Rashes in the diaper area are one of the most common problems encountered in infants. Most occur between 9-12 months.

Diaper Dermatitis

1. This is the most common cause of diaper rash and is due to irritation by the combination of urine, feces, friction, and moisture. 
2. The rash is usually over the areas in contact with the wet diaper- buttocks, lower abdomen, medial thighs, labia, mons pubis, and scrotum. Because of the lack of contact, the fold areas are usually spared. 
3. The rash is erythematous, papular, and has areas of scaling. The skin appears edematous and inflamed causing the infant to be irritable. With chronicity, the skin will get dry. Chronic irritation can lead to ulcerations. 
4. Because of increased moisture, there is a change in the permeability of the epidermis allowing increased entrance of irritants. This is enhanced by stool enzyme activation.
Secondary bacterial and yeast infections are common.
5. Prevention and Treatment
a. Keep area dry by frequent diaper changing and using disposable diapers that have increased absorption.
b. decrease scrubbing of the area when changing 
c. use only water or mild soaps
d. Barrier ointments including A&D, Desitin, and petroleum jelly should be applied after each diaper change to decrease skin contact with moisture. It is not necessary to remove barrier agent after each change because scrubbing it off can further irritate the area.
e. Cornstarch and other powders will keep area dry and decrease friction. Avoid inhalation of powder that can lead to aspiration. 
f. Anti-inflammatory topical steroid are useful if above measures fail. Use only low potency steroids for short periods. The diaper area has very thin skin, and the use of potent topical steroids may lead to thinning, striae, and adrenal suppression. Avoid combination preparations of antifungal and steroids because the steroid is usually high potency and should not be used in the diaper area.

1. Beefy red rash with peripheral scaling and satellite papular lesions. Usually involves the folds and often well demarcated. Often is a secondary infection.
2. Check for oral thrush because occur together
3. May be associated with prior antibiotic use. 
4. Treat with ketoconazole, clotrimazole, econazole, or nystatin. Must treat contact dermatitis and inflammatory changes as well. Steroid and antifungal can be applied together if necessary.
5. Keep area dry and change frequently.
6 If recurs, check for sources of fungus on mother's breast, vaginal area, and pacifiers.

1. Superficial Staphylococcal infection most common with pustules and crusted lesions
2. Treat with topical Mupiricin or Neosporin. Extensive infection requires oral anti-staphylococcal coverage.

1. Red, scaly waxy patches. Often associated with cradle cap, axillary, neck folds and behind the ear lesions. Usually present at 2-3 weeks of life and disappears by 3-4 months. Not pruritic. Often secondarily infected with Candidiasis.
2. Ketoconazole or hydrocortisone cream may help in severe cases.
3. Very severe, Leiner's disease phenotype, has been described with SCIDs, hypogammaglobulinemia, and hyperimmunoglobulinemia.

1. Rare cause of severe diaper rash that is unresponsive to treatment
2. Macules, papules, vesicles. petechiae, and ulcers
3. Systemic manifestations - anemia, lymphadenopathy, hepatosplenomegaly

1. Secondary to zinc deficiency
2. Scaly crusty plaques in diaper area as well as periorally. May have alopecia and paronychia.
3. May be associated with malabsorption syndromes.
4. Responds to zinc replacement

1. Copper colored maculopapular scaly rash
2. Systemic symptoms- bony changes, hepatosplenomegaly, anemia.

1. Uncommon cause of rash in diaper area because the presence of the diaper prevents scratching. Vigorous scratching during diaper changes will occur.

1. Arnsmeier, Sheryl and Paller, Amy. Getting to the Bottom of Diaper Dermatitis. Contemporary Pediatrics. November 1997