Acropustulosis is an uncommon skin condition that causes itchy bumps, or pustules, to develop on the skin. It usually appears in babies but can also affect adults.
Acropustulosis typically occurs on the palms of the hands and soles of the feet.
Although the pustules can be itchy and uncomfortable, the condition is not serious and tends to resolve by the time the child reaches 3 years of age. Infantile acropustulosis does not cause any lasting complications.
In this article, we describe the symptoms and causes of acropustulosis, and we list the available treatments.
Acropustulosis causes recurrent, itchy pustules on the skin. Initially, the pustules appear as red, flat bumps, but they then fill with fluid that resembles pus. As this occurs, they become raised and turn yellow or white.
Pustules occur in groups, which are called crops. Crops come and go over the first few years of the infant's life. Periods during which the pustules are present are known as flares, and these typically last for 7 to 14 days. They tend to recur every 2 to 4 weeks.
Acropustulosis most commonly affects the palms and soles, but the crops can also appear on the:
- backs of the hands
Infants with this condition can seem irritable and uncomfortable due to the itchiness.
Although the condition does not cause lasting complications, the American Osteopathic College of Dermatology advise that the skin where the rash occurs may remain darker for some time after the rash clears. Eventually, the skin should return to its normal color.
Acropustulosis is most common in babies, but it can also affect older children and adults.
The exact cause of acropustulosis of infancy is unknown. Some cases develop after a scabies infection. Scabies is a highly contagious skin condition that occurs when the Sarcoptes scabiei parasitic mite burrows into the skin.
Acropustulosis may signify an allergic reaction to the scabies mite.
However, other cases of infantile acropustulosis occur independently of scabies infection. Unlike scabies, acropustulosis is not contagious.
Doctors are not sure why some babies get acropustulosis while others do not. The primary risk factor for acropustulosis in infants is age, with the lesions most commonly occurring in children under 3 years old.
Other risk factors include:
- scabies infection
- previous acropustulosis flare-ups
Doctors typically diagnose infantile acropustulosis by visually inspecting the lesions and ruling out the presence of scabies mites or burrows.
Occasionally, a doctor may order laboratory tests to exclude other conditions or check for an infection, such as chickenpox.
Sometimes, people mistake acropustulosis of infancy for other, similar conditions. These include:
- Scabies, a highly contagious parasitic skin infection.
- Dyshidrotic eczema, a skin condition that causes characteristic tiny, itchy blisters on the fingers, palms, and soles.
- Hand, foot, and mouth disease (HFMD), a viral infection often affecting children that causes mouth sores and a rash on the hands, feet, and buttocks.
- Impetigo, a common contagious skin infection that causes red sores with crusting on certain parts of the body, most commonly the face, hands, and feet.
- Transient neonatal pustular melanosis (TNPM), an uncommon condition that affects newborns and can produce pustules on any part of the body.
Not all cases of infantile acropustulosis require treatment. The condition usually resolves by the time a child is 3 years old.
To reduce the risk of skin damage or scarring, caregivers can put socks and soft cotton gloves on infants to prevent them from scratching the pustules.
When treatment is necessary, the options include:
Moderate to high potency topical steroids are typically the first treatment that doctors will recommend.
A topical steroid is an anti-inflammatory medication that requires application directly to the skin once or twice a day for several days to weeks. These medications are available as a cream, ointment, or solution.
Sometimes, topical steroids can cause skin dryness. Using an emollient afterward can prevent this. It is important to follow the doctor's instructions on how to use these medications, as prolonged or incorrect use can lead to side effects if the body absorbs too much of the steroid from the skin.
Antihistamines reduce the effects of histamine, a chemical that the body releases in response to allergens. As histamine also causes itching, antihistamine medications can provide relief from the itchiness of the pustules. People should only give these medications to infants on a pediatrician's recommendation, as they can have side effects that include drowsiness.
Doctors sometimes treat severe cases of infantile acropustulosis with dapsone (Aczone), an antibiotic that treats various skin conditions.
Doctors will carefully monitor babies receiving dapsone treatment.
Side effects can include:
More serious side effects, such as muscular weakness, can occasionally occur.
If the acropustulosis occurs alongside scabies, a doctor will prescribe medication to kill the scabies mites. Acropustulosis may still reoccur even after the successful treatment of scabies.
Not all scabies medications are suitable for infants, but those that are include:
- Permethrin (Elimite) — this topical cream is suitable for those aged 2 months and older.
- Ivermectin (Stromectol) — this oral medication is suitable for children weighing 15 kilograms (kg) or more, although the Food and Drug Administration (FDA) have not yet approved it for this use.
Acropustulosis causes very itchy, raised bumps on the skin. It usually occurs in babies but can also affect older children and adults.
Acropustulosis usually develops on the hands and feet, but it may also appear on other areas of the body.
Although uncomfortable, the condition is not serious and will usually completely resolve by 3 years of age. Many children do not require any treatment for infantile acropustulosis, although some may need topical or oral medications.
Over time, flares will become less frequent and less severe, which means that they become easier to manage.