Dyshidrotic Eczema: Blisters on the Fingers and Their Causes

Small blisters on the fingers and palms are frightening: it seems that they are contagious and dangerous. This may be dyshidrotic eczema — a condition whose symptoms can be kept under control, but which tends to come back.

What dyshidrotic eczema is

Dyshidrotic eczema, also known as pompholyx and dyshidrosis, is one of the types of eczema that affects the hands or feet. Its course is usually long: flare-ups alternate with quiet periods. The names "vodyanitsa," "hydrotic eczema," and "hydro eczema" refer to the same condition — that is what it is called in everyday speech and in older texts.

The term itself is historical. It was once believed that the blisters arise from blockage of the sweat gland ducts, and this explanation is outdated, although the word has remained. Eczema in general is not contagious: its cause is unknown, most likely a combination of genetic and environmental factors. People with eczema more often have hay fever and asthma. The disease was described in 1873, and clarity on its etiology has not increased since then.

What the blisters and watery rash on the fingers look like

The first symptom is itching, burning, or tingling at the site of the future rash. Then fluid-filled blisters appear: small, very itchy, sometimes oozing. The favored locations are the fingers and palms, the sides of the hands; the toes and feet are also possible. Small subcutaneous blisters on the fingers look like clear droplets inside the skin.

The rash appears in episodes, each lasting about 2–3 weeks. When the blisters subside, the skin becomes dry, cracks, and hurts, sometimes bleeds. On dark skin, the blisters may look darker than on light skin.

Possible causes and triggering factors

The exact cause is unknown. Dyshidrosis is regarded as a polyetiological disorder: an allergic reaction associated with food or drug toxidermia, sensitivity to nickel, hereditary predisposition, and adverse environmental factors are discussed. Some episodes develop after stress. These are hypotheses, not proven mechanisms.

List of triggers that are considered likely:

• contact with strong chemicals — soap, cleansers, detergents;
• allergy or sensitivity to metals, such as nickel or cobalt;
• regular wetting of the hands — for example, in hairdressers;
• stress;
• heat and sweating.

The link to a specific trigger often remains a supposition.

How it differs from other rashes on the hands

Psoriasis and fungal infections, including ringworm and foot fungus, produce a similar picture. Peeling skin on the hands and feet can also be a symptom of scarlet fever. Therefore, you cannot make a diagnosis on your own: if in doubt, you need a doctor.

How a doctor establishes the diagnosis

The basis is examination and clinical evaluation with differential diagnosis. Additionally, the doctor may assess the degree of allergic sensitization of the body and the state of the gastrointestinal tract.

When to see a dermatologist

The reason for a visit is suspected pompholyx or any skin changes that bother you. A separate warning sign: the blisters are very painful, ooze yellow or green pus, or are covered with a yellow-brown crust — this is what a superimposed infection looks like. If the symptoms are severe or the treatment prescribed by the doctor does not produce results, the patient is referred to a dermatologist.

This condition by itself is not a reason to call an ambulance. 103/112 — for life-threatening conditions (for example, sudden severe shortness of breath or loss of consciousness); purulent crusts and painful blisters are a reason to make an appointment with a doctor, not to call an ambulance.

This material is for reference: it explains what is happening to the skin, but does not replace a doctor's consultation — a diagnosis is made at an appointment, not from a photograph.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer