists, waistline, and genitals... read more , cutaneous larva migrans Cutaneous Larva Migrans Cutaneous larva migrans is the skin manifestation of hookworm infestation. Cutaneous larva migrans is caused by Ancylostoma species, most commonly dog or cat hookworm Ancylostoma braziliense... read more )
Keratolysis exfoliativa (lamellar dyshidrosis)
Keratolysis exfoliativa (also known as lamellar dyshidrosis or dyshidrosis lamellosa sicca) is not a dermatitis but rather a dermatosis. It affects the hand 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 of the cause when possible
Topical drugs and phototherapy
For severe disease, sometimes systemic corticosteroids or immunosuppressants
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.