Diaper Rash: A-to-Z Guide from Diagnosis to Treatment to Prevention

Two Babies in diapers. Do they have diaper rash?

Introduction to diaper rash:

Diapers are a wonderful invention, controlling babies’ waste products in a relatively convenient, clean, and healthy way. Still, ever since children began to wear diapers, diaper rash has been the most common skin disorder of infancy.

What is diaper rash?

A surprising number of different entities fall under the label of diaper rash. A rash in the diaper area might be caused by friction, irritants, allergies, infections, seborrhea, psoriasis, diarrhea, or a long list of systemic diseases.

Skin wetness is the common denominator underlying the various causes of diaper rash. Even skin lesions of systemic illnesses tend to concentrate in areas where the skin is already damaged. Urinary wetness increases skin friction, raises the skin pH, makes the skin less cohesive, and makes it more permeable. These effects combine to intensify the action of stool enzymes or other irritants that then inflame the skin. In all of the diaper rashes mentioned above, the outermost layer of skin — stratum corneum — has been damaged. With this protective layer breached, it is easy for microorganisms such as yeast or bacteria to invade the inflamed skin. This makes the rash worse and less responsive to the usual treatments.

Who gets diaper rash?

Almost all children in diapers will get some diaper rashes, no matter how careful the parents are. Breastfed babies get fewer diaper rashes than formula-fed babies.

Diaper rashes are most common between 8 and 10 months old. They also frequently appear when babies are taking antibiotics, having loose stools, or have just started solid foods.

Anytime a baby sits too long in a wet diaper or a stool-soaked diaper, a rash can result.

What are the symptoms of diaper rash?

  • Friction rash. This is the most common form of diaper rash, and affects almost all babies at some time. It is most common in areas where friction is most pronounced, such as the inner thighs or under the elastic of diapers that are too tight. It comes and goes quickly, and responds well to frequent diaper changes, airing out, and protective barriers.
  • Irritant rash. This is most conspicuous on the exposed areas, such as the round part of the buttocks. It tends to spare skin folds and creases. It’s generally the result of contact with stool enzymes or irritants such as harsh soaps, baby wipes, detergents, or topical medicines.
  • Allergic rash. This may occur in combination with an irritant rash or by itself. It is also more common in exposed areas. The rash looks like poison oak.
  • Intertrigo. Moist heat causes this common type of diaper rash that occurs deep in the skin folds. The involved skin looks thin, as if it has lost several layers.
  • Seborrhea rash. A salmon-colored, greasy rash with yellowish scales characterizes this diaper rash that is also worse in the skin folds.
  • Psoriasis. This stubborn rash doesn’t necessarily look distinctive. Other signs of psoriasis usually accompany the diaper rash, such as pitting of the nails or dark red areas with sharp borders and fine silvery scales on the trunk, face, or scalp.
  • A number of rare diseases such as congenital syphilis, histiocytosis X, zinc deficiency, Wiscott-Aldrich syndrome, acrodermatitis enteropathica, and Jacquet’s dermatitis all cause characteristic diaper rashes. These are extremely uncommon, but should be considered in prolonged, severe rashes that are unresponsive to the appropriate therapy.
  • Yeast is by far the most common type of organism found in a diaper rash. The organism is quite prevalent and thrives in warm, moist skin. Yeast involvement should be suspected in any diaper rash that has not improved dramatically with 72 hours of appropriate therapy. Current or recent antibiotic use makes a yeast infection even more likely, since this reduces the amount of the skin’s ‘good’ bacteria that fight infection. Classically, a yeast rash is beefy red with sharp raised borders and white scales. Small satellite lesions surround the main rash. Even without the classic pattern, yeast is often present.

Is diaper rash contagious?

Most types of diaper rash are not contagious.

How long does diaper rash last?

If a diaper rash does not improve within 72 hours of appropriate attention, contact your pediatrician for further evaluation.

How is diaper rash diagnosed?

The initial diagnosis of a diaper rash is made by inspecting the skin of the diaper area. If the rash does not improve as expected with treatment, further evaluation is sometimes necessary.

How is diaper rash treated?

Common diaper rashes are treated with frequent diaper changes, airing out, and protective lotions or creams while the baby is in the diaper.

Yeast diaper rashes require the addition of an anti-yeast cream.

The treatment of other specific diaper rashes varies depending on the specific type.

How can diaper rash be prevented?

Change dirty diapers as soon as possible, gently cleaning the diaper area to reduce exposure to urine and stool.

Airing out the diaper area can help prevent rashes.

Breastfeeding, avoiding unnecessary antibiotics, and taking yogurt or beneficial bacteria when antibiotics are needed can prevent diaper rashes.

Related concepts:

Dermatitis – Diaper; Yeast infection – Diaper area.

Dr. Greene is a practicing physician, author, national and international TEDx speaker, and global health advocate. He is a graduate of Princeton University and University of California San Francisco.

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